CHNG 1: TNG QUAN

1.1 Cc khi nim c bn

1.1.1 Bo h lao ng (BHL)

1.1.1.1 Khi nim

Khi nim: l h thng nhng vn bn, nhng qui nh, qui ch v lut ca

Nh nc, nhng bin php kinh t - x hi, t chc, k thut, v sinh v nhng bin

php tr liu phng nga nhm m bo s an ton, duy tr sc khe v kh nng lm

vic ca con ngi trong qu trnh lao ng. Nh vy, BHL trc tin l h thng

nhng hot ng nh hng vo bo v sc khe v kh nng lao ng ca ngi lao

ng (NL). Nhng bin php c th ca BHL chnh l nhng thanh phn ca h

thng ny, chng bao gm:

Cc bin php k thut an ton sn xut

Cng tc v sinh lao ng

Cng tc xy dng, t chc thi hnh cc ch , lut l v lao ng (ch lao

ng, ngh ngi, lm thm gi, khm sc khe)

1.1.1.2 Mc ch ngha

a. Mc ch

Bo m s ton vn thn th ca ngi lao ng (NL), ngn nga tai nn lao

ng (TNL), bnh ngh nghip (BNN), v s thit hi v ti sn, mi trng xung

quanh.

Gim tiu hao sc khe, nng cao ngy cng gi cng, gi vng v duy tr sc khe

lu di cho NL, lm vic c nng sut v cht lng cao.

b. ngha

Chnh tr: Thc hin tt cng tc BHL l biu hin tnh cht u vit ca ch

XHCN, qu trng lao ng, coi con ngi l vn qu nht ng thi th hin r tnh

ng v tnh giai cp.

X hi: Lm tt cng tc BHL s ngn nga v loi tr TNL v BNN, NL c

pht trin ton din v th lc v tr lc, n nh hnh phc gia nh, gp phn pht

trin x hi.

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Kinh t: Lm tt cng tc BHL s gi gn c sc khe v kh nng lm

vic lu di ca NL, do NL c th lm vic lin tc, nng cao nng sut v cht

lng sn phm, gim c cc chi ph do TNL v BNN gy ra, ng thi m bo

ko di tui th ca trang thit b, nng cao hiu qu kinh

1.1.1.3 Ni dung v tnh cht ca cng tc bo h lao ng

a. Ni dung

Nghin cu, xy dng cc qui nh, bin php v k thut an ton (KTAT)

phng trnh TNL

Nghin cu, xy dng cc qui nh, bin php v v sinh lao ng (VSL)

phng trnh BNN

Nghin cu, xy dng cc ch bi dng/ ngh ngi mt cch hp l, khoa

hc m duy tr sc khe lu di cho NL, nng cao nng sut v cht lng sn

phm.

b. Tnh cht

Tnh khoa hc k thut: Th hin trong cc nghin cu, tnh ton v a ra cc qui

phm/ tiu chun an ton trong thit k, ch to, lp t v vn hnh;

Tnh php lut: Cc qui nh BHL l mt b phn ca php lut XHCN, mi cng

dn phi tun th v chp hnh, mi hnh vi vi phm u b x pht theo php lut;

Tnh qun chng: Tt c mi ngi (NSDL v NL) u l i tng bo v ng

thi cng l ch th hnh ng do vy u c lin quan trong cng tc BHL

1.1.1.2 Tai nn lao ng v bnh ngh nghip

Tai nn lao ng (TNL): l tai nn xy ra vi NL khi thc hin cng vic

hoc nhim v c c quan, x nghip phn cng. Nh vy, TNL c th xy ra trong

thi gian lm vic ti c quan, trong thi gian i cng tc hoc ngoi lnh th ca c

quan. Tai nn xy ra trn ng i t nh n ni lm vic v ngc li cng c

xem l tai nn lao ng.

Cc nguy him c th gy thng tch/t vong. Ri: khi trn cao. T ng: sn

thao tc trn trt, c l thng, c chng ngi vt hoc inh nh li . Vng bn, vt

ri: t trn cao hoc do n mn, ph . Va p, ng: thit b chuyn ng. Li, cun,

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ct: b phn truyn ng (dy cua roa, li ca, mi ..). Chy, n. ng vt: rn, ong,

Nhit : qu nng, lnh. in git. Ha cht c hi. Lam vic sat mep nc

Bnh ngh nghip (BNN): l bnh pht sinh mt cch t t do tc ng ca

nhng yu t c hi trong sn xut n cc c quan ca c th con ngi.

Cc nguy him gy bnh ngh nghip. Ting n. nh sang. Bc x, phng x. Rung/

chn ng. Ho cht c hi. Bi. Vi khun, siu vi, virt. K sinh trng: chy rn. T

th lm vic: ng, ngi, ci, nm, nhn qu lu. nhim mi trng.

1.1.1.4 Yu t sn xut nguy him (c hi)

Yu t sn xut nguy him (c hi): tai nn v bnh sinh ra do tc ng ca

nhng yu t xc nh ca mi trng xung quanh n con ngi. Nhng yu t m

tc ng ca chng n con ngi c th dn n tai nn gi l yu t nguy him, cn

dn n bnh hoc gim kh nng lao ng gi l yu t c hi. Nu yu t nguy

him (c hi) l kt qu ca hot ng sn xut hoc xut hin trong qu trnh sn

xut th gi l yu t sn xut nguy him.

Nh vy: Hat ng sn xut + Yu t sn xut nguy him (c hi) = tai nn

lao ng (bnh ngh nghip)

1.1.1.5 An ton lao ng v k thut an ton lao ng

An ton lao ng v k thut an ton lao ng: kh nng tc ng ln ngi

lm vic nhng yu t sn xut nguy him (c hi) xc nh tnh nguy him trong lao

ng. An ton lao ng (ATL) l trng thi iu kin lm vic m s tc ng

cc yu t sn xut nguy him (c hi) ln NL c lai tr.

H thng cc bin php t chc v cc phng tin k thut nhm ngn nga tc ng

cc yu t sn xut nguy him ln NL, ngha l ngn nga tai nn lao ng, ic gi

l k thut an ton lao ng.

V sinh lao ng: cc phng tin k thut nhm ngn nga bnh ngh nghip

l thnh phn quan trng trong cng tc v sinh lao ng. H thng cc bin php t

chc v cc phoing tin k thut ngn nga hoc lm gim s tc ng cc yu t sn

xut c hi ln NL c gi l v sinh lao ng (VSL)

1.1.1.6 Tnh trng khn cp v vng nguy him

3

Tnh trng khn cp: s kin, tnh trng khng mong i c th gy nguy hi

nghim trng n tnh mng con ngi, ti sn hoc mi trng xung quanh m cn

phi hnh ng gp, x l v gii quyt ngay c gi l tnh trng khn cp.

Vng nguy him: vng nguy him (c hi) l khong khng gian xc nh, ti

cc yu t nguy him (c hi) lun tn ti v tc ng mt cch thng xuyn, c

chu k hoc tc ng bt ng d gy tai nn (nhim c) con ngi, nu khng c bin

php phng nga.

iu kin lao ng: iu kin lao ng l t hp cc yu t t nhin, x hi,

kinh t, t chc, qun l, k thut, cng ngh, php l th hin qua cng c, phng

tin lao ng, i tng lao ng, qu trnh cng ngh, mi trng lao ng v s tc

ng tng h ca chng vi ngi lao ng ti ni lm vic, to nn bi cnh nht

nh m ngi lao ng phi tri qua qu trnh lao ng.

1.1.2 Nhng quy tc chung v an ton lao ng

Cc quy tc an ton khi sp xp vt liu. Cc quy tc an ton khi i li. Cc

quy tc an ton ni lm vic. Cc quy tc an ton khi lm vic tp th. Cc quy tc an

ton khi tip xc vi cht c hi. Cc qui tc an ton khi s dng dng c bo h

1.1.3 Cc quy tc an ton my mc

Cc quy tc an ton khi vn hnh my khoan. Cc qui tc an ton khi s dng

thang ,my vn chuyn. Cc qui tc an ton khi dng my ti. Cc qui tc an ton i

vi dng c th cng. An ton khi lm vic vi mt s my mc c th. An ton khi

lm vic vi my dp. An ton khi lm vic vi my mi. An ton khi lm vic vi

my cun p. An ton khi lm vic vi my ca g li trn. An ton khi lm vic vi

my bo g dng ng c. An ton khi lm vic vi cn cu. An ton khi lm vic vi

xe nng. An ton khi lm vic vi bng chuyn. An ton khi vn hnh vi my n to

hnh. An ton khi lm vic vi my nghin. An ton khi lm vic vi my tin. My ct

gt tng hp. An ton khi lm vic vi my kh long. An ton khi lm vic vi my

git quay. An ton khi lm vic vi my vt li tm. My h quang dng in xoay

chiu

1.1.4 Mt s bin php phng nga

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Tu theo tnh hnh c th c th p dng cc bin php phng nga sau y:

Bin php k thut cng ngh. Bin php k thut v sinh. Bin php t chc lao ng

khoa hc. Bin php phng h c nhn. Cc bin php v qun l hnh chnh.

1.1.4.1 Trang b bo v c nhn

Khi nim: Trang b bo v c nhn (trang b BHL) c hiu l tt c nhng

phng tin, dng c hoc t bo v c th hoc b phn no ca NL v phi

mang trn ngi khi lm vic.

Nhng trang b bo v c nhn khi nhng tc ng c hi ca mi trng

xung quanh. Nhng trang b thuc nhm ny gm: thit b th chng bi, mt n phng

c, khu trang; thit b bo v tai, mt, mt n bo v tai, m, nt bng tai; knh bo

v mt khi bi, khi, kh ha cht; qun o bo h lao ng chng nng, nng, bi;

tp d chng d bn, ha cht; ng bo h bo v chn khi bn, ly, nc, gng tay

cao su bo v tay khi s tip xc trc tip vi ha cht, nc.

Nhng trang b bo v c nhn khi tai nn c nhn khi tai nn lao ng. Nhng trang

b thuc nhm ny bao gm: nn bo h (m bo h) bng nha polyetylen bo v u,

qun o bo h lm gim va chm, try, xc; giy, ng bo h bo v chn khi dp

thng; phng tic bo v tay (gng tay bng vi b, cao su cch in), tht lng an

ton kh lm vic trn cao, o phao an ton khi lm vic trn mt nc.

Cc loi c bn: nn bo h, qun o bo h, giy bo h, gng tay bo h,

knh bo v mt, phng tin bo v c quan h hp, phng tin bo v tai, o phao.

1.2. An ton lao ng, phng chy cha chy, bo v mi trng.

1.2.1 An ton ha cht v in

1.2.1.1 An ton ha cht

Bng 1.2.1.1: Tiu chun nh nc

Tiu chun nh nc Nhm TCc cht c hi

Phn loi v nhng yu cy chung v an ton

TCVN

3164 79Noxious subbstances Classification and General

safety Requirements.

C hiu lc

t 1-1-1981Tiu chun ny p dng cho cc cht c hi c trong nguyn liu, sn phm,

bn thnh phm v ph liu ca qu trnh sn xut v quy nh nhng yu cu chung v

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an ton khi sn xut, s dng v bo qun, v gii hn v sinh v kim tra hm lng

cc cht c hi trong khng kh khu vc lm vic.

Tiu chun ny khng p dng i vi cc cht phng x v cc cht sinh hc

(cc phc cht sinh hc phc tp, vi khun, vi trng v.v...). Cc thut ng v nh

ngha s dng trong tiu chun ny c trnh by trong ph lc.

1.2.1.2 Phn lai

Tu theo mc tc ng ln c th cc cht c hi c chia ra lm bn

nhm nguy him. Nhm th nht Cc cht cc k nguy him. Nhm th hai Cc

cht rt nguy him. Nhm th ba Cc cht nguy him. Nhm th t Cc cht t

nguy him

Nhm nguy him ca cc cht c hi c xc nh ty thuc vo nh mc

v ch s nu ra trong bng sau

Bng 1.2.1.2: Phn loi nhm nguy him cc cht c hi

Tn ch snh mc cho cc nhm nguy himI II III IV

Nng o gii hn cho

php ca cc cht c hi

trong khng kh khu vc lm

vic, mg/m3

Nh hn

0,10,1 1,0

Ln hn

1,0 10,0

Ln hn

10,0

Liu gy cht trung bnh khi

a vo d dy, mg/m3Nh hn

1515 150

Ln hn

150

5000

Ln hn

500

Liu gy cht trung bnh khi

a ln da, mg/kgNh hn

100100 500

Ln hn

500

2500

Ln hn

2500

Nng gy cht trung bnh

trong khng kh khu vc lm

vic:mg/m3.

Nh hn

500

500

5000

Ln hn

5000

50000

Ln hn

50.000

H s kh nng gy nhim Ln hn 300 30 Nh hn Nh hn6

c ng h hp 300 30 30 3H s vng tc ng cp tnh Nh hn

6,06,0 18 18 54,0

Ln hn

54,0H s vng tc ng mn

tnh

Ln hn

10,010,0 5

Nh hn

5,0 2,5

Nh hn

2,51.2.1.3 Yu cu v an ton

cc x nghip m hot ng sn xut c lin quan n cc cht c hi

Cc bin php cn c bit ch m bo an ton lao ng khi tip xc vi

cc cht c hi

Nhng yu cu v gii hn v hm lng cc cht c hi trong khng kh khu

vc lm vic

Nhng yu cu ch yu i vi vic kim tra hm lng cc cht c hi trong

khng kh khu vc lm vic

1.2.1.4 An ton vi cht c v kh c

a. Kh H2S

Khi nim: Kh sunfuahydro (H2S) l cht c thn kinh mnh, rt c hi, khng mu

sc, nng hn khng kh, nng thp c mi trng thi. Kh sunfuahydro c th

lm t lit cc c quan h hp, hy dit h thn kinh nhng v tr nhy cm nht. Vi

nng trung bnh, kh H2S lm t lit khu gic ngay v con ngi khng th nhn

bit n bng mi. Vi nng cao, H2S c th gy cht ngi tc khc.

b. Mt s tnh cht ca H2S

Kh H2S c t trong 1,189; nng hn khng kh nn thng nm nhng ni thp v

khng thong kh nhng d phn tn theo chiu gi.

Kh sunfuahydro c tnh n mn cao i vi mt s kim loi v ha tan tt trong du,

nc. nhit 20C, kh nng ha tan ca kh H2S trong nc l 2,9 g H2S/ 100 ml

H2O. Khi thay i p sut v nhit , kh H2S c th tch ra khi cht lng.

Kh H2S chy c ngn la mu xanh lam, sinh ra kh sunfuadioxit SO2 cng l mt loi

kh rt c hi v c tnh n mn kim loi cao, c kh nng gy n khi ha trn vi

khng kh nng t 4,3 n 4,6%. Nhit chy ca H2S l 260C ( 500F ). H2S

c hn monoxit cacbon CO v tng t nh hydroxianit HCN.

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Cc kh c v hi c khc. Ngoi kh c hydrosunfua, trong cng tc du

kh ni ring v hot ng sn xut kinh doanh ni chung, ngi lao ng cn c th

phi tip xc v lm vic vi cc kh c, hi c khc. l cc hydrocacbon c

trong xng du v sn phm du m, hc n; cc kh c l sn phm ca qu trnh

oxit ha; cc hi c ca cc axit, amoniac; cc hi ca mt s kim loi

Cc kh v hi c t cc sn phm du kh. Cc kh v hi c t cc sn

phm du kh c th l toluen C6H5CH3, xylen C6H4(CH3)2, benzen C6H6, cc

hydrocacbon thm ny cng l nhng cht c chng gy t lit hng cu v ph hy

s hot ng ca hng cu no. Mt s hc n trong du m c th gy nn cc bnh

ung th nguy him. Nng ti a cho php ca mt s cht c hi c trnh by

trong bng 2 (phn phc lc).

Nng ti a cho php ti ni lm vic v khu dn c i vi benzen tng

ng l 5,0 v 0,8 mg/ m3. Nng ti a cho php 8 gi lm vic hng ngy i vi

khi, hi nha ng, hc n l 5 mg/ m3; cho 15 pht c mt l 10 mg/ m3. Cc kh

metan, etan v hi xng lm gim nhanh nng oxy trong khng kh, gy kh th,

nu nng ln s gy ra ng c v dn n t vong.

Mt s du m v sn phm ca chng tc ng ln da cn c th gy nn bnh ngoi

da ( chng vim da, bnh chm ).

Ngoi ra, cc kh metan CH4, etan C2H6 cn l nhng kh nguy him n khi ha

trn vi khng kh. Trong iu kin bnh thng, CH4 c th gy n khi ha trn vi

khng kh nng gii hn n 4,8 14%, vi C2H6 l 3,2 12,5%.

1.2.1.5 Cch phng chng kh, hi v khi c

Pht hin v cnh bo nng kh, khi, hi c. Phng chng r r thot cht

c. Gim thiu kh, khi thi trong cng nghip du kh. Khuych tn kh thi, lm

long nng . Thng gi v lm sch kh. Kh v lm sch cc kh thi, khi thi.

Kim sot nng kh, hi c. Bin php y t d phng. Thc hin cc bin php

mang tnh t chc php l. Cng tc v sinh. Thc hin ch vitamin ha v cc

thc ung b dng. S dng phng tin bo v c nhn

1.2.1.6 An ton in

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Khi qut chung: in l mt loi nng lng v cng quan trng i vi s

pht trin ca x hi v i sng con ngi. in l 1 loi vt cht v hnh khng nhn

thy c nhng li c tc dng rt ln i vi c th con ngi, do mc nguy

him cng khng th o lng ht c. Phn ln nhng tai nn xy ra l do va chm

phi nhng vt mang in gy in git, nhng cng c nhng trng hp khng va

chm m vn b tai nn, l do vt qu khong cch an ton i vi tng cp

in p gy nn phng in, sinh tia la in t chy con ngi.

Hu qu: Hu qu ca vic mt an ton in l dn n nhng tai nn lm t

vong, thng tch cho ngi v s c v my mc thit b, c bit l i vi nhng

ni c dy chuyn sn xut lin tc, d chy n dn n thit hi ti sn nghim

trng.Do m bo sn xut an ton, cn tm hiu k v k thut an ton in

c nhng bin php phng hu hiu v tun th nhng qui nh nghim ngt v An

ton in khi lm vic.

Cc tai nn v in: Tai nn in c th gp 3 dng: in git, t chy do h

quang in, chy n.

Cc yu t lien quan n tai nn v in: it tr ngi, dng in i qua

ngi, trng thi sinh l con ngi, mi trng xung quanh.

1.2.1.7 Cc bin php phng tai nn in

Bc cch in nhng ch hay va chm, nhng ch b h. Ro chn, treo bin

bo nhng ch nguy him (c in nguy him, c ngi lm vic cm ng in).

B tr nhng phn dn in h trn cao khng vi ti c nhm ngn nga s tip

xc tnh c ca con ngi. B tr cc thit b in trong cc khung, v, hp cch ly kn,

tm chn,con ngi khng th dng m khng s dng cc dng c chuyn dng

m. Ro chn chung quanh nhng thit b in c tnh nguy him cao ( trm bin p,

trm phn phi in,) nhm ngn nga ngi, sc vt n gn. Thc hin cch ly cc

phn, b phn dn in vi mi trng chung quanh.

Ni dy tip t, v thit b: ni t bo v l ni nhng phn, v thit b in

bng kim loi bnh thng khng c in vi t qua dy dn v cc bng thp chon

trong t. Cc thit b bng kim loi ( b cha du, bnh tch kh du,) cng phi

c ni t trng tnh in v nguy c chy n. Ngt bo v l s bo v tc ng

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nhanh hoc tc ng tc thi nhm m bo ngt t ng thit b in khi pht sinh

nguy him in git, xut hin dng r, xut mch. Tt c cc thit b in phi c bo

v chng ngn mch v chng cc ch phi tiu chun.

Gi khong cch an ton: 2 15kv: 0.7m. 15 35kv: 1.1m. 35 110kv: 1.4m.

220kv: 2.5m. 330kv: 3m. 330 500kv: 4m.

Hng nm kim tra lp cch in bng ng h M (>1K/1V)

T ng ct in khi c dng in r r ra v thit b.

Dng in p thp nhng ni cn thit: n xch tay, n chiu sng cng c

36v.Cc bin php bo v c nhnS dng cc dng c an ton v in.

So cch in (ng m cu dao cch ly c ly xa), km cch in, bt th in, gng

tay cch in, ng cch in, thm cch in .

Cc dng c an ton phi in: knh, gng tay vi bt, mt n, dy ai an

ton.Yu cu v s dng cc phng tin bo v c nhn.

Ch s dng cc dng c m bo cht lng do phi thng xuyn kim tra

m bo cc ch tiu k thut.

Khng c s dng qu cp in p cho php ca dng c. Cc dng c bo v

phi c bo qun ni cao ro, sch s, trnh ch c xng du, trnh b c xt b

mt.

1.2.1.6 Quy nh an ton in

Ch nhng ngi c chuyn mn v in v qua hun luyn an ton in

mi c bo dng, sa cha, ci to, lp t thit b in. Nhng ngi khng

chuyn v k thut in c th c php lm vic vi nhng dng c v c cu in

s dng in p thp ( 110V ).

Khi bo dng, sa cha thit b in t nht phi c 2 ngi tham gia, thc

hin cc bc c lp in, treo bin cnh bo cm ng in ti cu dao ngun trong

sut qu trnh lm vic, t cc thit b/ dng c in trn mt bng kh ro, s dng

qui trnh lm vic v tun theo giy php lm vic in, sau khi kt thc cng vic

phi nghim thu, tr giy php v thng bo ngi vn hnh a thit b vo hot

ng;

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Khi ng/ct thit b in cn c phiu thao tc/qui trnh lm vic v phi c

2 ngi tham gia trnh nhm ln.

Khng can thip vo my mc, thit b hoc kh c bt k no nu khng phi

l trch nhim ca mnh hoc khng c s phn cng v nu khng v mc ch bo

m an ton cho ngi v thit b. Khng t tin n nt hoc ng ngt cu dao,

ptomat ngoi chc trch ca mnh (nht l i vi cc my bm, my nn, qut

gi).

Phi ngt thit b ra khi ngun in v ni t thit b trc khi bo dng, sa

cha. Nu cn chiu sng cc b khi sa cha, phi dng n di ng cm tay 36V.

Khng t tin i vo vng nguy him ca thit b in hoc ng dy dn in v

khng t u ni thay i h thng in. Ti v tr c dng in cao th phi treo

bng cnh bo nguy him. Khng b tr thit b in trn mt bng m t c kh nng

dn in hoc d trt ng, sp .

Ngt khi ngun in cc thit b, dng c in khi khng s dng. Khi ngt mt

cu ch, cu dao, cng tc, mi ni in, ti v tr c lp phi treo bin thng bo hoc

kha cch ly.

t nht 2 ln/nm o kim tra in tr tip t ca thit b, nu s o >2 th phi

x l t gi tr

Cng tc PCCC l mt nhim v rt quan trng trong s nghip xy dng v

bo v t Quc, c bit l trong ngnh cng nghip kh nhm bo v con ngi, ti

sn, mi trng, gi gn an ninh trt t, an ton x hi. Lut Phng chy v cha chy

c Quc hi nc Cng Ho X Hi Ch Ngha Vit Nam kho X, k hp th 9

thng qua ngy 29-6-2001; Ch tch nc Trn c Lng k lnh ban hnh ngy

12/7/2001, qui nh:

PCCC l trch nhim ca mi c nhn, c quan, t chc, h gia nh trn lnh

th nc Cng Ho X Hi Ch Ngha Vit Nam (iu 5).

Cng dn 18 tui tr ln, sc kho c trch nhim tham gia vo i

PCCC c s ni lm vic hoc i dn phng ni c tr (iu 5).

Ngi lm vic trong mi trng nguy him v chy n hoc thng xuyn

tip xc vi cc cht nguy him v chy n phi c hun luyn v c chng ch hun

luyn nghip v v PCCC (iu 22). Cc hnh vi b nghim cm gm (iu 8): C

gy chy n lm tn hi n tnh mng, sc kho con ngi; gy thit hi ti sn ca

Nh nc, c quan t chc, c nhn; nh hng xu n mi trng, an ninh v trt t

an ton x hi.

Cn tr cc hot ng PCCC, chng ngi thi hnh nhim v PCCC.

Li dng cc hot ng PCCC xm hi n tnh mng, sc kho con ngi,

xm phm ti sn ca nh nc, c quan, t chc v c nhn.

Bo chy gi.

Sn xut tng tr, bo qun, s dng, mua bn tri php cht nguy him v

chy, n; vi phm nghim trng cc qui nh qun l s dng ngun la, ngun nhit

v cc Tiu chun v PCCC c Nh nc qui nh.

Thi cng nhng cng trnh c nguy him v chy n m cha c thit k c

duyt v PCCC; nghim thu v a vo s dng cng trnh c nguy him v chy, n

khi cha iu kin bo m an ton v PCCC.

Lm h hng, t thay i, di chuyn phng tin, thit b PCCC, bin bo,

bin ch dn v li thot nn.

12

1.2.2.2 K thut an ton khi vn chuyn cc cht d n

Khi nim chung v n

Hin tng n gm hai dng:

Hin tng n l hc: L hin tng n do p xut bn trong th tch vt cha

tng ln qu cao vt qua gii hn chu lc ca vt cha nn gy n.

V d : N bnh kh xy trong khi vn chuyn, n ni hi . . .

Hin tng n ha hc : L hin tng chy nhanh xy ra tc thi, thnh phn ha

cht ca cc cht ta ra nng lng to thnh kh nn v c kh nng sinh cng.

V d : N cc cht n nh bom, n . . .

Nhng iu kin vn chuyn an ton:

S rung, lc, va p, ma st v nhng trc trc ca phng tin vn chuyn,

trong qu trnh bc xp l nhng nguy him ch yu khi vn chuyn cc vt liu n.

phng nga nhng nguy him c th xy ra khi bc xp, vn chuyn vt liu n, cn

lu thc hin nhng yu cu c bn sau:

K thut an ton chung khi vn chuyn: khi vn chuyn vt liu n, cn tun

th nhng quy nh l:

Khng vn chuyn vt liu n bng xe t ( xe ben ), t chy kh, xe m t

hoc b, mng; c th vn chuyn bng tu, xe in, thuyn,

Cm vn chuyn kp n, thuc en v thuc n cha nitroefir lng trn cc

rmoc ca t.

Phi c ngi p ti khi vn chuyn trn ng di, ngi p ti phi c kin

thc v vt liu n, c giy php v c bo v nghim ngt.

Phi vn chuyn ring bit trn cc phng tin khc nhau i vi cc vt liu

n khc nhau.

Khng vn chuyn chung vt liu n vi nhin liu, cc bnh cha kh c p

sut ( bnh xy, axtilen ).

Cm vn chuyn ngi chung vi vt liu n v nhin liu.

Vn chuyn bng t: khi vn chuyn vt liu n bng t, phi tun th

nhng quy nh sau:

13

t vn chuyn phi c bng hiu v cm c hiu chuyn ch cht n nguy

him. Khng dng t ang vn chuyn vt liu n sa cha, tip nhin liu, ngoi

tr nhng trng hp tht cn thit.

Khong cch 2 xe cng vn chuyn vt liu n trn ng bng t nht 50m,

i vi ng dc l 300m.

Dng, xe tm thi, ngh qua m phi cch xa cc cng trnh, khu dn c t

nht mt khong cch ti thiu l 200m.

Khi vn chuyn cc kp n, cht n cha nitroefir lng v thuc n en, ti

trng ti a ca t khng c vt qu ti trng cho php, cn theo chiu cao

tnh theo cc hm cha khng c vt qu 2 dy.

Vn chuyn bng xe la v tu, thuyn: khi vn chuyn vt liu n bng xe

la, tu hoc thuyn phi tun th nhng quy nh l:

Toa cha vt liu n phi cch u my t nht 4 toa; kp n phi c ch

cch toa cha thuc n t nht 4 toa v phi cui on tu

u tu xe la phi c b phn thu la, trnh va chm mnh khi dng

Khi ct cc toa cha vt liu n, phi chn.

Toa ch ngi phi cch toa cha vt liu t nht 4 toa.

Tu, thuyn phi c c quan an ton giao thong ng bin kim tra trc

khi cho php vn chuyn.

Bc xp vt liu n: khi bc xp vt liu n, phi bo m:

Bc d vt liu n ch c tin hnh theo s hng dn, ch huy ca ngi c

trch nhim. Bc xp cc hp, ti, thng, hm cha vt liu n nh nhng, trnh va p

v ri. Khng c qung, vt, ko l cc hm, ti vt liu n.

Cc vt liu n khc nhau c bc xp ring bit, kp n c cch xa vt

liu n trn mt khong cch khng th truyn n c.

1.2.2.3 Phng chy cha chy

y l cng tc cc k quan trng v rt cn thit cho mi ngi, mi lc, mi

ni, cho tt c cc ngnh ngh v trong cuc sng hng ngy ca mi chng ta.

Cng tc phng chy t bit quan trng trong nhng lnh vc thm d khai thc,

ch bin, bo qun du kh, khai thc than , sn xut vi, sn, cc ha cht, v

14

chng l nhng cht d chy, n. Chy khng nhng gy thit hi v ti sn, ca ci

m cn gy tn tht tnh mng, nh tr sn xut, gy n nguy him v gy nhim

mi trng sinh thi.

Chy v phn loi chy

Khi nim: chy l nhng phn ng ha hc-oxy ha nhanh vi s ta nhit

ln v to ra nhng sn phm phn hy (kh, hi nc v tro).

Phn loi:

Theo ngun gc pht sinh ra chy ngi ta chia ra: chy ni sinh, chy ngoi

sinh. Chy ngoi sinh l chy c pht sinh do ngun nhit bn ngoi ( ngn la k

bn, s chp in, nhit do ma st). Chy ni sinh c th pht sinnh do t t nng

v t bc chy. Theo bn cht chy v v tr chy ngi ta chia ra: chy m, chy c

ngn la, chy ngm, chy hm l trong c chy m

Theo vt liu chy ngi ta chia chy thnh cc nhm: chy cht rn kim (g,

giy, vi..), chy cht lng (du, nht, m, sn), chy kim loi, chy kh gas, kh m,

chy do chp in.

iu kin cn thit v c ch pht sinh ra chy: gm ba yu t cht chy, cht

oxy ha, v ngun nhit, ba yu t ny phi kt hp vi nhau theo ng t l, vo cng

mt thi im v ti cng mt a im.

Tn ti cht chy c: cht chy, vt liu chy c c th th rn, th lng

hoc th kh. Cht chy rn l nhng cht chy trng thi rn nh g, giy Cht

chy lng l nhng cht chy trng thi lng nh xng, du Cht chy kh l

nhng cht dng th kh nh kh, Propan, Butan

C oxy: cht oxy ha c th l oxi trong khng kh, clo, flo, lu hunh, cc

hp cht mang oxi nh: kalipecmanganat, amoni ntrat, kali clorat. Trong khng kh

oxi chim 21% th tch iu kin bnh thng, khi nng khng kh cn 2-5% s

chy khng th duy tr v s ngng chy.

C ngun nhit: ngun nhit c th l ngn la k bn, s nung nng cao,

nhng tia la pht sinh t cc thit b do ma st, va p, t cc thit b in, do chp

in, do ging, st. Ngun nhit c th to ra do s phng in ca in tnh v in

15

kh quyn, do n. Ngun nhit cn c th l ngun n: do cc qu trnh ha hc, sinh

ha, nn on nhit

Thiu mt trong ba yu t s chy khng th pht sinh v duy tri c. Nhit

t bc chy t l nghch vi p sut t bc chy. Qa trnh chy ch c th xy ra trong

nng tng ng nht nh i vi hn hp kh gas-khng kh nhng nhit t

bc chy khc nhau.

Mt s dng chy ca cc cht chy trong khng kh. Cht dng cc, thi

khi chy c th khng c ngn la nh than cc, cc kim loi kim hoc chy c ngn

la nh g, than nu m chy c mu sc v mi khc nhau. m chy c mu

sng l t trng cho cc vt liu hu c c hm lng cacbon ln hn 60%; m chy

c mu ti l t trng cho vt liu hu c c hm lng ln hn 50% v cc cht v

c khi chy to ra th kh chy c. Cc cht c thnh phn ha hc phc tp khi

chy va to ra ngn la va sinh khi. Qa trnh chy c th hon ton hoc khng

hon ton. Chy khng hon ton cho nhng sn phm c v c th gy n. Vi,

bng, len, than bn thng b chy khng hon ton. Cc cht do cng cho m chy

khng hon ton v to ra nhiu cht c: CO, HCl, NH3 Chy ca hn hp bi, kh

gas thng km theo n.

Nhng nguyn nhn gy chy: khng thn trng, bt cn khi s dng la, lm

cng tc hn. S dng, bo qun nguyn liu d chy khng an ton. S dng in v

thit b in khng ng qui tc phng chy. Cng tc t chc, qun l, iu hnh cha

tt.

Khng thn trng, bt cn khi s dng la, lm cng tc hn. Nhng nguyn

nhn bt cn c th l:Dng la kim tra s r r ca kh gas, du xng hoc cht

lng d chy trong cc thit b cha, ng ng dn. Khng theo di bp khi ang nu

nng, khng theo di qu trnh sy vt liu, dung, giy t; si m qua m bng

bp in, l sy in hoc ra khi nh vn si khi ma lnh m ng; khng ch

khi s dng cc thit b in, lm chy vt tip xc, vt k bn do nung nng cao;

nm, vt tn thuc ba bi hoc khng ng ni qui nh; b tr qu trnh sn xut sinh

la nh hn in, hn gi , cc l t, l nung nu kim loi, gia cng ch bin nha,

vi phm qui nh an ton chy n hoc khng c giy php qui nh.

16

S dng, bo qun nguyn liu d chy khng an ton. Khng cha trong cc

bnh, b kn cc cht kh, lng, rn d chy v c kh nng t bc chy tronng khng

kh; xp t ln ln hoc qu gn nhau gia cc cht c kh nng gy phn ng ha

hc ta nhit..; b tr, xp t cc bnh cha kh c p sut cao gn cc ngun nhit

cao hoc qu gn v tr hn ct; kho cha, ni bo qun cc cht d chy v t bc chy

khng bo m ng yu cu phng chy; d lu chui du m cht ng, mt s ki

loi kim ni m t hoc nc ri bn vo, than cht cht ng m v

thm kh thch hp c th t bc chy; tng tr, bun bn tri php nhin liu v

sng chung vi nhin liu tng tr cng d gy chy nguy him.

S dng in v thit b in khng ng qui tc phng chy. S qu ti khi s

dng thit b in khng ng vi in p, chn tit din dy dn cu ch khng ng

vi cng sut ph ti, do chm in to ngn mch; do pht sinh tia la in trong mi

trng nguy him chy n; tip xc khng tt mi ni dy, cm, cu dao,; do

s dng dng c, chiu sng khng ph hp vi qui nh an ton kho cha hang cht

d chy n hoc do ri, v bong n in trn sn cnh nhin liu n.

Cc nguyn nhn khc gy chy ngoi sinh v ni sinh

Cc nguyn nhn khc gy chy ngoi sinh. Ma st, va p lm bin i c nng thnh

nhit qu nng hoc ta thnh tia la. Phng in ca in tnh v in kh quyn. S t

bc chy ca cc vt dn la c trong thin nhin Chy methane trong ngun t bc

chy xy ra trong hm l v lan truyn. N cc hn hp bi + kh+khng kh hoc n

hi. Tin hnh cng tc n mn khng ng k thut, chy thuc n, Tn la. m

bt la vo vt liu d chy t cc trm nng lng lu ng; cc phng tic giao

thong hoc t cc m chy ln cn. St nh vo cc cng trnh khng bo v chng

st tt v cng trnh lm bng vt liu d chy hoc lm chy nhin, nguyn liu d

chy bn trong. Nhng yu t k thut-a cht- m to ra tnh d chy trong chy

ngm, chy hm m.

Cc nguyn nhn pht sinh chy ni sinh. Tn ti vt liu c kh nng b oxi

ha. S np O2 vo b mt oxi ha ca cc phn t tch t. S thot nhit kh khn t

ngun t nung. S bo ton ba iu kin trn khong thi gian nht nh xy ra qu

17

trnh oxi ha vt liu iu kin nhit thp hoc trung bnh v chuyn thnh pha

chy.

Nhng yu t k thut m - a cht cng ng vai tr quan trng trong vic

pht sinh cc m chy ni sinh.

Phng chy khi thit k v xy dng cng trnh

Khi thit k xy dng cc hng mc cng trnh, ty thuc vo mc ch s

dng v tnh nguy him chy n, phi thc hin mt cch nghim ngt: cc phng

php phng chng chy n. Kh nng s tn con ngi khi c chy mt cch nhanh

chng. Kh nng dp tt m chy mt cch hiu qu.

Quy nh v li thot him. Khong cch ti a t v tr n li thot him gn

nht trong sn xut l 50-75m, trng hp t bit l 100m. Chiu rng ti thiu cho

li thot nn i vi li i v cu thang l 1m, hnh lang l 1.4m, ca l 0.8m. Khong

cch ti thiu t kho l thin cha vt liu d chy n cc cng trnh ph thuc vo

loi vt liu v qui m kho thay i t 6m n 36m. Tt c cc ta nh, cng trnh phi

c t nht mt li thot him cho mi chu vi khng qu 200 m. Tt c cc cng trnh

cao tng (>25m) phi c t nht hai li thot him cho mi chu vi khng qu 200m.

Nhng ta nh cao hn 10m phi khng c t hn mt cu thang bn ngoi trn mi

chu vi 200m bao quanh nh.

Phn chia khu vc, lnh th sn xut: lnh th sn xut ca mi nh my, cng

trnh, phi c chia ra t nht ba khu vc ring bit bng tng chy hoc bng

khong cch an ton chy. l: khu vc lm vic, nh xng, khu cng trnh ph.

Khu vc kho tang, khu vn phng

Nhm ngn nga s lan chy khi c chy. Thm vo , nhng phn xng kho tang

c tnh d chy n phi c b tr cui hng gi ch o trong nm hoc ni

thp, cui dng chy ca song. Trn nhng gin khoan khai thc du kh, khu nh

vn phng c cch ly khi khu vc khoan khai thc v khu my pht in bng cc

ng ho bng thp rng khng nh hn 4m v lnh th hn ch v c lien lc, lu

thong bng cc cu vt cng bng cht khng chy c. Khi khai thc du kh trn

t lin th khong cch t cc ming ging du kh n cc bnh tch, b cha, trm

my pht in >40m, n cc my nn kh, trm nn kh >60m, n v tr t kh thi

18

>100m v phi cui hng gi ch o, n khu nh v lm vic >500m v u

hng gi ch o.

m bo mng li ng giao thng: trn mi lnh th, c quan XN,cn c

mng li ng giao thng rng v thng thong (TCVN 4m) t hai pha nhnm

m bo kh nng lu thng v iu phi cc i cu ha khi dp tt m chy. m

bo ng giao thng t nht t hai pha ca cng trnh cn nhm ngn nga s lan

truyn ca m chy do pht x v i lu nhit ca cc sn phm chy.

Yu cu v cc trang thit b in: khi trang thit b, dng c, ph tng in

trong mi cng trnh ca c quan, XN, phi chn cho chng ph hp vi tnh nguy

him chy n ca mi cng trnh, kho tn. Cc cp dn in t li in n cc thit

b in v n chiu sang phi m bo t mi ni nht, c ng knh tit din phn

dn in ti thiu ln hn sc chu ti khi cng sut thit b, n lm vic ti a, phi

cch li v bo v tt, thng xuyn nhm trch r r, pht ra tia la v t nng qu

mc.

Tt c cc cm bin in t ng phi an ton, t bit i vi nhng cng

trnh nguy him chy - n. Chng phi bo m nhy cn thit theo thit k v lm

vic tt, t ng iu chnh v hn ch in p, cng dng vi cc in cm khc

nhau. Tia la pht sinh t cm bin c phi m bo khng nng lng bc

chy hn nhin liu v kh gas (

cm bin nhit hoc cc u bo chy khi c b tr ti nhng ni c nguy c v

chy n vi mt v v tr ty thuc vo chng loi ca chng v c ni bng dy

dn vi h thng ni t ng v ni vi nhau vi trung tm iu khin, trc thng

xuyn 24/24 gi.

C ba dng u bo chy: u bo chy khi, u bo chy nhit v u bo

chy nh sng. Din tch mt sn m u bo chy kim sot v bo ng khi, nhit

cng nh v tr t chng ph thuc khng nhng vo t tnh bo chy m cn ph

thuc vo chiu cao lp t so vi mt sn lm vic

Trang b h thng phng chy cha chy: phi trang b cc h thng cha chy

theo yu cu quy phm phng chy cha chy ty thuc tnh nhuy him chy n v

chc nng ca cng trnh cng nh cc phng tic cha chy di ng, xe cha chy

chuyn dng cho cc trung tm phng chy ch chy qun huyn.

m bo s s tn ngi v phng chy cha chy: trong mi c quan. XN,

phi c s phng chy cha chy v ni quy phng chy ch chy cng s s

tn, thot him CBCNV.

An ton phng chy khi s dng vn hnh tht b v nhng bin php t chc

hnh chnh

Nhng quy tc an ton chy khi s dng vn hnh:

Vn ht thuc v s dng la: ch c ht thuc v vt tn thuc, dim

qut ng vo ni quy nh, an ton v khng gy nguy him chy cho bt c vt g

chung quanh.

Quy nh v cc cng vic sinh la nguy him: Cc cng vic sinh la nguy

him (hn, ct kim loi, mi...) ch c thc hin theo ng giy php thi gian v qui

nh nh trc c ghi r trong giy php. V d: v tr hn ct phi cch bnh oxi,

axetylen t nht 10m v chng cch nhau t nht 5m, phi che ph tt c cc kt cu d

chy trong bn knh 5m quanh v tr hn bng bao b tm nc nu khng duy chuyn

c. Khng tin hnh hn, ct, mi cc thit b, cc bnh cha, cc ng ng dn

ang c p hoc ang cha nhng cht d chy, n (xng, du, kh gas )

Quy nh v cc cht thi d chy: Tt c nhng cht thi d chy (giy vn,

gi lu nhim du, xng, m ) phi c b ng vo ni quy nh cc thng rc

20

ring bit bng cht khng chy v c np y. Cc cht lng d chy b ln sn

phi c lau sch ngay bng d lu tm nc l. Khng dng xng, du lu, chi

trang thit b in, nhng trang thit b b tr trong cng trnh d chy n. Cc gi lu

nhin liu cng phi cng phi b vo ng ni quy nh.

Quy nh v cnh bo, phng nga: trn cc cng trnh nguy him bo chy

nh kho nguyn liu, kho nguyn vt liu d chy, cc cy xng, cac trm tip t nhin

liu, cc nh my sn xut, ch bin gas, du xng, nh my, XN sn, vi, cc cng

trnh khoan, khai thc du kh, phi c bin cnh bo ln bng ch nn trng

treo nhng ni nguy him chy, c ngi qua li, d thy t xa vi ni dung: CM

LA!, CM HT THUC! v biu tng v tnh nguy him chy (ngn la

trn nn trng).

Quy nh v tng tr, ct cha nhin liu v cht n: khng tng tr, ct cha

nguyn nhin vt liu d chy n k cnh: h thng thng gi, ng c t trong,

my pht, ni hi, l t, nu, Hm l, ng hm, ming hm trong khong cch

nh hi 30m. Khng ct cha nguyn nhin vt liu chy n trong phng, nh ,

vn phng lm vic, Nhng vt dng, phng tin khng cn c s dng na phi

c tr v kho bo qun ng qui nh hoc bin thnh ph thi v phi loi tr ngay

ra khi lnh th XN cng sm cng tt.

Nhng bin php t chc hnh chnh qun tr: phng chy v cha chy tt

nht l nng cao ngha v v trch nhim ca mi cng dn, CB CNV.

Thnh lp i cha chy: trong mi c quan, XN, ty thuc vo quy m va tnh nnguy

him chy, ngi s dng lao ng phi thh lp i cha chy (kim nhim) c

hun luyn k cc phng n chng chy, cu ngi khi chy v nh k hang nm phi

tin hnh tp hun chng chy. Trong thnh phn i cha chy ti chi ca c quan,

XN l nhng thanh nin kha mnh, nhit tnh ca x nghip, cc thnh vin ca i

bo v v ng u l gim c c quan, XN .

21

22

Hnh 1.2.2.1: Tp hun v cng tc phng chy cha chy

Thc hin tuyn truyn, thng tin rng ri: Thc hin tuyn truyn, thng tin

rng ri cho ton th CB-CNV, nhn dn nhng kin thc c bn v phng chy

23

cha chy, cu ngi bng cc hnh thc a dng, phong ph v nh k hang nm,

nht l trc khi bc vo ma kh.

T chc phong tro thi ua bo m an ton phng chy: cn t chc phong

tro thi ua bo m an ton phng chy trong cc b phn ca c quan, trong cc c

quan, XN ca cng ty, ca ngnh, BHng nm cn pht ng phong tro thng an

ton phng chy cha chy trong ton dn, c quan, XN. Pht ng thi ua gn lin

vi cc hnh thc khen thng pht nghim minh. Ngun kinh ph c th trch t cc

ngun ca cng tc phng chy cha chy. n v lm tt cng tc phng chy cha

chy th khen thng; n v lm cha tt cn c bin php kp thi chn chnh v

khc phc. Nhng ni c vi phm cng tc phng chy phi x pht.

T chc cng tc kim tra, gim st: ty thuc vo tnh nguy him ca cng

trnh, ngi chu trch nhim v phng chy cha chy phi ch than kim tra nh

k v t xut ( 1 ln/thng i vi cc cng trnh nguy him chy v 1 ln/6 thng i

vi nhng cng trnh khc). Ni dung kim tra, gim st l phi xem xt:

S hin hu v hu hiu ca cc h thng bo ng v cha chy, cc phng

tin cha chy di ng hoc cm tay.

Tnh trng cc cp in, cc ph kin in cho thp sang, dy tip t.

kn v s r r nhin liu, kh ca cc bnh b cha, ng ng dn, cc

mi ni, cc van.

Nng hi xng, du kh gas ti cc ni ct cha chng trc mi khi hn,

ct, mi trn cc cng trnh nguy him chy (khai thc, ch bin du kh, ti cc trm

tip nhin liu)

Nng gii hn cho php ca hi xng du trong khng ti vng kim tra

phi bo m: nh hn 0.04% i vi xng, nh hn 0.07% i vi du.

Phi ghi nhn cc nhn xt qua mi ln kim tra, gim st vo S phng chy

cha chy ca c quan. Nhng thiu st c pht hin qua cc cng tc trn phi

c khc phc v chn chnh kp thi.

Pht hin v ngn nga cc ngun t bc chy:

Pht hin cc ngun t bc chy: bin php u tin pht hin cc ngung

t bc chy l xem tnh trng m - a cht, cc mt ct b dy va v thi gian tin

24

hnh cc cng tc c so snh vi cc s liu vt l pht sinh cc ngun t bc chy trn

vng m . Bc tip theo l t chc kim tra li tt c cc v tr cho l nguy

him.Cc phng php pht hin m chy ni sinh c thchia thnh bn nhm chnh:

cc phng php cm quan, cc phng php phn tch hoa hc, cc phng php

phn tch vt l, cc phng php a ha khong vt.

Cc phng php cm quan: pht hin chy ni sinh da trn nhng du hiu

bn ngoi, ngha l nh cc c quan cm gic ca con ngi m khng s dng bt k

thit b, dng c xc nh no.

Cc phing php phn tch ha hc: nhng du hiu ca chy ni sinh c

xc nh nh kt qu ly cc mu khng kh, nc, t trong khu vc v phn tch

ha hc

Phng php a ha khong vt: phng php ny l bc tip theo trong

vic nghin cu thnh t nh nghin cu cc khong vt th cp to thnh do qu

trnh oxi hoa trong va.

Cc phng php vt l: Cc phng php ny xc nh s chy ni sinh da

trn cc thng s vt l ph thuc vo trng thi nhit ca mi trng, m khng

kh. Bng nhng dng c chuyn dng.

Theo cc thng s nhn c, ngi ta xy dng cc ng ng a nhit v

khoanh vng ngun t t nng, xy dng tc d v hng tt dn ca cc qu trnh

nhit trong lng t. Tt nht nn s dng kt hp tt c cc phng php pht hin

sm chy ni sinh.

Phng nga v loi tr cc ngun t bc chy: cc bin php nhm phng

nga v loi tr cc ngun t bc chy l: loi b cc vt liu c kh nng b oxi ha,

gim hoc ngn chn s tip xc ca vt liu vi oxi, gim hot tnh ha hc, tc kh

nng oxi ha ca vt liu t bc chy hoc lm lnh khi b nung.

Phng tin v k thut cha chy

Cc nguyn tc cha chy: ty thuc vo nhng c tnh ca vt liu chy v

nhng iu kin chy ngi ta s dng cc phng tin vi c ch dp la khc nhau.

Nhng nguyn tc cha chy c th l:

Lm mt cc vt liu ang chy hoc ngun la.

25

Ngn chn cht chy (nhin liu, kh gas) trn vo m la (bng cch ng

van ng ng, ngt van an ton,)

Ngn nga oxi vi m chy bng kh tr, bt ha hc, bt khng kh

Cch ly v chn ng nhng phn ng dy chuyn ca s chy n bng cc

hydro cacbon halogen ha, bng etyl bromua C2H5Br v tetra flodibrometan hoc

nhng bt cha chy tc ng ng ch.

Cch ly m chy nhm ngn chn kh nng bt la n nhng cng trnh,

vng k cn, chn ng s ly lan m chy. Nguyn tc cha chy ny thng s

dng kt hp trong vic cha chy cc m chy rng

Cc cht cha chy: ng cht m khi tc ng ca chng vo vt ang chy s

lm gim hoc dp tt s chy. Cc cht dng cha chy c th dng:

Lng: nc, tia nc, cc loi dung dch bt.

Kh: CO2, cc halongen,.

Rn: cc loi ha cht kh, ct, bt kh (bt ng ch)

Cc cht cha chy khc nhau vi cc h s mc quan trng (1, 2 v 3) i

vi c ch dp chy c th hin trong bng sau:

CHNG 2: AN TON MI TRNG DU KH

2.1 Cc nguyn tc an tan chung khi lm vic vi LPG

2.1.1 Cc c tnh an ton ca LPG

LPG l mt cht rt d chy v c th n khi hn hp vi khng kh

LPG th kh hi nng hn khng kh, dng kh LPG c th lan xa, tip xc vi

cc ngun la v lan ngc tr li bn hoc chai cha

LPG c th t li trong khng gian kn gy nguy c cao v n v c

Khi cha trong cc bnh v bn kn, LPG thng tn ti dng kh ha lng,

khi hp th nhit t bn ngoi (nh nng, nhit t ngn la, cc ngun nhit

khc) ,p sut bn trong bn hoc chai s tng ln c th gy nguy him cho

thit b v con ngi

2.1.2 Cc nh hng ca LPG i vi sc khe

2.1.2.1Cc nh hng ca LPG ln h h hp

nng thp di 0,1% kh LPG khng phi l cht c hi. 26

nng di 1% LPG khng gy ra triu chng c bit no

Nng LPG cho php lm vic lu di l 0,25%

Nng kh LPG trn 1% c th gy ra chong nh sau vi pht, tuy nhin

khng gy kch thch r rt ln mi v hng

LPG l cht gy ngt. Nng LPG qu cao c th chim ch ca Oxy trong

khng kh v gy ngt. S thiu oxy bt u xy ra khi nng Oxy thp hn

18%.

Cc triu chng khi thiu oxy:

T 12 - 16%: th gp

t 10 - 14%: cm gic mt mi bt thng, ri lon cm xc

t 6 - 10%: nn i v mt kh nng t ch

di 6%: co git v suy h hp, c th dn n t vong

2.1.2.2 Cc nh hng ca LPG ln da

LPG th kh khng c nh hng ln da

LPG lng phun ra di p sut c th gy hin tng bng lnh. Nu bng nh

c th gy t cng, au nhi nh kim chm v nga vng da b bng. Nu

bng nng s c cm gic chy rt, da b bt trng hoc c mu vng. Vng da

b bng b phng gip v c th b hoi th.

2.1.2.3 Cc nh hng ca LPG ln mt

LPG dng hi khng gy cay mt.

LPG lng bn vo mt c th gy ng bng ti mt v gy m

2.1.2.4 Cc nh hng khc

Ngi ta khng ghi nhn c cc nh hng khc, c th LPG khng gy ung th,

khng nh hng n kh nng sinh sn v khng nh hng n thai nhi.

2.1.3 Cch x l cc tai nn khi tip xc vi LPG

2.1.3.1 Nu c ngi b chong khi lm vic trong mi trng LPG

Ngi vo cp cu phi mang y mt n phng c

Nhanh chng a ngi b nn ra ni thong kh

Thc hin thao tc h hp nhn to nu nn nhn b ngng th

27

Thng bo ngay cho nhn vin y t

2.1.3.2 Nu b LPG lng phun vo da

Nhanh chng a ngi b nn ra ngoi, dng nc nh ln vng da b bng

cho n khi ht LPG. Cm lm nng, lau hay phun kh nng ln vng da b

bng.

Nh nhng g (hoc ct ) b qun o v qun nh quanh vng b bng bng

bng vi tit trng.

a ngi b nn n trm y t gn nht.

2.1.3.3 Nu b LPG lng phun vo mt

Nhanh chng a ngi b nn ra ngoi, dng nc nh ln mt cho n khi

ht LPG. Cm lm nng, lau mt.

Bng c hai mt bng bng vi tit trng.

a ngi b nn n trm y t gn nht.

2.2 An ton trong vn hnh h thng chu p lc

2.2.1 Khi nim chung

Cc h thng chit np, s dng LPG l cc h thng kn, cha LPG bo ha

di p sut cao nhit mi trng. T c th thy hai mi nguy him chnh

lin quan n h thng LPG l:

H thng lun c p sut, khi p lc ca mi cht vt qu kh nng chu lc ca bn

cha, ng ng s gy ra n v.

LPG cha bn trong h thng l mi cht c kh nng chy n cao, khi xy ra s c n

hoc r r, LPG thot ra ngoi c th gy ra chy, n dy chuyn rt nguy him.

Chnh v vy, i vi h thng LPG, cc bin php m bo an ton tp trung

vo:

Cc bn cha (bn c nh, xitec, chai cha) v h thng ng phi c thit k,

lp t, nh k nghim th m bo chu c p sut mi cht vi h s an

ton ln nht c th

Qu trnh vn hnh phi thng xuyn theo di, pht hin ngay cc nguy c n

v, r r x l kp thi.

28

Khu vc lm vic phi m bo khng c cc ngun gy tia la, c thng gi

tt trnh LPG t li to thnh hn hp n vi khng kh.

2.2.2 Cc s c lin quan n h thng chu p lc

2.2.2.1 S c n v

Phn loi: c th phn ra lm hai loi n v

Nt : xy ra vi tc chm khi trn h thng xut hin vt nt lm phun mi cht ra

ngoi.

N: xy ra vi tc rt nhanh, h thng b ph hy thnh cc mnh nh v to ra cc

sng n. Va p ca cc mnh bn v sc p ca sng n trong khng kh s gy ra tai

nn cho con ngi v thit b c bit trong cc khng gian kn.

i vi mi cht chy n nh LPG vic mt lng ln mi cht thot ra ngoi

thng to ra cc hin tng chy n km theo.

2.2.2.2 Nguyn nhn

Mi cht bn trong h thng hp th nhit lm p sut tng cao. iu ny c

bit nguy him i vi h thng cha LPG, khi hp th nhit LPG lng s bay hi rt

nhanh, do s chnh lch v th tch gia phn lng v phn hi (1 lt propan lng bay

hi 15OC s to thnh 270 lt kh ) p sut s tng cao nht l khi h thng cha y

LPG lng.

Do khng kh lt vo to thnh hn hp n bn trong h thng. i vi h

thng LPG s c ny hay xy ra khi np kh ln u hoc thng thi khi sa cha.

p sut h thng khng tng tuy nhin bn cha, chai v ng ng b yu i

do n mn, va p, khuyt tt

Hin tng thy kch: Trong h thng ng ng LPG hin tng thy kch

xy ra khi dng cht lng b chn li tc thi. Dng cht lng chy bn trong ng c

qun tnh ca n, khi b chn li mt cch tc thi (v d nh c van chn no b

ng li mt cch t ngt) lc qun tnh ca dng cht lng s chuyn thnh lc sc

(sc thy lc) dng sng, truyn ngc li pha sau gy v ng. Khi xy ra hin

tng thy kch, ng s b rung v c ting ku bt thng.

2.2.2.3. S c r r

Cc nguyn nhn gy nn s c r r bao gm:

29

R r do cc mi ni c tnh trng k thut km.

c thit k khng ng quy cch: mi loi mi ni ph hp vi mt iu kin

nht nh, vic la chn khng ng loi mi ni s lm tng nguy c r r. Ni

chung tt c cc mi ni c th tho c u c nguy c r r cao, v vy ngi

ta hn ch sao cho s lng mi ni loi ny trn h thng ng l nh nht, dng

cc mi ni bng hn cc v tr c th.

Xit khng cht

Mi ni ren, mt bch b lng ra do rung lc trong qu trnh s dng. Hin tng

rung lc khng ch lm lng cc mi ni m cn c th lm cho cc van kha b

m ra mt cch bt thng

Bn cha, ng ng b nt, thng do va chm, n mn, mi mn, do cc

khuyt tt bn trong kim loi.

Do bi bn bm vo b mt np van, mt bch

Do p sut tng qu cao lm cc van an ton m

Do cc sai st trong vn hnh

2.2.3 Cc bin php bo m an ton

H thng phi c thit k mt cch ph hp

Mt s im ng lu .

i vi cc bn cha t c nh:

p sut thit k cc bn cha LPG khng c nh hn 17 bar vi chiu dy

tng thm d phng n mn t nht l 1 mm

Trn bn cha phi c cc c cu an ton cn thit, c th: trn ng np

lng phi c 1 van mt chiu v 1 van chn. ng cp lng ra phi c van

ng nhanh khn cp v mt van ng ngt trc tip pha ngoi. Gas lng

thng c np vo khoang hi

Bn phi c trang b van an ton c kch thc ph hp vi din tch xung

quanh ca bn

Trn bn phi c t nht mt dng c o mc lng, dng c o mc lng cao

nht v mt p k

30

H thng cc van ng khn cp phi c kh nng ng bng tay t xa cng nh

ti im vn hnh v t ng ng khi c tn hiu bo la, r r t cc u d

kh

Mi bn phi c t nht hai v tr ni vo h thng tip t chng st v chng

tnh in. in tr tip t phi nh hn 10 Ohm

i vi xe bn:

Bn cha t trn xe c yu cu thit k nh i vi bn cha c nh, ngoi ra

cn thm mt s yu cu b sung:

Lng lng np vo bn khng c vt qu 90% dung tch bn

Nu dung tch bn ln hn 10.000 lt, bn phi c mt hoc nhiu vch ngn .

Dung tch mi khoang khng c vt qu 7500 lt

Khi thit k bn, ngoi p sut cht lng ly bng 17 bar, ngi ta cn phi tnh

ti c ti trng ng ca xe

Bn cha bt buc phi c nhit k

Xe bn phi c dy ni t

i vi cc ng :

Trn cc ng hi v ng lng, gia 2 van chn phi c van x an ton c p sut

t bng 80% p sut th ca h thng.

Hin ti, cha c tiu chun Vit nam v p sut thit k cho h thng ng, c

th tham kho quy nh ca M (NFPA 58 iu 3-2.10.2) nh sau:

ng c p sut cao hn p sut ca bn (ng nhp lng, ng y ca bm lng)

thit k p sut 24 bar

ng lng khng ni vi u y ca bm, cc ng hi lm vic p sut ln

hn 9 bar (ng hi ni vi bn pha trc van gim p) thit k p sut 17 bar

ng hi lm vic p sut nh hn 9 bar (pha sau van gim p) thit k p

sut 9 bar

H thng phi c kim tra, theo di mt cch thng xuyn kp thi pht hin

cc khuyt tt, c bin php x l bo dng kp thi.

31

Trm np phi c k hoch quy nh chi tit cng tc kim tra, bo dng nh k tt

c cc thit b trong trm m bo iu kin an ton. Sau y l mt s lch biu

mang tnh gi

i vi cc thit b ph tr

Bng 2.5.1 Kim tra bo dng thit b ph tr

Tn thit b Bin php kim tra, bo dng Thi gian

thc hin Cc van ng

khn cp

Kim tra kh nng lm vic Hng tun

H thng nc

ti lm mt

Chy th, kim tra m bo h thng c th ti

ton b din tch b mt cc bn. Sa cha v thay

th cc vi phun b tc hoc b hng

Hng qy

Kim tra kh nng lm vic Hng nm Cc thit b bo r

r (Gas detector)

Kim tra kh nng lm vic Theo yu cu

ca nh ch

to

H thng bn cha, thit b np, ng ng

Bng 2.5.2 Kim tra bo dng h thng bn cha, thit b np, ng ng

Hng mc kim tra Bin php kim tra, bo dng Thi gian thc

hinKim tra thng xuyn

(S dng danh mc cu

hi kim tra)

Kim tra pht hin cc hin tng h hng r r

sa cha kp thi

Hng ngy

Kim tra hng thng Kim tra m bo cc van kha tnh trng

k thut tt (tay van ng m nh nhng, khng

c r r, n mn trn thn van, mt bch, mi ni)

. Kim tra van an ton (l thot nc khng b

tc, l xo v van khng b n mn) . Kim tra

tnh trng n mn ca ng ng Kim tra cc

u np pht hin cc biu hin h hng, n

mn hay x h.

Hng thng

32

Kim tra hng nm Kim nh li p k, nhit k . Kim tra kh

nng lm vic ca h thng bo ng khi mc

lng qu cao. Kim tra bng mt tnh trng k

thut bn. Kim tra tnh trng k thut ca nn

mng, chn bn

Hng nm

Khm xt ton b cc

bn v h thng ng

Kim tra bn trong, bn ngoi. Siu m kim tra

chiu dy

3 nm/ln(do

c quan ng

kim thc hin) Khm xt ton b v th

thy lc cc bn v h

thng ng

Kim tra bn trong, bn ngoi. Siu m kim tra

chiu dy. Th thy lc

6 nm/ln(do

c quan ng

kim thc hin)

Qu trnh vn hnh phi m bo cc nguyn tc an ton c bn khi lm vic

vi LPG

Cch ly LPG khi tt c cc ngun la trn v cc ngun gy tia la.

Trong qu trnh sang chit, s dng cc chai, bn cha cn c ni t trnh in

tch tnh in c th gy tia la

Khu vc c LPG phi c bin bo cm la, cm ht thuc

Lun gi cho khu vc lm vic sch s, khng c cc vt liu d chy

Yu cu c bn i vi khu vc tn tr v np kh LPG

Phi c thng gi tt, h thng thng gi phi l loi khng gy tia la trong

qu trnh hot ng.

H thng in phi m bo y cc yu cu v phng n v v an ton

Li i li v cc ca thot him phi thong, khng c cc vt chn

Phi lp t cc thit b bo la v bo r r

Yu cu c bn khi s dng chai LPG

S dng s lng LPG t nht c th. Chai phi t trong khu vc c thng

gi tt

Khi khng s dng, chai phi c nt bo v van

Chai phi c t v tr ng, c kp cht chng ng.

33

Khng m van chai khi tay c du, m

Dng van gim p ph hp.

Thit b s dng ga phi l loi ph hp, m bo cc yu cu an ton.

Ch m van chai bng tay, khng s dng bt k dng c no khc m.

Thng xuyn kim tra tnh trng chai kp thi pht hin cc du hiu mp

mo, r st, r r. Khng s dng chai nu pht hin cc biu hin h hng

Lun gi van chai sch s, c bit l khng c nc v du m

Khi s dng kh, lun m hon ton van chai

Khng chai b ri, va p vo cc vt rn

Khng nm vo tay van khi nhc chai

li mt t kh sau khi dng chai ( ngi np chai c th nhn bit loi kh)

Khng s dng chai vo bt k mc ch no khc (nh lm con ln, bc k

v.v.)

Trang b thit b PCCC

Mt s im cn ch : Khi np LPG t tu vo bn (theo quy nh ca

NFPA58)

Trong vng bn knh 30,5 m t cu tu khng c c cc phng tin vn ti khc,

cc thit b in cm tay, bnh cha kh nn, cha cht chy

Ch nhng ngi c trch nhim c mt trong khu vc nhp ga

Khi xut ga cho xe bn

Xe phi hng v pha c ng thot thch hp (m bo cho xe khng phi li

khi thot i), ci phanh, ngt cng tc, ct c quy v chn bnh xe trc khi giao hng.

Phi ni t dy ni t ca xe trc khi ni ng.

Ngi li xe hoc ngi chu trch nhim giao nhn hng khng c i ra ngoi trong

sut thi gian giao hng

Phi lun lun c ngi trng coi xe trong qu trnh np

Phi m bo rng thit b np, xe bn tnh trng k thut tt trc khi np.

ng nay van np khi mc np cn thit. Khi theo di mc np bng thit b bo

mc lng ti a (fixed liquid gauge), cn thc hin quy trnh sau:

34

Phi mang gng tay bo h khi vn hnh thit b bo mc lng ti a

M vt xem lng trn thit b bo mc lng ti a khi bn np c khong 50% sc

cha. Khi thy lng thot ra t thit b bo mc lng ti a, ng ngayvan np.

ng kn vt xem lng

Phi thc hin ng quy trnh x e trc khi np v x kh trong ng mm sau khi np

Nu sau khi ngt ng mm m vn thy ga thot ra t ng np ca xe tc l van mt

chiu gn trn xe bn b hng. Bin php x l nh sau:

Ni ng mm tr li, np thm mt cht lng dng dng mi cht lm sch van mt

chiu. Nu van vn khng kn, dng nt bt kn u np ca xe. Thng bo cho ngi

c trch nhim x l

Trc khi kt thc cng vic phi tin hnh kim tra m bo van bn c

kha, ng mm c bo qun cn thn, cc thit b in c ngt khi ngun

v.v.

Khi np ga vo chai

Ch np kh vo cc chai t cc yu cu an ton, khng c np kh vo cc chai c

cc biu hin sau:

C biu hin h hng c hc: phng, mp, vt xc, vt c v.v.

C hin tng b n mn

Tnh trng chn , tay xch khng m bo

Tnh trng van khng tt

Ch v s ng trn chai khng ng hoc khng r

Chai qu thi hn khm nghim

Chai c biu hin b nh hng ca ha hon

Np theo ng trng lng quy nh

Sai s np cho php nh sau:

Bng 2.5.3 Sai s cho php khi np cc loi bhh LPG

Loi chai Sai s np (kg) 6 -7 kg +0,1/-0 kg9 - 13 kg +0,2/-0 kgT 45 kg +0,4/-0 kg

35

Ngng nay qu trnh np nu pht hin cc hin tng bt thng hay cc h hng gy

ra r r kh trong h thng.

Chai sau khi np phi c kim tra li v: trng lng np v kn

Khi x l cc chai qu y hoc khng m bo kn khng c x trc tip ra

ngoi tri m phi c h thng thu hi kh.

Cc nguyn tc an ton khi lm vic bn trong cc bn cha

Trc khi lm vic phi c giy php lm vic c ch k ca ngi c trch nhim

Trong qu trnh lm vic phi c ngi canh chng bn ngoi bn vi y thit b

th nhn to. Gia ngi lm vic bn trong v bn ngoi bn phi c phng tin lin

lc thch hp.

Cc dng c, phng tin lm vic bn trong bn phi l loi khng pht sinh tia

la. n chiu sng phi l loi phng n c in p khng qu 12V.

Phi phn tch khng kh trc khi lm vic. C th tham kho bng sau y

v cc yu cu i vi thnh phn kh khi lm vic bn trong bn:

Bng 2.5.4: Cc nguyn tc an ton khi lm vic bn trong cc bn cha

Cc iu kin ca mi trng bn trong bn T l oxy trong khng kh bn trong bn

Nh hn 19,5% Ln hn hoc bng

19,5 % Phn trm kh chy so vi gii hn

chy di (%LFL)

> 20% Khng c vo Khng c vo

T 11%

n

20%

C th chui vo bn

vi thit b th. Ch

thc hin cc thao

tc kim tra

Mang thit b th khi

cn thit phi chui

vo bn kim tra

T 2%

n

10%

C th chui vo bn

vi thit b th. Ch

thc hin cc thao

tc sa cha, bo tr

C th chui vo bn

vi thit b th. Ch

thc hin cc thao tc

sa cha, bo tr

36

khng gy tia la

(cold work)

khng gy tia la

(cold work)

Nh

hn 2%

C th chui vo bn

vi thit b th. C

th thc hin tt c

cc thao tc bo tr,

sa cha (hot work

v cold work)

Khng cn thit b

th khi chui vo bn.

C th thc hin tt

c cc thao tc bo

tr, sa cha (hot

work v cold work)

2.2.4 Mt s ha cht s dng trong nghnh cng nghip kh

Methanol cht chng ng

Odoran (Mercaptan) cht to mi

Ha cht chng n mn (Nalco)

Methane + Propan + Butan + Condensat + Hydrogen Sulfide cc sn phm kh.

Sn chng r thit b;

Xng du nht

2.2.4.1 Tnh cht c hi, nguy him ca ha cht

Tt c cc sn phm v ha cht s dng trong cng nghip kh v cc sn

phm trong qu trnh sn xut u c th gy c hi cho ngi v nhim mi trng

xung quanh nu khng c cc bin php an ton trong qu trnh s dng, lu gi v

vn chuyn.

Ty theo tnh cht ca mi loi ha cht m chng c th xm nhp vo c th

theo 3 con ng khc nhau nh ng h hp, ng tiu ha v qua da. Khi vo c

th chng c th gy tn hi ton thn (nh hng n c quan to mu nh bnh bch

hu, ung th mu) hoc nh hng cc b nh vim phi, ung th phi hay vim

lot da.....

c bit cc sn phm trong qu trnh sn xut nh propan, butan, condensat gy bng

lnh nu bn vo da.

2.2.4.1 Cc quy nh an ton ha cht

Khi s dng:

37

Phi kim tra cc thng tin ca nh cung cp ha cht nh: phn loi, nh gi,

nh du, dn nhn .

Hiu r ti liu hng dn, qui trnh lm vic, tnh cht c hi, cch phng

nga v cch s cp cu trong trng hp ng c hoc s c.

Lm vic theo ng qui trnh hng dn ca nh cung cp.

Tt c cc h s ti liu, cc thng tin v ha cht phi c gn ni lm vic

vi ngn ng d c d hiu.

Phi bit v tr vi nc sch gn nht ra khi ho cht bn, vo ngi,

vo mt hoc mt

Mi thng ha cht phi c dn nhn, nh du ph hp.

S dng phng tin bo v c nhn ph hp cho tng loi ha cht nh:

Dng khu trang, mt n phng c hoc thit b th i vi ha cht c

hi d bay hi.

S dng qun o, gng tay, ng chng ha cht i vi ha cht c kh

nng gy bng, kch thch da.

i vi ha cht d chy n: trong qu trnh lm vic phi p dng cc

bin php phng chng chy n ph hp nh cch ly ngun nhit, ngun

la, ni lm vic phi thng thong

Khng vo cc khu vc c lu tr ha cht c hi khi khng cn thit

Cm ht dung dch ha cht c bng ming.

Khng n ung, ht thuc, ngh ngi ti ni c ha cht nguy him c hi.

Khng lm vic, tip xc khi mc bnh d ng vi ha cht.

Khi lu tr trong kho:

Cc thng cha khng c r r, han r v phi c sp xp hp l, khng cn

tr gy vp ng.

Mi loi phi c qui nh, nh du, dn nhn y .

Thng xuyn cp nht s lng ha cht trong kho vo s.

Khng cc ha cht c tnh tng k gn nhau, khng cc ha cht d

chy n gn cc ha cht duy tr s chy (xy, cht nh xy).

38

Ni c ha cht nguy him, c hi phi c bn hng dn qui cch s dng,

bo qun, vn chuyn an ton v c t v tr d thy, d c.

Ngi khng c trch nhim khng c vo kho ha cht.

Cm n, ung, t hi, ng, ngh ngi trong kho cha ha cht.

Ch nn lu gi s lng ha cht cn thit cho hot ng.

Khi vn chuyn:

trnh v tt nht s dng cc hnh thc ng dn, bng ti, xe cn cu, xe y

2 bnh, xe nng, xe ct kt;

Nu s dng ng dn phi m bo h thng ng khng r r;

Vn chuyn cht lng d chy phi m bo thng gi tt vi nhng thng cha

tip t v c ai;

Khi vn chuyn ha cht trong cc bnh chu p lc phi xp chng thnh c lt n

hoc cao su v t cc van v mt pha, cc van phi c y bng np chp c

chng buc chc chn. Nu xp ng th ch xp 1 hng, nu xp nm th phi xp thp

hn thnh xe.

Hy b ha cht:

Phi thng xuyn kim tra v thi b cc ha cht khng cn gi tr s dng,

vic thi b ha cht phi m bo khng gy c hi cho ngi v mi trng xung

quanh, phi tun theo cc vn bn php quy k thut hin hnh i vi loi ha cht c

th .

Cc thng cha ha cht c hi nguy him trc khi b i phi x l trit

tnh c hi .

Rc thi trong qu trnh hot ng sn xut c lin quan n ha cht cng phi

c x l bng cc bin php k thut hp l trc khi thi ra ngoi mi trng.

ng cu s c tran ha cht va bao v mi trng:

Ti cc phn xng phi xy dng ng cu khn khp cho trng hp tran

ha cht.

T chc chc thc tp phng n trn ha cht theo ng nh k v k

hoch ra.

Khc phuc hu qua va thc hin cac bin phap bao v mi trng.

39

2.3 An ton trong vn hnh , bo dng nh my x l kh Dinh C

Nhng bin bo cn lu khi vo nh my

Hnh 2.3.1: H thng bin bo an ton bo h lao ng

Ni quy ra vo:

Khng phn s min vo,

Khi vo phi c Giy php do BG n v lin quan cp,

Khi vo phi eo ph hiu v c bo h lao ng y ,

Khng em theo cc vt dng, vt liu c kh nng gy la nh: v kh, dim qut,

ha cht, in thoi di ng, my nh, my quay phim, thit b in, ng c,

Cm ht thuc v cc hot ng to la,

Khng t do i li

Khng t tin tc ng vo thit b

Mi hot ng phi theo hng dn ca cn b vn hnh

Ni quy xe ra vo:

Khng cho cc loi xe c ng c vo

Trng hp bt buc phi cho xe vo, cn tun th cc quy inh sau:

C Giy php do BG n v lien quan cp.

Li xe phi trnh by r mc ch a xe vo.

40

Tnh trng ca xe m bo an ton giao thng v an ton phng chy cha

chy.

Xe c np chp dp tn la ti ng x.

Tt in i, radio v cc thit b in t khc trn xe.

Trn xe khng mang theo dim qut, cc vt liu hoc dng c c kh nng

nh la hoc gy chy n.

Ni quy phng chy cha chy:

Khng ht thuc v cc hot ng gy la.

Khng em theo cc vt dng, vt liu c kh nng gy la nh: v kh, dim

qut, ha cht, in thoi di ng, my nh, my quay phim, thit b in, ng

c,

Khng i giy inh

Nm bt hiu lnh bo ng va cc li thot nguy him.

Ni quy lm vic:

Tun th ni quy ra vo.

C giy chng nhn qua hng dn an ton v BHL do Phng AT-CL cp.

Khng ht thuc, khng nu nng.

Khng lm mt v sinh mi trng.

Khng ung ru hoc dng cht kch thch trong khi lm vic.

Khng u , khng nh bi, chi c hoc nm ng trong gi lm vic.

Khng lm vic ring hoc t b v tr lm vic.

Mi cng vic nguy him u phi c quy trnh v giy php lm vic.

Ngi thc hin cng vic phi tun th quy trnh k thut v cc yu cu trong

giy php duyt.

Trang b bo h lao ng y v eo ph hiu khi lm vic.

Khng c nhim v tuyt i khng t tin tc ng vo h thng.

Nu thy nguy c khng an ton hoc c s c, tai nn phi cp bo ngay

cho cp trn hoc cn b vn hnh.

2.3.1 Cc nguy him trong vn hnh41

Tt c mi ngi, khi i vo khu vc vn hnh (nh my, trm phn phi, kho

cng ) tc l i vo vng nguy him, lun thng trc yu t nguy him v

chy n do nguyn liu v sn phm u l cc Hydrocarbon CH, sn sng bc chy

khi b r r ra ngoi khng kh nng 5-15% v gp ngun nhit (tia la, ngn la

).

i vi nhng ngi phi lm vic lin quan n vn hnh, bo dng u

phi chu nhng yu t nguy him v ri ro ty thuc vo tng cng vic nh:

Lm vic vi ha cht (x l, bo qun, vn chuyn): chu nguy him c hi, b nh

hng h h hp, thn kinh .

Lm vic trn cao (kim tra, bo dng thit b): C th b ri.

Lm vic trong khng gian hn hp (kim tra, bo dng cc bnh cng ngh) thiu

khng kh, chu kh c gy tc th, b c hi h hp, thn kinh .

Lm vic vi cc cng c/thit b c kh: c cc nguy him v li, ko, ct, va p

t cc b phn truyn ng.

Lm vic khu my pht in, my nn: chu ting n, rung.

2.3.2 Cc qui nh an ton

2.3.2.1 Vn hnh thit b

. Ch nhng ngi c hun luyn v vn hnh thit b, bin php lm

vic an ton v cc qui nh v AT-VSL mi c tham gia vn hnh thit b.

Ngi vn hnh thit b phi tun th ng qui trnh k thut, bin php lm

vic an ton, bin php phng nga, bin php x l khi c s c v cc qui nh khc

ca Cng ty hoc ca n v sn xut v cng tc vn hnh.

Khng vn hnh thit b thiu an ton nh: Thit b trc trc, hng hc, qu

ti, r r, thng s vn hnh vt gii hn cho php; thiu c cu bo v hoc bn thn

thit b ang nm trong vng nguy him ca hot ng no .

Khng vn hnh cc thit b nu vic gy mt an ton cho mt phn hoc

ton b dy chuyn sn xut.

Ngi vn hnh c trch nhim treo bin cnh bo (cn thit th phi kha, c

lp thit b) nu pht hin thit b trong tnh trng khng an ton

2.3.2.2 Bo dng, sa cha, xy dng, lp t42

Ch nhng ngi c hun luyn v qui trnh lm vic, bin php lm vic an

ton v cc qui nh v AT-VSL mi c thc hin bo dng, sa cha, xy dng,

lp t.

Ngi thc hin cng vic phi s dng thit b, dng c an ton v phng

tin bo v ph hp vi tng cng vic c th.

Ngi thc hin cng vic phi lm vic theo ng qui trnh k thut, bin

php m bo an ton cng nh cc qui nh v AT-VSL khc.

i vi cng vic nguy him thi phai co phiu anh gia rui rui ro va thc hin

cac cac bin phap kim soat rui ro, cac cng vic khac tun thu qui trnh cp giy php

lm vic.

Trong khi lm vic hoc sau khi kt thc cng vic, nu thy thit b hoc khu

vc lm vic khng an ton th ngi thc hin cng vic phi c bin php x l

ngay. Nu khng x l c, ngi thc hin cng vic phi treo bin cnh bo, cch

ly khu vc ng thi bo co cp trn v thng bo cho cc bn lin quan.

2.3.2.3 Lm vic trong vng nguy him

Mi hot ng trong vng nguy him (k c vic i vo vng nguy him) phi

c bo trc cho ngi ph trch khu vc v ch tin hnh khi c ngi ph trch

khu vc cho php.

Ngi ph trch khu vc c trch nhim ph bin cho ngi ln u i vo

khu vc nguy him: Yu t nguy him, c hi trong khu vc; cc kh nng nguy him

xy ra, li thot him, v tr cc phng tin an ton, s cu. Hng dn bin php

phng v x l khi s c, tai nn xy ra.

Ti mi vng nguy him phi c du hiu thng bo: Khong cch an ton,

cc yu t nguy him. Nim yt bng hng dn cch phng nga v cch x l khi c

s c, tai nn.

Ngi i vo vng nguy him ti thiu phi mang giy, m, qun o bo h

lao ng, ngoi ra cn mang thm cc phng tin bo v khc ph hp vi tnh cht

nguy him ca khu vc, v d nh: Qun o, giy ng chng ha cht, mt n th, knh

an ton, bt tai chng n

2.3.3 Hot ng trong vng nguy him chy, n

43

Khng t em vo vng nguy him chy n cc vt t, vt liu, thit b,

dng c c kh nng sinh la, sinh nhit hoc d bt chy.

Cm cc hot ng sinh la nh: Ht thuc, nu nng, t c rc, chp nh,

hn, ct.

Nu bt buc phi thc hin cng vic lin quan ti la/nhit nh hn, ct, mi

kim loi th:

Ch nhng ngi c nhim v, c tay ngh mi c thc hin cng vic hn,

ct.

Ch tin hnh khi c ngi ph trch khu vc cho php, cp Giy php

lm vic nng trc khi trin khai cng vic v khng nh c lp thit b

hoc c lp vng nguy him.

Phi chun b bnh cha chy ngay ti ni hn ct

S dng PTBVCN ph hp nh knh hn, gng tay

2.3.4 An ton c kh

Trc khi vn hnh phi kim tra cc thit b c kh bo m c c cu

phng nga ph hp vi c im v yu cu an ton ca thit b, nh:

Che chn b phn nguy him trnh va p, vng, bn, li cun, ct

C cu dng khn cp.

H thng van an ton, ng h o nhit , p sut, lu lng, nhin liu

Tn hiu cnh bo nguy him hoc ch dn vn hnh an ton

Ni t cc thit b mang in.

Khng t tho b hoc lm mt cng dng ca cc b phn che chn.

Qun o, u tc phi gn gng khng b cun vo cc b phn chuyn

ng ca my.

Thit b c kh phi c lp t trn mt bng kh ro, vng chc khng d

trn trt hoc sp .

Thit b ny phi nm ngoi vng nguy him ca thit b kia, nu khng

ch th phi coi vng nguy him c din tch v yu t nguy him ca 2 vng gp li.

44

Thit b c kh phi c bo dng nh k, sa cha kp thi khi c hng

hc phng tai nn, s c bt ng xy ra.

2.3.5 Lm vic trn cao

Khi lm vic trn cao t 2m tr ln, ngoi vic phi mang qun o, giy, m

bo h lao ng, phi eo dy an ton v mc vo ni chc chn.

Kim tra thang, gin do, sn thao tc, lan can/ro chn bo m chc chn

trc khi tin hnh cng vic trn cao.

Khi ln, xung v di chuyn theo ng tuyn qui nh. Nghim cm leo

tro, i li ty tin (nh i trn mt tng, mt dm, tro qua lan can, u bm vo dy

treo ln, xung).

Ch s dng nhng thang, dn gio, sn cng tc m yu cu v an ton (phi

chc chn, c neo gi, khng mc i, thang di khng qu 5m).

Khng lm vic trn cao khi cm thy khng tnh to, khng c nh sng,

khi c ma to, ging bo, gi mnh t cp 5 tr ln.

Khng c qu 1 ngi lm vic trn thang.

Khng dng thang, gin gio bng kim loi trong iu kin in c th chm

vo thang.

Khng bn, du m hoc cht trn khc dnh vo thang, gin gio. Ti

thiu 6 thng/ln kim tra chu lc ca thang, gin gio bng cch treo vt nng

hoc th vt nng (t 110-250kg) ln thang, gin gio.

2.3.6 Lm vic trong khu vc khng gian hn hp va khng gian kn

Khi lm vic trong khu vc kn, phi c t 2 ngi tr ln. t nht c 1 ngi

canh chng ngoi ca sn sng gip ngi b nn.

Lp danh sach ngi ra vao khng gian kin, ghi ro thi gian vao, thi gian ra

va ky xac nhn.

Trc khi vo lm vic trong khu vc kn, phi o kim tra nng xy, kh

c, kh chy va kim tra thng xuyn 01h/ ln.

Nu khu vc kn l mt thit b, bnh, bn hoc kho, hm cha thng vi cc

phn khc ca cng trnh c cha cc cht nguy him, c hi th phi cch ly khu vc

kn trc khi cho ngi vo lm vic.

45

Khng vo khu vc kn nu nng kh c >10ppm, xy >22% hoc 5% LEL. Trng hp bt buc phi vo th phi eo bnh th v cc trang

thit b bo v khc.

Ngi i vo khu vc kn nu cn phi buc 1 si dy ngang tht lng, u

dy lun ra ngoi ngi canh chng ngoi ca gi. Khi ngi bn trong gp nguy

him, phi git dy ngi canh chng bit ko nn nhn ra.

2.3.7 Dng c cm tay

Ch s dng nhng dng c cm tay ng qui cch, m bo cc yu cu v an

ton v k thut.

i vi dng c cm tay s dng kh nn, kh chy hoc ngun in, trc khi

s dng phi kim tra cc ng dn hi, u ni ng, kim tra r r in

Ngt ngun kh hoc in ra khi dng c khi khng s dng.

Bo qun m bo dng c lun trong iu kin hot ng tt v an ton cho

ngi s dng.

2.3.8 Tng tr, bo qun, vn chuyn thit b vt t, vt liu

Thit b, vt liu, vt t phi c sp xp gn gng, khng cn tr li i hoc

d gy vp ng.

Nu xp chng th vt c trng lng nh phi nm trn vt c trng lng

ln v m bo khng gy sp, .

Nu t trn gi , phi m bo gi vng chc.

Khng cc vt qu nng (t 20kg tr ln) hoc cc bnh, chai, hp cha

cht c hi v d v cao trn 1,5m.

Cc vt trn hoc d ln, trt phi c chn hoc c dy buc nh v.

Cc chai kh phi c xp ng, c mi che, c gi kp v dy buc an ton.

Khng thit b in trn sn nh m t.

Thit b, vt t, vt liu nguy him c hi phi c ti ni d nhn, d

ly, c nhn mc ghi r tn hng, tnh cht nguy him.

Khng cc phuy xng, du, bnh kh chy n nh xy, axetylen,

cacbuahydro, hydrov cc vt liu d chy n khc trong kho kn m phi ni

c mi che nng, thng thong, cch xa ngun la/nhit.

46

Tuyt i khng ht thuc, nu nng, t rc hoc c cc hot ng gy la

khc trong kho hoc ni tng tr vt liu, thit b.

Phi trang b phng tin phng chy, cha chy cho kho bo qun thit b,

vt t d chy, n.

Khi vn chuyn cc bnh kh nn, kh ha tan hay kh ha lng phi xp chng

thnh c lt n hoc cao su v t van v 1 pha, cc van phi c y bng np

chp, c chng buc chc chn. Nu xp ng th ch xp 1 tng, gia cc bnh

khng chn lt bng vt liu d chy. Nu xp nm th phi xp thp hn thnh xe.

Xe vn chuyn cht lng d chy phi c dy tip t.

2.3.9 H thng chng st

in tr ni t ca h thng chng st phi c kim tra t nht 2 ln/nm

vo trc ma ma v u ma kh.

Cc im c in tr ni t >10 phi c x l t c gi tr

24-April-03

KHU V? C VAN

PH NG

C? NG THO T HI? M

C? NG THO T HI? M

C? NG THOT HI?M

C? NG CHNH

P H NG I? U KH I? N

48

Hnh 2.3.1 S li thot him

2.3.11 Thng bo va iu tra tai nn, s c

Nu pht hin tai nn, s c hoc nguy c mt an ton, phi tm cch x l

cu ngi b nn hoc ngn chn hu qu. Nu khng c kh nng x l phi lp tc

bo cho nhng ngi xung quanh va trng ca vn hanh bit.

Mi tai nn, s c v nguy c mt an ton phi c iu tra, lm r nguyn

nhn v rt ra bi hc kinh nghim theo theo ung quy inh.

Mi tai nn s c v nguy c mt an ton phi c x l, khc phc.

Tu theo tai nn s c ln hay nh m phm vi thng bo, iu tra c thc

hin cc cp, mc khc nhau t cp X nghip n Cng ty hoc cc Ban/Ngnh

a phng.

2.3.12 H thng bo ng, cha chy, cu thng

Hp bo ng, dng c cu thng, bnh cu ha, h thng cu ha bng

nc/bt; cc u d kh/la/khi/nhit phi lun trong tnh trng hot ng tt,

y v s lng v m bo v cht lng, sn sng ng cu s c.

Ti mi vng nguy him phi t cc bnh cu ha (nu cn phi b tr hng

nc cu ha v vi phun, ct dp la), hp cu thng ph hp vi tnh cht nguy

him ca vng.

Hp bo ng, dng c cu thng, phng tin cha chy phi c ti

ni d nhn, d ly

Tuyt i khng dng dng c cu thng v phng tin cha chy cho mc

ch khc ngoi mc ch cu thng v cha chy.

49

2.3.13 Gii thiu lc lng, phng tin phnng chy cha chy trn cng trnh kh

Ti Nh my x l kh Dinh C v Cng PV GAS Vng Tu trong cc ca vn hnh

u bin ch 01 tiu i PCCC lm vic theo ca; cc thit b PCCC c trang b nh

sau:

Bng 2.2.2: Phng tin cha chy trn cng trnh kh

TT Tn thit b a im

Nh my GPPCng PV GAS

Vng TuI Thit b cnh bo1 u d kh x x2 u d la x x3 u bo nhit x x4 u bo khi x x5 Cc nt nhn khn cp, loa x xII Thit b cha chy 1 H thng cha chy t ng

bng nc

x x

2 H thng cha chy t ng

bng CO2

x

3 H thng cha chy t ng

bng bt (Foam)

x x

4 Cc tr nc cha chy (hy

drant), Sng phun Monitor

x x

5 Bnh cha chy CO2, bnh

bt xch tay, xe y b v

Foam

x x

6 Xe cha chy 1 xe 1 xe

2.3.13.1 B phn phng chy cha chy

ti Dinh C

Pht hin nguy c chy n:

Cc nguy c gy ra chy n c pht

hin nh cc u cm bin: cm bin kh,

cm bin nhit, cm bin khi, cm bin 50

la. Cc u cm bin nhit, khi b tr trong phng iu khin, nh t my pht in,

trm bm v cc cng trnh ph tr khc ca nh my. Cc b cm bin kh, la b tr

quanh cc thit b cng ngh; cc b cm bin cn b tr trn cng phn vng kim sot

c th v trc tip gim st nguy c chy n trong vng . Cc tn hiu thu c t

cc u cm bin c truyn v v th hin trn panel iu khin ca h thng phng

chng chy n ca phng iu khin trung tm. Panel iu khin t ng x l cc tn

hiu cm bin ny xc nh vng c nguy c chy n ng thi thc hin cc lnh

sau:

Nh my c thit k h thng bo chy, h thng cha chy v h thng

pht hin kh (F&G). H thng ny lin kt vi h thng dng khn cp ESD m bo

an ton cho Nh my.

H thng pht hin chy, r r kh gm:

u d la: 51 ci

u d nhit: 23 ci

u d khi: 28 ci

u d kh: 90 ci

n chp: 09 ci

Ci bo ng: 02 ci

u d lng: 01 dy

Hnh 2.3.4 H thng my pht hin chy, r r kh

Khi chy:

ng van c lp vng chy n v x kh ra uc t.

M van x nc, CO2 hoc bt vo vng c chy n

T ng kch hot my bm cha chy, khi p lc dng thp.

Bo ng bng ci, n chp vng c chy n v phng iu khin.

51

Hnh 2.3.5 B tr ng ng phng chy cha chy trn bn cha LPG

2.3.13.2 H thng cha chy

H thng cha chy bng nc c thit k cha chy bao gm: b cha

nc 2800 m3, h thng ng dn nc cu h, cc tr vi phun nc, cc bm cu ha.

H thng cha chy bng CO2 gm h thng iu khin t ng kch hot

bng ng ng v h thng phn b bnh cha chy CO2 p sut 158 bar ti cc v tr

thit yu.

Bnh cha nit vi p sut 20 bar dng iu khin m cc vn ca h thng

CO2 thc hin vic cha chy theo vng.

H thng ng ng, van v cc vi phun, khi c chy n xy ra cc van trn

t kch hot panel iu khin v vic cha chy c thc hin t ng.

Cha chy bng bt c thit k cha chy cho bn cha condensate, h

thng ny gm mt bnh cha cht to bt, h thng ng ng dn, v cc vi p

H thng cha chy c nh gm:

01 bn nc cu ha dung tch

2750 m3 bn trong Nh my, 01 b

nc dung tch 300 m3 bn ngoi Nh my.

Hnh: Bn nc cu ha

H thng bm nc cu ha: 03 my

52

bm. Phn phi nc cho cc tr nc

cha chy (Hydrant), cc sng phun monitor,

h thng phun sng (Water Spray)

02 bm chnh P-71 A/B: Cng sut 340 m3/h/my.

01 Bm b p P-73: Cng sut 30 m3/h.

Hnh: H thng bm cu ha

Tr nc cha chy (Hydrant): 22

tr c b tr xung quanh nh my,

cch nhau khong 50m 80m. Mi

tr nc cha chy c hp 1 lng A

v 2 cun vi

Hnh: Tr nc cha chy

Sng phun monitor: 05 ci b tr ti

khu vc cng ngh v trm nn u vo.

Cc hp ng lng, vi cha chy:

24 hp (48 cun vi, 24 lng) c

b tr theo tng khu vc thit b trong nh my

Hnh: Sng phun monitor

H thng phun sng (Water Spray):

c kch hot thng qua h thng van

x nc t ng Deluge Valve (10 ci).

Hnh: H thng phun sng

53

H thng phun bt cha chy ti bn

Condensate: bn cha foam dung

tch 1516 lt, 02 lng phun. Thi gian

phun x bt l 55 pht vi mt 4,1l/m2/p.

p sut trong ng ng lun c duy

tr t 10 12 Barg

Hnh: H thng phun bt cha chy

ti bn condensate

H thng cha chy t ng bng kh

CO2 loi 45 kg: 79 bnh ti khu vc

Nh my pht, Trm Dinh C, Scada.

Hnh: H thng cha chy t ng

bng kh CO2

H thng cha chy t ng bng

bnh bt dng treo (26 bnh loi 8kg)

ti kho ha cht v kho du m.

Hnh: H thng cha chy t ng

bng bnh bt dng treo

54

Hin GPP ang ci to, xy dng h thng cha chy bng nc thay cho h thng

cha chy bng CO2 ti khu vc trm Dinh C c.

H thng cha chy di ng gm:

Nh my c trang b 01 xe cha

chy cng y cc trang b v

phng tin: Lng, vi, foam,

km theo trc PCCC 24/24;

Hnh: Xe cha chy

Cc bnh cha chy bng bt

loi xe y:32 bnh (loi:158kg,

50kg, 45kg, 35kg, 22.7kg)

Hnh: Bnh cha chy bng bt loi xe y

Cc bnh cha chy bng bt loi xch

tay: 82 bnh (loi: 9kg, 8kg, 6kg). Cc

bnh cha chy CO2 xch tay: 34 bnh

(loi:9kg, 7kg, 5kg, 3kg).

Hnh: Bnh chy bng bt loi xch tay

55

02 xe Foam di ng dung tch

100 lt/xe; 01 my bm TUHATZU V75

cng sut 123m3/h

Hinh: Xe Foam di ng

2.3.14 Kh r r

Tt c cc im r r cht c hoc kh chy u phi c treo bin cnh bo,

hng ngy o gim st nng r r v c bin php khc phc.

Nhng im r r khi o c nng kh chy >60%LEL phi khc phc ngay

cng sm cng tt. Trong thi gian ny nhn vin vn hnh phi tng cng kim sot,

hn ch ngi qua li. Di di cch ly trit ngun nhit/in gn k v sn sng ng

cu nu c chy n xy ra.

2.3.15 ng cu khn cp

Mi ngi lm vic trong khu vc sn xut ca cng ty nh vn hnh, phng

chy cha chy, bo v u c trch nhim sn sng ng cu nu tnh hung khn

cp xy ra.

Khi pht hin cc yu t nguy him c th gy s c phi lp tc bo cho

ngi chu trch nhim khu vc tm bin php x tr.

Tun th nhng mnh lnh ca cp trn, thao tc ng qui trnh ng cu

c hun luyn nh thng tin phi hp, c lp, gim p, x kh, ngt dng, vn hnh

thit b cha chy .

Tham gia gii quyt cc hu qu ca s c.

2.3.16 Giao ca

Giao ca ng v tr quy nh.

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Phi bn giao cng vic cho ca sau mt cch y , c bit cc cng vic

cn ang dang d cn theo di gim st cht ch.

Khi giao ca phi bn giao cng vic v c ti sn v k nhn vo s giao ca.

2.4 An ton phng chng chy n do tnh in trong tn tr xut nhp xng du

2.4.1 Nguy c tnh in v cc cht ph gia tnh in

2.4.1.1 Gii thiu chung

Nguy c tnh in trong ngnh xng du l mt ch c xem xt nhiu ln

nhng vn cn tip tc xem xt na. Vic x l cc hydrocacbon d chy vi cc tnh

hung tch n qu mc c t ra cng lun tm n cc ri ro. K t nm 1960 n

1961, vin du m M API lit k c 121 v chy n trong qu trnh tra, np

xng du cho sitec. Khong 70% trong s xy ra trong qu trnh sang np t sn

phm c p sut hi cao sang sn phm c p sut hi thp, v d np sitec ang ch

xng sang diezen hoc du ha, nhin liu bay. Gn mt na xy ra khu lc tinh

ang thc hin trn tuyn ng. C v s cc tai nn xy ra khi i lung cho my lc.

Mc d cng tc thng k trn gip ch rt nhiu cho cnh bo ci thin tnh

hnh chy n nhng ti nn ni chung vn xy ra.

Tuy khng phi l tt c, nhng a s cc v tai nn tnh in l c th ngn

chn, phng chng c. Hu nh tt c cc s c v tnh in u xy ra cng mt

kiu v mc d c kinh nghim dy dn nhng cng khng th m bo rng thao

tc s c thc hin tuyt i an ton.

Ni dung chnh ca phn ny s ni v s tnh in c p dng cho nhin

liu hydrocacbon, dung mi v mt s bin php i ph thng c p dng nh s

dng mt s ph da ci thin tnh dn in

2.4.1.2 S tch in

S tch in xy ra khi cc b mt khc nhau c xc vo nhau: dng nhin liu

chy qua ng ng hoc khi trn cht rn vo trong cht lng, khi dng khng kh

i qua cnh qut hoc s lng ca nc qua cc hydrocacbon tuy nhin nhng hin

tng ny th t hn v khng r rng.

Mc to nn s tnh in ph thuc vo bn cht hai b mt. in tch

c tch khi t mt b mt v c mang n b mt kia. Trong trng hp nhin

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liu ca cc hydrocacbon sch rt t xy ra tch in v chng khng b oxi ha mt

cch d dng. Cc tp cht dng vt nh axit, cn, amin, mecaptan trng thi thin

nhin hoc c thm vo d dng b ion ha, to ra cc phn tch in. Tuy nhin,

trong thc t, d mun d khng, chng lun c mt v v vy, xu hng tch in ca

nhin liu l khng th d on c, chng c th dao ng ti thiu l 100 cp.

Quy m ca in tch pht sinh cng ph thuc vo tc ca dng chy.

c nh gi s b cho bit: khi tc ca dng chy tng ln hai ln th in tch pht

sinh trong ng ng s tng ln 4 ln. Tc dng chy nh hng do cc b phn

lc t c xc nh hn. Cc b lc tinh nh b lc ngng t c th to ra in tch

rt ln do c din tch b mt rt ln so vi ng ng hoc cc ng ni.

Vic tch in c th kim sot c mt cch tng i v hp l, nhng

khng th khng nh l kim sot c mt cch hon ton. Trong thc t c nhiu

ha hon xy ra trong cc h thng m trc khng c vn g. Ngoi ra cng c

mt s nh hng khng r lm nhng cng c th lm nhin liu nng ln khc

thng, lm in tch tng ln n hai ln so vi thng thng v tt yu s dn n s

c.

2.4.1.3 S tch t in tch

gii quyt c kt qu cc nguy c v tnh in c th xy ra vi xng du

v dung mi: vic tin hnh tip v ni t tt cng cha . Vic tip v ni t s

ngn chn c s tch t in tch trong cc vt cha ang c sang np xng du

nh sitec t v s ngn chn c tia la in phng t vt cha xung t, trong khi

kh nng bt chy ca hi nhin liu thot ra l ng k. Nhng ni v tip t s

khng ngn chn c su tch t in tch trong lng nhin liu vn c dn in

thp. dn in thp s lm mc in tch duy chuyn rt chm qua chnh bn thn

nhin liu v phi mt n vi pht in tch dch chuyn qua nhin liu n c

v vt cha xung t. Mt vi pht c th l qu lu i vi mt vt cha nh sitec

ot ang sang np nhanh vi nhin liu b tch in cao nhng li truyn dn in chm

v trong khong thi gian trc khi in tch c dn qua nhin liu ti t th mt

in th b mt cao c th tn ti ti hng kV. S phng tia la in v c th gy

chy. Hn hp khng kh + nhin liu tng i d b t chy khi ch cn mt nhit

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lng 0.2 milijun tp trung u tia la in.

y l mc cn ghi nh cho mi ngi khi lm vic trong mi trng xng

du cho cc lai hydrocacbon d chy.

Tuy nhin, vic phng in c th xy ra theo nhiu cch. S phng in nguy

him nht l t mt vt th tch in v c kh nng dn in nh kim lai ti mt vt

c kh nng dn in khc. V d: s phng in t mt chic can kim lai tch in

(ni trong nhin liu) ti thnh trong ca bn cha, hoc ti ng x (drop tube) ang b

cch ly (cha ni t). S phng in khi ang th thc o ni theo ng i ca n

trong bn ang nhp hng, iu lm cho n tc thi b cch ly.

Cc trng hp xy ra s rt nguy him l v vt dn tch in c th mang

ht in tch ca n vo thi im pht tia la in ngay lp tc, to v phng in

nhanh vi cng ln. V vy, cc vt kim lai ang b cch ly cn phi thn trong

lai b, khng cho chng tip xc vi nhin liu ang b tch in.

in th b mt vt qa 1kV c th dn n vic pht tia la in v gy

chy. in th b mt d dng pht sinh trong cc thao tc thng thng.

S phng in kiu chm c th xy ra t b mt nhin liu ti thnh trong

ca b cha nu in th b mt vt qu 30 KV v c th to ra nhit lng gy

chy trong hn hp khng kh + nhin liu. Kiu phng in ny c th xy ra vi

mt vt tch in, nhng khng th t ti in th cao v b mt khng c tinh dn

in nn in tch khng th d dng gii phng trong cng mt ln phng in duy

nht. in th b mt cn thit gy chy c th d dng t c khi xng du ang

bm vi mt lu tc rt ln hoc c th xy ra khu lc tinh gn ni tra np xng du

vo phng tin. S phng in kiu qung cng c th xy ra t b mt tch in cc.

Lai phng in ny him khi c nng lng cn thit gy chy.

2.4.1.4 Hin tng mi chy

Nu thng xuyn c s tch in, in tch s t li v c s phng in vi

nng lng ln gy chy th iu kin cui cng ch yu xy ra s chy l mi

trng chy. Yu t hng u trong vic xy ra chy xe sitec l vic tin hnh cp

hng vo cc sitec c s chuyn i hng ha loi vt chuyn m in hnh l t xng

sang diezen.

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Bn thn vic tra np xng khng c nguy c v tnh in v khng gian th hi, t

bit ch pha trn b mt cht lng l c giu hi nhin liu sn sng pht chy. Phn

xng ng li, t bit nhit thp, khi xy ra ngng t th cng d dng bt chy.

Cc sn phm c p sut hi trung bnh nh nhin liu phn lc JP 4 , toluene, v cc

dung mi khc c th to ra mi trng d chy v s bt chy c th d dng xy ra t

tia la in nu c nng lng gy chy. Ha hon cng tng xy ra vi cc sn

phm c p sut hi thp nh KO, DO khi bc hi v ta ra di dng m sng.

mi t cc m sng ca cc cht cn phi c tia la in c nng lng cao hn.

Vic mi chy cc m song c th d dng trnh c nu c thit b v phng php

thc hnh thch hp. Phng php cp xng du t y vt cha ln c th gim c

nguy c chy do m sng, nhng vic np t y cng khng th gim c ng k

kh nng bt chy ca hi nhin liu.

Cc hydrocacbon khng tch in i vo sitec cha v b tch in mt t khi i

qua cc ng ng, v c th b tch in cao khi i qua my bm v cc my mc

khc c bit qua b lc. Khi s tch in mc cao m dn in li thp, in

tch s tch t li cng vi nhin liu trong xe bn v do ton b h thng c ni

t nn s phng in gy chy c th khng xy ra, nhng nu mi trng to mt

hn hp c th chy th s bt chy vn c th xy ra.

2.4.2 Lm th no gim ti a vic pht sinh in tch

Ni chung, hin nay vn cn qu t cc n lc khng ch xu hng tch

in ca nhin liu, ngha l khng ch cc tp cht dng vt dn n s tch in khc

thng. Nguyn nhn l do c nhiu loi tp cht v cc lai ph gia c trong nhin

liu iu c xu hng in tch ring trn cc b mt khc nhau. V vy ngi ta buc

phi tha nhn mt khong rng gi tr in tch c th pht ng trong h thng x l

nhin liu. Tr khi ph gia dn in c p dng, lu tc chy qua h thng ng cn

phi hn ch n 7m/s. iu cn c tnh ton da trn ng ng c bn knh nh

nht trong h thng v trong khong thi gian 100s chy ti u vo ca thng cha.

Ti a s cc nh my lc du, my bm thng c t kh xa hng xut

ca xe bn hoc cc phng tin cha khc. Tuy nhin, cc thit b lc tinh li c xu

hng lp gn ni hng xut nhm m bo yu cu lc sch cho nhin liu. y l

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mt vn cn xem xt tnh ton cho ph hp. Khong cch lp t b phn lc (c

li lc tinh, cp micro) ti xe bn phi tha mn yu cu: khng c gn hi khong

cch m sau thi gian 100s, dng chy t u ra ca n ti c xe bn, tr khi trong

nhin liu c s dng ph gia dn in. L do: in tch kp chuyn t ng

ng xung t. (Ha hon tng xy ra trong trng hp khong cch c t di

30s). Ging nh my lc cc cht huyn ph rn v cht lng c th to ra mt in

tich b mt rt ln dn ti hin tng tch in nhiu ln, thm ch t qu trnh lng,

c bit l khi b khoy.

2.4.3 Lm gim qu trnh tch t in tch

Ni v tip t cc vt kim loi nhin liu tch in l mt iu c bn ca an

ton tch in v c thc hin tt c cc hng.Song cng tc an ton v cc tc

nghip an ton vn rt cn c lin tc tng cng. Mt s ha hon xy ra t

hng bm ti thng cha do khng ni t v s lng ha hon ny c th cn ln

hn do vi cc v do xe sitec gy ra.

dn in ca nhin liu s khng cn ngha g mt khi nhin liu tch

in khi i qua vi bm v ri t do xung thng ng khng c ni t. V vy cc

thng cha bng kim loi, hoc c rut bng kim loi t trong cc thng nha, cn

phi c ni t khi hng t vi bm xng du.

Vic c thi gian cho cc in tch kp truyn xung t l rt cn thit. Do

lng in tch to ra khi chy qua ng ng nh hn nhiu so vi in tch to ra t

khu lc, Vic ngng khong 100s trong ng ng sau khi lc cho php in tch

sau khi lc c tn i. in tch to ra khi nhin liu chy qua ng ng thp hn

nhiu ln nn ni chung c th chp nhn c khi lu tc hn ch n 7m/s. Thi gian

lu c th to c nh mt thng cha c dung tch bo m lu c 30s hoc lu

hn trong thng. Tm li, nh tng tc dn in ca nhin liu, ti mc m in

tch ca nhin liu dn ti t c gia tng th mc nguy him s khng cn.

2.4.4 Gim s phng in tch

S phng in kiu chm t b mt nhin liu tch in khng th d dng loi

b, nhng n ch xy ra khi in th b mt t c ng k khong 30kV hoc ln

hn. Mt khc vic phng tia la in t vt kim loi b cch ly c tch in c th xy

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ra in tch nh hn nhiu, ch cn 1kV. Bng vic bo m cho tt c cc thit b

bng kim loi c ni t, v khng cho cc vt kim loi tri ni trong thng cha

th c th trnh c dng phng in nguy him nht t vt tch in kim loi ti b

mt kim loi. V l do , khi ang bm hng, cc dng c ly mu khng c th

xung thng cha sitec... v sau khi bm cng cn ch mt thi gian. V nu nhin

liu vn cn in tch xt li tuy khng nguy him ( chng hn 1kV, qa thp cho kiu

ng chm) nhng vic ly mu bng cc dng c kim loi nn vn c th phng in

vo v bn, b khi n c ko qua ming l o.

2.4.5 Loi b mi chy

Nu hn hp c th to ra hn hp mi chy l nhin liu v khng kh khng

c mt ng nhin s mi chy khng th xy ra. Nh vy c th bo m chc chn

rng vic loi b hin tng mi chy c th bng cch: loi b nhin liu hoc khng

kh. Mt s hng xng du ln ra mt s chnh sch nghim ngt l phi hn ch

vic chuyn i loi hng ha trong qa trnh vn chuyn v tn cha i vi xe sitec

v i vi cc b cha. Nu thc hin c nghim ngt cng vic th nhng tai ha

gy chy do giao nhn, vn ti, bm rt i vi cc sn phm c p sut hi thp nh

KO, DO c th c li b kh nhiu. Mt s bin php c hiu qu khc, c thc

thi trong qu kh, l dng kh nit, CO2, hoc khi