Wastewater Treatment - Tertiary and Sludge Handling Prepared by Furby Ramos

7/25/2019 Wastewater Treatment - Tertiary and Sludge Handling Prepared by Furby Ramos

1/23

Wastewater Treatment

Sludge/Biosolids Handling

Prepared by:

Franz Furby C. Ramos


2/23

What remains to be disposed of is a mitureof solids and !astes during the !aste!atertreatment is "alled pro"ess residuals ormore "ommonly referred to as sludge orbiosolids.

Sludge is "ommonly a""epted name for

!aste!ater solids# ho!e$er if the!aste!ater sludge is used for bene%"ialreuse it is referred to as biosolids.


3/23

Sludge treatment methods are generallydi$ided into three ma&or "ategories:

'hi"(ening

Stabilization

)e!atering


4/23

Sour"es of Sludge

Waste!ater sludge is generated in primary*se"ondary* and "hemi"al treatment pro"esses.

+n primary treatment the solid that ,oat or settleare remo$ed (no!n as s"um. 'he settleablematerial that "olle"ts on the bottom of the

"lari%er "an also be referred to as primary sludgeor ra! sludge


5/23

Solids not remo$ed in primary "lari%er arereferred to as "olloidal suspended solids. 'hese"ondary treatment is designed to "hange those"olloidal solids into settleable solids that "an be

remo$ed.

-n"e in the settleable form in the se"ondary"lari%er the sludge "olle"ted at the bottom of the

se"ondary "lari%er is "alled se"ondary sludge.


6/23

Sludge Chara"teristi"s

Sludge "ontains about 0 1 !atter.

Sludge handling may represent up to 234


7/23

+n the pro"ess of purifying !aste!ater*another problem is "reated: sludge. 'hehigher the degree of !aste!ater treatment*the larger the residue of sludge that mustbe handled.


8/23


9/23

'he basi" pro"esses for sludge treatment

are:

1. Preliminary operations:

S"reening* grinding* degritting* blending* andstorage may be part of the preliminary operationsto prote"t do!nstream e5uipment and/or pro$ide

a homogeneous feed to subse5uent pro"essfa"ilities.


10/23

2. Thickening:

'hese pro"esses are used to separate !ater fromthe solids to redu"e the size of subse5uent

fa"ilities and to impro$e their e"ien"y. 'he !ateris separated by gra$ity* ,otation* gra$ity belt*rotary drum %ltration* or "entrifugation.


11/23

Sludge thi"(ening

+t is a unit pro"ess used to in"rease solid "ontentof the sludge by remo$ing a portion of the li5uid

fra"tion.

'his pro"ess in"ludes: ;ra$ity thi"(eners

Flotation thi"(eners

Solids "on"entrators:


12/23

;ra$ity thi"(ening is most e


13/23


14/23


15/23

7. Stabilization:

Sludge is stabilized to redu"e pathogens* eliminateo


16/23


17/23

AEROBI !I"E#TIO$ PROE##

O$TRO% A%&%ATIO$#


18/23

'. on(itioning:

'hese pro"esses treat the sludge !ith

"hemi"als or heat so that more !ater "anbe readily separated.


19/23

). !ewatering:

'hese pro"esses are used to further redu"ethe !ater to meet disposal regulations*impro$e handling* redu"e transportation "osts*pre$ent lea"hate from disposal sites and* inthe "ase of follo!?on redu"tion pro"esses =i.e.*in"ineration>* redu"e the energy re5uirements.

'he separation pro"esses in"lude"entrifugation* %lter presses* and drying beds.


20/23


21/23


22/23

Belt %lter press


23/23

Treate( #l*(ge +,iosoli(s-

Documents

Wastewater Treatment - Tertiary and Sludge Handling Prepared by Furby Ramos