Calculo diseno MBR

ALHADBA ALKAHADRA Process Design

DESIGN PARAMETERS

DESIGN BASIS (INPUT)

Population equivalent [P.E] [N° ~] 440.000

Hydraulic Load

Daily flowrate QDW,d [m3/d] 110.000Peak flowrate QPK,d [m3/d] 165.000 [ QDW,d * 1,5]

Q average flow QAVE [m3/h] 4583 [m3/s] 1,27Q dry peak flow QPKF [m3/h] 6875 [m3/s] 1,91

Loads of pollution

CODL,C [Kg/d] 165000 [mg/l] 1500BOD5 L,C [Kg/d] 38500 [mg/l] 350TDSL,C [Kg/d] 110000 [mg/l] 1000TSSL,C [Kg/d] 38500 [mg/l] 350TNL,C [Kg/d] 6600 [mg/l] 60NH3 L,C [Kg/d] 4950 [mg/l] 45TPL,C [Kg/d] 1100 [mg/l] 10FOGL,C [Kg/d] 5500 [mg/l] 50pH 6,5÷7,5

Return liquor

Increase hydraulic & pollution loads for residual water and supernatants from sludge line.

Daily flowrate QDW,D [m3/d] 4.246 (range 3 ÷5% QDW,d)

CODL,C [Kg/d] 9.900 [mg/l] 2332BOD5 L,C [Kg/d] 2.310 [mg/l] 544TSSL,C [Kg/d] 2.695 [mg/l] 635TNL,C [Kg/d] 198 [mg/l] 47TPL,C [Kg/d] 33 [mg/l] 8

TOTAL hydraulic & pollution loads inlet plant

QDW,d [m3/d] 114245QPK,d [m3/d] 169245QAVE [m3/h] 4796 [m3/s] 1,33QPKF [m3/h] 7087 [m3/s] 1,97

CODL,C [Kg/d] 174900 [mg/l] 1531BOD5 L-C [Kg/d] 40810 [mg/l] 357,2TSSL-C [Kg/d] 41195 [mg/l] 360,6TNL-C [Kg/d] 6798 [mg/l] 59,5TPL-C [Kg/d] 1133 [mg/l] 9,9FOGL-C [Kg/d] 5500 [mg/l] 48,1pH 6,5÷7,5

Wastewater temperature ( for process)

Average wastewater temperature for different periods of the years

- Average winter [T °C] 15 [period three months]- Average. orther seasons [T °C] 20 [period six months]- Average summer [T °C] 25 [period three months]

Effluent quality Standards

COD [mg/l ≤] 50BOD5 [mg/l ≤] 10TN [mg/l ≤] 20NH3 [mg/l ≤] 1TP [mg/l ≤] 10TSS [mg/l ≤] 10TDS [mg/l ≤] 1000FOG [mg/l ≤] 5

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MAIN INLET CHANNEL & MANUAL SCREEN

Data inputQMAX [m3/h] 7087QMIN [m3/h] 4796VMIN [m/s] ³ 0,5 (Self cleaning velocity)

Calculation channelFlowrate QMAX 1,97 [m3/s]

QMIN 1,33 [m3/s]Width channel Wch 2,5 [m]Height channel Hch 1,5 [m]Rougness Ks 65 [m1/3/s] (Gaukler-Stricker's formula)Slope i 0,5 [‰]Hydraulic Parameters W.L.max 0,85 [m]

Vmax 0,92 [m/s]W.L.min 0,65 [m]Vmin 0,82 [m/s]

Flow table Depth Wet Hydraulic Velocity Flow FlowWater Area RadiusW.L A R V Q Q[m] [m2] [m] [m/s] [m3/s] [m3/h]

0,65 1,62 0,43 0,82 1,33 47990,85 2,13 0,51 0,92 1,97 7089

Calculation screen

Channel Width [Wch] mm 2500Channel Depth [Hch] mm 1500

Type screens CoarseModel ManualN° screens N° 1Flow (Qmax) m3/h 7087 (Qmin) m3/h 4796H1 [W.L. upstream- max] mm ~ 1,05H1 [W.L. upstream- min] mm ~ 0,75Ws ( actual screen) mm ~ 2400St (bar thickeness) mm 10Spw (bars mesh) mm 50a (Inclination screen) ° 65Su (Surface actual screen) m² 2,788

m² 1,980Free cross section m² 2,323

m² 1,650I (factor clogging) 0,8Vc upstream m/s 0,92VsMAX (through screen) m/s 1,06VsMIN (through screen) m/s 1,01Head losses [Imposed max] m 0,2Head losses [Imposed min] m 0,1

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MECHANICAL SCREENS

Data inputQDW,d [m³/d] 114.245QAVE [m³/h] 4.796 [m³/s] 1,33QPKF [m³/h] 7.087 [m³/s] 1,97

Configuration

Main screen line [N°] 3Width channel Wch 1,5

Height channel Hch 1,5By-pass screen line [N°] 1

Width channel Wch 2,5Height channel Hch 1,5

Flowrate per channelMain line QMAX [m³/h] 3544 (Required 50% of the peak influent flow)

QMIN [m³/h] 1599

By-pass line QMAX [m³/h] 7087QMIN [m³/h] 4796

Design screening channels

Main lines By-pass lineScreening channels [N°] 3 [N°] 1Wch [m] 1,5 [m] 2,5 i 0,0005 0,0005W.L. min /max [m] 0,47 0,84 [m] 0,65 0,85A [m²] 0,7005 1,256 [m²] 1,6175 2,130Pb [m] 2,434 3,175 [m] 3,794 4,20Ri [m] 0,288 0,396 [m] 0,426 0,507Q min/max [m³/h] 1599 3545 [m³/h] 4797 7087V min/max [m³/s] 0,63 0,78 [m³/s] 0,82 0,92

Calculation & screens selection

Velocity between screensVs [m/s] min. ≥ 0,5 on QAVE

max ≤ 1,2 on QMAX

Screen Type Fine ManualSpacing (Spw) mm 6 25Constriction % 75 71Required unit cross section m² ≥ 1,09 2,30

Screen Width (Ws)

Dimensions & operating features

Main lines By-passChannel Width [Wch] mm 1500 2500Channel Depth [Hch] mm 1500 1500

Type screens Fine CoarseModel Step or belt Manual N° screens N° 3 1Flow (Qmax) m3/h 3544 7087 (Qmin) m3/h 1599 4796H1 [W.L. upstream- max] mm ~ 1,19 1,10H1 [W.L. upstream- min] mm ~ 0,62 0,75Ws ( actual screen) mm ~ 1400 2400St (bar thickeness) mm 2 10Spw (bars mesh) mm 6 25��(Inclination screen) ° 65 65Su (Surface actual screen) m² 1,835 2,919

m² 0,953 1,979

Q = Vs × Ws × H1×[Spw/(Spw+St)] × I QWs = --------------------------------------------- H1× Vs × [Spw/(Spw+St)] × IWs = Wch - 100�H = K1 × [St/Spw]4/3 × V2/2g x sen �

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Free cross section m² 1,376 2,085m² 0,715 1,413

I (factor clogging) 0,65 0,85Vc upstream m/s 0,78 0,92VsMAX (through screen) m/s 1,10 1,11VsMIN (through screen) m/s 0,96 1,11Head losses [Imposed max] m 0,35 0,25Head losses [Imposed min] m 0,15 0,1

Mechanical equipment :- Fine screens 6 mm N° 3- By-pass screen 25 mm N° 1- Screening conveyors N° 1- Screening wash compactor N° 2 (Type screw press compactor)- Penstocks N° 8

Total screening material

Fresh screening material- Total specific production lt/m³ 0,15- Density Kg/l 0,65 [range 0,6÷0,7]- Humidity % ~ 75- Quantity average lt/d 17137 14,22 l/PE/year [range 5 ÷ 20 ]

kg/d 11139Compacted screening material- Weight reduction % ~ 65- Volume reduction % ~ 65- Quantity compacted kg/d 3899

lt/d 5998 4,98 l/PE/year

Screening containers- Storage capacity days 5- Volume storage m³ 30- Containers N° 4 ( + 2 as spares)- Capacity [Required] m³ 9,4 ( "Easily lifted type" ) [Chosen] m³ 12

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AERATED GRIT & GREASE REMOVAL

Data inputQDW,d [m³/d] 114245QAVE [m³/h] 4796 [m3/s] 1,33QPKF [m³/h] 7087 [m3/s] 1,97

Design

Type Combined longitudinal spiral actionSystem PreareationSurface load max m³/h*m² 20 ÷ 25Cross sectional speed max cm/s < 8 (long grit chamber)HRT (hours) ≥ on Qave 0,3HRT (hours) ≥ on Qmax* 0,17 (* Required 75% of the peak flow / unit)Air specific m³/m³*h 1÷1,5

Volume Vu (calculated) m³ 1580Cross section St (calculated) m² 24,6Vu (Selected) m³ 1790

Characteristics and operating features

Units N° 3Volume unit m³ 597Cross section unit m² 19Hydraulic depth m 4Length unit m 31Width unit m 7Width grit zone m 4,5Width grease zone m 2,5

Operating featuresHRT Surface L.Cross Speed

[minutes][m³/m²*h] [cm/s]QAVE 22,40 11,31 3,51QPKF 15,15 16,72 5,18QMAX (*) 10,10 25,08 7,77

(*) 75% of the peak design flow

Process air supply

- Air distribution system Type coarse tubolar bubble diffuser

Check (by Kalbskopf)- Air specific [range] ft³/min*ftL 2 ÷ 5 (Metcalf&Eddy - Wastewater Engineering )- Air specific [Assumed] ft³/min*ftL 3 [ Equivalent] m3/h*m. L 16,7- Total air required m³/h 1575

Check ( by ATV Standard)- Air specific (range) m3/h*m3 v 0,5÷1,5- Air specific [Assumed] m3/h*m3 v 1,0- Total air required m³/h 1790

Q air [Chosen] m³/h 1700

Performance (Removal)- Sand/grit ØP > 0.20 mm % > 95 ( particles having specific gravity > 2,0 )- Oil & grease flottable % > 95

Sand & grit removal

Removal system Type by air-lift pumpsFresh material- Production [Range] ft³/Mgal 0,5÷27 (Metcalf&Eddy - Wastewater Engineering ) [Assumed] ft³/Mgal 10

m³/103m3 0,075

- Volume grit m³/day 8,228l/PE/year 6,8 (Range 2 ÷ 15)

- Quantity grit T/d 14,0

Treatment sand- Type Sand wash classifier- Organic content < % 3

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- Sand humidity % 10÷15

Sand & grit containers- Storage capacity days 3- Volume storage m³ 25- Containers N° 3- Capacity [Required] m³ 10,3 [Chosen] m³ 12 ( "Easily lifted type" )

Oil & grease removal

Removal system Type by surface scraper- Production l/103 m3 49

l/PE/year 3,7l/d ~ 5552

- Density Kg/l 0,8- Daily quantity Kg/d 4441

Oil & Grease containers- Storage capacity days 2- Volume storage m³ 11- Containers N° 2- Capacity [Required] m³ 6,9 [Chosen] m³ 8 ( "Easily lifted type" )

Equipment

- Sand removal system N° 3 Type " Botton screw conveyor "- grease removal system N° 3 type " Rotating surface scraper "- Main Air compressors N° 3 + 2 R Rotary type Q = 600 m³/h , H = 4,5 m.- Aeration system Type medium bubbles tubolar diffusers- Blower per air-lift N° 1 + 1 R Rotary type Q = 120 m³/h, H = 7-9 m.- Air lift pumps N° 3 DN 100- Sand wash classifiers N° 2 (Type screw Qhydr. = 50 ÷ 60 m³/h)- Containers sand N° 3 ( capacity 12 m3)- Containers oil/grease N° 2 ( Capacity 8 m3)

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CHARACTERISTICS EFFLUENT FROM PRETREATMENT

Pollution Removal (Performance)

[Expected Value]COD �� [% ~] 10BOD5 �� [% ~] 5TSS � [% ~] 5�� [% ~] 0TP � [% ~] 0

Characteristics effluent

[Kg/d ] [mg/l]CODOUT 157410 1378BOD5OUT 38770 339TSSOUT 39135 343TNOUT 6798 60NH3-OUT 4950 43TPOUT 1133 10

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BIOLOGICAL TREATMENT

The biological treatment process is realized to :- Ensure the proces of nitrification- Ensure a high removal of the BOD and COD loads- Guarantee a high sludge age- Optimed the partial phosphorous removal- Optimize the supply of air to the process by the prevision of diffused air oxygenation system

Data input

QDW,d [m³/d] 114245QAVE [m³/h] 4796 [m3/s] 1,33QPKF [m³/h] 7087 [m3/s] 1,97

CODINL [kg/d] 157410 [mg/l] 1378BOD5INL [kg/d] 38770 [mg/l] 339TSSINL [kg/d] 39135 [mg/l] 343TNINL [kg/d] 6798 [mg/l] 60NH3-INL [kg/d] 4950 [mg/l] 43TPINL [kg/d] 1133 [mg/l] 9,9

Wastewater temperature for design biological process

Average winter °C 15 [period three months]Average other seasons °C 20 [period six months]Average summer °C 25 [period three months]

Effluent quality after biological treatment

CODOUT [mg/l ≤] 120BOD5OUT [mg/l ≤] 30TSSOUT [mg/l ≤] 35TNOUT [mg/l ≤] 20NH3-OUT [mg/l ≤] 1TPOUT [mg/l ≤] 10

Design biological treatment

A ) Design process in relation to biological efficiencies (� BOD5) and sludge load F/M (kg BOD/kgMLSSx d )

BOD5 organic performance [ �� = (BODin - BODout) / BODin ]

BOD5 inl mg/l 339BOD5 out (< 30) mg/l 28��BOD5 [required] % 92� BOD5 [chosen] ≥ % 92%

Reference Horler - Wuhrman Relation

� BOD5 = 1 / [1+ 0,2 x ( F/M ) 0,5]

Sludge load (F/M) necessary ≤ 0,19 KgBOD5/KgMLSS*d

Design parameters for process :

Type process Conventional medium load activated sludgeVolumetric Load ≤ 0,76 KgBOD5/m³*d MLSS concentration CMLSS 4 KgMLSS/m3

VOX (minimum required ) m³ 51273

B ) Design process in relation to nitrogen treatment

Process with biological phosphorous removal and nitrogen treatment.

- TN ( nitrogen balance)

T. wastewater °C 15 20 25TN inlet biological treatm. ppm 60 60 60TN out ppm ≤ 20 20 20

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N-bacterial synthesis ppm ~ 15,27 15,27 15,27N-NH4 out. ppm 1 1 1N-NO3 out. ppm 18 18 18N-org. out. ppm 1 1 1N to nitrificate ppm 43,23 43,23 43,23

Kg/d 4939 4939 4939� nitrification [required] % ≥ 72,7 72,7 72,7N to denitrificate ppm 25,23 25,23 25,23

Kg/d 2883 2883 2883��denitrification [required] % ≥ 58,4 58,4 58,4

-TP ( biological phosphorous removal)

TP in ppm 10Kg/d 1133

P - bacterial syntesis ppm 3,1TP residual ppm 6,80TP required at outlet ppm < 10TP to be removed ppm 0

Not necessary further chemical treatment for phoshorous removal

Design of de-nitrification system

De-nitrification velocity ( Vd ) T° = ( Vd ) 20° x K [T - 20]

Temp. Wastewater [T °C] 15 20 25( Vd ) 20° = gr N-NO3/Kg SSV* h 2 ÷ 3K 1,08K T - 20 0,68058 1,00 1,47Ratio SSV/SST 0,75(Vd)T° = gr N-NO3/Kg SST h 1,531 1,800 2,204

Volume of de-nitrification VDN

N to the de-nitrification Kg/d 2883 2883 2883SST required Kg 78438 66730 54498CMLSS [Supposed] KgSS/m3 3,8 3,5 3VDN [calculated] m³ 20642 19066 18166

VDN [Selected] m³ 21000

BOD5 removal in denitro Kg/Kg Nd 3,5KgBOD/d 10090 10090 10090mg/l 88,3 88,3 88,3

Design of nitrification system

Nitrification velocity

( Vn )T° = ( Vn )20° x K T - 20 x ( NH3 ) / ( KTKN+ NH3 ) x ( O.D.) / ( KD + O.D.)

Temp. Wastewater [T °C] 15 20 25(Vn)20° = g N / Kg SSVN * h 90÷110Ratio SSV/SST 0,75(Vn)20° = g N / Kg SSTN h 65 ÷ 80K factor 1,12K T - 20 0,57 1,00 1,76NH3 = N-NH4 out ppm ~ 1 1 1KTKN = 10 0,051 T -1,158 ppm 0,40 0,73 1,31KD ppm 1O.D. dissolved oxygen ppm 2,5 2,5 2,5(Vn)T°C = g N / Kg SSTN h 21,6 31,0 40,9R1 = ratio BOD in/ TKN in 5,7f 0,045(Vn)T°C = g N / Kg SST h [Selected] 1,01 1,22 1,45

Volume of oxidation-nitrification VN

N to nitrificate Kg/d 4939,13 4939,13 4939,13SST required Kg 204773 168686 141929CMLSS [Supposed] KgSS/m3 3,8 3,5 3VN [calculated] m³ 53888 48196 47310

VN [Selected] m³ 54000

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Total re-circulation Nitrates (N-NO3) into denitrification

The total flow of nitrates to recicle into denitrification section is calculatedwith following balance:

R = [ TNinl - TNout - (NO3)out - 0,05 x ( BODinl - BODout )]/ (NO3)out

QAVE x NO3d = (QR)d x (N-NO3)out

Ratio = (QR)d / QAVE ~ 1,40 1,40 1,40(QR)d calculated m³/h 6723 6723 6723(QR)d Selected m³/h 6750 6750 6750(QR)d yearly average m³/h 6750

and it include the Mixed-liquor flow (QMXL ) and Return active sludge( QRAS)

QRAS - Return activated sludgeQRAS m³/h 4350 3750 2900QRAS (yearly average) m³/h 3688

QMXL - Mixed liquor recirculation QMXL m³/h 2400 3000 3850QMXL (yearly average ) m³/h 3063

Mixed liquor recirculation pumps

Units n° 4 +2 Rtype submersible axial impellerCapacity each m3/h 963Head mwc 0,8Rated power kW 7,5Absorbed power P1 kW 6,0

Return active sludge ( RAS )

Average flow of RAS QRAS = QAVE x [ CMLSS / (CRAS-CMLSS) ]

CRAS average SS concentration in return sludge (KgSS/m³)CMLSS concentration MLSS in biological system (KgSS/m³)

Sludge index SVI mg/l 100÷ 125GS KgSS/m³ 11,45 [1000/SVI*(Tth^1/3)]CRAS KgSS/m³ 8CMLSS KgSS/m³ 3,8 3,5 3,0RAS = Co / ( Csr-Co) x 100 % 90 78 60QRAS [calculated] m³/h ~ 4339 3730 2877QRAS [assumed] m³/h ~ 4350 3750 2900QRAS yearly average m³/h ~ 3688

Max capacity PS (required) 150% of influent flowrateQRAS max capacity PS m³/h ~ 6875

RAS pumping stationPumps Type submersibleUnits N° 4 + 4 St-byCapacity unit m³/h 1720Head mwc 4 ÷ 5Rated power kW 45Absorbed power P1 kW 33,8

The capacity of the pumps for return sludge is variable between 50 - 150% of the average sludge flow.

(SAS) Surplus sludge production

�Fs = [1,0 -(K20*�T-20)/(� x Cf)] ( Bacterial syntesis growth & mineralization )

T.. Wastewater °C 15 20 25� BOD5 % > 92 F/M load KgBOD5/KgMLSS*d 0,136 0,148 0,172�Fs ( KgSS/Kg BODrem.) Bacterial. Syn. 0,78 0,71 0,63

inert material 0,30 0,30 0,30

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�Fs ( KgSS/Kg BODrem.) Calculated 1,08 1,00 0,93

Assumption�Fs ( KgSS/Kg BODrem.) Chosen 1,08 1,00 0,93Production Kg SS/d 38479 35738 33014Cr KgSS/m³ 8Q total surplus sludge m³/d 4810 4467 4127

For the process calculation it has been considered the weighted average of the different periods:

�Fs ( Kg SS/Kg BODabb.) Calculated 1,00Chosen 1,00

Production Kg TSS/d 35571Cr KgSS/m³ 8 [0,8%]Q total surplus sludge m³/d ~ 4450

SAS pumping stationPumps Type submersibleUnits N° 2 + 1 St-byCapacity unit m³/h 200Head mwc 8 ÷ 10Rated power kW 9Absorbed power P1 kW 7,25

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Selected dimensions of the biological treatment section

VDN m3 21000 28%VNT m3 54000 72%VAT biological treatment m3 75000

Denitrification tanksUnits provided N° 4Volume of unit m3 5250Hydraulic height m 6,5Length of unit m 40Width of unit m 20Mixing system into denitro tanks- Type mixer Submersible blade large propeler mixer- Average speed in the tank m/s ≥ 0,3÷0,4- Specific energy W/m³ 1,5- Total power necessary Kw 32- Mixer installed N° 8- Power output mixer Kw 3,94- Rated power mixer Kw 4,30

Nitrification-oxydation tanksUnits provided N° 4Volume of unit m3 13500Hydraulic height m 6,5Length of unit m 104Width of unit m 20

Operating features of the biological treatment section

In total denitro-nitrification (VN +VD )- Cv ( Volumetric Load ) KgBOD5/m3*d- Co (MLSS concentration) KgMLSS/m³ 3,8 3,5 3,0- Cm ( F/M load ) KgBOD5/KgMLSS*d 0,136 0,148 0,172- SRT (sludge age ) days 7,41 7,35 6,82- SRT (yearly average ) days

Retention timesQAVE h 15,64QPKF h 10,58

0,52

7,23

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Calculation of required oxygen for biological process

A] O2 at operative condition ( AOR - actual oxygen required )

AOR = FC× [ a × �BOD5 × BOD5] + [ b × ��T-20 × Co × Vox ] + FN × [ c × TKNnitrif.]

Symbols:a Active respiration factor [KgO2/KgBOD5 ]b Emdogenous respiration factor [KgO2/KgSS]c NH4 oxidation factor [KgO2/Kg TKN ]

BOD5 BOD5 inlet into oxidation [kg/d]TKN TN to be nitrified [kg/d]

� BOD5 performance removal [%]Co Concentration MLSS in oxidation [kg/m³]Vox Volume of ossidation-nitrification section [m³]T Wastewater temperature [ °C ]� Coefficient = 1,084

FC - FN Peak factor for BOD5 and TKN

Input: T. wastewater °C 15 20 25a KgO2/KgBOD 0,5��BOD5 % > 90BOD5INL Kg/d 28680 28680 28680

b KgO2/KgSS 0,12�T-20 0,668 1,000 1,497CMLSS Kg MLSS/m³ 3,8 3,5 3,0VN m³ 54000

c KgO2/KgTKN 4,6N to be nitrified Kg/d 4939 4939 4939FC ( BOD5 ) 1,5FN ( TKN ) 1,5

Yearly averageAORAVE [BOD5] KgO2/d 12.906 12.906 12.906 12.906 22%AORAVE [TSS] KgO2/d 16.452 22.680 29.097 22.727 39%AORAVE [N] KgO2/d 22.720 22.720 22.720 22.720 39%

52.077,7 58.306 64.723 58.353 100%

AOR MINIMUM KgO2/d 31246,6 34983,6 38833,6AOR AVERAGE KgO2/d 52077,7 58306,0 64722,6AOR PEAK KgO2/d 69890,7 76119,0 82535,6

B] Oxygen transfer at Standard Condition (SOTR)SOTR (water clean, T°C 20, P = 760 mm hg , O.D.= 0 mg/l )[e.g.: EPA Design Manual for Fine Pore Aeration Systems - EPA/625/1-89/023 ]

Aeration system Type Air with fine bubbles diffusion� 0,6� 0,98Top. °C 15 20 25Tst. °C 20Cs solubility O2 at Top. ppm 10,18 9,16 8,33Cst solubilityO2 at Tst. ppmA = altitudine m 50Hi = hydraulic detph m 6,2O.D. oxygen dissolved ppm 2,5

N/N� calculated 0,606 0,598 0,595

SOTRMINIMUM KgO2/d 51560 58523 65249KgO2/h 2148 2438 2719

SOTRAVERAGE KgO2/d 85933 97538 108749

9,16

(O2)op.(O2)st. = --------------------------------------------- N/N � (1013,3 - 0,10133 × A + 98,1 × Hi/2 ) [ �× Cs ×------------------------------------------------ ] - O.D. 1013,3 N/N� = � × ------------------------------------------------------------------ × Theta (Top-Tst )

Cst

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KgO2/h 3581 4064 4531SOTRPEAK KgO2/d 115326 127337 138679

KgO2/h 4805 5306 5778

SOTR [ DAILY AVERAGE ] KgO2/d 83671 94377 104675

C] Air distribution system

Diffusion type Fine bubble diffuser air (FBDA)Size m 60 ÷ 70 Submergence m.w.c. 6,2Q air minimum diffuser m³/h ≥ 1Q air max. diffuser m³/h 4�st. Max (SOTE%) % 40�st. Minimum (SOTE%) % 35

D] QAIR in standard condition SOTR

QAIR minimum m³/d 463669 526287 586775m³/h 19320 21929 24449

QAIR average m³/d 824300 935621 1043156m³/h 34346 38984 43465

QAIR peak m³/d 1185266 1308709 1425272m³/h 49386 54530 59386

QAIR (daily average) m³/d 809.329 912.524 1.011.763m³/h 33.722 38.022 42.157

E] Air diffusers

Diffusers Type Membrane disc with EPDM rubber or similar Diffusers [Range operative] m³/h >0,8 ÷ < 6Specific membrane surface m² > 0,038N° diffusors installed N° 15000Type diffusion TapperedDistribution of diffusers N°/m² 1,81Active surface diffusers m² 570Specific cover surface % ≥ 6,9%

F] Check diffusion system

Flow rate diffuser [m3/h] min 1,29 1,46 1,63ave 2,29 2,60 2,90peak 3,29 3,64 3,96

Specific Oxygen transfer - grO2/m³h /m. depth min 17,94 17,94 17,94

med 16,81 16,81 16,81peak 15,69 15,69 15,69

G] Air Normal Condition (Nm³ = 0°C, dry air, 1013 mbar)

Flow rate air minim. Nm³/h 18005 20436 22785Flow rate air average Nm³/h 32008 36331 40507Flow rate air peak Nm³/h 46025 50818 55345

Energy operational cost

Cold Period ( T waste ~ 15° C ) mounths 3Intermediate Period (T waste. ~ 20° C ) mounths 6Warm period ( T waste > 25 °C) mounths 3

Yearly average required O2 (SOTR) KgO2/d 94275KgO2/h 3928

Yearly average required AIR (SOTR) m³/d 911535m³/h 37981

Air production system

Standard air condition Normal Max

Temperature T1 °C 20 45°K 293 318

Intake pressure P1 mbar 1013 1013Relative Humidity UR % 60 60

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Density g1 kg/m³ 1,197 1,090

CompressorsType Centrifugal compressor (*)Compressors in duty N° 4Compressors in stand-by N° 1Capacity per units (requred) (at 20°C suction) m³/h 14946

(at 45°C suction) m³/h 16413Capacity per units (chosen) (max) m³/h 16500Head mwc 7,2Absorbed power unit (max) Kw 342Rated power unit Kw 400Total power installed Kw 2000

(*) Each compressor is design to supply air linear in the range from 40% to 100% of the max capacity

Aeration efficiency

Average efficiency blower kWa/m3/h 0,023Standard aeration efficiency (SAE) KgO2/Kwh 4,50

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SECONDARY SEDIMENTATION

Data inputQDW,d [m³/d] 114245QAVE [m³/h] 4796QPKF [m³/h] 7087QRAS min [m³/h] 2900QRAS max [m³/h] 4350CMLSS (concentr. Influent) [Kg/m³] 3,8 max

[Kg/m³] 3,0 min

Design parameters

Max overflow rate at Qmax m³/h*m² < 1,20Minimum retention time h > 2,0Specific weir loading m3/h*m 8 ÷ 10Max solid specific load KgSS/m²*h < 6Max sludge volume load (qSV) l/(m²*h) 500


Units n° 4Diameter unit Øi (assumed) m 44Hydraulic depth m 4Surface unit m² 1520Volume unit m³ 6079Total surface m² 6079Total volume m³ 24316Weirs for each tank n° 2Weir length each tank m 264Total weirs length m 1058

Retention times- QAVE [h] 5,07- QPKF [h] 3,43

Overflow rate- QAVE [m³/h*m²] 0,79- QPKF [m³/h*m²] 1,17

Weir hydraulic loads m³/h*m 6,70

Max Solid Specific load KgSS/m²*h 5,72

Surface sludge volume loading (qSV) [qSV = SVI* CMLSS*Overflow rate]- QMAX l/m²/h 487

Pag. 16 di 26



CHARACTERISTICS EFFLUENT FROM BIOLOGICAL TREATMENT

CODOUT [mg/l ≤] 120BOD5OUT [mg/l ≤] 30TSSOUT [mg/l ≤] 35TNOUT [mg/l ≤] 20NH3-OUT [mg/l ≤] 1TPOUT [mg/l ≤] 10

Pag. 17 di 26



SAND FILTRATION ( open gravity filters)

Data input

QDW,d [m³/d] 114245QAVE [m³/h] 4796QPKF [m³/h] 7087SST inl. (average) [mg/l ≤] 35SST out (average guaranty) [mg/l ≤] 10 (Value expected) [mg/l ≤] 6

Filtration pumping station

Pump type submersible pumpsNumber of pumps N° 3 + 1 stand-byFlow per pump m³/h 2398Head m 6÷8Absorbed power P1 kW 65,3Rated power kW 75

Design filtration

Filtration Type gravity filter bed with backwashing water & airFiltering materials Gravel + sand Hydraulic loads :-m3/h*m2 min > 5

max < 9 [ on QPKF ]max < 11 [ with one cell out ]

SF [calculated] m2 787SF [ chosen] m2 800

Technical characteristics

Units (filters ) N° 8Dimension each filter :- SF m2 100- L m 20- W m 5- HB bed depth m 1,5- VB bed filtering m³ 150Filtering materials - support gravel size 2 ÷ 4 mm

heigth 0,15 m - sand size 1,2 ÷ 2,0 mm

heigth 1,35 mUnderdrain system type nozzle

n°/m² 40

Operating features

Filtration rate ( normal service)- QAVE [m³/h*m²] 5,994- QPKF [m³/h*m²] 8,859

Filtration rate ( with cells in out)Cells in out [N°] 1- QAVE [m³/h*m²] 6,851- QPKF [m³/h*m²] 10,125

Backwash system

- Specific Water m³/hxm² 20- Water backwash (Calc) m³/h ~ 2000- Pumps N° 1+1 St-by- Pumps Type Submersible- Capacity m³/h 2000- Head m.w.c. 7÷9

- Specific Air m³/hxm² 50- Air backwash ( Calc) m³/h ~ 5000- Compressors N° 1+1 St-by- Compressors Type Rotary blower- Capacity m³/h 5000- Head m.w.c. 6÷8

Pag. 18 di 26



Bachwashing main data

- Solids capture KgSS/m³bed 4 (range 3 ÷ 7)- � solid capture % ≥ 85- Solid capture per filter KgSS 600- Solid inlet per filter KgSS/d 500- washing frequency filter N/d 0,83- Time backwash cycle with only air minutes 5 combined air/water minutes 10 with only water minutes 5- Washwater per cycle m³ 500- Daily washwater flow m³/d 3332- Washwater requirement % 2,92 of throughput (Range 3 ÷5%)

Return backwashing flow- SST out mg/l ≤ 8- DS production KgSS/m³ 0,027

KgSS/d 3085- Daily washwater flow m³/d 3332- DS concentration Kg/m³ 0,93

Pag. 19 di 26



DISINFECTION ( with gaseous chlorine )

Data input

QDW,d [m³/d] 114245QAVE [m³/h] 4796QPKF [m³/h] 7087

Design parameters

Retention times (minutes) on Qmax ≥ 10'on QAVE ≥ 30'

Reduction (3 log) % > 99,9Chlorine residual mg/l 2

Volume [calculated] m³ 2398


Contact tank Type plug-flowVolume [chosen ] m³ 2400Hydraulic depth m 3Units N° 1Volume each unit m³ 2400Surfice unit m² 800

Retention times- QAVE min. 30,0- QPKF min. 20,3

Disinfectant Type Gaseous chlorineDose [Cl active] MAX gr/m³ 5Dose [Cl active] on duty gr/m³ 3Daily consumption Kg/d 343Max dosage chlorination k/h 35Chlorinator Type Gas vacuum typeUnits N° 2 ( one stand-by)Capacity max Kg/h 40

Starage Chlorine days 30Storage capacity Kg 10282Chlorine drums necessary N° 12,85Chlorine drums installed N° 14Characteristics drums- Capacity liters 1000

Kg 800- Dimensions [mm] Ø x L 800 x 2000

Automation system by means flow measure and residual chlorine analyzer

Pag. 20 di 26



EFFLUENT PONDS

Data inputQDW,d [m³/d] 110000

Design parametersHRT days 1Volume (required) m³ 110000

Characteristics Volume (chosen) m³ 110000depth m 3,8Surface m² 28950

Pag. 21 di 26



SLUDGE PRODUCTION

Biological excess sludge productionTotal suspended solids KgSS/d 35571

Tertiary sludge ( from backwash sand filters )Total suspended solids KgSS/d 3085

Total sludge production KgSS/d 38656Dry solid percentage % DS 0,8Average quantity m³/d 4832

SLUDGE STORAGE TANKS (Gravity Thickener)

Data input

Total sludge production KgSS/d 38656Dry solid percentage % DS 0,8Average quantity m³/d 4832

Design parameters

- Thickening Type Gravity thickener- Range Dry Solid load KgSS/m².d 20 ÷ 40- Solids capture % > 95

Surface [calculated ] m² 1231Hydraulic depth m 4,5Volume [calculated] m³ 5540Units N° 4Thickener form CircularD Øi [calculated] m 19,8Equipment internal Vertical picket scraping

Selected dimensions

Units n° 4D unit Øi (chosen) m 20Hydraulic depth m 4,5Surface unit m² 314Volume unit m³ 1413Total surface m² 1256Total volume m³ 5652

Operating features

Dry Solid load KgSS/m².d 30,78Ritention time (hydraulic) days 1,17Ritention time (average) days 1,70

Sludge outlet KgSS/d 36722% DS 2m³/d 1836

Residual water m³/d 2996KgDS/d 1933

Thickening sludge pumping station

Pumps Type Horizontal CentrifugalUnits installed N° 2 +2 St-byCapacity m³/h 50÷200 (variation by mean frequency inverter )Head m. 5÷6Rated power kW 7,5

Pag. 22 di 26



AEROBIC DIGESTION

Data input

Sludge rate m³/d 1836Sludge concentration %DS 2Quantity of dry solid KgTSS/d 36722Volatile : 65÷70 % (VSSin) KgVSS/d 24788Mineral : 30÷35 % (MSSin) KgMSS/d 11935

Design parameters

Hydraulic retention time days ≥ 15Sludge age [SRT] days ≥ 15Volumetric load KgVSS/m³ ≤ 1,5Solid concentration KgTSS/m³ 20 ÷ 30Perfomance h SSV % 40 ÷ 50

V digestion [calculated] m³ 22850

Technical caracteristicsV digestion [Selected] m³ 23000Units n° 2V unit m³ 11500Hydraulic depth m 6,5Surface m² 1769

Operating features

� SSV (destr.) % ~ 45Solid concentration KgSST/m³ 20Digested sludge ( TSSout) KgSS/d 25568Sludge age SRT days 17,99Volumetric load KgVSS/m³ 1,078HRT (average) days 17,11

Q sludge outlet (QOUT) m³/d 852Solid concentration KgSST/m³ 30Humidity (U) % 97H2O residual m³/d 984

Oxygen demand

AOR -Operating condition (Verification)

(O2)op. = DO2/SSTin ×KgSSTin/dDO2/SSTin KgO2/KSST 0,6(O2)op. KgO2/d 22033

(O2)op [assumed] KgO2/d 22000 (as average value)(O2)op [assumed] KgO2/d 26400 (as peak value)

Oxygen transfert efficiency at Standard Condition (SOTE)[ Clear water , T°C = 20, P = 760 mm Hg , D.O. = 0 ppm ]

Aeration system type medium bubble diffusion air

� 0,65� 0,98Cs solubility O2 at Top ppm 9,17Cst solubility O2 atTst ppm 9,2Top °C 20Tst °C 20A = altitudine m 50Hi = hydraulic depth m 6,2

(O2)op.(O2)st. = --------------------------------------------- N/N � (1013,3 - 0,10133 × A + 98,1 × Hi/2 ) [ �× Cs ×------------------------------------------------ ] - O.D. 1013,3 N/N� = � × ------------------------------------------------------------------ × Theta (Top-Tst )

Cst

Pag. 23 di 26



D.O. = dissolved oxygen mg/l 2

N/N� [calculated] 0,681(O2)sote ( med) KgO2/d 32306(O2)sote ( peak) KgO2/d 38767

Diffuser type Membrane disc with EPDM rubberSize m 100( medium bubbles)Range operative diffusers m³/h >1,0 ÷ < 7Submergence m.c.w. 6,2Q air minimum diffuser m³/h > 2Q air max. diffuser m³/h < 4�st. Max (SOTE%) % 35�st. Minimo (SOTE%) % 30

QAIR in standard condition SOTR

QAIR daily/peak m³/d 320492 448689Operating hours/day 19QAIR average / peak m³/h 16868 23615N° diffusors installed N° 7000Type diffusion TapperedDistribution of diffusers N°/m² 2,05Flow rate diffuser [m3/h] min 2,41

max 3,37

Air production system

Intake Standard air condition T1 °C 45

°K 318 P1 mbar 1013Relative Humidity UR % 60Density �1 kg/m³ 1,085

CompressorsType Centrifugal single stage (*)N° compressors N° 3 +1RCapacity per units (max) m³/h 9381

assumed 9500Head mwc 7,2Absorbed power unit Kw 213Rated power unit Kw 250Total power installed Kw 1000Power specific abs kWh/m3 0,024

(*) Each compressor is design to supply air linear in the range from 40% to 100% of the max capacity

Digested sludge transfer pumps

Pumps Type Horizontal CentrifugalUnits installed N° 2 +1 St-byCapacity m³/h 50÷300 ( variable by means inverter )Head m. 20Rated power kW 18,5

Pag. 24 di 26



SLUDGE DRYING BEDS

Data input

Total sludge production m³/d 852Solid concentration KgSST/m³ 30Humidity (U) % 97

Design parameters

Specific surface m²/P.E. 0,2Surface beds ( Required) m² ~ 88000

Surface beds (Chosen) m² 88000Type drying beds Asphalt paved beds with drainage system

Operating features

Retention time Days ~ 52Q sludge outlet (QOUT) m³/d 31Solid concentration % 75Humidity (U) % 25Drenage H2O residual m³/d 123

Sludge cake containers

Type storage ContainerUnits N° 8Capacity each m³ 15Total capacity m³ 120

Pag. 25 di 26



RESIDUAL WATERS

All the residual waters of the plant (supernatants) are conveyed from the different plant sections to the inlet plant where they undergo all the treatment process.

From pre-thickening m³/d 2996From aerobic digestion m³/d 984From drying beds m³/d 123Various ( ~ 4%) m³/d 144Total Flow m³/d 4246

Increase % on QDW,d % ~ 3,86

Pumping station residual waterPumps Type submersibleUnits N° 2 + 1 St-byCapacity unit m³/h 300Head mwc 7 ÷ 9Rated power kW 15Absorbed power P1 kW 10,7

Pag. 26 di 26


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Calculo diseno MBR