Pollution Control with Profit from Dairy Waste
By Anaerobic Process using UASB

UASB SYSTEM
• Upflow fluidised bed single stage reactor with granulation of anaerobic bacteria as media.
• Reactor consists of tank in RCC of 4 to 6 depth and suitably designed diameter.
• Effluent is evenly distributed at bottom and flows up through a bed of anaerobic
sludge during which degradable matter is digested.
• Dissolved organic matter is removed by anaerobic bacteria.
• This is converted to biogas + new cells.
• Gas formed is collected at top portion by gas liquid solid separator.
• Liquid flows out and any sludge is trapped and flows down back to the blanket.

SALIENT FEATURES
• COD Reduction : 80 – 85%
• Biogas generated : 0.5 to 0.55 m3 kg COD reduced
• Detention time : 10-12 hrs
• Organic loading : 4-5 kg/m3
• Anaerobic process thus oxygen from external source not required and no limitation of a transfer of oxygen which is sparingly soluble.
• Higher loading rate, upto 15 kg/m3, thus area requirement drastically reduces.
• Practically no power requirement since no internal mixing /aeration required.
• Generation of methane rich biogas which can be used to generate power.
• Minimal sludge production due to higher sludge retention time.

Cost-Benefit Analysis

INPUT

• COD : 2500 ppm
• FLOW : 1200 m3/day Dairy Waste

COST ANANLYSIS :

COST ANANLYSIS :

Annualised capital cost = C [ i(1+i)n]
                                    (1+i)n – 1

                                    = 54 [0.135 (1.135)15]
                                    [ (1.135)15-1]

                                    = 8.50 lakhs
( C = Capital Cost = Rs. 54 lakhs, i = rate of Interest = 13.5%, n = Life of reactor = 15 yrs.)

O & M Cost                 = Rs. 17.5 lakhs /annum
                                    (Manpower + 50 HP+ spare part)

Annualised Cost           = O& M + Annual Capital
                                    = 17.5 + 8.50 lakhs/annum
                                    = Rs. 26.00 lakhs/annum.

RECOVERY : Recovering is worked out based on 24 hrs. operation of dual fuel engine.

Recovery in terms of biogas as        = 1200 m3/d x 2 kg/ m3 x 0.54 m3 biogas/COD destroyed
                                                      generation of power x 0.8 COD destroyed/Kg x 365
                                                      = 3,78,432 m3 of biogas/year
                                                      = 3,78,432 x 1.4 KWH / year
                                                      = 5,29,804.8 KWH /year x Rs. 4.0 /KWH
                                                      = Rs. 21.2 lakhs.

Recovery due to water recycling    = 300 m3/ day x 25 Rs/ m3 x 365
                                                     = Rs. 27.37 lakhs

Payback period                           = Capital cost / (Recovery in terms of electricity & water – Annualised cost)
                                                   = 54 / (27.37 + 21.2 – 26.00)
                                                   = 2.5 years.

SOME OF OUR COMPLETED PROJECTS Data

• Mahananda Dairy, Goregaon, Mumbai.

• Gokul Dairy, Kolhapur, Maharashtra.

• National Dairy Development Board, Bangalore.

• Pradeshik Co-Op. Dairy Federation Ltd., Lakhanow, U.P.

• Hassan Dairy, Karnataka.

• Hosakote Dairy, Karnat