ETP For Food and Beverage Industry
INFLUENT TYPES & CHARACTERISTICS
In food Industry, two types of streams get collected in ETP.:
One stream consists of low TDS and TSS, COD, BOD, potato peel, pH etc. and is majorly known as starch water stream.
Whereas second stream that is mainly washing & CIP has high TDS, FOG, TSS, COD, BOD and pH less than 7.
TREATMENT SCHEME
PRELIMINARY TREATMENT
1) Screening & Pre sedimentation & Oil and Grit removal:
Screening for removing major particals. Primary sedimentation removes suspended solids and floating organic material coming in washing effluent.
2) For process effluent – Screening & Mechanical Screen:
For removing solid partials like large or small potato pills etc.
3)For CIP effluent –Screening & Oil and Grit separator:
For removing Oil from CIP Effluent
EQUALIZATION TANK
Equalization is done to serve one simple purpose of providing Linear propagating feed to downstream process at Constant Flow. Placement of an equalization tank following primary treatment minimizes operation and maintenance, and minimizes requirements for solids removal, aeration, and Odor control equipment.
PIPE FLOCULATOR:
In a Pipe flocculator, the mixing energy for flocculation is obtained by the turbulence in the mixing unit and the pipe. A coagulant is usually dosed to the raw water at the inlet of the PFR. Immediately after the dosing point a mixing unit is installed for the mixing of coagulant and raw water.
DESOLVE AIR FLOTATION
DAF is compact & efficient gravity separation device that guarantee at least 85-90% removal of oil and solids. Suspended solids, grease and oil are very efficiently removed by DAF, and a combination of screening and DAF results in BOD / COD removals up to 60% depending on the application.The flotation unit is a high-built open tank separator for dissolved air assisted separation of floc from water.
BUFFER TANK:
The objective of the buffer tank is to minimize or control fluctuations in wastewater flow & characteristics in order to provide optimum conditions for biological processes. The buffer tank will be of a sufficient size to adequately absorb wastewater fluctuations caused by variation in plant production scheduling and to dampen the concentrated batches periodically dumped or spilled. The entire content of the effluent will be kept in mix condition by air blower.
SECONDARY TREATMENT
1) Screening & Pre sedimentation & Oil and Grit removal:
Screening for removing major particals. Primary sedimentation removes suspended solids and floating organic material coming in washing effluent.
2) For process effluent – Screening & Mechanical Screen:
For removing solid partials like large or small potato pills etc.
3)For CIP effluent –Screening & Oil and Grit separator:
For removing Oil from CIP Effluent
ANAEROBIC TREATMENT:
The anaerobic waste treatment process is an effective method for the treatment of many organic wastes. The treatment has a number of advantages over aerobic treatment process, namely,
- The energy input of the system is low as no energy is required for oxygenation,
- Lower production of excess sludge (biological synthesis) per unit mass of substrate utilized,
- Lower nutrient requirement due to lower biological synthesis, and
- Degradation leads to production of biogas which is a valuable source of energy.
CONTINOUES STIRRING TANK REACTOR (CSTR):
In CSTR reactor the raw waste is introduced from top of the reactor. The recycled sludge is also introduced from the top of the reactor. This mixed liquor travels downward through the central shaft. In this central shaft, agitator provides adequate mixing of raw waste and recycled sludge. From central shaft liquor enters reactor near bottom of tank The treated effluent of CSTR reactor is discharged from the top of reactor to utilize head available. The gas will be carried through a gas line equipped with safety devices and burnt at the flare stack.
CROSS FLOW SEPARATOR (CFS)
The cross-flow plate pack consist of a number corrugated plates mounted parallel to each other at spacing of 2-8 cm based on application. The wastewater containing the floating material and suspended solids passes in horizontal direction between the plates. Laminar flow conditions are established while the water flows across the pack from the inlet to the outlet.
DENITRIFICATION
Denitrification is a process where Bacteria use nitrates (NO3) for oxygen. Denitrification is an anoxic process performed by heterotrophic bacteria using nitrite and/or nitrate as the electron acceptor. In this process, NO3− is reduced to NO2− and then to nitric oxide (NO), nitrous oxide (N2O) and finally to N2.
NH4+ + 2O2 → NO3- + 2H+ +H2O
AERATION SYSTEM FOLLOWED BY SECONDARY CLARIFIER
Here we are using Diffused aeration system for remaining BOD & COD Removal according to the Mass balance diagram. Aeration is a process where Bacteria grow using the oxygen. And for that we have supply extra air through Air Blower according to their oxygen demand.
FILTRATION SYSTEM :
PRESSURE SEND FILTER & ACTIVATED CARBON FILTER
PSF & ACF is a also called as polishing treatment. These Filters are designed to remove turbidity and suspended particles present in the feed water with minimum pressure drop.