SEWAGE TREATMENT PLANT TECHNOLOGY BY COMPLETE WATER SOLUTION BHALERAO HEIGHTS, AKURDI, PUNE

Transcription

1 SEWAGE TREATMENT PLANT TECHNOLOGY BY COMPLETE WATER SOLUTION BHALERAO HEIGHTS, AKURDI, PUNE

2 INTRODUCTION SEWAGE TREATMENT FACILITIES ARE LIMITED IN OUR COUNTRY AND MANY OF THE TREATMENT FACILITIES ARE NOT FUNCTIONING PROPERLY. THE ORGANIC POLLUTANT (MEASURED AS BOD/COD/SS) REMOVAL PERFORMANCES OF CONVENTIONAL TECHNOLOGIES EMPLOYED IN A MAJORITY OF STP S UNDER GAP (GANGA ACTION PLAN)/NRAP (NATIONAL RIVER ACTION PLAN) HAVE BEEN EXTENSIVELY STUDIED AND REPORTED. BUT MICROBIAL POLLUTANTS(MEASURED AS MPN OF TOTAL AND FECAL COLIFORMS ) REMOVAL PERFORMANCES ARE NOT GETTING MONITORED PROPERLY.

3 MINISTRY OF ENVIRONMENT & FOREST (MOEF) RECOMMENDATIONS MINISTRY OF ENVIRONMENT AND FOREST, GOVT. OF INDIA CONSTITUTED A COMMITTEE IN 1999 TO RECOMMEND COLIFORM STANDARDS FOR TREATED SEWAGE DISCHARGED INTO THE RIVERS AND LAKES. PARAMETER NOT TO EXCEED DISCHARGE INTO/ON BOD (mg/l) 30 WATER BODY BOD (mg/l) 100 LAND FOR IRRIGATION TSS (mg/l) 50 WATER BODY TSS (mg/l) 200 LAND FOR IRRIGATION FECAL COLIFORM (MPN/100 ML) 1000 DESIRABLE MAX PERMISSIBLE WATER BODY OR FOR AGRICULTURE AND AQUACULTURE

4 SEWAGE TREATMENT PROCESS SELECTION TREATED SEWAGE QUALITY : MEET STD. AS PER PCB (POLLUTION CONTROL BOARD). POWER REQUIREMENT : MINIMIZE LAND REQUIREMENT : MINIMIZE CAPITAL COST : OPTIMUM UTILIZATION O&M COST : LOWER RUNNING COST

5 TYPES OF TREATMENT PROCESSES ASP ACTIVATED SLUDGE PROCESS. MBBR MOVING BED BIO REACTOR. FAB FLUIDISED AERATED BED. SAFF SUBMERGED AERATION FIXED FILM SBR SEQUENTIAL BATCH REACTOR. MBR MEMBRANE BIO REACTOR. EA EXTENDED AERATION.

6 GENERAL PROCESS FLOW DIAGRAM SEWAGE INLET BAR SCREEN CHAMBER OIL & GREASE TRAP EQUALIZATION TANK AERATION TANK TREATED WATER TANK ACTIVATED CARBON FILTER PRESSURE SAND FILTER FILTER FEED TANK SETTLING TANK FOR FLUSHING & GARDENING DISINFECTION SYSTEM EXCESS SLUDGE TO DISPOSAL SLUDGE HOLDING TANK

7 GENERAL PROCESS DESCRIPTION SEWAGE IS FED TO THE SCREENING CHAMBER TO REMOVE THE FLOATING MATERIALS AND THEN ENTRAINED TO OIL AND GREASE TRAP FOR OIL REMOVAL WHICH CAME ALONG WITH SEWAGE FROM THE PANTRIES OR KITCHENS. THE SCREENED SEWAGE IS THEN INTRODUCED TO THE EQUALIZATION TANK OR COLLECTION TANK BY GRAVITY FLOW. THIS UNIFORMED SEWAGE IS PUMPED TO THE AERATION TANK TO REDUCE THE BOD LOAD, TO MAINTAIN THE MLSS CONCENTRATION AND TO GENERATE THE MICROBES OR SLUDGE. AERATION IS PROVIDED WITH THE HELP OF DIFFUSERS AND AIR BLOWER. AERATED SEWAGE IS THEN FURTHER PASSED TO THE SETTLING TANK BY GRAVITY FLOW. SINCE THIS TANK IS HOPPER BOTTOM/CONICAL BOTTOM, SLUDGE IS SETTLED AT THE BOTTOM OF THE TANK. GRAVITY FLOW FROM THE FROM SETTLING TANK, THE SUPERNATANT IS ENTRAINED TO THE FILTER FEED TANK OR INTERMEDIATE STORAGE TANK.

8 PROCESS DESCRIPTION CONTD. SECONDARY TREATED WATER IS PASSED TO THE ACTIVATED CARBON FILTER FOLLOWED BY PRESSURE SAND FILTER TO REMOVE THE COLOR AND ODOR, SUSPENDED SOLID PARTICLES RESPECTIVELY. THE PURPOSE OF DISINFECTION IN THE TREATMENT IS TO SUBSTANTIALLY REDUCE THE NUMBER OF MICRO-ORGANISMS IN THE WATER. FILTERED WATER IS THEN COLLECTED TO THE FINAL STORAGE TANK OR TREATED WATER TANK, WHERE IT WILL BE DESIRED FOR NON POTABLE APPLICATIONS. THE BACKWASHED WATER FROM THE FILTERS IS RETURNED TO THE EQUALIZATION TANK. SETTLED SLUDGE FROM THE SETTLING TANK WILL BE REMOVED BY PUMPING TO THE SLUDGE HOLDING TANK WHERE SOME QUANTITY OF SLUDGE IS RETURNED TO THE EQUALIZATION TANK AND EXCESS SLUDGE IS FED TO DISPOSAL UNIT LIKE FILTER PRESS OR CENTRIFUGE, ETC..

9 NITRIFICATION AND DE-NITRIFICATION NITRIFICATION-DE-NITRIFICATION IS ONE OF THE MOST WIDELY ACCEPTED BIOLOGICAL SOLUTIONS TO THE PROBLEM OF NITROGEN REMOVAL FROM HIGH STRENGTH NITROGENOUS WASTEWATERS DUE TO ITS EFFICIENCY AND ECONOMY. NITRIFICATION IS A TWO STEP SEQUENTIAL AEROBIC OXIDATIVE PATHWAY FOR THE OXIDATION OF AMMONIA TO NITRATE, RESULTING IN RELEASE OF ENERGY. THE REACTION IS CARRIED OUT BY AUTOTROPHIC BACTERIA BELONGING TO THE GENERAL NITROSOMONAS (OXIDIZING AMMONIA TO NITRITE) AND NITROBACTER (OXIDISING NITRITE TO NITRATE).

10 NITRIFICATION AND DE-NITRIFICATION DE-NITRIFICATION IS AN ANOXIC\ANAEROBIC REDUCTIVE PATHWAY FOR THE CONVERSION OF NITRATE TO NITROGEN GAS. THIS REACTION IS CARRIED OUT BY BACTERIA BELONGING TO GENERAL BACILLUS, PSEUDOMONAS, ACHROMOBACTER, MICROCOCCUS, ETC. HOWEVER SIMULTANEOUS NITRIFICATION- AEROBIC DE-NITRIFICATION SYSTEM IN A SINGLE STAGE USING A MIXED BIOFILM CULTURE OF THIOSPHAERA PANTOTROPHA CAN ALSO BE USED. THUS ELIMINATING THE REQUIREMENT OF A SEPARATE ANOXIC REACTOR FOR DE-NITRIFICATION.

11 EFFICIENCY OF NITRIFICATION AND DE-NITRIFICATION ON THE BASIS OF HRT : REMOVAL EFFICIENCY INCREASE WITH INCREASE OF HRT. ON THE BASIS OF SURFACE LOADING : REMOVAL EFFICIENCY DECREASE WITH INCREASE SURFACE LOADING. THE PH WAS MAINTAINED BETWEEN WHICH IS IN OPTIMUM FOR BOTH NITRIFICATION AND DE NITRIFICATION.

12 1. ASP ACTIVATED SLUDGE PROCESS o IT IS A CONVENTIONAL PROCESS. o PROVEN AND TESTED METHODOLOGY ALL OVER THE WORLD FOR THE LAST 7 8 DECADES. o SEVERAL MODIFICATIONS AVAILABLE FOR SPECIFIC REQUIREMENTS. o UNINTERRUPTED POWER SUPPLY REQUIRED FOR AERATION AND SLUDGE RECIRCULATION. o REACTOR SLUDGE LEVELS TO BE CAREFULLY MONITORED AND SLUDGE IS TO BE WITHDRAWN FROM THE SYSTEM. o 80 90% REMOVAL OF BACTERIA. o 90 99% REMOVAL OF VIRUSES.

13

14 2. MBBR MOVING BED BIO REACTOR o MBBR TECHNOLOGY IS PREDOMINANTLY USED FOR ACHIEVING A HIGH AND PREDICTABLE LEVEL OF BIOLOGICAL WASTEWATER TREATMENT. o TO HAVE ECO FRIENDLY AND NATURAL TREATMENT, STP IS DESIGNED BASED ON THE BIOLOGICAL TREATMENT CONCEPT. o THIS MEANS NATURALLY OCCURRING MICROBES (WHICH ARE PRESENT IN SEWAGE WATER ITSELF) REMOVES OR DEGRADE THE ORGANIC MATTER PRESENT IN THE SEWAGE & AT THE END CLEAN WATER IS AVAILABLE.

15 MBBR MEDIA

16 PROCESS FLOW DIAGRAM

17 THANK YOU