![Degradation of chlorpyrifos contaminated soil by bioslurry reactor operated in sequencing batch mode: bioprocess monitoring [An article from: Journal of Hazardous Materials]](https://www.ebooknetworking.net/books/B00/0RR/bigB000RR45ZC.jpg)
Degradation of chlorpyrifos contaminated soil by bioslurry reactor operated in sequencing batch mode: bioprocess monitoring [An article from: Journal of Hazardous Materials]
Description
This digital document is a journal article from Journal of Hazardous Materials, published by Elsevier in 2004. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.
Description:
Bioslurry reactor (SS-SBR) was studied for the degradation of chlorpyrifos contaminated soil using native mixed microflora, by adopting sequencing batch mode (anoxic-aerobic-anoxic) operation. Reactor operation was monitored for a total cycle period of 72h consisting of 3h of FILL, 64h REACT, 2h of SETTLE, and 3h of DECANT with chlorpyrifos concentrations of 3000@mg/g, 6000@mg/g and 12000@mg/g. At 3000@mg/g of chlorpyrifos concentration, 91% was degraded after 72h of the cycle period, whereas in the case of 6000@mg/g of chlorpyrifos, 82.5% was degraded. However, for 12000@mg/g of chlorpyrifos, only 14.5% degradation was observed. The degradation rate was rapid at lower substrate concentration and 12000@mg/g of substrate concentration was found to be inhibitory. Chlorpyrifos removal rate was slow during the initial phase of the sequence operation. Half-life of chlorpyrifos degradation (t"0"."5) was estimated to be 6.3h for 3000@mg/g of substrate, 17.5h for 6000@mg/g and 732.2h for 12000@mg/g. Process performance was assessed by monitoring chlorpyrifos concentration and biochemical process parameters viz., pH, oxidation and reduction potential (ORP), dissolved oxygen (DO), oxygen consumption rate (OCR) and microbial count (CFU) during sequence operation. From the experimental data obtained it can be concluded that the rate-limiting step with the bioslurry phase reactor in the process of chlorpyrifos degradation may be attributed to the concentration of substrate present in either soil or liquid phase. Periodic operations (SBR) by varying individual components of substrate with time in each process step place micro-organisms under nutritional changes from feast to famine and maintains a wide distribution in the population of micro-organisms resulting in high uptake of the substrate in the bioslurry reactor.
Description:
Bioslurry reactor (SS-SBR) was studied for the degradation of chlorpyrifos contaminated soil using native mixed microflora, by adopting sequencing batch mode (anoxic-aerobic-anoxic) operation. Reactor operation was monitored for a total cycle period of 72h consisting of 3h of FILL, 64h REACT, 2h of SETTLE, and 3h of DECANT with chlorpyrifos concentrations of 3000@mg/g, 6000@mg/g and 12000@mg/g. At 3000@mg/g of chlorpyrifos concentration, 91% was degraded after 72h of the cycle period, whereas in the case of 6000@mg/g of chlorpyrifos, 82.5% was degraded. However, for 12000@mg/g of chlorpyrifos, only 14.5% degradation was observed. The degradation rate was rapid at lower substrate concentration and 12000@mg/g of substrate concentration was found to be inhibitory. Chlorpyrifos removal rate was slow during the initial phase of the sequence operation. Half-life of chlorpyrifos degradation (t"0"."5) was estimated to be 6.3h for 3000@mg/g of substrate, 17.5h for 6000@mg/g and 732.2h for 12000@mg/g. Process performance was assessed by monitoring chlorpyrifos concentration and biochemical process parameters viz., pH, oxidation and reduction potential (ORP), dissolved oxygen (DO), oxygen consumption rate (OCR) and microbial count (CFU) during sequence operation. From the experimental data obtained it can be concluded that the rate-limiting step with the bioslurry phase reactor in the process of chlorpyrifos degradation may be attributed to the concentration of substrate present in either soil or liquid phase. Periodic operations (SBR) by varying individual components of substrate with time in each process step place micro-organisms under nutritional changes from feast to famine and maintains a wide distribution in the population of micro-organisms resulting in high uptake of the substrate in the bioslurry reactor.
