Masasumi Kawamura

Development of an expanded-bed GAC reactor for anaerobic treatment of terephthalate-containing wastewater

An expanded-bed granular activated carbon (GAC) anaerobic reactor was developed to treat terephthalate-containing wastewater. Terephthalate inhibits biological anaerobic degradation of terephthalate and methane production when present at a concentration of more than 150 mg/L. In the GAC anaerobic reactor developed here, degradation of terephthalate and other organic compounds occurred smoothly and stably with removal and methane fermentation ratios of more than 90% under a chemical oxygen demand (COD) loading rate of 4 kg COD/(m(3) d) and a terephthalate loading rate of 1 kg terephthalate/(m(3) d).

Study on the Treatment of Wastewater Containing Chloroacetaldehyde by Biological Expanded-bed GAC Anaerobic Reactor.

Expanded-bed granular activated carbon (GAC) anaerobic reactor was applied to treat artificial wastewater which contains high concentration of chloroacetaldehyde as well as sodium acetate. Organic loadings were changed from 1.0 to 6.1g-CODcr·kg-1-GAC·d-1 by changing concentrations of organics (from 90 to 900 mg·l-1 for chloroacetaldehyde, and from 1,000 to 2,000 mg·l-1 for sodium acetate). Hydraulic retention time was changed from 2.2 to 1.1 days based on expanded-bed volume. The operation of the reactor was successfully started without any dilution of the wastewater and the reactor could respond without any deterioration of treatment efficiency to shock load by the adsorption ability of GAC used as attached medium. COD and chloroacetaldehyde removal efficiencies were kept more than 87% and 97% respectively. Biomass in the reactor was 114μgDNA·g-1-GAC, which corresponds to 2,000 mgVSS·l-1 based on the expanded-bed volume.