Anaerobic Biodegradation Of Tar-containing Wastewater From Gasification Of Biomass For Power Production

In the research reported in this paper , anaerobic toxicity assay (ATA) of tar-containing wastewater from gasification of biomass was conducted i and the availability of its anaerobic treatment was studied in a lab-scale upflow blanket filter(UBF).In addition, the factors effecting acclimation and granulation in the DBF were studied, and the treatment efficiency of UBF reactor treating tar-containing wastewater was analysed in the paper.The anaerobic toxicity assay results shown that the tar-containing wastewater was toxic to anaerobic bacteria .The IC50% value of the tar-containing wastewater was 418 mg COD /L. The toxic mechanism varied for the wastewater concentrations .The tar-containing wastewater belonged to metabolic toxin with its concentration lower than 293 mg/L, physiological toxin with its concentration of 587 mg/L, and bactericidal toxin with its concentration over 879 mg/L.In the study of availability of anaerobic treatment of tar-containing wastewater from gasification of biomass. the granulation and acclimation was achieved in the UBF reactor in 274 days at ambient temperature of 16~36癈.The amount of tar-containing wastewater was the main effect factors in the granulation and acclimation process.Under stable processing condition , the removal of COD was about 26% in the UBF reactor treating tar-containing wastewater with HRT of 66.9 h and OLR of 0.65 ~ 0.75kgCOD/m3 ?d. The treatment efficiency of the UBF was low , which shown that anaerobic treatment can do as pretreatment only and other treatment processes were needed to meet the requirements of water recycle use in the production .