生物质气化工艺废水特征及预处理实验研究

对生物质气化中试现场产生的废水进行了水质及水量特征分析,针对生物质气化工艺废水固体颗粒含量高、有机物浓度高、难生化降解、废水增量少的特点,采取减压蒸馏及芬顿氧化对生物质气化废水进行预处理。实验结果表明,在85 ~ 90℃、真空度 -0.07 ~ -0.095 MPa减压蒸馏条件下,废水COD、NH₄-N脱除率分别为74.38%、94.46%;在Fe²⁺-H₂O₂体系中,考察了H₂O₂与废水质量比、H₂O₂与Fe²⁺摩尔比、反应时间、H₂O₂浓度对COD、NH₄-N、TOC、TN等的影响,当H₂O₂与废水质量比为8.40%时,可将减压蒸馏蒸出液COD从2.05 × 10⁴ mg/L降至4.11 × 10³ mg/L,NH₄⁺-N从143 mg/L降至11.1 mg/L。

Experimental Study on Characteristics and Pretreatment of Wastewater from Biomass Gasification Process

Analysis of quality and quantity of the waste water generated from the pilot biomass gasification plant were performed. According to the characteristics of high solid particle content, high organic matter concentration, difficult biodegradation, and small increase of waste water in the biomass gasification process, vacuum distillation and Fenton oxidation were used to pre-process the biomass gasification wastewater. Experimental results showed that under the conditions of 85-90^oC and vacuum degree of -0.095 - -0.07 MPa, the COD and NH₄-N removal efficiencies were 74.38% and 94.46% respectively. In the Fe²⁺-H₂O₂ system, the effects of factors such as the mass ratio of H₂O₂ to wastewater, the molar ratio of H₂O₂ to Fe²⁺, the reaction time, and the concentration of H₂O₂ on COD, NH₄-N, TOC, and TN were investigated. When the mass ratio of H₂O₂ to wastewater was 8.40%, the COD of the distillated wastewater under reduced pressure was reduced from 2.05×10⁴ mg/L to 4.11 × 10³ mg/L, and NH₄-N was reduced from 143 mg/L to 11.1 mg/L.