Two novel biogas upgrading strategies that recover high-value chemicals or CO2 liquid fertilizer from biogas besides biomethane were evaluated from the view of global warming potential (GWP) through life cycle assessment in comparison with conventional approaches. Results show that the scenarios producing biomethane with nano calcium carbonate or CO2 liquid fertilizer from biogas present significantly lower GWP (-3.4 kgCO2-eq/Nm3-biogas and -4.4 kgCO2-eq/Nm3-biogas, respectively), compared to combined heat and power scenario (-2.4 kgCO2-eq/Nm3-biogas) and biogas upgrading by high pressure water scrubbing scenario (-1.3 kgCO2-eq/Nm3-biogas). The carbon sequestration and utilization from CO2-rich water significantly enhanced carbon reduction in overall biogas management. Furthermore, considering cleaner electricity in the future, strategies focusing on managing biogas for materials will align more with climate change goals than energy-focused strategies. This study provides insight for decision-makers in developing roadmaps for carbon reduction pathways in biogas-relating sectors.

采用"厌氧消化—A/O—臭氧催化氧化—BAF"组合工艺对某农药企业污水处理站生化出水进行中试研究.中试装置设计处理规模为12 t/d,进水水质主要指标:COD为214～346 mg/L,ρ(NH3-N)为8～35 mg/L,TN为65～108 mg/L.经组合工艺处理后,出水COD为51.2～71.4 mg/L,ρ(NH3-N)为2.4～6.8 mg/L,TN为13.6～19.2 mg/L,出水水质可达到江苏省《化学工业主要水污染物排放标准》(DB 32/939—2006)中的一级标准.整套工艺对进水具有较强的耐冲击负荷能力,可适应难降解、高氮废水,具有较好的经济效益.

随着城市化进程的加快,我国剩余活性污泥的产生量逐年增加,活性污泥中的胞外聚合物EPS含黏性蛋白类物质并高度亲水,因此破坏污泥絮体、释放和水解黏性有机物是改善污泥脱水性能的有效途径.通过分析水热碳化调理前后污泥比阻(SRF)、黏度(μ)、絮体形态特征及上清液的理化性质,考察了温度、时间以及促进剂Fe2(SO4)3对水热碳化污泥脱水性能的影响.结果 表明:反应温度为220℃、反应时间为2h、Fe2(SO4)3浓度为0.5 mol/L时的水热碳化处理,污泥的脱水性能最好,比阻和黏度分别比对照组降低了97.7％和98.7％.水热碳化的高温高压环境破坏了污泥的絮体,使污泥胶体结构的内聚力降低,污泥的脱水性能得到改善.

随着经济的发展和国民生活水平的提高,污水污泥的排放量逐年增加,环境问题愈发严重,污泥的处理处置成为焦点问题,污泥脱水是制约污泥处置处理进一步发展的关键.本文针对目前污泥深度脱水技术开展,首先简述了不同来源污泥的分类及其基本特性,然后重点阐述了不同污泥预处理技术,分析了各污泥深度脱水技术作用机理,并对各自脱水效果及优缺点进行比较分析.结果表明,物理法中水热预处理对污泥的可脱水程度提升最大.较低声强、短时间的超声波处理对污泥脱水性能有着明显的改善.化学法在污泥过滤性能以及脱水速率方面有很大优势,酸碱处理后污泥zeta电位上升,污泥过滤性能及脱水速率得到改善.高级氧化法处理后污泥脱水效果高于酸碱处理,微生物细胞被溶解释放出有机物,可脱水程度改善.生物法处理污泥除改善污泥脱水性能外,还有对环境污染小等特点,但耗时较长.最后对污泥的后续脱水工艺进行综述,介绍了现存的主流脱水工艺,包括机械脱水、热干化技术、水热脱水工艺等;并针对不同的污泥后续利用方法,选取合适的预处理技术,提出相应优化的污泥处理工艺流程.

With the improvement of drinking w ater quality standard,in order to solve problem of the poor effect of conventional processes for treating underground source of water,a pilot exper-iment w as conducted on sand filter and biological activated carbon and their combined process.T he removal efficiency of iron,manganese,ammonia nitrogen,turbidity and visible substances in un-derground source of water by dissolved the process was investigated.Optimum process and optimal parameters were found.The results showed that sand filter and biological activated carbon com-bined process was the best.The effluent iron,manganese,ammonia nitrogen,turbidity and chro-maticity were <0.05 mg/L,<0.03 mg/L,<0.1 mg/L,<0.2 NTU,<5°.The effluent quality met the requirements of Standards f or Drinking W ater Quality(GB 5749-2006).

The effects of polymerization ferrous sulfate (PFS),polyacrylamide (PAM),polyaluminum chloride (PAC) and Fenton reagents on petrochemical industry sludge dewaterability was investigated in this study,then the anaerobic sludge underwent pressed filtration by the frame filter.The sludge dewaterability in Fenton reagent conditioned system was better than the PFS,PAC and PAM conditioned system.In the sludge system,with 15,20,25 g/L of ferrous sulfate heptahydrate and 5 mL/L of H2O2 added,capillary suction time (CST) of sludge was reduced to 36.82,18.3,27.28 s,and the specific resistance to filtration (SRF) of sludge was reduced to 4.22 × 1011,1.23 × 1011,2.45 × 1011 cm/g,respectively.After filter press dewatering,the solid content of the sludge cake was 68.65％,64.19％,67.21％,57.46％,55.83％ and 59.36％ in the sludge conditioning by FPS,PAC,PAM,Fenton 15-5 (15 g/L ferrous sulfate heptahydrate and 5 mL/L H2O2),fenton20-5 (20 g/L ferrous sulfate heptahydrate and 5 mL/L H2O2) and Fenton 25-5 (25 g/L ferrous sulfate heptahydrate and 5 mL/L H2O2),respectively.Thus,the optimal dewatering conditioner of petrochemical anaerobic sludge was Fenton 20-5.This study is of practical value for the petrochemical anaerobic sludge dehydration and reduction.

Based on the charac teristics of water quality of the secondary biochemical effluent from pharmaceutical fermentation,three-dimension electrolytic technology has been used for the advanced wastewater treatment,under laboratory conditions. By single-factor and orthogonal tests, the effects of pH,current density,activated carbon dosage,reaction time,etc. on the treatment efficiency are investigated. The results show that the optimal reaction conditions of three-dimension electrolysis are as follows:electrolysis time is 40 min,current density 50 mA/cm2,pH=3,and activated carbon dosage 15 g/L. After the electrolyzed effluent has been treated by activated sludge process ,it can meet the requirements of the Discharge Standard of the Pollutants in Industrial Wastewater from Pharmaceutical Fermentation(GB 21903-2008).