A new anaerobic reactor, Jet-loop anaerobic fluidized bed （JLAFB）, was designed for treating high-sulfate wastewater. The treatment characteristics, including the effect of influent COD/SO42 ratio and alkalinity and...A new anaerobic reactor, Jet-loop anaerobic fluidized bed （JLAFB）, was designed for treating high-sulfate wastewater. The treatment characteristics, including the effect of influent COD/SO42 ratio and alkalinity and sulfide inhibition in reactors, were discussed for a JLAFB and a general anaerobic fiuidized bed （AFB） reactor used as sulfate-reducing phase and methane-producing phase, respectively, in two-phase anaerobic digestion process. The formation of granules in the two reactors was also examined. The results indicated that COD and sulfate removal had different demand of influent COD/SO4^2- ratios. When total COD removal was up to 85%, the ratio was only required up to 1.2, whereas, total sulfate removal up to 95% required it exceeding 3.0. The alkalinity in the two reactors increased linearly with the growth of influent alkalinity. Moreover, the change of influent alkalinity had no significant effect on pH and volatile fatty acids （VFA） in the two reactors. Influent alkalinity kept at 400-500 mg/L could meet the requirement of the treating process. The JLAFB reactor had great advantage in avoiding sulfide and free-H2S accumulation and toxicity inhibition on microorganisms. When sulfate loading rate was up to 8. 1 kg/（m^3.d）, the sulfide and free-H2S concentrations in JLAFB reactor were 58.6 and 49.7 mg/L, respectively. Furthermore, the granules, with offwhite color, ellipse shape and diameters of 1.0-3.0 mm, could be developed in JLAFB reactor. In granules, different groups of bacteria were distributed in different layers, and some inorganic metal compounds such as Fe, Ca, Mg etc. were found.展开更多
在"水解溶出+UASB反应器"处理城镇有机垃圾的两相厌氧系统中,向UASB反应器进水中添加K、Mg、Fe、Co、Ni 5种金属离子的组合促进剂,通过对UASB反应器容积负荷、产气量、产甲烷量在添加组合促进剂前后的比较,研究了组合促进剂(K...在"水解溶出+UASB反应器"处理城镇有机垃圾的两相厌氧系统中,向UASB反应器进水中添加K、Mg、Fe、Co、Ni 5种金属离子的组合促进剂,通过对UASB反应器容积负荷、产气量、产甲烷量在添加组合促进剂前后的比较,研究了组合促进剂(K、Mg、Fe、Co、Ni)对有机垃圾浸出液厌氧消化过程的促进作用。试验结果表明,添加组合促进剂后,反应器的平均容积负荷从12.89 kg COD/m3.d提高到17.79 kg COD/m3.d;平均污泥负荷从0.82 kg COD/kg VSS.d提高到1.07 kg COD/kg VSS.d。此外,平均每千克COD产气量为392.5 L,比添加组合促进剂之前增大了6.4%;而平均每千克COD产甲烷量为297.5 L,比添加组合促进剂之前增大了10.5%。对于氨氮、挥发性脂肪酸(VFA)、pH及碱度来说,在添加组合促进剂之后则无大的变化。展开更多
以人工合成硫酸盐废水为基质,采用硫酸盐还原—气提脱硫—甲烷化的串联工艺,考察了硫酸盐还原相反应器和气提脱硫反应器的处理效果,并探讨了整个串联工艺系统的最佳工艺条件。结果表明:(1)硫酸盐还原相中SO42-负荷在回流比为15:1的情况...以人工合成硫酸盐废水为基质,采用硫酸盐还原—气提脱硫—甲烷化的串联工艺,考察了硫酸盐还原相反应器和气提脱硫反应器的处理效果,并探讨了整个串联工艺系统的最佳工艺条件。结果表明:(1)硫酸盐还原相中SO42-负荷在回流比为15:1的情况下可达到10.5 kg SO42-/(m.3d),同时对SO42-的还原率保持在80%以上;(2)气提脱硫器效果显著,对硫化物的去除率在90%以上,出水硫化物含量<50 mg/L,不会对后续反应产生影响;(3)产甲烷相中COD负荷达到15kgCOD/(m.3d)时,去除率保持在85%以上;(4)进水废水pH在8.0左右时,反应器可获得最高的硫酸盐去除率并使出水中硫酸盐浓度在国家规定标准以下;(5)当COD/SO42-比值达到3时,系统对负荷的冲击仍有较强的耐受能力。整体工艺对SO42-的还原率达到90%以上,COD去除率在94%左右,该系统最终实现了硫酸盐及有机物有效去除的双重目标。展开更多
A two-phase anaerobic reactor fed with glucose substrate（3 g chemical oxygen demand（COD）/L） was used to investigate the effects of toxic metals on the degradation of organics and the soluble microbial product（SMP...A two-phase anaerobic reactor fed with glucose substrate（3 g chemical oxygen demand（COD）/L） was used to investigate the effects of toxic metals on the degradation of organics and the soluble microbial product（SMP） formation. Low concentrations of Ni（II）（5 and10 mg/L） promoted the acid phase, whereas high concentrations（15, 20, and 25 mg/L）exhibited an inhibitory effect on, but did not alter the fermentative method, which mainly involved the fermentation of propionic acid. The methanogenic microorganism exhibited a strong capability adapting constantly increased Ni（II） levels. The acid phase was an accumulation stage of SMP. In the absence of Ni（II）, the high-molecular-weight material in the effluent SMP mainly contained polysaccharide, tryptophan, and casein. Methanogens metabolized most of the polysaccharide, the whole tryptophan content, and part of the casein, leading to the presence of humic acid and protein in effluent. After Ni（II） dosage, the protein and polysaccharide of the acid phase increased, and tryptophan changed, while casein remained stable. More protein than polysaccharide was produced, suggesting the prominent function of protein when addressing the negative effect of toxic metals. The analysis of DNA confirmed the change of bacterial activity.展开更多
基金Project supported by the National Natural Science Foundation of China(No. 50278036)the Natural Science Foundation of Guangdong Province (No. 04105951)
文摘A new anaerobic reactor, Jet-loop anaerobic fluidized bed （JLAFB）, was designed for treating high-sulfate wastewater. The treatment characteristics, including the effect of influent COD/SO42 ratio and alkalinity and sulfide inhibition in reactors, were discussed for a JLAFB and a general anaerobic fiuidized bed （AFB） reactor used as sulfate-reducing phase and methane-producing phase, respectively, in two-phase anaerobic digestion process. The formation of granules in the two reactors was also examined. The results indicated that COD and sulfate removal had different demand of influent COD/SO4^2- ratios. When total COD removal was up to 85%, the ratio was only required up to 1.2, whereas, total sulfate removal up to 95% required it exceeding 3.0. The alkalinity in the two reactors increased linearly with the growth of influent alkalinity. Moreover, the change of influent alkalinity had no significant effect on pH and volatile fatty acids （VFA） in the two reactors. Influent alkalinity kept at 400-500 mg/L could meet the requirement of the treating process. The JLAFB reactor had great advantage in avoiding sulfide and free-H2S accumulation and toxicity inhibition on microorganisms. When sulfate loading rate was up to 8. 1 kg/（m^3.d）, the sulfide and free-H2S concentrations in JLAFB reactor were 58.6 and 49.7 mg/L, respectively. Furthermore, the granules, with offwhite color, ellipse shape and diameters of 1.0-3.0 mm, could be developed in JLAFB reactor. In granules, different groups of bacteria were distributed in different layers, and some inorganic metal compounds such as Fe, Ca, Mg etc. were found.
文摘在"水解溶出+UASB反应器"处理城镇有机垃圾的两相厌氧系统中,向UASB反应器进水中添加K、Mg、Fe、Co、Ni 5种金属离子的组合促进剂,通过对UASB反应器容积负荷、产气量、产甲烷量在添加组合促进剂前后的比较,研究了组合促进剂(K、Mg、Fe、Co、Ni)对有机垃圾浸出液厌氧消化过程的促进作用。试验结果表明,添加组合促进剂后,反应器的平均容积负荷从12.89 kg COD/m3.d提高到17.79 kg COD/m3.d;平均污泥负荷从0.82 kg COD/kg VSS.d提高到1.07 kg COD/kg VSS.d。此外,平均每千克COD产气量为392.5 L,比添加组合促进剂之前增大了6.4%;而平均每千克COD产甲烷量为297.5 L,比添加组合促进剂之前增大了10.5%。对于氨氮、挥发性脂肪酸(VFA)、pH及碱度来说,在添加组合促进剂之后则无大的变化。
文摘以人工合成硫酸盐废水为基质,采用硫酸盐还原—气提脱硫—甲烷化的串联工艺,考察了硫酸盐还原相反应器和气提脱硫反应器的处理效果,并探讨了整个串联工艺系统的最佳工艺条件。结果表明:(1)硫酸盐还原相中SO42-负荷在回流比为15:1的情况下可达到10.5 kg SO42-/(m.3d),同时对SO42-的还原率保持在80%以上;(2)气提脱硫器效果显著,对硫化物的去除率在90%以上,出水硫化物含量<50 mg/L,不会对后续反应产生影响;(3)产甲烷相中COD负荷达到15kgCOD/(m.3d)时,去除率保持在85%以上;(4)进水废水pH在8.0左右时,反应器可获得最高的硫酸盐去除率并使出水中硫酸盐浓度在国家规定标准以下;(5)当COD/SO42-比值达到3时,系统对负荷的冲击仍有较强的耐受能力。整体工艺对SO42-的还原率达到90%以上,COD去除率在94%左右,该系统最终实现了硫酸盐及有机物有效去除的双重目标。
基金supported by the National Natural Science Foundation of China (Nos. 51178215 and 51378251)the Jiangsu Nature Science Fund (No. BK2011032)+2 种基金Open Science Foundation of Jiangsu (No. 50808121)the National Science and Technology Major Project for Water Pollution Control and Treatment (No. 2012ZX07301-005)the 2012 Scientific Research Open Found of Jiangsu Key Laboratory of Environmental Engineering
文摘A two-phase anaerobic reactor fed with glucose substrate（3 g chemical oxygen demand（COD）/L） was used to investigate the effects of toxic metals on the degradation of organics and the soluble microbial product（SMP） formation. Low concentrations of Ni（II）（5 and10 mg/L） promoted the acid phase, whereas high concentrations（15, 20, and 25 mg/L）exhibited an inhibitory effect on, but did not alter the fermentative method, which mainly involved the fermentation of propionic acid. The methanogenic microorganism exhibited a strong capability adapting constantly increased Ni（II） levels. The acid phase was an accumulation stage of SMP. In the absence of Ni（II）, the high-molecular-weight material in the effluent SMP mainly contained polysaccharide, tryptophan, and casein. Methanogens metabolized most of the polysaccharide, the whole tryptophan content, and part of the casein, leading to the presence of humic acid and protein in effluent. After Ni（II） dosage, the protein and polysaccharide of the acid phase increased, and tryptophan changed, while casein remained stable. More protein than polysaccharide was produced, suggesting the prominent function of protein when addressing the negative effect of toxic metals. The analysis of DNA confirmed the change of bacterial activity.
