膜生物反应器处理印染废水技术研究

采用小试规模(148L/d)的厌氧-好氧膜生物反应器处理印染废水.当水力停留时间为14小时,进水COD、色度分别为208.54～2592.00mg/l、32～256倍,通过水解酸化-体式膜生物反应器试验,系统对COD、色度的去除率分别达到了80%～90%、87.5%.出水水质浓度或指标分别为21.80～363.20mg/l、8倍,具有良好的处理效果.厌氧-好氧膜生物反应器工艺处理印染废水技术可行、操作简单、易于管理、可为工业规模应用提供技术参考.     

高级氧化技术强化皮革废水生化处理效果初探

皮革废水中含大量难降解有机物,导致常规好氧生化处理速率低、效果差.实验考察了在Us(超声波)、UV(紫外光)、US/Fenton、UV/Fenton等高级氧化技术强化作用下的生化处理效果,结果表明,在相同水质和实验条件下,废水经Us、UV处理30min后可使后续生化反应速率显著提高,分别反应8h、24h后的COD去除率即可达到直接经微生物处理48h后达到的48%,但延长反应时间至48h对COD去除率没有明显提高;Fenton试剂强化US、UV的处理效果要高于单独Us、UV工艺,经30min预处理,随后在微生物作用下分别反应4h和8h即可达到45%和51%的COD去除率,同时延长反应时间也能使最终COD去除率明显提高,反应48h后,COD去除率可分别提高至64%和72%.     

Characterization of sulfide oxidation and optimization of sulfate production by a thermophilic Paenibacillus naphthalenovorans LYH-3 isolated from sewage sludge composting

The sulfur-containing odor emitted from sludge composting could be controlled by sulfide oxidizing bacteria, yet mesophilic strains show inactivation during the thermophilic stage of composting. Aimed to investigate and characterize the thermotolerant bacterium that could oxidize sulfide into sulfate, a heterotrophic strain was isolated from sewage sludge composting and identified as Paenibacillus naphthalenovorans LYH-3. The effects of various environmental factors on sulfide oxidation capacities were studied to optimize the sulfate production, and the highest production rate (27.35% ± 0.86%) was obtained at pH 7.34, the rotation speed of 161.14 r/min, and the inoculation amount of 5.83% by employing Box-Behnken design. The results of serial sulfide substrates experiments indicated that strain LYH-3 could survive up to 400 mg/L of sulfide with the highest sulfide removal rate (88.79% ± 0.35%) obtained at 50 mg/L of sulfide. Growth kinetic analysis presented the maximum specific growth rate µ_m (0.5274 hr⁻¹) after 22 hr cultivation at 50°C. The highest enzyme activities of sulfide quinone oxidoreductase (0.369 ± 0.052 U/mg) and sulfur dioxygenase (0.255 ± 0.014 U/mg) were both obtained at 40°C, and the highest enzyme activity of sulfite acceptor oxidoreductase (1.302 ± 0.035 U/mg) was assessed at 50°C. The results indicated that P. naphthalenovorans possessed a rapid growth rate and efficient sulfide oxidation capacities under thermophilic conditions, promising a potential application in controlling sulfur-containing odors during the thermophilic stage of sludge composting.     

木质素降解酶及其调控机理研究的进展

近年来有关木质素降解微生物和木质素降解酶的产与调控机理的研究表明，腐霉和细菌在木质自然降解中起着重要作用，腐霉的降解作用发生在次级代谢阶段，而细菌发生在初级代谢阶段，影响木质素降解酶的产生酶活力高低的因素有碳氮的选择与限制；诱导物的添加；表面活性剂的使用；某些金属离子浓度水平的改变；菌丝的固定化，温度和摇床转速的变换等。     

超深厌氧塘的技术特性

超深厌氧塘是一种稳定塘新工艺。与常规厌氧塘相比，具有ＢＯＤ５容积负荷大、占地面积小，受温度影响小的优点。探讨了它的工作机理，本研究确定了负荷、水深和去除率之间的定量关系以供实际应用。     

厌氧--好氧--硅藻土处理屠宰废水工程实例

采用厌氧—好氧—硅藻土法处理屠宰废水 ,经过一段时间运行表明 ,处理效果稳定 ,进水CODcrll0 0 0mg/L左右 ,出水在 12 0mg/L以下。本文总结了设计施工过程中一些经验教训     

Population growth, management and environmental degradation in China

Environmental problems in China can be divided into two large classes: pollution and destruction of natural environment. Environmental degradation is particularly serious in areas with rapid population growth. In this paper, some of China's major environmental problems, particularly those concerned with land, forests, and continental waters are introduced in order to see how population growth and management have affected these resources over the past few decades. It is also explained how the Chinese plan to cope and eventually solve these problems.     

ABR工艺预处理木薯酒糟废水的工程应用

木薯酒糟废水有机物浓度高、悬浮物含量大、pH呈酸性、可生化性能较差 ,通常直接采用固液分离—厌氧 (UASB)—好氧曝气生化法处理效果并不理想 ,而采用ABR工艺进行厌氧水解酸化预处理木薯酒糟废水迄今为止未见报道。经绵阳市酒厂废水治理工程证明 ,强化ABR预处理工序是保证后续处理措施能否正常运行的关键     

Degradation of Populus euphratica community in the lower reaches of the Tarim River, Xinjiang, China

IntroductionRiparian systems are aquatic-terrestrial ecotones withunique biotic , biophysical and landscape characteristics(Gregory, 1991 ; Naiman, 1997 ; Wiens , 2002) and areshaped by fluvial geomorphic processes . Riparian plantcommunities perform an i…     

镉胁迫下大豆中镉的分布状况及其籽粒品质

溶液培养中0.5μmol·L-1镉胁迫浓度下,大豆表现出轻微受害症状,籽粒减产25 . 7%,而籽粒中粗脂肪和粗蛋白含量变化不大.镉在大豆中的积累分布状况为根>叶>籽>油,比例为32.100:1.690:1.000:0.003.大豆籽粒含镉4.89mg/kg,超过了国家环境标准规定的最高容许量.而大豆粗脂肪中含镉仅0.015mg/kg,远低于国家食品环境卫生标准.豆粕中含镉6.17mg/kg,表明大豆籽粒中的镉主要存在于粗蛋白和淀粉中.