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991.
对TA高效降解菌株的生长培养基进行了5因素2水平标准的正交设计,考察了碳源(精对苯二甲酸PTA)、氮源(NH4Cl)、磷源(K2HPO4)、生长因子(MgSO4、FeSO4、CaCl2的混合物)和酵母膏对菌体生长的影响。并与肉汤培养基相对照,得到TA高效降解菌株生长培养基为:PTA10g/L;NH4Cl 0.5g/L;K2HPO4 0.1g/L;生长因子(MgSO4 0.1g/L,FeSO4 0.01g/L,CaCl2 0.01g/L的混合物);Y.E2.5g/L。 相似文献
992.
993.
针对零星居民点的污水处理,开发了射流曝气周期活性污泥法工艺.它是一种连续进水、周期性间歇曝气的改良型SBR工艺,也是一种时间程序和空间程序相结合的污水处理工艺,具有良好的脱氮除磷效果.试验表明,在水力负荷4 m3/d,曝气周期为每2 h曝气15 min、静置105 min的条件下,出水COD为48.8~53.5 mg/L,去除率达79.4%~80.5%;出水TN为2.81~3.98 mg/L,去除率达82.4%~89.4%;出水NH3-N为0.36~0.78 mg/L,去除率高达96.4%~98.4%;出水TP为0.63~1.18 mg/L,去除率为67.2%~78.9%,均可达到《城镇污水处理厂污染物排放标准》(GB 18918-2002)中的一级B排放标准. 相似文献
994.
污泥是城市污水处理厂的副产物,若处理不当,将会带来一系列严重的环境问题.实验采用低强度超声波对剩余活性污泥(WAS)的好氧消化过程进行强化,选取超声强度、超声时间、超声间隔3个因素设计正交实验.结果表明,经超声辐照的WAS,其好氧消化时间最短仅约为13 d,比未经超声辐照的缩短了18.00 d.对实验结果的极差分析和方差分析表明,低强度超声波强化WAS好氧消化的最佳参数为:超声强度1.0 W/cm2、超声时间10 min、超声间隔8 h.实验还研究了WAS达标前后溶解性化学需氧量(SCOD)和总化学需氧量(TCOD)的变化情况,发现在相对较短的处理时间内,经低强度超声波强化处理的WAS的TCOD降解率仍然能与对照相近甚至高于对照,主要原因是低强度超声波强化了微生物的新陈代谢,促进了其对有机物的吸收分解. 相似文献
995.
城市污水处理厂除臭技术 总被引:10,自引:0,他引:10
介绍了城市污水处理厂臭气来源、成分及产量。针对目前国内外除臭技术的研究和发展情况,分析了污水处理厂的各种物理、化学和生物除臭方法的技术原理、优缺点和应用现状。结合日本城市污水处理厂的运行实际,重点介绍了一种不产生臭气的新技术——腐殖活性污泥法的工艺流程、特点及其应用现状。 相似文献
996.
Leaching of bisphenol A (BPA) to seawater from polycarbonate plastic and its degradation by reactive oxygen species 总被引:4,自引:0,他引:4
In this study, (1) change in the concentration of bisphenol A (BPA) leached from polycarbonate (PC) tube to control water (BPA free), seawater and river water at 20 and 37 degrees C as a function of time, (2) the fate of BPA caused by addition of H(2)O(2) and Fe(3+) to seawater containing BPA leached from PC tube were assessed. BPA leached from PC tube to all water samples increased with the ascendant of temperature and with the passage of time. The BPA leaching velocity in seawater was the fastest in three samples (11 ng/day for seawater, 4.8 ng/day for river water 0.8 ng/day for control water at 37 degrees C).BPA leaching velocity from PC tube was significantly high at pH 8 (50 mM Na(2)HPO(4)) and increased dose-dependently. There was no difference in the velocity of BPA among the 50 mM phosphate-buffers at pH 6.5, 7.0 and 7.5. BPA was leached three times higher by addition of Na(+) than K(+). However, the higher the K(+) concentration, the larger the BPA leached from PC tube. Na(+) mixed with PO(4)(-) was effective on BPA leaching from PC tube, but not with SO(4)(-) or Cl(-). The results suggested that BPA leaching from PC tube would be attributed to the concentration of bibasic phosphate such as Na(2)HPO(4) and K(2)HPO(4) in water samples. BPA was degraded in both control water and seawater in the presence of radical oxygen species, but the degradation rate was lower in seawater than in control water, suggesting that anti-oxidative system exists in seawater. Neo-synthesized substance in both control water and seawater in the presence of reactive oxygen species was identified as BPA-quinone by LC-MS. 相似文献
997.
超声波强化污水厌氧生物处理综述 总被引:1,自引:0,他引:1
通过对超声波辐射促进微生物活性以及超声波强化污水好氧生物处理、厌氧污泥减量化处理等作用机制的分析研究,探讨将超声波应用于强化污水厌氧生物处理的可行性.同时对超声波强化污水厌氧生物处理的应用前景进行了展望. 相似文献
998.
Aqueous solubilities of four non-ortho and eight mono-ortho substituted PCBs were determined using a generator-column technique followed by subsequent off-line GC/ECD analysis of the aqueous solutions. The method is based on pumping water through a column containing glass beads coated with the congener being studied and has been used to measure solubilities at room temperature. The method circumvents many of the experimental difficulties encountered with the traditional shake-flask system. Aqueous solubility of 3,3′,4,4′-tetrachlorobiphenyl determined by this procedure is compared with data obtained from the shake-flask method and the computational method. The precision of replicate measurements is better than ±6.5%. Aqueous solubilities determined for 12 congeners ranged from 6.07 × 10−11 to 4.47 × −9 mol/L and generally decreased with molecular weight and increased with degree of ortho-chlorine substitution within a molecular-weight class. 相似文献
999.
1000.
Short-term experiments were conducted to investigate the effect of a commercial Fe and an iron-bearing clay mineral, ferruginuous smectite (SWa-1), on the degradation of pentachloroethane (PCA). After 3 h of contact time, SWa-1 catalyzed PCA dehydrochlorination to tetrachloroethene (PCE, 65% conversion), whereas commercial Fe promoted PCA stepwise dechlorination via dehydrochlorination (approximately 40% conversion) and subsequent PCE hydrogenolysis to trichloroethene (TCE). The addition of unaltered SWa-1 to commercial Fe led to a complete inhibition on TCE production, whereas the addition of reduced SWa-1 barely resulted in a 30% decrease. 相似文献