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201.
中试厌氧氨氧化反应器的运行性能及其过程动力学特性 总被引:8,自引:3,他引:5
研究了上流式中试厌氧氨氧化(anaerobic ammonium oxidation,ANAMMOX)反应器在环境温度下的运行性能及其过程动力学特性.基质浓度试验表明,中试厌氧氨氧化反应器可在进水亚硝酸盐浓度为(380.4±18.3)mg.L-1稳定运行,继续提升至(480.5±21.9)mg.L-1时,反应器性能恶化.在水力停留时间(hydraulic retention time,HRT)试验中,HRT可缩短至3.43 h,反应器容积基质氮去除速率可达3.45 kg.(m3.d)-1.长期运行中,温度对中试厌氧氨氧化反应器的性能影响较大.采用改进型的Stover-Kincannon模型可较好地模拟非抑制状态下中试厌氧氨氧化反应器在不同温度范围下的行为.获得的Stover-Kincannon模型动力学参数及其出水总基质浓度预测公式和总基质去除率预测公式,可用于指导中试厌氧氨氧化反应器的实际操作. 相似文献
202.
203.
《安全.健康和环境》2007,7(5):48-49
小赵:分馏岗位外操1在有些人眼里,外操的技术含量较低,无非是挂个牌,采个样,打扫一下卫生,其实并不如此.我是由主操到外操岗位的,相比之下,外操并不比主操轻松多少.作为一名炼油操作工,特别是外操,一定要熟悉现场流程,用师傅的话说,就是"要知道每一根管线的走向,了解每一条流程的去向,这才是一个优秀的外操". 相似文献
204.
壳聚糖络合-超滤耦合过程去除溶液中铅离子的研究 总被引:3,自引:2,他引:1
采用聚醚砜超滤膜,以壳聚糖为络合剂络合-超滤去除溶液中Pb2+,考察了溶液pH值、Pb2+/壳聚糖装载量比、离子强度和Ca2+各因素对Pb2+截留率的影响,同时研究了超滤浓缩时间对Pb2+截留率及膜通量的影响.结果表明,溶液pH是决定络合-超滤耦合过程能否进行的关键因素;在pH为6.0, Pb2+/壳聚糖装载量比为0.25时,络合-超滤耦合过程对溶液中Pb2+的截留率达99%以上.溶液离子强度和Ca2+的增加均不利于络合-超滤耦合过程对Pb2+的去除.对浓缩的壳聚糖-铅溶液酸化解络之后,进一步采用全过滤过程回收壳聚糖.回收后的壳聚糖重新用于络合-超滤耦合过程去除溶液中Pb2+,此时对Pb2+的去除率为96.2%,与新鲜的壳聚糖没有明显差别.研究结果显示采用壳聚糖络合-超滤耦合过程能有效去除溶液中铅离子,同时实现壳聚糖的有效回收. 相似文献
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206.
This work was designed to explore the characteristics of photodegradation of herbicides in the copper-polluted water body. The
results showed that Cu(II) alone could induce a photo Fenton-like reaction to enhance the degradation of atrazine, in which hydroxyl
radical ( OH) was a main active species. Humic acids restrained atrazine degradation, nevertheless, when introducing Cu(II), the
photodegradation was accelerated, in which singlet oxygen (1O2) replaced OH acting as the prevailing species. A feasible mechanism
for the photochemical process was also proposed, which is helpful for better understanding the environmental photochemistry of
atrazine in the copper-polluted water. 相似文献
207.
Manuela Anzano Alessandra Tosti Marina Lasagni Alfredo Campiglio Demetrio Pite Elena Collina 《环境科学学报(英文版)》2011,23(9):1570-1577
The aim of the research was to develop new products and processes from a manufacturing waste from an Italian metallurgic company. The company produced thin silver metallic films and the production scraps were silver flakes. The possibility to use the silver flakes in water disinfection processes was studied. The antimicrobial activity of the flakes was investigated in batch using Escherichia coli as Gram-negative microorganism model. The flakes did not show any antimicrobial activity, so they were activated with two different processes: thermal activation in reducing atmosphere and chemical activation, obtaining, respectively, reduced flakes (RF) and chemical flakes (CF). The flakes, activated with either treatment, showed antimicrobial activity against E. coli. The kill rate was dependent on the type of activated flakes. The chemical flakes were more efficient than reduced flakes. The kill rate determined for 1 g of CF, 1.0 ± 0.2 min−1, was greater than the kill rate determined for 1 g of RF, 0.069 ± 0.004 min−1. This was confirmed also by the minimum inhibitory concentration values. It was demonstrated that the antimicrobial capability was dependent on flakes amount and on the type of aqueous medium. Furthermore, the flakes maintained their properties also when used a second time. Finally, the antimicrobial activities of flakes were tested in an effluent of a wastewater treatment plant where a variety of heterotrophic bacteria were present. 相似文献
208.
209.
工业生产过程中,由于工件热处理后,为改变其性能或提高效率,需要对热处理后的工件进行冷却。冷却方式常采用自然风冷、油浸冷却和水循环冷却。冷却系统在生产过程中,常因各车间液体循环系统压力不均衡,引起爆管现象,影响正常生产。 相似文献
210.
Pinpin Lu Xiaojian Zhang Chiqian Zhang Zhangbin Niu Shuguang Xie Chao Chen 《环境科学学报(英文版)》2014,26(2):323-331
This study investigated the bacterial regrowth in drinking water distribution systems receiving finished water from an advanced drinking water treatment plant in one city in southem China. Thirteen nodes in two water supply zones with different aged pipelines were selected to monitor water temperature, dissolved oxygen (DO), chloramine residual, assimilable organic carbon (AOC), and heterotrophic plate counts (HPC). Regression and principal component analyses indicated that HPC had a strong correlation with chloramine residual. Based on Chick-Watson's Law and the Monod equation, biostability curves under different conditions were developed to achieve the goal of HPC 100 CFU/mL. The biostability curves could interpret the scenario under various AOC concentrations and predict the required chloramine residual concentration under the condition of high AOC level. The simulation was also carded out to predict the scenario with a stricter HPC goal (≤50 CFU/mL) and determine the required chloramine residual. The biological regrowth control strategy was assessed using biostability curve analysis. The results indicated that maintaining high chloramine residual concentration was the most practical way to achieve the goal of HPC ≤ 100 CFU/mL. Biostability curves could be a very useful tool for biostability control in distribution systems. This work could provide some new insights towards biostability control in real distribution systems. 相似文献