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11.
污水处理系统处理效果的好坏都与污水处理系统中组成活性污泥的微生物种类、数量及其代谢活力有关,本文从活性污泥结构、微生物种类、数量及活性等方面分析了污泥生物相与运行状态的相互关系.说明了可通过对污水处理系统的生物相观察了解处理效果及运行状况,也可通过对污泥生物相观察发现处理系统环境的变化,及时调整运行环境,预防污水处理系统的运行中的异常情况发生.  相似文献   
12.
BACKGROUND: This study aimed to investigate the synthesis of zeolites from paper sludge ash (PSA) with added diatomite to remove both NH4+ and PO43? for water purification. The PSA had low Si and significant Ca contents. Four types of diatomite: white (T‐W) and brown (T‐B) from deposits of marine origin in Takanosu, and white (S‐W) and gray (S‐G) from lacustrine deposits in Shonai, were added to NaOH solution to increase the Si content and thereby synthesize zeolites with high cation exchange capacity (CEC). RESULTS: The order of the amounts of Si extracted from the diatomite to the alkali solution was S‐W > T‐W = T‐B > S‐G, which correlates with the amorphous SiO2 content of diatomite. The original ash without addition of diatomite yielded hydroxysodalite with CEC of about 1.0 mmol g?1. For all samples, the addition of diatomite to the solution yielded zeolite‐P with a higher CEC, but the addition of excess Si inhibited the synthesis of zeolite‐P, and the CEC of the product was low. A product with high CEC including zeolite‐P was obtained in a solution with around 500 mmol L?1 of Si concentration, and had the ability to remove both NH4+ and PO43?. CONCLUSION: Diatomite has the potential for used as an additive for the synthesis of high CEC zeolite from PSA. The product with zeolite‐P exhibited relatively high CEC, capacity for NH4+ uptake, and the ability to remove PO43? by precipitation, which is preferable for water purification applications. Copyright © 2008 Society of Chemical Industry  相似文献   
13.
Optimal control (OC) methodology is used to develop a control policy for a batch-operated solar sludge dryer with ventilation as the dominant control. Batch performance criteria and instantaneous optimization criteria are developed for two economic environments: quota limited and capital limited. The general formulation, as well as simplifications resulting from the multiplicative form of the evaporation (drying) rate model, are presented. The multiplicative form results in a single constant number, called here “control intensity,” which is used to guide the on-line control decisions. These decisions turn out to be independent of the dry solids content (DSC) of the sludge. Further simplification, by assuming a strictly constant weather, is used to demonstrate the general effects of the economic and physical (weather) environment on the solution.

The OC approach is used to address, via simulation under realistic weather conditions, several design, operation, and pricing problems. In particular, the following have been considered: sizing of the ventilation fans, determination of a fair fee for sludge disposal, finding the best final DSC, and evaluating the effect of the price of electricity. Regarding the particular location represented by the data, it has been shown that the installed capacity of the ventilation fans should be increased and that there seems to be sufficient economic incentive for solar drying.  相似文献   
14.
CAST的工作原理与设计计算   总被引:7,自引:0,他引:7  
详细论述了循环式活性污泥法(CAST)的工作原理,对该工艺的设计计算作了探讨,提出了设计方法,并提供了有关计算公式和操作时间分配。  相似文献   
15.
The anaerobic digestion of alkaline black liquor from a cereal straw pulping mill was studied in batch (serum bottles) and continuous systems (up-flow anaerobic sludge blanket reactor—UASB). The batch digestion studies confirmed that lignin and related compounds (LRC) in the alkaline black liquor were the main inhibitory substances and could not be decomposed by anaerobic bacteria. At organic loading rates of 5–10 kg COD m?3 day?1, the UASB reactor achieved 50–60% COD removal efficiencies. Gas production was 2–3 dm3 per dm3 of alkaline black liquor. Two different sludge types were examined in the reactor: granular and cluster-like sludges. Sludge in a cluster, which involved many small granules and flocs, tended to form larger aggregates and possessed good settling ability.  相似文献   
16.
剩余污泥中蛋白质的资源化利用是目前研究的热点,污泥预处理则是实现污泥中蛋白质释放的重要途径。为了进一步提高剩余污泥中蛋白质的溶出效果,选取热碱预处理、超声碱联合预处理、溶菌酶预处理对污泥进行溶胞,以蛋白质提取浓度为主要指标进行参数优化,并利用等电点法对粗提取蛋白进行纯化回收。结果表明:溶胞效果热碱预处理(pH值13、温度140℃、时间1.5 h,2 062.98 mg/L)>超声碱联合预处理(497.76 mg/L)>溶菌酶预处理(269.95 mg/L),且在pH值为3时热碱预处理蛋白质纯化回收率可达62.42%。试验结果表明:热碱预处理在提取效果方面较另外两种方法优势明显,具有良好的利用前景。  相似文献   
17.
Biosorption of heavy metal ions, such as Cu2+, Cd2+ and Zn2+, was carried out using waste activated sludge from municipal sewage treatment plant as adsorption material, and the effects of parameters, such as pH value, temperature, reaction time and sorption duration, were studied in detail. The results indicate that the removal rates of Cu2+, Zn2+ and Cd2+ with low concentration are 96.47%, 80% and 90%, respectively, adsorbed by waste activated sludge. Little effect of dosage of activated sludge on the adsorption of Cu2+ and more effects on the adsorption of Zn2+ and Cd2+ are observed. Little effect of temperature is observed, while pH value and adsorption time exert important influence on the sorption process. The adsorption behaviors of heavy metal ions all have parabolic relationships with pH value. The optimum pH value is between 6 and 10, and the optimum adsorption time is 1 h. In single heavy metal ion system, the sorption processes of Cu2+, Zn2+ and Cd2+ are in accordance with Freundlich model, which indicates that it is suitable for the treatment of these three heavy metal ions using intermittent operation. In addition, the sorption capacity of the sludge for Cu2+ is preferential to the other two ions.  相似文献   
18.
A/O结合循环式活性污泥法处理海产品加工废水   总被引:2,自引:0,他引:2  
针对海产品加工废水氨氮含量较高的特点。舟山兴业有限公司的污水处理工程采用两段A/O结合循环式活性污泥法工艺,工程验收合格后运行一年多来,排放废水的各项污染指标均达到国家《污水综合排放标准》(GB8978-1996)的二级标准,处理系统具有很好的抗冲击能力和脱氮效果。  相似文献   
19.
提高炼厂气综合利用水平的途径   总被引:1,自引:0,他引:1  
公司将进行催化裂化装置、气体分馏装置改造。预计改造后的丙烯产量将达到5.0万t/a,丁烯等C4产品大大增加。聚丙烯是公司目前丙烯化工利用的唯一产品,年产量2万t,C4的化工利用尚属空白。因此开辟过剩丙烯利用新途径,带动C4产业发展,形成化工产业链,提高公司炼厂气的综合利用水平,具有重要意义。合成异丙醇或环氧丙烷,就是这样一个突破口。  相似文献   
20.
UASB-SBR工艺处理城市生活污水的研究   总被引:4,自引:0,他引:4  
研究了UASB工艺处理城市生活污水的可行性,通过UASB与SBR组合工艺的运行实验,得出在水力停留时间3h时,COD去除率为61.67%-82.32%,出水COD达到国家污水排放二级标准。在氮磷去除效果不佳的情况下,采用SBR工艺处理后,其出水COD、SS、氮、磷等指标均达到国家污水一级排放标准。  相似文献   
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