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1.
郑明方 《江苏石油化工学院学报》2006,(3)
针对一类不允许出现超调的工艺参数,提出了采用动态BP网络对工艺参数进行控制,可以达到良好的效果。并以实验电炉为对象,用工控机对其炉温进行控制,结果表明,采用动态BP网络进行控制,可以无超调地无限逼近给定值,控制精度高,控制时间较短。因此可以认为,用动态BP网络对这一类工艺参数的控制是有效的。 相似文献
2.
讨论了邻苯二甲酸二丁酯(DBP)对聚醋酸乙烯酯(PVAcEm)胶膜的柔韧性、最低成膜温度(FMT)、黏度、粘接强度及稳定性的影响. 相似文献
3.
分别采用邻苯二甲酸二丁酯(DBP)和苯乙烯-丁二烯-苯乙烯(SBS)来增韧环氧树脂玻璃钢(EPFRP),探讨增韧剂对EP FRP的拉伸性能、冲击性能以及硬度的影响。结果表明:DBP和SBS的质量分数为7%左右时,经两种增韧剂改性的EP FRP的性能相当;而当质量分数大于7%时,DBP的增韧效果随用量的增大进一步增强,而SBS的增韧效果则呈减弱趋势。从断口的微观形貌来看,是由于DBP和SBS分散状况不同,导致了两者增韧机理和增韧效果的差异。 相似文献
4.
水中共存有机物会对纳滤产生影响,以邻苯二甲酸二丁酯(DBP)为对象,研究了NF90膜对纯水、模拟水和河水中DBP的去除效果。DBP的初始质量浓度为100μg/L。结果表明,NF90膜能实现对微量DBP的有效去除,截留率高达90%以上;在模拟水中,腐殖酸共存时,会引起膜通量的下降和截留率的上升,pH为7时,截留率最高,其他无机离子(K+、Ca2+)的加入,会减小膜通量增大截留率,其中,Ca2+的影响尤为明显;河水中的无机物和有机物成分复杂,膜通量会进一步减小,截留率进一步提高;纳滤初期,吸附会影响截留率,6 h后吸附达到饱和,稳定运行96 h后,膜污染会引起膜通量和截留率的下降。 相似文献
5.
Efficient removal of phthalate esters (PE) in wastewater treatment plants (WWTP) is becoming an increasing priority in many countries. In this study, we examined the fate of dimethyl phthalate (DMP), dibutyl phthalate (DBP), butylbenzyl phthalate (BBP), and di-(2-ethylhexyl) phthalate (DEHP) in a full scale activated sludge WWTP with biological removal of nitrogen and phosphorus. The mean concentrations of DMP, DBP, BBP, and DEHP at the WWTP inlet were 1.9, 20.5, 37.9, and 71.9 μg/L, respectively. Less than 0.1%, 42%, 35%, and 96% of DMP, DBP, BBP, and DEHP was associated with suspended solids, respectively. The overall microbial degradation of DMP, DBP, BBP, and DEHP in the WWTP was estimated to be 93%, 91%, 90%, and 81%, respectively. Seven to nine percent of the incoming PE were recovered in the WWTP effluent. Factors affecting microbial degradation of DEHP in activated sludge were studied using [U-14C-ring] DEHP as tracer. First order rate coefficients for aerobic DEHP degradation were 1.0×10−2, 1.4×10−2, and 1.3×10−3 at 20, 32, and 43 °C, respectively. Aerobic degradation rates decreased dramatically under aerobic thermophilic conditions (<0.1×10−2 h−1 at 60 °C). The degradation rate under anoxic denitrifying conditions was 0.3×10−2 h−1, whereas the rate under alternating conditions (aerobic-anoxic) was 0.8×10−2 h−1. Aerobic DEHP degradation in activated sludge samples was stimulated 5-9 times by addition of a phthalate degrading bacterium. The phthalate degrading bacterium was isolated from activated sludge, and maintained a capacity for DEHP degradation while growing on vegetable oil. Collectively, the results of the study identified several controls of microbial PE degradation in activated sludge. These controls may be considered to enhance PE degradation in activated sludge WWTP with biological removal of nitrogen and phosphorus. 相似文献
6.
Predicting disinfection by-product formation potential in water 总被引:5,自引:0,他引:5
Formation of regulated and non-regulated disinfection by-products (DBPs) is an issue at both potable water and wastewater treatment plants (W/WWTPs). Water samples from W/WWTPs across the USA were collected and DBP formation potentials (DBPFPs) in the presence of free chlorine and chloramine were obtained for trihalomethane (THM), haloacetic acid (HAA), haloacetonitrile (HAN), and N-nitrosodimethylamine (NDMA). With nearly 200 samples covering a range of dissolved organic carbon (0.6-23 mg/L), ultraviolet absorbance (0.01-0.48 cm−1 at 254 nm wavelength), and bromide (0-1.0 mg/L) levels, power function models were developed to predict the carbonaceous DBP (C-DBP) and nitrogenous DBP (N-DBP) precursors spanning 3 orders of magnitudes. The predicted THM and HAA formation potentials fitted well with the measured data (analytical variance of less than 22%). Inclusion of dissolved organic nitrogen (DON) into the HANFP model improved the predictions. NDMAFP was the most difficult one to predict based upon the selected water quality parameters, perhaps suggesting that bulk measurements such as DOC or UVA254 were not appropriate for tracking NDMAFP. These are the first such DBPFP models for wastewater systems, and among the few models that consider both C-DBPs and N-DBPs formation potentials from the same water sources. 相似文献
7.
利用低模数水玻璃,改变有关工艺参数,制取白碳黑产品,并探讨对产品二次结构及表面特性的影响. 相似文献
8.
The requirement for higher quality drinking water necessitates the application of more efficient water treatment techniques. Nanofiltration is one promising option for enhanced water treatment, for example, in enhanced organic matter removal. The characteristics of different nanofiltration membranes vary remarkably, and the selection of a membrane has to be made according to the requirements of an application. In this study six nanofiltration membranes (NF70, NF255, NTR-7450, NTR-7410, Desal-5 and TFC-S) were evaluated in improving the quality of chemically pre-treated surface water in a pilot-scale process. The results indicate that the membrane with high organics removal and slightly reduced ion removal characteristics (NF255) performed best in terms of product water quality as well as membrane productivity and fouling. The most permeable membrane (NTR-7410) suffered intensive fouling and insufficient product water quality. An interesting finding was that the permeates of all the tested membranes possessed a significant potential for microbial growth, despite the low nutrient contents. 相似文献
9.
通过等温吸附试验,研究了超高交联树脂NDA-66对邻苯二甲酸(ο-PA)的吸附性能及吸附行为,同时优化了NDA-66处理增塑剂DBP生产废水吸附-脱附工艺参数。经过初步筛选发现,NDA-66树脂对ο-PA具有良好的吸附性能,在温度为15℃、30℃和45℃条件下分别测定了吸附平衡数据,ο-PA在NDA-66树脂上的吸附平衡符合Freundlich等温吸附方程,温度对吸附的影响较大。参数优化试验结果表明:树脂吸附最佳工艺参数是:pH 2.0~2.4,温度30℃,流速为1.5 BV/h;树脂脱附最佳工艺参数,脱附剂用量及组成为1 BV 8%NaOH+2 BV H_2O,脱附温度为55℃,脱附流速为1.5 BV/h。 相似文献
10.
The feasibility of electrochemical hydrodehalogenation (HDH) of 2,4-dibromophenol (DBP) in paraffin oil has been evaluated for short or long operation periods of up to 170 h. HDH has been performed successfully using a solid polymer electrolyte reactor in a batch recycle mode with a dilute H2SO4 aqueous solution as the anode feed and source of protons. The work reported in this paper expands the application of electrochemical HDH from aqueous systems to non-conductive media. The effect of the operating conditions, including current density, reactant concentration and temperature, is evaluated. The results are compared with those achieved in the aqueous solutions. 相似文献