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991.
采用响应面分析法对聚合氯化铝(PAC)与污泥生产的微生物絮凝剂复配处理涂料废水的过程进行了优化,设定的响应值为COD和色度去除率。实验分别拟合了关于COD去除率和色度去除率的二次模型,根据响应值的分布情况,确定涂料废水的最佳絮凝条件为微生物絮凝剂浓度47 mg/L,PAC浓度39 mg/L,pH为8.2,CaCl2浓度0.38 g/L,搅拌速度210 r/min。最佳絮凝条件下,微生物絮凝剂对涂料废水中COD和色度的去除率分别达到77.6%和68.9%。 相似文献
992.
Ming T. Li Jin H. Liu Shu J. Zhao Zhang X. Wang Lin L. Hao 《Journal of environmental science and health. Part. B》2013,48(10):885-892
A psychrotolerant denitrifying bacterial strain, DBP-3, was isolated from a eutrophic body of water by low-temperature-oriented acclimation culture. Based on its morphologicalandbiochemicalcharacteristics and 16S rDNA gene sequence, the bacterium was identified as belonging to the genus Acinetobacter and closely related to A. johnonii. The satisfactory growth of DBP-3 was observed at 10–30°C and pH 7–9. Strain DBP-3 was able to utilize three types of carbon sources (sodium acetate > sodium citrate > glucose) to support growth and denitrification. DBP-3 grew faster, but with lower nitrate removal efficiency and higher nitrite accumulation, under aerobic conditions than under anoxic conditions. DBP-3 was extremely susceptible to tetracycline and rifampicine and less sensitive to ampicillin and penicillin. The growth of DBP-3 was significantly affected by Hg (II), Cr (VI), Pb (II), Cd (II), and As (III) at 0.32, 0.63, 1.25, 2.5, and 25.0 mg L?1, respectively. Interestingly, chromium (VI) significantly promoted DBP-3 growth at concentrations lower than 0.32 mg L?1. These data may be helpful to support the use of strain DBP-3 in the purification of eutrophic water bodies at low temperatures. 相似文献
993.
HungMin Chein Tzu Ming Chen Shankar Gopala Aggarwal Chuen-Jinn Tsai Chun-Chao Huang 《Journal of the Air & Waste Management Association (1995)》2013,63(2):218-228
Abstract A huge amount of inorganic acids can be produced and emitted with waste gases from integrated circuit manufacturing processes such as cleaning and etching. Emission of inorganic acids from selected semiconductor factories was measured in this study. The sampling of the inorganic acids was based on the porous metal denuders, and samples were then analyzed by ion chromatography. The amount of chemical usage was adopted from the data that were reported to the Environmental Protection Bureau in Hsin-chu County according to the Taiwan Environmental Protection Agency regulation. The emission factor is defined as the emission rate (kg/month) divided by the amount of chemical usage (L/month). Emission factors of three inorganic acids (i.e., hydrofluoric acid [HF], hydrochloric acid [HQ], and sulfuric acid [H2SO4]) were estimated by the same method. The emission factors of HF and HCl were determined to be 0.0075 kg/L (coefficient of variation [CV] = 60.7%, n = 80) and 0.0096 kg/L (CV = 68.2%, n = 91), respectively. Linear regression equations are proposed to fit the data with correlation coefficient square (R2) = 0.82 and 0.9, respectively. The emission factor of H2SO4, which is in the droplet form, was determined to be 0.0016 kg/L (CV = 99.2%, n = 107), and its R2 was 0.84. The emission profiles of gaseous inorganic acids show that HF is the dominant chemical in most of the fabricators. 相似文献
994.
Chia Hao Hsu Chorng Ming Cho 《Journal of the Air & Waste Management Association (1995)》2013,63(2):246-252
Abstract The removal system for the absorption of CO2 with amines and NH3 is an advanced air pollution control device to reduce greenhouse gas emissions. Absorption of CO2 by amines and NH3 solutions was performed in this study to derive the reaction kinetics. The absorption of CO2 as encountered in flue gases into aqueous solutions of monoethanolamine (MEA), diethanolamine (DEA), and NH3 was carried out using a stirred vessel with a plane gas-liquid interface at 50 °C. Various operating parameters were tested to determine the effect of these variables on the absorption kinetics of the reactants in both gas and liquid phases and the effect of competitions between various reactants on the mass-transfer rate. The observed absorption rate increases with increasing gas-liquid concentration, solvent concentration, temperature, and gas flow rate, but changes with the O2 concentration and pH value. The absorption efficiency of MEA is better than that of NH3 and DEA, but the absorption capacity of NH3 is the best. The active energies of the MEA and NH3 with CO2 are 33.19 and 40.09 kJ/mol, respectively. 相似文献
995.
实施污染物总量减排是我国环境管理和污染控制的重大举措,“十二五”期间仍将是我国环境保护的重点内容。本文根据四川省“十一五”总量减排的成效和问题,结合国家对“十二五”总量减排的新要求和特点,从畜禽养殖、城镇生活污染、机动车尾气防治、重点行业减排等方面,对未来减排存在的压力进行了分析,并由此提出了优化产业结构、严把项目准入关、加强环保基础设施建设和管理、加强机动车污染防治、加强畜禽污染治理、加强重点污染源治理、构建综合保障体系等措施和建议。 相似文献
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