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791.
磷作为一种重要的元素而被广泛应用于农业与工业中,然而磷的过量排放已成为许多封闭半封闭水体富营养化和沿海赤潮频繁发生的原因之一.去除水体中的营养盐特别是磷酸盐,是有效控制水体富营养化的关键.广州市某河涌水含总磷2.6 mg/L,采用并选择DS离子交换树脂对水中磷进行动态吸附和去除,可使水中的磷降至排放标准以内,解决河涌水含磷高的富营养化问题.由DS树脂所吸附的磷,通过淋洗可得到含磷富集液,使磷从水体中完全分离出来并获得回收.DS树脂的再生能力强,经6次吸附-解吸-再生后,树脂对河涌水中磷的去除率仍可达到90%以上. 相似文献
792.
采用两级氧化法处理油田压裂返排液。在次氯酸钠、次氯酸钙、过氧化氢、高锰酸钾4种氧化剂中,次氯酸钠的氧化效果最好。以次氯酸钠作为一级氧化剂,进行一级氧化处理;再分别采用次氯酸钙、过氧化氢、高锰酸钾进行二级氧化处理。在次氯酸钠加入量为40mL/L、一级氧化反应时间为30min、二级氧化反应时间为30min、初始废水COD为3976mg/L的条件下,二级氧化剂过氧化氢、次氯酸钙、高锰酸钾的最佳加入量分别为80,40,40mL/L,对应的COD去除率分别为82.60%,71.50%,83.50%。 相似文献
793.
794.
采用自制的负载型CuO-ZnO-CeO2/γ-Al2O3催化剂,常温常压下通过紫外辐照-催化湿式氧化技术处理酸性大红GR模拟染料废水。考察了催化剂加入量、H2O2加入量、废水pH、反应时间、初始酸性大红GR质量浓度等对废水脱色率的影响。实验得到最佳工艺条件为初始酸性大红GR质量浓度200mg/L,催化剂加入量10.0g/L,H2O2加入量2.0mL/L,废水pH4,反应时间2h。最佳工艺条件下废水脱色率达99.33%。 相似文献
795.
以堇青石蜂窝陶瓷(CC)为载体,采用浸渍法制备了堇青石负载Pd和过渡金属混合氧化物催化剂,记作Pd-M-Mn(M=Cu,Co,Fe,Ni)/CC。实验结果表明:Pd-Co-Mn/CC催化剂的催化活性最高;随着Pd负载量的增加,CO转化率提高;当Pd负载量为1.00%时,反应温度为150℃时CO转化率达到98%,200℃时CO转化率达到100%;在反应温度150℃条件下,Pd-Co-Mn/CC催化剂(Pd负载量1.00%)的CO转化率在前30h内小幅度下降,随后稳定在90%以上,反应100h后,催化剂表面颜色由黑色变为棕褐色。 相似文献
796.
797.
Xiao Wu Jun Zhu Curtis Miller 《Journal of environmental science and health. Part. B》2013,48(6):477-485
Kinetics of H2 production from liquid swine manure supplemented with glucose by mixed anaerobic cultures was investigated using batch experiments under four different pH conditions (4.4, 5.0, 5.6, and uncontrolled). The temperature for the experiments was controlled at 37 ± 1°C and the length of experiments varied between 50 and 120 hours, depending upon the time needed for completion of each individual experiment. The modified Gompertz model was evaluated for its suitability for describing the H2 production potential, H2 production rate, and substrate consumption rate for all the experiments. The results showed that the Gompertz model could adequately fit the experimental results. The effect of pH was significant on all kinetic parameters for H2 production including yield, production rate and lag time, and the substrate utilization rate. The optimal pH was found to be 5.0, at which a maximum H2 production rate (0.64 L H2/h) was obtained, and deviation from the optimal pH could result in substantial reductions in H2 production rate (0.32 L H2/h for pH 4.0 and 0.43 L H2/h for pH 5.6). The results also showed that if pH was not controlled for the batch fermentation process, the substrate utilization efficiency could steeply decrease from 98.8% to 33.7%. 相似文献
798.
Changpeng Zhang Hua Zhao Lifeng Ping Xiaoming Cai Min Wu Hongmei He 《Journal of environmental science and health. Part. B》2013,48(5):319-323
This study investigated the degradation of rizazole in water-sediment systems (West Lake system, WL; Beijing–Hangzhou Grand Canal system, BG) with two different types of sediments under aerobic and anaerobic conditions. The half-lives of rizazole in the WL water phase (14.59–15.13 d) were similar to those in the BG water phase (15.90–16.46 d). Within 3–7 d, the rizazole concentration in the sediments reached the maximum values, i.e., equilibrium. Rizazole dissipation was faster in the WL sediment phase with higher organic matter content (T1/2 = 18.99–19.09 d) compared with the BG sediment phase (T1/2 = 31.08–33.32 d). Rizazole degradation was slightly faster in the West Lake water-sediment system (WL system) (T1/2 = 17.11–18.05 d) than in the Beijing–Hangzhou Grand Canal water—sediment system (BG system) (T1/2 = 20.51–25.02 d). The aerobic degradation of rizazole was similar to its anaerobic degradation in the water-sediment system. The findings are useful to understand the behavior of pesticide in environment. 相似文献
799.
800.
Ji-Feng Yang Shi-Biao Zhou An-Guo Xiao Wen-Jun Li Guang-Guo Ying 《Journal of environmental science and health. Part. B》2013,48(12):909-916
This paper investigated sulfadiazine oxidation by the Fenton process under various reaction conditions. The reaction conditions tested in the experiments included the initial pH value of reaction solutions, and the dosages of ferrous ions and hydrogen peroxide. Under the reaction conditions with pH 3, 0.25 mM of ferrous ion and 2 mM of hydrogen peroxide, a removal efficiency of nearly 100% was achieved for sulfadiazine. A series of intermediate products including 4-OH-sulfadiazine/or 5-OH-sulfadiazine, 2-aminopyrimidine, sulfanilamide, formic acid, and oxalic acid were identified. Based on these products, the possible oxidation pathway of sulfadiazine by Fenton's reagent was proposed. The toxicity evaluation of reaction solutions showed increased antimicrobial effects following the Fenton oxidation process. The results from this study suggest that the Fenton oxidation process could remove sulfadiazine, but also increase solution toxicity due to the presence of more toxic products. 相似文献