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811.
介绍采用气浮-水解-接触氧化工艺处理蜡防印花废水技术。工程实践运行表明,该工艺处理效果好、运行稳定。各项指标均可达到《纺织染整工业水污染物排放标准》(GB4287-1992)二级排放标准。 相似文献
812.
813.
开发中小城镇适用的简易高效污水处理成套技术,解决城镇污水处理厂的三高问题,这对于污染严重、资源短缺、经济尚不够发达的我国,在一段时期内具有重要意义。在城市污水处理厂建立了改进型膨胀颗粒污泥床(EGSB)+接触氧化组合中试工艺处理城市污水,在组合工艺停留时间为8h时,出水COD、氨氮、SS都能够达到城市污水二级排放标准。水力停留时间对组合工艺出水中的氨氮、SS去除效果影响明显,随着水力停留时间的提高,出水中的氨氮、SS下降。当处理量为1000t/d时,对该组合工艺的能耗进行了计算,吨水能耗为0.13元,为传统城镇污水处理吨水能耗的55%左右。 相似文献
814.
The possibility of implementing 12 principles of the ecosystem approach is considered with regard to the results of meetings of the Conference of the Parties to the Convention on Biological Diversity (CBD) and recent international forums. The importance of these principles for achieving the main goals of the CBD is shown, and the role of biosphere reserves in solving urgent problems of biodiversity conservation and sustainable development in adjoining territories of subjects of the Russian Federation is discussed. 相似文献
815.
Background, aim, and scope The pulp and paper industry is the sixth largest polluter discharging a variety of gaseous, liquid, and solid wastes into
the environment. Effluents from bleached Kraft mill effluents (BKME) are polluting waters to a great extent These effluents
cause considerable damage to the receiving waters if discharged untreated since they have high levels of biological oxygen
demand (BOD), chemical oxygen demand (COD), chlorinated compounds (measured as AOX), suspended solids (mainly fibers), fatty
acids, tannins, resin acids, lignin and its derivatives, sulfur and sulfur compounds, etc. This study aimed to remove adsorbed
organic halogen (AOX), total nitrogen, and lignin-degrading products in the wastewater (4,500 m3/h) from the paper mill in the pulp and paper industry, which is discharged to sea from a plant located in western Turkey.
Materials and methods The photocatalytic degradation of AOX, total nitrogen, and chlorinated lignin in BKME have been investigated in different
parameters, such as time, H2O2 and TiO2 concentration. In addition, for investigating the effect of chlorine on the removal of lignin, pure lignin solution was prepared
in equal amounts to chlorinated lignin degradation products found in BKME. The same experiments were conducted for this solution.
Experiments were carried out in photocatalytic reactor made of Pyrex glass. The mercury lamp was used as a radiation source.
All irradiation was carried out under constant stirring. The existence of dissolved O2 is an important factor which increases the photocatalytic degradation. Hence, we used an air pump for the aeration of the
wastewater solutions. The temperature of the wastewater was controlled and adjusted to 25°C by thermostat pump in conjunction
with a cooler. At the end of all experiments, AOX, total nitrogen and lignin concentrations were analyzed according to standard
methods. All experiments were performed in duplicate and average values were used.
Results and discussion When the effect of H2O2 and time were investigated, it was observed that the AOX concentration increased from 3.0 to 11.0 mg/L by only UV. However,
when H2O2 was added, AOX concentration decreased from approximately 3.0 to 0.0 mg/L. The optimal conditions for the removal of AOX
appear to be an initial H2O2 concentration of 20.0 mL/L and reaction time of 50 min. In addition, at the same experiment conditions, it was seen that
the total nitrogen concentration decreased from 23.0 to 15.0 mg/L by only UV and by increasing H2O2 concentration, the concentration of 20.0 mL/L H2O2 appears to be optimal (9.0 mg/L). The AOX, total nitrogen and lignin degradation products and pure lignin go through a minimum
when the concentration of H2O2 and TiO2 increases at constant pH and UV intensity. The kinetics for the degradation of AOX, total nitrogen and lignin degradation
products followed a pseudo-first order law with respect to the products, and the degradation rates (min−1) for the UV/TiO2/H2O2 system were higher than that of the corresponding values for the UV/H2O2 system.
Conclusions The AOX, total nitrogen and lignin concentration go through a minimum when the concentration of H2O2 and TiO2 increases at constant pH and UV intensity. It was found that the UV/TiO2/H2O2 system has proved capable of the degradation of total nitrogen as well as chlorinated and degraded lignin in BKME.
Recommendations and perspectives The photocatalytic process can be considered a suitable alternative for the remove of some compounds from the BKME. Nevertheless,
further studies should be carried out to confirm the practical feasibility of BKME. Another result obtained from the study
is that pre-purification carried out with UV/TiO2/H2O2 photocatalytic process may constitute an important step for further purification processes such as adsorption, membrane processes,
etc. 相似文献
816.
817.
混凝-催化氧化-水解酸化-生物接触氧化法处理染料废水的中试研究 总被引:2,自引:0,他引:2
采用混凝-催化氧化-水解酸化-生物接触氧化法处理高浓度难降解分散染料废水.比较分析了O_3、UV/TiO_2/O_3,UV/O_3/H_2O_23种高级氧化法的处理效果.结果表明,UV/TiO_2/O_3对废水COD和色度有较高的去除率.可明显改善废水的可生化性,废水的BOD_5/COD由0.05~0.07升高至0.42~0.46.在混凝沉淀单元HRT为1.5 h.催化氧化单元(UV/TiO_2/O_3)HRT为3.0 h,水解酸化HRT为10.0 h,生物接触氧化HRT为10.0 h的最佳条件下,该组合工艺对废水COD和色度总的去除率分别可达95.0%、99.5%. 相似文献
818.
819.
820.
江苏省某企业中药污水处理工程采用调节池+深度水解+三级接触氧化+沉淀的处理工艺,该工艺运行费用低,处理效果稳定,便于管理,操作简单,易于维护。运行过程中,进水COD为2 500~3 500 mg/L,BOD5为1 200~1 500 mg/L,其出水各项指标均达到《污水综合排放标准》(GB 8978-1996)中的一级排放标准。 相似文献