陶瓷电镀废水的三级处理工艺

以色度、浊度、悬浮物浓度、电导率及金属离子浓度为检测指标,研究进水pH、混凝剂种类与投量、沉降时间及重金属捕捉剂对陶瓷电镀废水的处理效果,探讨陶瓷电镀废水处理的适宜操作条件及工艺组合。实验表明,陶瓷电镀废水的组合处理工艺:调整废水pH为一级处理,投加PAC的混凝沉降法为二级处理,投加重金属捕捉剂为三级处理;先调节废水pH至9,投加50 mg/L的PAC,再投加20 mg/L重金属捕捉剂,此时废水的色度降至10倍,浊度降至16 NTU,悬浮物浓度降至210 mg/L去除率达到95.1%,各金属离子浓度也明显降低,处理出水的悬浮物达到《污水综合排放标准》(GB8978-1996)的三级标准,其他各指标均达到《电镀污染物排放标准》(GB21900-2008)。     

全国有色标准委修订金属废料国家标准

2005年12月11日，全国有色金属标准化技术委员会在北京召开了“再生有色金属标准化工作会议”，全国50多家重点再生企业参加了此次会议。会上，代表们认真论证了由北京中色再生金属研究所修订的关于GB／T13586（（铝及铝合金废料》、GB／T13587（（铜及铜合金废料》、GB／T13588（铅及铅合金废料》三个国家标准，并一致同意通过。     

Using a biological aerated filter to treat mixed water-borne volatile organic compounds and assessing its emissions

A biological aerated filter (BAF) was evaluated as a fixed-biofilm process to remove water-borne volatile organic compounds (VOCs) from a multiple layer ceramic capacitor (MLCC) manufacturing plant in southern Taiwan. The components of VOC were identified to be toluene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, bromodichloromethane and isopropanol (IPA). The full-scale BAF was constructed of two separate reactors in series, respectively, using 10- and 15-cm diameter polypropylene balls as the packing materials and a successful preliminary bench-scale experiment was performed to feasibility. Experimental results show that the BAF removed over 90% chemical oxygen demand (COD) from the influent with (1188 605) mg/L of COD. A total organic loading of 2.76 kg biochemical oxygen demand (BOD)/(m3 packing d) was determined for the packed bed, in which the flow pattern approached that of a mixed flow. A limited VOC concentration of (0.97 0.29) ppmv (as methane) was emitted from the BAF system. Moreover, the emission rate of VOC was calculated using the proposed formula, based on an air-water mass equilibrium relationship, and compared to the simulated results obtained using the Water 9 model. Both estimation approaches of calculation and model simulation revealed that 0.1% IPA (0.0031–0.0037 kg/d) were aerated into a gaseous phase, and 30% to 40% (0.006–0.008 kg/d) of the toluene were aerated.