Carbofuran removal in continuous-photocatalytic reactor: Reactor optimization,rate-constant determination and carbofuran degradation pathway analysis

Carbofuran (CBF) removal in a continuous-flow photocatalytic reactor with granular activated carbon supported titanium dioxide (GAC-TiO₂) catalyst was investigated. The effects of feed flow rate, TiO₂ concentration and addition of supplementary oxidants on CBF removal were investigated. The central composite design (CCD) was used to design the experiments and to estimate the effects of feed flow rate and TiO₂ concentration on CBF removal. The outcome of CCD experiments demonstrated that reactor performance was influenced mainly by feed flow rate compared to TiO₂ concentration. A second-order polynomial model developed based on CCD experiments fitted the experimental data with good correlation (R² ～ 0.964). The addition of 1 mL min^?1 hydrogen peroxide has shown complete CBF degradation and 76% chemical oxygen demand removal under the following operating conditions of CBF ～50 mg L^?1, TiO₂ ～5 mg L^?1 and feed flow rate ～82.5 mL min^?1. Rate constant of the photodegradation process was also calculated by applying the kinetic data in pseudo-first-order kinetics. Four major degradation intermediates of CBF were identified using GC-MS analysis. As a whole, the reactor system and GAC-TiO₂ catalyst used could be constructive in cost-effective CBF removal with no impact to receiving environment through getaway of photocatalyst.     

曝气生物滤池用于分散型污水处理及其动力学浅析

将曝气生物滤池用于分散型污水处理,分析了反应器在不同水力负荷条件下对污染物的去除效果,同时从动力学角度对反应器作了浅析,总结出一个动力学模型.实验证明,该模型对出水水质预测和水力负荷条件的确定具有一定的工程实践指导作用.     

臭氧/活性炭/紫外光联用处理几种高浓度有机废水影响因素

以对硝基苯甲酸废水、鸟嘌呤废水、乙醛废水和乙醇胺废水为例,对臭氧/活性炭氧化去除废水中有机物的效果进行了初步研究,考察了臭氧投加量、pH值和紫外光等因素对臭氧/活性炭催化氧化高浓度有机废水的影响,并在最优条件下,验证了该工艺作为高浓度有机废水预处理手段,在去除废水中COD和提高可生化性(BOD5/COD)等方面的综合效果.结果表明,活性炭作为催化剂与臭氧共同作用,对对硝基苯甲酸废水COD的去除率明显高于单独臭氧氧化和活性炭吸附;臭氧/活性炭氧化对乙醛废水和乙醇胺废水这类短链类有机物降解作用不大,但对硝基苯甲酸废水、鸟嘌呤废水这些含有苯环类、长链类的有机物,去除效率较高;在中性偏碱时,pH的提高有利于COD的去除,但过高pH对COD的降解效果反而有所减弱,pH=9.0是比较合适的;在紫外光催化的条件下,采用臭氧/活性炭氧化工艺处理对硝基苯甲酸废水,COD去除率可达到52%,废水的生化性(BOD5/COD)由原来的0.10提高到0.32,大大提高了废水的可生化性.     

Combination of adsorption and biodegradation processes for textile effluent treatment using a granular activated carbon-biofilm configured packed column system

The objective of this study was to investigate the feasibility of using a granular activated carbon-biofilm configured packed column system in the deeolodzation of azo dye Acid Orange 7-containing wastewater.The Acid Orange 7-degrading microbial from anaerobic sequencing batch reactor which treating the azo dye-containing wastewater for more than 200 d was immobilized on spent granular activated carbon(GAC)through attachment.The GAC-biofilm configured packed column system showed the ability to decolorize...     

颗粒活性炭促进高温厌氧消化的研究

近年来的研究表明,颗粒活性炭（GAC）可以通过种间电子传递（DIET）过程,来提高中温厌氧消化（MAD）产甲烷.然而,GAC是否能够提高高温厌氧消化（TAD）产甲烷,以及其促进产甲烷原理尚不明确.通过乙酸钠为基质的批试验研究了投加GAC对高温消化产甲烷的影响.批试验结果表明GAC的加入促进了高温消化效果.定量PCR结果表明GAC的加入对生物量的贡献微小,说明促进效果可能不是通过生物量实现的.高通量测序结果发现高温下添加GAC富集了Thermodesulfolbiaceae,Anaerobaculaceae,以及古菌Methanosacinacea.该研究推测GAC的促进作用可能与直接种间电子传递有关.     

Analysis of the selected optical parameters of filters protecting against hazardous infrared radiation

The paper analyses the selected optical parameters of protective optic filters used for protection of the eyes against hazardous radiation within the visible (VIS) and near infrared (NIR) spectrum range. The indexes characterizing transmission and reflection of optic radiation incident on the filter are compared. As it follows from the completed analysis, the newly developed interference filters provide more effective blocking of infrared radiation in comparison with the currently used protective filters.     

碳基吸附剂对典型有机防晒剂二苯甲酮-3的吸附性能及热力学研究

针对环境水体中药物及个人护理用品(PPCPs)的污染问题,选择在环境水体中存在的有机紫外防晒剂二苯甲酮-3(BP-3)作为典型污染物,以颗粒活性炭(GAC)、粉末活性炭(PAC)和碳纳米管(CNT)作为吸附剂,考察吸附剂对BP-3的吸附性能、吸附特性和吸附热力学.结果表明:吸附性碳材料对BP-3具有良好的吸附性能,3种碳材料的最大吸附容量排列为:PACGACCNT,其中,PAC的单层最大吸附容量为450.36mg·g-1.Freundlich、Redlich-Peterson和Temkin吸附等温线方程能够较好地拟合吸附数据,Langmuir吸附等温线方程对PAC的吸附拟合效果较好,而对粒径较大的吸附剂(GAC、CNT)的拟合效果不理想.PAC、GAC的吸附过程可以采用一级动力学或者二级动力学模型拟合,而CNT适合采用一级动力学模型来描述.吸附热力学分析表明,PAC、GAC和CNT对BP-3的吸附过程都是自发进行的,其中,PAC和GAC的吸附过程是吸热的,升高温度有利于吸附反应的进行;而CNT的吸附过程是放热的.     

Some properties of a granular activated carbon-sequencing batch reactor (GAC-SBR) system for treatment of textile wastewater containing direct dyes

Resting (living) bio-sludge from a domestic wastewater treatment plant was used as an adsorbent of both direct dyes and organic matter in a sequencing batch reactor (SBR) system. The dye adsorption capacity of the bio-sludge was not increased by acclimatization with direct dyes. The adsorption of Direct Red 23 and Direct Blue 201 onto the bio-sludge was almost the same. The resting bio-sludge showed higher adsorption capacity than the autoclaved bio-sludge. The resting bio-sludge that was acclimatized with synthetic textile wastewater (STWW) without direct dyes showed the highest Direct Blue 201, COD, and BOD(5) removal capacities of 16.1+/-0.4, 453+/-7, and 293+/-9 mg/g of bio-sludge, respectively. After reuse, the dye adsorption ability of deteriorated bio-sludge was recovered by washing with 0.1% sodium dodecyl sulfate (SDS) solution. The direct dyes in the STWW were also easily removed by a GAC-SBR system. The dye removal efficiencies were higher than 80%, even when the system was operated under a high organic loading of 0.36kgBOD(5)/m(3)-d. The GAC-SBR system, however, showed a low direct dye removal efficiency of only 57+/-2.1% with raw textile wastewater (TWW) even though the system was operated with an organic loading of only 0.083kgBOD(5)/m(3)-d. The dyes, COD, BOD(5), and total kjeldalh nitrogen removal efficiencies increased up to 76.0+/-2.8%, 86.2+/-0.5%, 84.2+/-0.7%, and 68.2+/-2.1%, respectively, when 0.89 g/L glucose (organic loading of 0.17kgBOD(5)/m(3)-d) was supplemented into the TWW.     

Analysis of the recycling potential of used automotive oil filters using the Life Cycle Assessment approach

The aim of this study is to evaluate whether a specific recycling system for used oil filters (UOFs) is environmentally viable by considering all steps of the product's life cycle. In that aspect an analysis of the environmental impacts regarding different waste management scenarios of UOFs in Greece is presented using the Life Cycle Assessment (LCA) approach. Waste scenarios varied from maximum feasible recycling and recovery of metals and used lubricant oil, to disposal of UOFs to landfills without any prior treatment. In order to perform this analysis, the principles of ISO 14040 were followed and a relevant LCA software was used (SimaPro 7.2). Additionally, the results of a previous work conducted by the authors were deployed, including some experimental measurements undertaken so as to evaluate and quantify the factors affecting the recovery of the lubricant oil contained in used automotive filters. Indicatively, it was estimated that a maximum of 1340 tons of used oil and 1810 tons of steel are disposed every year in Greece, as a result of the non-effective management of used automotive filters.     

有机紫外吸收剂BP-3的厌氧污泥降解特性

2-羟基-4-甲氧基二苯甲酮（BP-3）作为化学品添加剂广泛应用于防晒霜、化妆品和染色剂等个人护理品以及塑料制品,用于吸收紫外线防止皮肤晒伤、材料老化和腐蚀.经使用后BP-3随污水排放或者人类涉水活动直接或间接排放到受纳水环境.因BP-3属于疏水性化合物,进入水环境后更易于分配至污泥和沉积物等缺氧和厌氧环境,厌氧微生物降解是BP-3重要的自然消减过程.然而,目前BP-3在不同厌氧条件下的降解转化机制仍不清楚.本研究以城市污水处理厂厌氧污泥为接种体,对比分析了不同厌氧还原条件和碳源共代谢对BP-3厌氧降解转化的差异.研究结果表明,硝酸盐、硫酸盐还原条件抑制BP-3的厌氧降解,而额外添加混合碳源可促进BP-3的降解（最短降解半衰期为1.285 d）.通过对混合碳源体系厌氧菌群驯化培养,BP-3降解能力显著提高,降解半衰期缩短至0.734 d （10 mg·L^-1）.利用UPLC-QTOF-MS鉴定主要降解中间产物为2,4-二羟基二苯甲酮（BP-1）,推测其厌氧降解转化主要途径为去甲基化.筛查获得了一株BP-3高效厌氧降解单菌,通过16S rDNA测序比对确定为柠檬酸杆菌属兼性厌氧菌.