EMMC process for combined removal of organics, nitrogen and an odor producing substance

In order to improve the process performance regarding the removal of organics, nitrogen, and an odor-causing compound (sulfide) contained in domestic wastewater, an entrapped-mixed-microbial cell (EMMC) with and without humic substances for both fixed and moving carrier reactors and conventional suspended growth culture (i.e. conventional activated sludge process) were investigated simultaneously. Both synthetic (simulated to the organics concentration of general domestic sewage) and actual domestic wastewater were investigated under operational conditions of 12 h of hydraulic retention time (HRT) with 1 h of aeration and 1 h of non-aeration, and 6 h of HRT with continuous aeration, at a room temperature of 25 +/- 2 degrees C. It was found that entrapping humic substances in the EMMC carriers had no impact on the removal of organics, nitrogen, and the odor-producing compound. Additionally, the performance of the EMMC moving carrier system for the removal of these pollutants is similar to that of the EMMC fixed carrier system. In general, the EMMC associated systems which provide high solids retention time achieve a better removal of chemical oxygen demand (COD), nitrogen, and the odor-producing substance than the suspended growth system for both HRTs of 6 h (continuous aeration) and 12 h (1 h of aeration and 1 h of non-aeration). Both the fixed and moving carrier EMMC processes, therefore, have the potential for improvement or replacement of the existing conventional activated sludge process with regard to improving the effluent qualities (such as COD, nitrogen and odor-producing compound) for reuse/disposal.     

Fuzzy multiple-criteria decision-making approach for industrial green engineering

This paper describes a fuzzy hierarchical analytic approach to determine the weighting of subjective judgments. In addition, it presents a nonadditive fuzzy integral technique to evaluate a green engineering industry case as a fuzzy multicriteria decision-making (FMCDM) problem. When the investment strategies are evaluated from various aspects, such as economic effectiveness, technical feasibility, and environmental regulation, it can be regarded as an FMCDM problem. Since stakeholders cannot clearly estimate each considered criterion in terms of numerical values for the anticipated alternatives/strategies, fuzziness is considered to be applicable. Consequently, this paper uses triangular fuzzy numbers to establish weights and anticipated achievement values. By ranking fuzzy weights and fuzzy synthetic utility values, we can determine the relative importance of criteria and decide the best strategies. This paper applies what is called a λ fuzzy measure and nonadditive fuzzy integral technique to evaluate the synthetic performance of green engineering strategies for aquatic products processors in Taiwan. In addition, we demonstrate that the nonadditive fuzzy integral is an effective evaluation and appears to be appropriate, especially when the criteria are not independent.     

高效生物处理技术在炼油厂碱渣废水处理中的应用

结合大港石化实际情况,在详细介绍柴油碱渣应用QBR高效生物处理技术取得成功的基础上,提出酸化回收粗酚或环烷酸并配套QBR、QBF等高效生物处理技术处理各种碱渣的新型工艺路线。经QBR处理后,出水COD去除率可达97%以上,石油类和挥发酚的去除率可达98%以上,硫化物去除率在99%以上。该技术的成功应用解决了困扰石化公司多年的碱渣废水处理的老大难问题,为炼厂碱渣废水乃至高浓度有机废水的处理开辟了一条新的途径。     

二次催化-固定床生物氧化降解焦化废水的试验研究

制备了一种铁碳基／过渡金属复合催化剂，其物质摩尔配比为Fe：C：TiO2：MnO2：ZnO=2：1：1：1：0．3，使用该催化剂拟定了二次催化—固定床生物氧化降解流程。在pH＝6、温度=90℃的条件下，用该流程处理煤化工工业所产生的洗煤气净化脱酚、蒸氨剩余废水，在无需对原废水进行稀释的前提下可很好地对此废水进行处理，使处理后的出水指标达到《污水综合排放标准》（GB89r78—1966）中规定的二级排放标准。     

催化湿式氧化法处理吡虫啉农药废水

自制了Cu／Mn，Cu／Ce，Cu／Ni，Ce／Mn，Ce／Ag等催化剂，经过性能比较，选择催化活性较高且金属溶出量较小的Cu／Ni作催化剂。用催化湿式氧化法处理吡虫啉农药废水，考察了各种因素对处理效果的影响。实验结果表明：在进水pH为6．93、Cu／Ni加入量为4．0g、反应温度为190oC、氧分压为1．6MPa、反应时间为120min的条件下，COD去除率为95％；处理后废水的BOD5／COD从0．093增至0．590，可生化性明显改善。     

微生物絮凝剂处理造纸中段废水的实验研究

实验从土壤中分离筛选出1株絮凝活性较高的絮凝剂产生菌,经鉴定为1株黑曲霉.采用其产生的微生物絮凝剂M-2处理造纸中段废水,对絮凝条件进行了优化,在最佳絮凝条件下,M-2对造纸中段废水的CODcr去除率可达70.6%,浊度去除率可达91.7%,其絮凝效果优于传统的絮凝剂.     

环境物探技术在岩溶勘察中的应用及其效果

将高密度电阻率法及工程地震映像法两种环境物探技术同时应用于实际的地质灾害(岩溶)勘察中,结果表明:对于岩溶这样的地质灾害,单一环境物探技术虽然能清楚反映其埋深、规模和发育情况,但各有缺陷。而多种环境物探技术的综合使用,相互补充,将能大大提高岩溶勘察的准确性,提高勘察效果和效率。     

工程监理的安全责任研究

为了研究工程监理单位是否应该承担安全监理的责任问题,从工程监理制度与安全施工的关系,从法律、行政法规、技术规范等多方面对工程监理的安全责任进行了全面的分析和详细的研究,最后从法理和现实入手,对工程监理单位的安全责任进行了总结和归纳,对一些条文规定进行了深入的解析。研究结果表明,目前的《建设工程安全生产管理条例》和某些地方政府和行业主管部门对工程监理单位的安全监理责任有扩大化的倾向,应予以制止。     

工科学生工程安全素质培养的探索与实践

高等学校工科学生的社会职业定位是工程师,工程师的主要工作是从事工程的规划、设计、实施、运行和管理,其工程行为对工程安全具有至关重要的影响。随着现代工程向大型化、综合化和复杂化方向发展,工程安全已成为人类社会面临的重大问题,解决工程安全问题的根本途径之一是加强和改进高等工程教育,致力于提高工科学生的工程安全素质培养。对工科学生的工程安全素质培养,各高校可根据自己的专业优势和服务需求面而独具特色,以适应社会对工程安全人才多样性要求。湖南科技大学在工科学生的培养中,从培养目标的改革中加强了对工程安全素质的要求;从培养内容的改革中加强了对工程安全知识的传授;从培养方法的改革中加强了对工程安全技能的训练;各项改革中的措施在实践中取得令人满意的效果。     

Nitrogen recovery in an integrated system for wastewater treatment and tilapia production

An integrated system, consisting of Up-flow Anaerobic Sludge Blanket (UASB)-duckweed-tilapia ponds was used for recovery of sewage nutrients and water recycling. A UASB reactor with 40 liter working volume was used as pre-treatment unit followed by a series of three duckweed ponds for nitrogen recovery. The treated effluent and duckweed biomass was used to feed fishponds stocked with Nile tilapia (Oreochromis niloticus). The UASB reactor was fed with raw, domestic sewage at 6 h hydraulic retention time. The three duckweed ponds were stocked with Lemna gibba and fed with UASB effluent at 15 days hydraulic retention time. Nitrogen recovery from UASB effluent via duckweed biomass represented 81% of total nitrogen removal and 46.5% from the total nitrogen input to the system. In subsequent fishponds the nitrogen recovery from duckweed as fish feed was in the range of 13.4–20%. This nitrogen in fish biomass represented 10.6–11.5 g N from the total nitrogen in the raw sewage fed to the UASB reactor. The growth performance of tilapia (Oreochromis niloticus) showed specific growth rates (SGR) in the range of 0.53–0.97. The range of feed conversion ratio (FCR) and protein efficiency ratio (PER) were 1.2–2.2 and 2.1–2.28, respectively. The results of the experiments showed total fish yield and net fish yield in the range of 17–22.8 ton/ha/y and 11.8–15.7 ton/ha/y respectively. In conclusion UASB-duckweed-tilapia ponds provide marketable by-products in the form of duckweed and fish protein, which represent a cost recovery for sewage treatment.