Optimization of the operating conditions in a TiO2/Fe3O4-SiO2 photocatalytic reactor for the treatment of industrial wastewater containing Procion Red MX-5B

According to the design principle of the central composite experimental,the method of response surface analysis with three factors and three levels was adopted based on one factor test.A second-order quadratic equation for photocatalysis of Procion Red MX-5B was built.Response surface and contour were graphed with the decoloration rate of Procion Red MX-5B as the response value.Based on the analysis of the response surface plots and their corresponding contour plots,effects of pH value,irradiation time and catalyst loading were explored.By using this new method,the optimum decoloration condition was obtained as follows:pH value,1.3;irradiation time,49.9 min;catalyst loading,0.57 g/L.In the optimization,R-Squared and Adj R-Squared correlation coefficients for quadratic model were evaluated quite satisfactorily as 0.9310 and 0.8620,respectively.Under the optimum conditions established,the performance of 99.47% for color removal was experimentally reached.It was found that all factors considered have an important effect on the decolorization efficiency of Procion Red MX-5B.By the ANOVA analysis and model confirmation the optimal solution obtained using RSM was experimentally validated and credible with preferable instructional ability for experiments.     

Growth properties of mixed liquor suspended solids in SMBR for pharmaceutical wastewater treatment

This paper presents the performance results of a 366-day pilot-scale submerged membrane bioreactor (SMBR) for treating high-strength pharmaceutical wastewater. The study focuses on the growth properties of mixed liquor suspended solids (MLSS) in SMBR operated at high volumetric loading rates. The influences of MLSS on COD removal,sludge yield,oxygen utilization rates and sludge viscosity are studied. Results show that the bioreactor can be operated at higher volumetric loading rate with a low sludge yield. VSS/SS and observed sludge yield coefficient (Yo) present a decreasing trend with the decrease of hydraulic retention time (HRT) . Sludge oxygen utilization rate decreases with the increase of mixed liquor volatile suspended solids (MLVSS) . A mathematical model between sludge viscosity and MLSS is developed.     

铝盐和铁盐混凝对切削液废水中有机物的去除特性

采用PAC和PFS混凝处理切削液废水,并通过超滤膜法将水中有机物分子质量分级,考察混凝前后废水中有机物分子质量分布,可生物降解性及紫外光谱的变化。结果表明,原废水含大量共轭双键和不饱和芳香物质;PAC和PFS混凝剂最佳投加质量浓度均在9 g/L,相应的去除率分别为78.2%、38.2%,其中PAC对大分子有机物的去除率高于PFS,但两者对小分子有机物的去除效果均较差。与PFS相比,PAC改善了废水的可生物降解性。     

微藻吸收利用CO2的影响因素及吸收能力研究

为了研究微藻吸收CO2的优化条件,提高微藻对CO2的吸收利用率,设计了微藻吸收CO2反应装置,研究了在自然光照条件下体系初始pH值、光照强度、入口CO2浓度及微藻初始浓度4个因素对微藻吸收CO2的影响.实验结果表明,在体系初始pH值控制在9.0左右、光照强度1.5×104lux、入口CO2浓度10%和微藻初始浓度控制在1 000 mg/L条件下,反应体系吸收CO2的能力最强,装置对CO2的吸收量可达1.73 g/(L.d),微藻利用CO2的效率为8.24 g/(g.d).利用微藻吸收CO2既可减少碳排放,又可实现碳利用(产生生物质),是很有实用价值的减排技术.     

考虑制造商设备维修的制造—零售供应链决策与协调

设备可靠性是影响供应不确定的重要因素。为了研究企业内部的维修策略对整条供应链的运营策略产生的具体影响，在考虑设备维修的情况下，针对单个制造商和单个零售商构成的二级供应链，运用Stackelberg博弈的方法研究制造商的最优维修策略和定价策略以及零售商的最优订货量。研究结果表明，制造商的预防性维修次数存在上限且最大维修次数与设备可靠性无关；预防性维修策略有助于提高制造商的产量，降低产品的批发价格，但制造商的最优产出量不会达到企业的最大产能；收益共享契约能够实现供应链的协调；制造商在任何情形下都具有提高设备可靠性的动机，但零售商只会在市场规模较大时才存在为制造商提供设备改造资金的动机。     

基于HFACS的煤矿安全事故编码研究

我国煤矿事故数量大,对其进行科学的归类、编码,建立规范性、易用性、可扩充性数据库,有利于煤矿安全事故的统计分析和安全问题的解决。基于人因分析和分类系统(HFACS)对煤矿安全事故进行编码处理。通过构建煤矿安全事故的人因数据库,可分析得到造成煤矿安全事故的主要人因,为煤矿安全事故的预防提供一定参考。     

民族院校环境类专业综合改革

针对民族院校的学生特点和民族地区对环境类专业技术人才的需求,以及国家对高等教育培养"卓越工程师"的要求,结合大连民族学院环境类专业近年的建设情况,从教学团队建设、强化课程的时效性和课程之间的有效衔接以及知识的系统性、创新型工程技术人才培养平台构建等方面,阐述了民族院校环境类专业综合改革的做法,以期寻求适合社会需求的高等教育培养模式。     

通过优化预分配算法提升CDMA数据能力

提出采用优化预分配算法来提升CDMA数据能力。实施效果表明在前向平均速率、SCH话务量、空口前向流量、闲基站和忙基站服务能力、业务低速和高速比例等5个方面都得到了显著提升。     

MBR处理含7-ACA废水的影响因素研究

采用MBR工艺处理含7-ACA废水,考察了进水7-ACA浓度、DO浓度、pH值、温度等因素对处理效果的影响。结果表明,随着进水7-ACA浓度的升高,对7-ACA的去除效果先升高后下降,当进水7-ACA浓度为30 mg/L时,对7-ACA的去除率最高,为65.6%;另外,在进水7-ACA浓度为100 mg/L的条件下,MBR处理含7-ACA废水的最佳参数如下:DO浓度为2.5~3.5 mg/L、pH值为7~9、温度为35℃。