基于氧猝灭的有机改性溶胶-凝胶微生物传感器测定BOD的研究

通过有机改性溶胶凝胶PVA包埋方法固定微生物菌株，以氧光化学传感器作为二次传感，制备了响应良好的光化学BOD微生物传感器．在此基础上，考察了微生物传感膜的活化浓度、温度、pH、无机盐及部分金属离子对传感器响应的影响．并对传感器的重现性、储存稳定性和线性范围进行了考察，实验结果表明BOD含量在0—100mg/L浓度范围内与传感器的荧光值成线性关系，传感膜的响应活性保持较好，具有较长的使用寿命和良好的稳定性．     

测定废水BOD5时水样稀释倍数的确定

根据测定BOD5所须具备条件,经过理论推导,得出水样稀释倍数的大致范围,对多种工业废水测试证,表明方法简便易行。     

黄姜废水的铁炭微电解-混凝预处理研究

研究了高浓度黄姜废水的铁炭微电解-混凝工艺,结果表明,在进水pH 4.0、停留时间为40 min且有曝气条件下,COD去除率达到64.70%,色度去除率为72.22%,废水的BOD/COD值可由0.29提高到0.56,有利于废水的后续生化处理.     

生物接触氧化预处理微污染源水中BOD5的测定

在微污染源水生物预处理中,由于生物池内和处理后的出水中含有大量硝化细菌,使BOD5测定结果偏大.提出在测定这类水样时,加入硝化细菌抑制剂,可以消除硝化作用的影响.     

沙渗滤去除三家店水库水中有机污染物的试验研究

采用CODMn和BOD作为指标对沙渗滤系统去除三家店水库水中有机污染物的效果进行了评价.试验构建一个长约10m、宽2m、高2m的砖混结构渗滤池,渗滤池分隔为8个小渗滤池,选择3种不同的沙分别构建1m3见方的渗滤床.渗滤系统持续运行125d,经历高温的夏季和低温的冬季,试验结果表明,渗滤系统对三家店水库水中有机污染物能有效去除,CODMn去除率一般在20%～40%,BOD的去除率一般在20%～80%,CODMn、BOD的出水值分别小于4mg·L-1、3mg·L-1;渗滤层厚度的增加不能显著增加有机污染物的去除率;温度对CODMn和BOD的去除有明显的影响;3种渗滤介质对CODMn和BOD均能有效去除,建筑沙对去除有机质的效果相对好一点.     

废水可生物降解COD组分2种表征方法的比较

利用自行开发的混合呼吸速率测量仪在接种污泥的条件下对重庆某城市污水处理厂污水进行了呼吸速率测试（短期BOD测试,以呼吸速率测量重新进入内源呼吸阶段为结束）;同时应用美国产BI-2000电解质呼吸仪在不接种污泥的条件下对该污水进行了BOD测试（长期BOD测试,理论上以污水中所有有机物矿化为结束）。对2种测试方法及其结果进行了比较,结果表明,2种方法得到的BCOD存在很大差异,短期BOD测试方法得到的结果仅为长期BOD测试方法得到的结果的40％～60％。通过批式呼吸测量方法测定了原废水中的活性异养微生物浓度XH(0),结果表明,XH(0)与BCOD_st之和与BCOD_lt比较接近,两者之比在0.88～1.02之间,平均值为0.94。     

Nitrification/denitrification in an intermittent aeration process for swine wastewater

Abstract

Nitrogen removal by a methane fermentation plus activated sludge process with the intermittent aeration was presented based upon a full‐scale pig farm experiment. Swine wastewater had a T‐N/BOD ratio from 0.2–0.29. The BOD concentration input to the process ranged from 1050–1608 mg l^‐1 and the T‐N concentration from 273–350 mg l^‐1. More than 90% of organic carbon was removed in each experimental run. Only small concentrations of NO₃‐N were found in the effluent and higher than 60% of the T‐N and 73% of NH₄‐N which were loaded to the intermittent aeration tank was removed. The nitrogen balance of each run was calculated. Denitrification was estimated to be accountable for 45–90% of the T‐N removed in the intermittent aeration tank. Denitrification rate increased as the BOD concentration increased (> 1300 mg l^‐1). The T‐N removal percentage was a function of the T‐N/BOD ratio of the influent. Although higher DO concentration (> 3 mg l^‐1) did not enhance the denitrification rate, nitrification did maintain at relative higher rates at a lower DO concentration (ave. 1.5 mg l^‐1). An operational condition of intermittent interval of aeration/nonaeration at 1:1 hr is better than that of the condition at 3:1 hr. As a result, T‐N and NH4‐N were removed up to 30% and 40% respectively, and the denitrification rate reached 79% in the intermittent aeration tank. An experimental run in a pilot plant on treating anaerobically pretreated swine wastewater was observed to verify simultaneous nitrification/denitrification. The results of the full‐scale plant experimentation seem to be confirmed by those obtained from the pilot plant runs.     

双室微生物燃料电池型BOD传感器性能

构建了双室微生物燃料电池(MFC),并应用于污水BOD的检测。优化了MFC型BOD传感器的检测条件,分析了传感器进行污水BOD检测的特征。结果表明,以A2/O污水处理工艺中厌氧段污泥进行接种,双室MFC型BOD传感器2周内完成启动,所产电流达到稳定。传感器的最佳检测条件为外接电阻500Ω,添加缓冲溶液并维持待测水样pH为7.0,添加35 mg/L的L-半胱氨酸作为吸氧剂维持阳极室厌氧环境,阴极室富氧水流量为20 mL/min。利用MFC产生的电流峰值准确检测污水水样BOD浓度,传感器检测范围为10~50 mg/L,检测时间小于3 h;利用MFC产生的电荷量准确检测污水水样BOD浓度,检测范围为10~100 mg/L,检测时间小于10 h。利用MFC电流峰值和电荷量检测污水水样BOD浓度,偏差均小于15%,传感器运行稳定,寿命较长。     

A potential new commercial method for processing leather to reduce environmental impact

INTRODUCTION: Current leather processing method involves dehairing and fibre opening employing lime and sulphide, which results in higher negative impact on the environment due to its uncleanness. This method of dehairing and fibre-opening process accounts for nearly 70-80% biochemical oxygen demand and chemical oxygen demand (COD) in tannery wastewater and also the generation of H(2)S gas. MATERIALS AND METHODS: Hence, an attempt has been made to reduce the environmental impact of the leather processing through a biochemical approach, employing proteolytic enzyme and sodium metasilicate for performing the above process more cleanly. RESULTS AND DISCUSSION: The developed process exhibits significant reduction in environmental parametres such as COD and total solid loads by 55% and 25%, respectively. This method completely avoids the formation of lime sludge. CONCLUSION: The functional properties of the leathers are also on par with conventionally processed leathers. Further, the process seems to be commercially viable.     

Effectiveness of Treatment Technologies for Wastewater Pollution Generated by Indian Pulp Mills

India has a large number of paper manufacturing units, with mills varying in size of operations and type of product, scattered all over the length and breadth of the country. Present study deals with the survey of four different pulp and paper mills (Mill A, Mill B, Mill C and Mill D) in India, differing in their scale of operation as well as raw material usage. Physico-chemical characterization of wastewaters produced by different processing units like digestor house liquors, bleaching section, paper machine backwaters, combined inlet to the ETP and outlet to ETP, for all the four mills, was conducted. Different parameters like pH, Color, COD, BOD, percent Na, SAR, TDS and Total hardness were analyzed and compared. Highly significant differences were thus found between all the processing units of all four mills with p values < 0.01. This evaluation showed that though these mills have effluent treatment facilities installed in their premises, improvements are still needed to increase their efficiencies for treating the discharged wastewaters.