SMBR处理城市污水的同步脱氮除磷研究

通过对一体式膜生物反应器（SMBR）中试系统操作条件的调控,探讨了该装置在处理典型城市污水时的同步脱氮除磷功能.由于反应器具有不同的溶解氧分区,导致菌胶团内部同时存在好氧、缺氧、厌氧的微环境,使系统具有一定的同步脱氮除磷功能.试验结果表明,在曝气量为14.5 m3/h、水力停留时间为4.5 h、污泥浓度为8.0g/L时,出水COD、NH4＋-N符合《城市污水再生利用城市杂用水水质》（GB/T 18920-2002）,对总氮的平均去除率为45.6%,对总磷的平均去除率为43.1%.同时发现由过高的污泥浓度造成的溶解氧不足,是导致SMBR对氨氮去除效果不佳的主要因素.     

某化学合成制药类废水处理工艺的中试研究

采用微电解-UASB-AO组合工艺处理某化学合成制药类废水,研究了微电解HRT及污染物负荷对处理效果的影响。试验结果表明,在微电解HRT为10 h,UASB进水CODCr负荷为1.25~1.50 kg/(m~3·d),AO进水CODCr、NH_3-N、TN负荷分别为0.6、0.05和0.1 kg/(m~3·d)时,系统运行效果最佳,出水CODCr、NH_3-N、TN平均质量浓度分别为400、2、50 mg/L,出水水质达到了园区污水处理厂接管标准的要求。     

复合型生化反应器处理焦化废水的中试研究

提出了一种新的复合型生化反应器,并在工程现场,结合小试的结果进行了其处理实际焦化废水的中试研究。结果表明:在污泥浓度为4 g/L、温度为28℃下,厌氧水解10 h后,焦化废水的B/C值可由0.29升至0.62,可生化性明显改善。在5个月的连续流试验中,系统对COD、总氮、氨氮、挥发酚的去除率分别为94.1%、80%、93.3%、99.97%,出水COD浓度达到国家二级排放标准,出水氨氮、总氮、挥发酚、硫化物、氰化物浓度达到国家一级排放标准。     

废轮胎中试回转窑热解炭特性分析

采用中试回转窑热解装置对废轮胎进行了热解研究，在450—650℃热解试验温度范围内，热解炭产率约为39%—44%。热解炭的工业及元素分析显示，热解炭中灰分含量高达10％以上；含量最多的金属元素是Zn和Fe；热解炭S含量2．2%—2．6％左右，轮胎原料中S元素约75%留在热解炭中，因此热解过程中排放出的气体硫化物很少。此外，探讨了热解炭孔容积分布和温度对比表面积的影响，在450—550℃，热解炭比表面积随热解温度升高而增大；温度继续升高，比表面积变化不大，在孔半径约为25nm处，热解炭比孔容积有最大值。     

印度毛霉MJ229固态发酵产凝乳酶的研究

由于从小牛皱胃中提取的皱胃酶已无法满足干酪生产的需要,因而不得不寻找其他凝乳酶来替代小牛皱胃酶.本研究在前期小试实验基础上,研究毛霉MJ229固态发酵产凝乳酶的中试制备条件.确定其固态发酵培养基配方为:大米、麸皮和稻草的质量比为5:4:1,吐温-80为0.3％(w/w);加入自来水使液固比为1:1,最佳载曲量为每盘3kg.分别在自然状态与调控水分和温度状态下进行曲盘固态发酵试验,结果表明,毛霉MJ229在调节状态下发酵48h后获得凝乳酶活力可达5333Su/g,与自然发酵条件相比提高了25％.     

A~2/O/A/MBR中试装置的除污效能研究

在A~2/O工艺基础上,增加缺氧段并与膜分离相结合,构建了A~2/O/A/MBR强化生物脱氮除磷中试系统,并用于处理低碳源城市污水.经过两个阶段共60 d的调试后装置达到稳定运行.调试阶段的试验结果表明,在进水COD为88～440 mg/L、NH_4~+-N为7.49～46.7 mg/L、TN为15.17～47.56 mg/L、TP为1.52～4.96 mg/L的条件下,其出水平均浓度分别为21.36、1.09、9.62、0.19 mg/L,达到了GB 18918-2002的一级A标准.针对装置设计和机械故障问题,探讨了相应的解决方案,试验结果可为污水厂的提标改造提供设计和运行参考.     

Process for calcium retention during skim milk ultrafiltration

Lactose is separated from milk or other fluid dairy products for a variety of reasons. Ultrafiltration is a known process of removing lactose from these products. However, during ultrafiltration, valuable minerals, such as calcium in soluble form, are also lost into permeate. In this study, a process was developed in which first the lactose reduction in skim milk was achieved by ultrafiltration (4x volumetric concentration) using a 10-kDa membrane. Then, the calcium present in permeate was precipitated using one of three methods: 1) heat treatment, 2) pH adjustment, or 3) a combination of pH adjustment and heat treatment to permeate, then recovered by refiltering permeate. The process was first developed at laboratory scale, and then its applicability was tested at the pilot scale. Skim milk, retentates, permeates, and the treated permeates were analyzed for total solids, ash, protein, or total nitrogen, calcium, and lactose content. About 76% of the total lactose and about 16% of the calcium present in skim milk permeated through the membrane during ultrafiltration. The three treatments applied produced white precipitates and turned the clear permeates turbid. On refiltering the treated permeates approximately 42, approximately 50, and approximately 70% of the total calcium present could be recovered from 1) heat-treated, 2) pH-adjusted, and 3) pH-adjusted and heat-treated permeates, respectively. There was no marked change in the lactose content due to any of the three treatments and subsequent refiltering of the treated permeates.     

石煤电厂氨-亚硫酸氢铵WFGD特性研究

开发了一种石煤电厂氨-亚硫酸氢铵湿法烟气脱硫(WFGD)新工艺,并设计了烟气量为3 000 m³/h的中试试验装置.试验结果表明：吸收循环液的pH值是影响脱硫效率的主要因素.脱硫效率随pH值、液气比R的升高而增加;随烟气流速、循环液盐浓度的升高而降低.亚硫酸铵的氧化随循环液pH值、盐浓度的升高而降低.试验条件下,当pH=6时,脱硫效率可达98%以上,同时可以副产高浓度NH₄HSO₃溶液.     

自絮凝颗粒酵母酒精连续发酵新技术工业性放大试验研究

采用原生质体融合技术选育酒精发酵性能优良酵母菌株,在完成小试和中试工作基础上,建立了一套单级有效容积100m3,四级发酵罐串联,年产酒精万吨级规模工业性放大试验装置。发酵终点酒精浓度平均达到12%(v/v),平均发酵时间缩短10h左右。同时,酒精发酵过程副产酵母采用自沉降分离。     

Influence of sawdust addition on drying of wastewater sludges: Comparison of structural characteristics

ABSTRACT

This work aims to investigate the structural characteristics of wastewater sludges and sludge–wood mixtures, and how the addition of sawdust affects them in a positive way for the drying process. The study was performed for a fixed bed at the pilot scale, with sludges from three different wastewater treatment plants from the Liège province in Belgium, namely, Oupeye, Grosses Battes, and Embourg. X-ray tomography was chosen to evaluate variations in the structural characteristics before and after drying, which included volume, void fraction, and exchange surface of the bed. Results first confirm that the drying rate is raised after the sawdust addition operation for all three sludges, but the increase amount is smaller while the moisture of the sludge is high. With sawdust, the average drying rates increase by factors of 1.475 (Oupeye), 1.342 (Grosses Battes), and 1.162 (Embourg), respectively. It also increases initial volume as well as void fraction and surface exchange, however after drying this addition leads to less shrinkage and void fraction, and higher exchange surface. The initial void fraction increases by 7.25 (Oupeye), 8.30 (Grosses Battes), and 14.01% (Embourg), but the final void fraction decreases 1.56 (Oupeye), 10.83 (Grosses Battes), and 25.61% (Embourg). With high initial moisture content, we observed lower porosity and higher shrinkage.