Penetration analysis of elements and bioleaching treatment of spent refractory for recycling

Acidithiobacillus ferrooxidans ATCC23270 and Acidithiobacillus thiooxidans TM-32 were used for bioleaching of spent refractories of aluminium and copper melting furnaces for their recycling.Firstly,penetration of elements into aluminium melting furnace refractory was investigated and it was found that up to 7 cm from surface was contaminated.Comparison on leaching efficiency by the strains ATCC23270 and TM-32 found that the strain ATCC23270 could treat larger amount of the refractories than the strain TM-32 could do.In the experiment of bioleaching of spent refractory aluminium melting furnace by the strain ATCC23270,high leaching efficiency were obtained on Al,Si,and Ca,and extremely low leaching performance was,however,shown on the rest of elements i.e.,Na,Mn,and Zn.Under the strain TM-32 use,relatively high leaching performance was recognized on Al,Si,Ca,Na,Mn,and Zn.In the experiment of bioleaching for spent refractory copper melting furnace,almost the same leaching trends were shown on Cu,Zn,Al,and Si under the strains ACTT23270 and TM-32 uses.     

Nitric oxide removal by wastewater bacteria in a biotrickling filter

Nitric oxide(NO) is one of the most important air pollutants in atmosphere mainly emitted from combustion source. A biotrickling filter was designed and operated to remove NO from an air stream using bacteria extracted from the sewage sludge of a municipal sewage treatment plant. To obtain the best operation conditions for the biotrickling filter, orthogonal experiments(L9(34)) were designed. Inlet oxygen concentration was found to be the most significant factor of the biotrickling filter and has a significant negative effect on the system. The optimal conditions of the biotrickling filter occurred at a temperature of 40℃, a pH of 8.0 and a chemical oxygen demand of 165 mg/L in the recycled water with no oxygen in the system. The bacteria sample was detected by DNA sequencing technology and showed 93%–98% similarity to Pseudomonas mendocina. Moreover, a full gene sequencing results indicated the bacterium was a brand new strain and named as P. mendocina DLHK. This strain can transfer nitrate to organic nitrogen. The result suggested the assimilation nitrogen process in this system. Through the isotope experimental analysis, two intermediate products(15NO and 15N2O) were found. The results indicated the denitrification function and capability of the biotrickling filter in removing NO.     

强化混凝处理制革废水的优化研究

对皮革废水混凝处理的条件进行优化,分别采用FeSO4·7H2O和阳离子聚丙烯酰胺作为混凝剂和助凝剂,以COD、总铬和硫化物为指标,设计正交试验确定强化混凝处理皮革废水的最优条件并进行验证性试验。结果表明:当FeSO4·7H2O投加量为1800mg/L,阳离子聚丙烯酰胺投加量为7.5mg/L,pH为10,混凝效果最好,对COD、总铬和硫化物的平均去除率分别为14.92%、99.40%和99.71%。     

铁碳微电解处理硝基苯废水的实验研究

文章以硝基苯废水为研究对象,设计了正交实验,影响铁碳填料修复效果的参数主要有pH值、停留时间、Fe/C比,实验结果表明pH值和停留时间为显著因素,Fe/C比较为显著,并得出最佳条件。通过本实验确定的显著因素和最佳条件为硝基苯废水的处理提供了有力的理论支持和科学依据。     

组合流反应器启动运行试验

以含氮磷的模拟生活污水为处理对象,对自行设计的推流、折流与完全混合流的组合流动反应器进行启动试验研究。试验分为两个部分,首先对普通活性污泥进行驯化培养,然后将驯化好的活性污泥移到组合流反应器内,加入污水进行连续启动运行。试验连续运行30 d,结果表明在启动运行后期,COD、TP、氨氮的去除率分别达85%、80%及70%以上,好氧区硝态氮的累积率稳定在28 mg/L,说明组合流反应器启动成功。     

改性颗粒活性炭吸附低浓度甲醛的试验研究

通过试验研究了表面改性方法、焙烧气氛和气相水分对颗粒活性炭(GAC)吸附低浓度甲醛性能的影响。结果表明:3%HNO3浸泡改性可增加GAC表面的含氧官能团,显著改善GAC对甲醛的吸附性能,并延长吸附穿透时间;O2气氛下焙烧所得GAC的吸附效果优于N2气氛下焙烧的GAC;反应气体含水1.5%时,GAC对甲醛的吸附性能明显降低。另外,分别采用低温N2吸附法和傅立叶红外光谱法表征了3%NHO3浸泡改性前、后GAC的孔结构和孔表面化学性质的差别,从而揭示了GAC的吸附性能与孔结构、孔表面化学性质之间的关系。     

聚丙烯酰胺对生活污泥脱水的实验研究

设置了聚丙烯酰胺的投药量、搅拌速度、絮凝温度、p H 4个影响因素,研究了聚丙烯酰胺在污泥絮凝的过程中,污泥的沉降性能和脱水性能。在单因素实验的基础上,进行了响应面分析试验,经过优化得到最优条件为投加量50.29mg/L、搅拌速度133.8r/min、p H 3.04、温度30.84℃。此时污泥比阻值为4.96×107s2/g。     

安全工程专业实验课研究性教学与创新型人才培养

基于我国高校实验教学现况,阐述对本科专业实验课进行研究性教学改革的必要性和可行性。在论述研究性教学的特征及其在实验教学中优越性基础上,结合安全工程专业的《安全检测技术》实验课的教学改革实践,提出从实验指导书、实验教学大纲、教学方案和考核方式等方面进行全面改革,探讨专业实验课研究性教学中实验设计、实施过程以及对实验环境的要求与改革,提出大力加强开展综合性、设计性及研究创新性实验,并将专业实验课教学与教师科研课题进行有效结合。教改实践表明,在专业实验课中实施研究性教学,有利于实现教学相长、教学与科研相融、人才培养链相接,对培养安全工程创新型人才具有重要意义。     

自然通风下高层建筑条形走廊烟气控制的研究

运用长廊型风洞为实验模型,通过实验与模拟对比的方法,应用FDS软件,模拟研究自然通风下走廊中常见几种烟气控制模式的效果。分析比较各个模式下温度、烟气浓度等的模拟结果得出,在有自然通风下,挡烟垂壁在火灾初期对延缓烟气扩散效果明显,随着火灾的发展,挡烟垂壁几乎没有效果。采用机械排烟后,走廊内温度与烟气浓度均有明显下降,火灾初期走廊内平均温度明显降低,在火灾后期走廊内烟气浓度降低明显。在排烟量不变情况下,采用两个排烟口比单个排烟口排烟效果更好,240s时走廊内CO2浓度相比下降21%。在前室门口设置防烟空气幕可以防止烟气进入前室,利于人员疏散并大幅降低走廊内烟气浓度和温度。开启两个排烟口和挡烟垂壁,结合前室门前设置防烟空气幕,可以达到最好的烟气控制效果,240s时走廊内CO2浓度下降59%,CO浓度下降58%。     

引江入湖修复城市内湖方案的初步探索

文章采用引水换水方案,通过对湖北黄石磁湖水和长江水的水质监测,在实验室条件下,采用静态浸泡实验,模拟换水工程,测定水质基本指标的变化情况,探讨了引江入湖修复城市内湖生态环境方案的可行性。结论认为:采用江水湖水比例为1.5∶1,秋冬季节引水较为适宜;考虑磁湖内源污染严重,单纯的引水对湖水水质改善难以发挥最大的环境和经济效益,可以采取有效的内源污染治理方案和引水方案并重对磁湖进行生态修复。