煤矸石资源充分利用的新工艺

从煤矸石中提取氧化铝，并用残渣直接煅烧硅酸盐水泥熟料，同时作废气、废液循环，是煤矸石资源开发利用的新工艺。通过对工艺原理的研究，揭示了煤矸石-石灰石-纯碱烧结过程的反应历程及影响氧化铝提取率的因素，分析了残渣直接煅烧水泥熟料的机理和废气、废液循环利用的可能性，实现了资源的合理利用。     

煤矸石－粉煤灰－废石膏烧结陶粒

采用制粒烧结工艺成功地把煤矸石、粉煤灰及废石膏（或烟气脱硫污泥）制备成建筑用轻质陶粒，实现了对上述固体废物的资源化和稳定化。煤矸石等的配料比以及粉状原料的颗粒尺寸分布是在成球盘中制粒的主要影响因素。烧结过程中的影响因素较多，但烧结温度是影响产品质量的主要因素。煤矸石－粉煤灰－废石膏陶粒烧结过程发生在９５０—１２５０℃，最佳烧结温度为１２００±５０℃，制得的陶位坚硬如岩石，容重等级为９００，筒压强度为９—１５ＭＰａ，超过ＧＢ２８３８－８１的筒压强度≥６．５ＭＰａ的规定。     

煤矸石,粉煤灰与风化页岩综合利用

阐述了以挤出成型的方法综合利用煤矸石、粉煤灰和风化页岩生产烧结多孔砖的工艺过程．通过试验，对成型工艺、半成品的干燥过程，烧结阶段升温速度及烧成温度进行了详细的探讨，并确定了最佳的工艺参数     

从煤矸石中提取氧化铝并用残渣直接煅烧水泥的工艺研究

从煤矸石中提取氧化铝，废气和废液作封闭循环，并用残渣直接煅烧硅酸盐水泥熟料，是煤矸石高附加值，低污染的综合利用新工艺。本文通过对其工艺过程和产品性能的描述，确定了氧化铝提取率与其单位成本和残渣组成的关系，揭示了残渣中几种主要组成对煅烧工艺的影响，并对废气循环和溶液碳化分解的ｐＨ值问题进行了分析。     

淮南选矸电解生产Al-Si-Ti合金的研究

对淮南煤矸石低温焙烧酸浸脱杂并电解生产ＡｌＳｉＴｉ合金进行了研究．结果表明，采用该工艺生产ＡｌＳｉＴｉ合金切实可行，关键在煤矸石中杂质的脱除，焙烧温度是影响脱杂的主要因素，在３００—４５０℃之间能取得最佳脱杂效果，其杂质总量由１０％左右降低到１５％以下；脱杂煤矸石在温度为１０００℃左右、阴阳极电流密度分别为０７和１０Ａ／ｃｍ２电解条件下能被还原并共同沉积形成合金，所得合金化学组成符合国家标准相应牌号合金的要求．     

煤矸石－粉煤灰－废石膏烧结陶粒

采用制粒烧结工艺成功地把煤矸石、粉煤灰及废石膏(或烟气脱硫污泥)制备成建筑用轻质陶粒,实现了对上述固体废物的资源化和稳定化。煤矸石等的配料比以及粉状原料的颗粒尺寸分布是在成球盘中制粒的主要影响因素。烧结过程中的影响因素较多,但烧结温度是影响产品质量的主要因素。煤矸石-粉煤灰-废石膏陶粒烧结过程发生在950—1250℃,最佳烧结温度为1200±50℃,制得的陶位坚硬如岩石,容重等级为900,筒压强度为9—15MPa,超过GB2838-81的筒压强度≥6.5MPa的规定。     

金属化合物对煤矸石燃烧动力学特性的影响

采用非等温热重分析法研究金属化合物对煤矸石燃烧动力学过程的影响，提出煤矸石挥发分析出过程的特性参数和反应动力学方程，并测算了反映煤矸石燃烧放热特性的差热峰面积指标．结果表明，掺加金属化合物可以降低煤矸石挥发分的初析温度，提高煤矸石的燃烧放热量和燃烬水平．     

煤矸石酸浸制备水玻璃工艺中参数条件对SiO2溶出率影响研究

在常压条件下,煤矸石通过酸浸分离氧化铝后,酸浸残渣可作为制备水玻璃原料.研究了不同酸浸液浓度、浸提温度、浸提时间对煤矸石中SiO2溶出率的影响,溶出率越高反映煤矸石制备水玻璃的原料利用率越高,并以正交试验和极差结果进行了因素分析.结果表明:硫酸酸浸工艺的主要影响因素为酸浸液浓度,最佳工艺参数组合为酸浸液浓度为0.7 m...     

BF4-废水水解法实验

常温下用水解法处理ＢＦ４废水．实验采用铝盐作主水解剂，试剂Ａ作助水解剂，ｐＨ值小于３，在常温条件下实现了对ＢＦ４的高效水解．研究结果表明，ＢＦ４∶Ａｌ３＋∶Ａ的质量比为１∶０．８∶０．１，水解时间６～３ｈ，水解率达到９９．５％以上．使用助水解剂Ａ，缩短了水解时间，减少了铝盐用量，对高浓度的ＢＦ４废水效果尤为显著，水解时间可缩短一半，主水解剂用量可减少１／５，处理后出水中的ＢＦ４含量可降到１０ｍｇ／Ｌ以下．     

电解锰渣-页岩-粉煤灰烧结砖的研制

针对湖南湘潭竹埠港地区工业废渣的情况,进行了电解锰渣-页岩-粉煤灰体系烧结制砖的研制.确定了配比、烧结温度和保温时间对烧结砖性能的影响,通过SEM、EDS、抗压强度、毒性浸出、DTA和XRD等检测手段,对烧结前后砖体的结构及各项性能进行了检验.结果显示,电解锰渣、页岩和粉煤灰的配比为4:5:1、烧结温度为1000℃'保...     

Toxic effects of acetochlor, methamidophos and their combination on nifH gene in soil

Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis （DGGE） and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity （both in gene richness and diversity index values） and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor （50 mg/kg） recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos （150 mg/kg） caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos （250 mg/kg） produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes （bands） responded differently to the impact of agrochemicals： four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.     

Arsenic uptake by arbuscular mycorrhizal maize （Zea mays L.） grown in an arsenic-contaminated soil with added phosphorus

The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.     

Impact of atrazine and nitrogen fertilizers on the sorption of chlorotoluron in soil and model sorbents

Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter.     

Degradation of metabolites accumulated of benzo[a]pyrene by coupling Penicillium Chrysogenum with KMnO4

Several main metabolites of benzo[a]pyrene （BaP） formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone （BP 1,6- quinone）, trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene （BP 7,8-diol）, 3-hydroxybenzo[a]pyrene （3-OHBP）, were identified by high-performance liquid chromatography （HPLC）. The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that （1） the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; （2） the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; （3） the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% （w/v）, concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.     

Potential of plant polyphenol oxidases in the decolorization and removal of textile and non-textile dyes

In this study an effort has been made to use plant polyphenol oxidases; potato （Solanum tuberosum） and brinjal （Solanum melongena）, for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.     

Effects of two sludge application on fractionation and phytotoxicity of zinc and copper in the soil

The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and their phytotoxicity to pakchoi. The loamy soil was mixed with 0%, 20%, 40%, 60% and 80% (by weight) of digested sewage sludge (SS) and composted sludge (SC). The additions of both sludges caused a significant raise in all fractions, resulting in that exchangeable (EXCH) and organic bound (OM) became predominance of Zn and organic bound Cu occupied the largest portion. There was more available amount of Zn and Cu in SS treatments than SC treatments. During the pot experiment, the concentration of Zn in EXCH, carbonate (CAR) and OM and Cu in EXCH and OM fractions decreased in all treatments, so their bioavailability reduced. Germination rate and plant biomass decreased when the addition rate was high and the best yield appeared in 20% mixtures at the harvest of pakchoi. The two sludges increased tissue contents of Zn and Cu especially in the SS treatments. Zn in pakchoi was not only in relationship to ΔEXCH and ΔCAR forms but also in ΔOM forms in the sludge-soil mixtures. Tissue content of Cu in pakchoi grown on SC-soils could not be predicted by ΔEXCH. These correlation rates between Zn and Cu accumulation in pakchoi and variation of different fractions increased with time, which might indicate that sludges represented stronger impacts on the plant in long-term land application.     

Intraspecific differences in effects of co-contamination of cadmium and

A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium (Cd)(0-10 mg/L) and arsenate (As(V)) (0-8 mg/L) on the growth parameters and accumulation of Cd and As in six wheat varieties Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongmai-8. The endpoints of wheat seedlings, including seed germination,biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties (p ＜ 0.05). The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11,Jing-411, Jingdong-8 and Zhongmai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongmai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.     

Removal of heavy metals from sewage sludge by low costing chemical method and recycling in agriculture

ＲｅｍｏｖａｌｏｆｈｅａｖｙｍｅｔａｌｓｆｒｏｍｓｅｗａｇｅｓｌｕｄｇｅｂｙｌｏｗｃｏｓｔｉｎｇｃｈｅｍｉｃａｌｍｅｔｈｏｄａｎｄｒｅｃｙｃｌｉｎｇｉｎａｇｒｉｃｕｌｔｕｒｅＷｕＱｉｔａｎｇ，ＮｙｉｒａｎｄｅｇｅＰａｓｃａｓｉｅ，ＭｏＣｅｈｕｉＦ...     

Isolation and preliminary characterization of a 3-chlorobenzoate degrading bacteria

A study was conducted to compare the diversity of 2-, 3-, and 4-chlorobenzoate degraders in two pristine soils and one contaminated sewage sludge. These samples contained strikingly different populations of mono-chlorobenzoate degraders. Although fewer cultures were isolated in the uncontaminated soils than contaminated one, the ability of microbial populations to mineralize chlorobenzoate was widespread. The 3- and 4-chlorobenzoate degraders were more diverse than the 2-chlorobenzoate degraders. One of the strains isolated from the sewage sludge was obtained. Based on its phenotype, chemotaxonomic properties and 16S rRNA gene, the organism S-7 was classified as Rhodococcus erythropolis. The strain can grow at temperature from 4 to 37℃. It can utilize several （halo）aromatic compounds. Moreover, strain S-7 can grow and use 3-chlorobenzoate as sole carbon source in a temperatures range of 10-30℃ with stoichiometric release of chloride ions. The psychrotolerant ability was significant for bioremediation in low temperature regions. Catechol and chlorocatechol 1,2-dioxygenase activities were present in cell free extracts of the strain, but no （chloro）catechol 2,3- dioxygenase activities was detected. Spectral conversion assays with extracts from R. erythropolis S-7 showed accumulation of a compound with a similar UV spectrum as chloro-cis,cis-muconate from 3-chlorobenzoate. On the basis of these results, we proposed that S-7 degraded 3-chlorobenzoate through the modified ortho-cleave pathway.     

Single and joint effects of pesticides and mercury on soil urease

The influence of two pesticides including chlorimuron-ethyl and furadan and mercury （Hg） on urease activity in 4 soils （meadow burozem and phaeozem） was investigated. The soils were exposed to various concentrations of the two pesticides and Hg individually and simultaneously. Results showed that there was a close relationship between urease activity and organic matter content in soil. Chlorimuron-ethyl and furadan could both activate urease in the 4 soils. The maximum increment of urease activity by chlorimuronethyl was up to 14%-18%. There was almost an equal increase （up to 13%-21%） in the urease activity by furadan. On the contrary, Hg markedly inhibited soil urease activity. A logarithmic equation was used to describe the relationship （P〈0.05） between the concentration of Hg and the activity of soil urease in the 4 tested soils. Semi-effect dose （ED50） values by the stress of Hg based on the inhibition of soil urease in the 4 soils were 88, 5.5, 24 and 20 mg/kg, respectively, according to the calculation of the corresponding equations. The interactive effect of chlorimuron-ethyl or furadan with metal Hg on soil urease was mainly synergic at the highest tested concentrations.