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191.
本文以贵州发耳煤矿10102采煤工作面作为研究对象,对采空区高位钻孔抽放瓦斯原理进行论述,并且结合此原理设计高位钻孔的抽放参数。为有效快捷地评价高位钻孔的抽放效果,本文通过单元法对其进行评价,最终找到存在的问题及其解决方法。该技术的应用实践解决了该工作面瓦斯超限的问题,获得了有价值的技术参数,积累了宝贵的实践经验。  相似文献   
192.
The highest removal efficiencies of COD and TN were achieved under 10 mg/L of Al3+. The highest TP removal efficiency occurred under 30 mg/L of Al3+. EPS, PS and PN concentrations increased with the addition of Al3+. Sludge properties significantly changed with the addition of Al3+. Aluminum ions produced by aluminum mining, electrolytic industry and aluminum-based coagulants can enter wastewater treatment plants and interact with activated sludge. They can subsequently contribute to the removal of suspended solids and affect activated sludge flocculation, as well as nitrogen and phosphorus removal. In this study, the effects of Al3+ on pollutant removal, sludge flocculation and the composition and structure of extracellular polymeric substances (EPS) were investigated under anaerobic, anoxic and oxic conditions. Results demonstrated that the highest chemical oxygen demand (COD) and total nitrogen (TN) removal efficiencies were detected for an Al3+ concentration of 10 mg/L. In addition, the maximal dehydrogenase activity and sludge flocculation were also observed at this level of Al3+. The highest removal efficiency of total phosphorus (TP) was achieved at an Al3+ concentration of 30 mg/L. The flocculability of sludge in the anoxic zone was consistently higher than that in the anaerobic and oxic zones. The addition of Al3+ promoted the secretion of EPS. Tryptophan-like fluorescence peaks were detected in each EPS layer in the absence of Al3+. At the Al3+ concentration of 10 mg/L, fulvic acid and tryptophan fluorescence peaks began to appear, while the majority of protein species and the highest microbial activity were also detected. Low Al3+ concentrations (<10 mg/L) could promote the removal efficiencies of COD and TN, yet excessive Al3+ levels (>10 mg/L) weakened microbial activity. Higher Al3+ concentrations (>30 mg/L) also inhibited the release of phosphorus in the anaerobic zone by reacting with PO43-.  相似文献   
193.
关振东  杨君 《安全》2005,26(5):51-51,53
煤炭企业的一切生产经营活动,都离不开"人"这个第一要素,而煤炭企业的发展是依赖生产的发展才能够体现其先进生产力的要素,一是先进的技术、设备、工艺;二是具有较高文化水平,能够熟悉设备性能,掌握操作技能,生产出优质产品和做到文明生产的作业工人.  相似文献   
194.
Environmental Fluid Mechanics - Vegetation in watercourses can influence different aspects of flow structure, subsequently affecting many processes of flow, such as pollutant transportation,...  相似文献   
195.
Aged municipal solid wastes (MSW) excavated from landfills and dumpsites were characterized to analyze their fraction composition, moisture content, and lower heat value (LHV). The necessity and feasibility of recycling combustibles from aged MSW to improve the incineration of fresh MSW were investigated. The results showed that combustibles in aged MSW were easily separated from other components and than LHV of the separated combustibles are higher than 11000 kJ/kg. The fresh MSW are of high moisture contents with average LHV below 6500 kJ/kg, making their stable combustion difficult to maintain in MSW incinerators. For both fresh MSW and aged MSW, plastics are the main contributor to their LHV. To improve incineration of fresh MSW that are characterized with low LHV, combustibles separated from aged MSW were made into refuse derived fuel (RDF) pellets and were then added to fresh MSW by 2% wt.–5% wt. LHV variation and air supply resistance change of the MSW layer on the incinerator grate caused by the addition of RDF was checked, and no significant changes were found. No obvious difference was observed for the ‘burn-out time’ between RDF pellets and fresh MSW either. RDF made from aged MSW combustibles is found to be a promising auxiliary fuel to improve the incineration of fresh MSW, and aged MSW from old landfill cells and dumpsites can be finally disposed of jointly with fresh MSW by recycling combustible from the former to be coincinerated with the latter in the incineration plants.  相似文献   
196.
低浓度生活污水处理工艺调试运行   总被引:1,自引:0,他引:1  
介绍了绩溪污水处理厂在低浓度进水条件下的生物启动和调试运行,通过外加碳源虽然可以暂时缓解培养初期活性污泥增长缓慢的问题,但不是长期的运行方式。可以引入部分工业废水至生物处理系统,以提高进水有机底物浓度。但要特别注意避免冲击负荷对系统带来的破坏性影响,同时应根据实际情况灵活调整工艺参数。  相似文献   
197.
菲高效降解菌的降解特性及其受蒙脱石的影响研究   总被引:1,自引:0,他引:1  
通过选择性富集培养与纯化,从广州油制气厂附近的污染土壤中分离获得一株能以菲为唯一碳源和能源,快速生长的优势菌株(编号为YZ-1)。16S rDNA序列分析结果表明,YZ-1菌株为琼氏不动杆菌(Acinetobacter junii)。当无机盐培养液中菲初始质量浓度为100mg·L-1时,45h内该菌株对菲的降解率可达到99.5%。YZ-1菌株的最佳生长条件为pH7.4,温度30℃,摇床转速160r·min-1。加入蒙脱石矿物之后,在降解的初期(前16h)表现为促进菲的生物降解作用,但随着时间的延长,菲的降解速率逐渐低于不加蒙脱石体系,并随蒙脱石含量或菲质量浓度的增加,此抑制延缓现象愈加明显。矿物对高浓度的菲具有吸附分散作用,而对低浓度的菲具有吸附保护作用。  相似文献   
198.
复极性固定床电解反应器对活性染料的降解   总被引:11,自引:0,他引:11  
管玉江  杨卫身 《环境化学》1999,18(3):270-273
本文用复极性固定床电解反应器对16种活性染料的脱色降解进行了试验研究。结果表明:染料脱色率在99.6%以上,出水上清液COD去除率绝大部分在90%以上,对活性翠蓝KN-G和活性深蓝KM-GR的铜去除率分别为97.0%和99.7%。  相似文献   
199.
采用生物制剂 (BS7# 酶 )洗涤法处理冀东油田作业井场固体废弃物 ,研究了该处理方法中制剂投加量、搅拌时间、固液比和洗涤次数对处理效果的影响 ,得到了最佳洗涤条件。并对其设备投资、处理综合成本等进行了经济效益分析。为冀东油田作业井场含油固体废弃物工业化处理提供重要依据  相似文献   
200.
Functional Properties of Extruded Acetylated Starch-Cellulose Foams   总被引:2,自引:0,他引:2  
Acetylated starches, with degrees of substitution (DS) of 2, 2.5 and 3, were blended with 3%, 7.5% and 12% -cellulose and 14%, 17% or 20% (d.b.) ethanol and twin-screw extruded at 165°C barrel temperature and 225 rpm screw speed. A response surface methodology experimental design was applied to the sub-plot and a completely randomized design to the whole plot design to test the differences among the acetylated starches and the effects of cellulose and ethanol. DS, cellulose and ethanol contents significantly affected the functional properties and specific mechanical energy requirement. DS had positive effects on radial expansion ratio (RER), compressibility and specific mechanical energy requirement and a negative effect on bulk density. Highest (RER) was obtained from 20% ethanol content. Extrudates containing 12% cellulose had the highest bulk density and the highest compressibility. Higher cellulose contents required more specific mechanical energy.  相似文献   
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