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Coal and gas outburst prevention using new high water content cement slurry for injection into the coal seam

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International Journal of Mining Science and Technology 2017年第4期27卷 669-673页

作者： Zhou Peiling Zhang Yinghua Huang Zhi'an Gao Yukun Wang Hui Luo Qiang State Key Laboratory of High-Efficient Mining and Safety of Metal Mines University of Science and Technology Beijing Ministry of Education

As coal and gas outburst is one of the most serious mine disasters, it is very important to at least control it if not prevent it from occurring. Injecting cement slurry or grouting into the coal seam can strengthen the seam, increase its rigidity coefficient(f), and reduce the volumetric expansion due to gas energy release.This paper reports the results of laboratory experiments on cement-based high water content slurry having different water-cement ratios(W/C) to be used for coal injection. The results show that as the W/C increases, the mobility of the slurry and its setting time increase. The compressive strength and rupture strength, however, are reduced. Furthermore, high W/C grout shows early strength after 7 days, which can be 80% of its 14-day compressive strength. To achieve rapid setting and early strength, the addition of Na_2SiO_3has proven to give the best result, when the concentration of the additive is 3%. The initial and final setting times are 13 and 21 min shorter than samples without Na_2SiO_3, while the compressive strength is more than double. As a retarder, the initial setting time can be extended to 83 min when tartaric acid of 0.4% concentration is added. Through the orthogonal experiment, the optimum recipe of the new high water content slurry has been determined to be: W/C = 2, tartaric acid = 0.2%, Na_2SiO_3= 3%, and12% bentonite. Reinforcement by injection simulation experiments show that the grouting radius of the new slurry mix is 250 mm when the applied grouting pressure is 60 k Pa, 7-day rupture strength and compressive strength are 5.2 and 6.4 MPa, respectively, and are 37% and 88% higher than ordinary cement grout. It can be concluded that the newly developed slurry mix is more effective than the ordinary mix for reinforcing coal and controlling gas outburst.

关键词： Gas outburst Setting liquid Reinforce coal High-water solidified materials Rapid setting and early strength cement retarder

辨析s'attarder,retarder和tarder

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法语学习 2004年第6期 54-56页

作者：傅荣北京外国语大学法语系

从词源上看，S’attarder，retarder和tarder一脉相承，并且各自的中心含义都与“迟，延迟，耽搁”相关。不过，在实际运用中却有一定讲究，值得加以辨析。

关键词： s'attarder retarder tarder 词源法语词语辨析代动词

液力缓速器：引领商用汽车安全潮流——斯堪尼亚液力缓速器(retarder)的卓越功效

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物流技术与应用(货运车辆) 2007年第1期 70-71页

作者：周擎阳

作为卡车主人(司机)的您在车辆日常使用和保养的过程中,一定会为经常更换刹车片而烦恼,因为这将造成您运输成本的增加和出车时间的减少。目前国内绝大多数重型车辆的制动系统主要依靠轮毂制动,如果车辆在长时间高速行驶或者超载行驶的... 详细信息

作为卡车主人(司机)的您在车辆日常使用和保养的过程中,一定会为经常更换刹车片而烦恼,因为这将造成您运输成本的增加和出车时间的减少。目前国内绝大多数重型车辆的制动系统主要依靠轮毂制动,如果车辆在长时间高速行驶或者超载行驶的情况下,频繁地制动势必大大加快刹车片的磨损,增加制动衬片热衰退的可能。另外,在长途运输驾驶过程中,频繁踩踏制动踏板也会增加司机的疲劳度,影响车辆的行车安全。瑞典斯堪尼亚公司长期致力于研发能够最大程度减少营运总成本的车辆,在制动系统方面,除了高效的轮毂制动外,一系列的辅助制动系统也是斯堪尼亚开发

关键词：液力缓速器 retarder 辅助制动系统斯堪尼亚

Flow and Flow Decay of Refractory Castables

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China's Refractories 2003年第4期12卷 16-19页

作者： CHENZhiqiang BjomMyhre BjornSandberg ElkemInternationalTrade（Shanghai）Co. Ltd ElkemRefractoriesP.O.Box8126 N-4602KristiansandNorway

Installation of refractory castables depend not only on flow , but also on how soon the flow is lost because of setting. The loss of flow (flow decay) has always been one of the main problems of refractory castable manufacturers , a problem that has not been too well described in literature . The flow decay has been studied for a castable system based on alumina , pointing out some general trends . The flow decay was found very temperature sensitive, being strongly accelerated by temperature increases. To compensate for excessive flow loss, a retarder like citric acid may be used. Thus flow decay was measured as a function of citric acid ( retarder) addition at 35℃.

关键词： Refractory Flow Flow decay Alumina based castable retarder Setting time

Investigation of the Transition Reaction of Tobermorite to Xonotlite under Influence of Additives

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Advances in Chemical Engineering and Science 2015年第2期5卷 197-214页

作者： Andrea Hartmann David Schulenberg Josef-Christian Buhl Institute of Mineralogy Hannover University Hannover Germany

The objective of the present work was to investigate the transition reaction of the calcium silicate hydrate tobermorite into xonotlite under influence of additives. Tobermorite is the main binding agent in steam hardened building materials and the appearance of xonotlite indicates the progress of hardening and an overcuring of the material. Hydrothermal experiments under addition of sucrose, calcium formate and calcium chloride dihydrate to the main components quartz and lime were done using temperatures of 220°C and a reaction time of 40.5 h. All experiments were performed with powders as well as with pressed educts. The products of all syntheses were analyzed with XRD, SEM/EDX and FTIR. The references as well as the syntheses with calcium chloride dihydrate led to the formation of 11 Å tobermorite and xonotlite. The former showed the best results and even synthesis with pressed educts and calcium chloride dihydrate revealed an accelerating effect of the additive. In contrast syntheses with sucrose had the worst reactivity and led to the formation of calcite beside the CSH-phase scawtite. The additive calcium formate was only slightly oppressing the crystallization of tobermorite and favouring the formation of xonotlite. Syntheses with pressed pellets and sucrose or calcium formate showed generally worse results.

关键词： CSH-Phases Tobermorite Xonotlite Additives retarder Accelerator

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石油与天然气化工 2012年第3期41卷 357-362页

The article presents abstracts of papers on chemical engineering of oil and gas, including a traceable calibration procedure for hydrocarbon dew point chilled mirror instruments and research direction and challenges f... 详细信息

关键词： acidizing air oxidation amine value ammonia or ammonium salt analysis anti-swelling agent anti-swelling performance anti-swelling rate anticorrosion coating ASP produced water average particle size bimodal calibration casing--damaged well catalyst cement chimney clay minerals CO2 comparison research complex gas components core damage corrosion inhibitor CPS crude sewage desulphurization determination diversion ejector energy development energy efficiency benchmarking evaluation FCC foam drainage foam mass foam stabilizer foamed acid foaming agent function design Gas field gathering pipelines H2S high temperature high-sulfur hydrocarbon dew point hydrocarbon dew point chilled mirror instruments incinerator inspection integrated equipment kinetic hydrateinhibitors LaFeO3 liquefied petroleum gas dispenser liquid loading load low permeability and low pressure LPG mechanical strength methane methane hydrates metrological verification microbial flocculant multifunctional activated acid natural gas natural gas desulfurization natural gas hydrate network management platform new technology offshore oilfield oil yield oilfield application operation operation points parameter optimization performance evaluation perovskite oxide compound plugging plugging causes analysis polymer polymer-surfactant displacement pore distribution prevention measures removal rate of solid suspensions replacement rate response of performance retarder rotating-strip-port round-port scale inhibitor scaling screening silica gel slight expansion SO2 solid-liquid separation treatment solubilization sour gas field sulfur recovery system construction tail gas treatment hydro-treating heater technical summary thermodynamics titration method traceability transport pipeline treatment technology uncertainty of measurement viscosity waste drilling fluid water content water injection water producing water sensitivity damage water-sensitivity