煤矿新型胶结充填材料研发及其性能研究

发布时间：2018-06-28 04:31

本文选题：胶结充填 + 新型胶凝材料　；参考：《中国矿业大学(北京)》2017年博士论文

【摘要】：本文以新阳煤矿高浓度胶结充填技术为基础,充分利用矿区及电厂周边的固体废弃物,在高浓度胶结充填材料的基础上进一步减少水泥的用量,通过实验室试验配制出一种新型胶凝材料,在此基础上优化骨料的颗粒级配,制备出煤矿新型胶结充填材料,对新型胶结充填材料的强度以及输送特性等进行研究。煤矿新型胶结充填材料的开发在提高固体废弃物利用率的同时也为新阳矿充填开采进一步降低充填成本、提高经济效益提供参考。论文通过实验室试验、理论分析、数值模拟和工业试验等手段进行分析与研究,得出以下结论:(1)根据新阳煤矿10203工作面地质条件,并根据胶结充填体早期强度的经验公式以及关键层理论,对充填体早期和后期强度进行理论计算的结果为:为了使采、充工艺能够连贯、顺利进行,并能够有效地控制上覆岩层运移,充填体早期(4h)应保证能够自稳,强度值要求不低于0.16MPa,后期强度(28d)值不低于4MPa。(2)通过实验室试验,对煤矿新型胶凝材料各物料间具体配比以及水化机理研究分析可知:在不掺入激发剂的情况下,煤矿新型胶凝材料的最佳配比为水泥:石灰:脱硫石膏:粉煤灰=20%:1.8%:9%:69.2%。通过激发剂单掺试验得出相同条件下各类型激发剂的激发效果为:Na2SiO3NaOH,Na2SO4CaSO4·2H2O,CaCl2NaCl。选择Na2SiO3、Na2SO4和CaCl2进行复掺试验,通过正交试验法得出三种激发剂的最佳掺量分别为1.0%、1.5%、1.5%,在该激发剂掺量下的新型胶凝材料胶砂试块3d、7d、28d强度值分别为17.20MPa、26.49MPa、42.03MPa,胶凝效果优于高浓度胶凝材料。(3)由XRD衍射能谱可知,煤矿新型胶凝材料起胶凝作用的水化产物为:C-S-H胶凝、钙矾石(AFt)以及水化氯铝酸钙,由于新型胶凝材料掺入各类型激发剂,充分激发粉煤灰活性,使更多粉煤灰参与水化反应,生成更多的胶凝性产物。通过扫描电镜(SEM)对两种胶凝材料的微观结构进行分析可知,当养护龄期为3d时,两者均有C-S-H胶凝(云朵状)和钙矾石(针状)生成,但新型胶凝材料由于激发剂的掺入,针状产物宏观结构上更粗,呈针棒状,且水化产物生成量比高浓度胶凝材料更多,结构更紧密;当养护龄期为7d时,两者的水化产物逐渐增加,CS-H胶凝云朵状颗粒逐渐变大,且空隙减小,但在高浓度胶凝材料中仍可以明显看到未水化的球状粉煤灰颗粒。新型胶凝材料针棒状的钙矾石和水化氯铝酸钙在CS-H胶凝空隙中进一步长大变粗,相互交错使结构进一步密实;当养护龄期为28d时,新型胶凝材料生成大量的C-S-H胶凝呈网状稳定结构,水化产物水化氯铝酸钙进一步发育,呈片状,整体结构更加紧实。对两种胶凝材料的成本进行分析,得出新型胶凝材料成本为127.7元/t,每吨成本比高浓度胶凝材料成本低17.5元,若采用该胶凝材料可大幅度降低充填开采成本。(4)采用单因素法对煤矿新型胶结充填材料的骨料级配、质量浓度以及胶凝材料掺量三个因素进行试验研究,通过对不同条件下新型胶结充填材料的坍落度、泌水率以及各龄期的单轴抗压强度进行测试,其结果为:根据变i法骨料级配理论得出新型胶结充填材料的最佳骨料级配为粒径小于5mm占40%,5~10mm占31%,10~15mm占29%;最佳质量浓度高度及胶凝材料掺量分别为78%和30%。(5)通过新型胶结充填料浆流变试验,并对试验数据分析可知,新型胶结充填料浆属于宾汉塑性体,其流型公式可统一回归为:0?(28)?+η?。通过理论计算、数值模拟和环管试验三种方法所得新型胶结充填料浆沿程阻力损失与局部阻力损失数据相对比,结果相差不超过3%,吻合度很高。数值模拟、理论计算和环管试验均可作为工业输送实践前研究料浆输送特性的方法,为煤矿现场的充填系统设计运转提供理论指导和重要参考。(6)制备新型胶结充填材料进行现场工程实践,充填系统运行稳定,工作面作业顺利,并取得了良好的充填效果。煤矿新型胶结充填料浆输送性能良好,充填体3d、7d、28d强度分别为1.17MPa、2.13MPa、4.92MPa,满足新阳矿充填开采要求。
[Abstract]:Based on the high concentration cemented filling technology in Xinyang coal mine, this paper makes full use of the solid waste around the mining area and the power plant, and further reduces the amount of cement on the basis of high concentration cemented filling material. A new type of cementitious material is prepared through laboratory tests. On this basis, the particle size distribution of aggregate is optimized and a new coal mine is prepared. The strength and transportation characteristics of the new cemented filling materials are studied. The development of new type cemented filling materials for the coal mine is to improve the utilization of solid waste and further reduce the filling cost and improve the economic benefit for the new Yang mine filling mining. The following conclusions are drawn as follows: (1) according to the geological conditions of the 10203 working face of the Xinyang coal mine, and according to the empirical formula of the early strength of the cemented filling body and the theory of the key layer, the results of the theoretical calculation of the early and late strength of the filling body are as follows: in order to make the filling process coherent, It is carried out smoothly and can effectively control overlying strata movement. Early filling body (4h) should be guaranteed to be self stable, the strength value is not less than 0.16MPa, and the later strength (28d) value is not less than 4MPa. (2). Through laboratory test, the specific ratio and hydration mechanism of the new cementitious materials in coal mine are studied and analyzed. Under the circumstances, the best ratio of the new cementitious material for coal mine is cement: Lime: Desulphurization Gypsum: fly ash =20%: 1.8%: 9%: through the single doping test of activator, the excitation effect of various types of activators under the same conditions is: Na2SiO3NaOH, Na2SO4CaSO4. 2H2O, CaCl2NaCl. selection Na2SiO3, Na2SO4 and CaCl2, through the orthogonal test, through orthogonal test. The best dosage of three kinds of activators was 1%, 1.5%, 1.5% respectively. The 3D, 7d and 28d strength values of the new cementitious material were 17.20MPa, 26.49MPa, 42.03MPa respectively under the dosage of the activator, and the cementitious effect was better than that of the high concentration cementitious material. (3) the hydration products of the new cementitious material in coal mine were found to be the hydration products of cementitious action by the XRD diffraction energy spectrum. For C-S-H gelation, ettringite (AFt) and calcium hydrated calcium aluminate, the new cementitious material is mixed with various types of activator and fully activates the activity of fly ash, so that more fly ash participates in the hydration reaction and produces more gelatinization products. The microstructure of two kinds of cementitious materials is analyzed by scanning electron microscope (SEM), when the curing age is 3D Both C-S-H gelation (cloud like) and Ettringite (acicular) are formed in both of them, but the new cementitious material is more coarser in the macro structure of the acicular product because of the addition of the activator, and the formation of hydrated products is more than that of the high concentration cementitious material and the structure is more compact. When the curing age is 7d, the hydration products of both of them are gradually increased and CS-H cementitious. The cloud like particles gradually become larger and the gap decreases, but the unhydrated spherical fly ash particles can still be seen in the high concentration cementitious materials. The new cementitious cementitious materials for the cementitious ettringite and calcium hydrated calcium aluminate further grow thicker in the CS-H cementitious gap and make the structure more dense with each other. When the curing age is 28d, the new cementitious material is new. The type of cementitious material produces a large amount of C-S-H cementitious structure. The hydration product hydrated calcium aluminate calcium is further developed, and the whole structure is more compact. The cost of the two kinds of cementitious materials is analyzed. The cost of the new cementitious material is 127.7 yuan /t, and the cost per ton of cementitious material is 17.5 yuan lower than that of the high concentration cementitious material. If the adhesive is used (4) the single factor method was used to study the aggregate gradation, mass concentration and three factors of cementitious material, by single factor method. The slump, bleeding rate and uniaxial compressive strength of the new cemented filling materials under different conditions were measured. The results are as follows: according to the aggregate gradation theory of variable I method, the best aggregate gradation of the new cemented filling material is 40%, 5~10mm 31% and 10~15mm 29%, and the optimum mass concentration and the content of cementitious material are 78% and 30%. (5) through the rheological test of the new cemented filling slurry, and the new type of test data can be found. The cemented filling slurry belongs to Bingham plastic body, and its flow pattern formula can be uniformly returned to: 0? (28)? + ETA? Through theoretical calculation, numerical simulation and ring tube test have been calculated by comparing the resistance loss of the new cemented filling slurry with the local resistance loss data along the three methods. The results are not more than 3% and the consistency is very high. Numerical simulation, theoretical calculation and Ring tube test can be used as a method to study the conveying characteristics of slurry before industrial transportation. It provides theoretical guidance and important reference for the design and operation of filling system in coal mine. (6) preparation of new cemented filling materials for field engineering practice, stable operation of filling system, smooth working face, and good filling effect. The new type of cemented filling slurry has good conveying performance. The strength of 3D, 7d and 28d of filling body is 1.17MPa, 2.13MPa and 4.92MPa respectively, satisfying the requirements of filling mining in Xinyang mine.
【学位授予单位】：中国矿业大学(北京)
【学位级别】：博士
【学位授予年份】：2017
【分类号】：TD823.7

【参考文献】