地浸采铀用聚合物流体控制剂的研究

发布时间：2018-05-15 17:56

本文选题：铀 + 地浸　；参考：《南华大学》2015年硕士论文

【摘要】：我国砂岩铀矿床类型复杂,矿层非均质性严重,孔道分布不均匀。特别是地浸采铀的中后期,大量的注入液沿高渗透矿层突进,致使注入溶浸剂的流动很不均匀,且其不均匀性随注液时间的推移而加剧,导致溶浸剂浓度变低,与矿层接触时间变短,对低渗矿带的浸出率降低,从而整体效率低下。为提高溶浸剂的溶浸范围,改善溶浸效果,消除或减少地下水复原中的不利,对矿层的渗透性及浸出范围进行调整,所采取的一系列工艺技术措施称为流体控制。通过注液井向矿层中注入流体控制剂,其在地层条件下成胶后形成堵塞物,降低高渗透模拟矿层的渗透性,迫使溶浸剂转向进入低渗透层,提高其对低渗透矿层的浸出效果。本课题选用价格较低、使用广泛的低浓度部分水解聚丙烯酰胺和铝系交联剂为材料来合成流体控制剂,较系统全面地对流体控制剂的配方、交联剂的选择及成胶的影响因素进行了研究。通过对流体控制剂的研究,优选出了最佳配方：部分水解聚丙烯酰胺(浓度1～1.5g/L)/柠檬酸铝交联剂(0.3～1%)。随后进行了流体控制剂的影响因素实验,分析了聚合物相对分子质量及浓度、交联剂配比及浓度、矿化度等对凝胶体系成胶性能的影响。还进行了流体控制剂在多孔介质中的流动性实验等。影响因素实验说明,聚合物黏度随聚丙烯酰胺浓度增加而升高；交联体系黏度随交联剂浓度增加而升高；温度越高聚丙烯酰胺溶液和交联体系的黏度越低等。流动性实验说明,流体控制剂优先进入渗透性高的大孔道模拟矿层,而进入低渗层的相对较少；通过对比加入流体控制剂前后水的单位渗流量得出流体控制剂有改变模拟矿层渗透率和使流体转向低渗层的作用,从而达到提高浸出率的目的。
[Abstract]:Sandstone-uranium deposits in China are of complex types, serious heterogeneity and uneven distribution of pores. Especially in the middle and late stage of in-situ leaching of uranium, a large number of injected fluids protrude along the high permeable ore bed, which results in a very uneven flow of the injected solubilizer, and its inhomogeneity is aggravated with the time of injection, resulting in the concentration of the solubilizing agent becoming lower. The contact time with the ore bed becomes shorter and the leaching rate of the low permeability ore belt decreases, thus the overall efficiency is low. In order to improve the leaching range of leaching agent, improve the leaching effect, eliminate or reduce the disadvantage of groundwater restoration, and adjust the permeability and leaching range of ore bed, a series of technical measures are called fluid control. Through the injection of fluid control agent into the ore bed, the fluid control agent is formed after gelatinization under the formation conditions, which reduces the permeability of the high permeability simulated ore bed, forces the leaching agent to turn to the low permeability layer, and improves the leaching effect of the low permeability ore bed. In this paper, the low price, low concentration partially hydrolyzed polyacrylamide and aluminum crosslinking agent were used as the materials to synthesize the fluid control agent, and the formulation of the fluid control agent was systematically and comprehensively. The selection of crosslinking agent and the influencing factors of gelation were studied. Through the study of the fluid control agent, the optimum formula was selected as follows: partially hydrolyzed polyacrylamide (the concentration of 1~1.5g/L)/ aluminum citrate crosslinking agent was 0.3%). The effects of relative molecular weight and concentration of polymer, ratio and concentration of crosslinking agent and salinity on the gelation properties of the gel system were analyzed. The fluidity experiments of fluid control agents in porous media were also carried out. The experimental results show that the viscosity of the polymer increases with the increase of the concentration of polyacrylamide, the viscosity of the crosslinking system increases with the increase of the concentration of crosslinking agent, and the higher the temperature, the lower the viscosity of the solution and crosslinking system. The fluidity experiment shows that the fluid-controlling agent preferentially enters the high-permeability large channel simulated ore bed, while the relatively less fluid control agent enters the low-permeability layer. By comparing the unit seepage flow rate of water before and after the addition of fluid control agent, it is concluded that the fluid control agent can change the permeability of simulated ore bed and make the fluid turn to low permeability layer, thus achieving the purpose of increasing leaching rate.
【学位授予单位】：南华大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD868

【共引文献】