煤矸石充填重构土壤水分再分布与剖面气热变化试验研究

发布时间：2018-03-16 10:46

  本文选题：重构土壤　切入点：煤矸石　出处：《水土保持学报》2017年04期 　论文类型：期刊论文

【摘要】：为研究煤矿区用矸石作为垫底基质进行土壤剖面重构土壤水分再分布过程和剖面热扩散与气体浓度变化特征,以指导工程设计和重构土壤熟化技术应用,在实验室设计了一种煤矿区重构土壤水气热运移模拟装置,通过布设在土柱系统不同深度的温湿度传感器和CO_2浓度检测仪,连续监测重构土壤剖面含水量、温度和CO_2浓度。结果表明:煤矸石层具有良好的阻水性,阻碍水分的入渗,增加上层土壤的持水能力。但是,煤矸石的持水性差,煤矸石层的含水量低于土壤层10%左右;煤矸石具有更佳的热扩散性,在加热过程中煤矸石层的温度远大于土壤层,在重构土壤中容易形成稳定的温度梯度,尤其在煤矸石层与土壤层之间存在明显的温度差。土壤层的温度受底部加热的影响较小,短期内主要受室温影响,其变化曲线与室温日变化曲线基本一致,最大波动幅度在2.89℃;底部通CO_2对土壤层CO_2浓度的影响非常小,气体在煤矸石层向土壤层扩散时容易受到土壤层的阻隔,导致气体在土壤层下界面累积;煤矸石层会对邻近土壤层产生较大影响,影响微生物的生存环境,导致微生物的活性下降。当覆土厚度为60cm时,煤矸石层对土壤层的影响较小,随着覆土厚度的增加,煤矸石的影响会逐渐削弱。
[Abstract]:In order to study the process of soil moisture redistribution and the characteristics of heat diffusion and gas concentration change in soil profile reconstruction by using gangue as base substrate in coal mine area, the application of engineering design and reconstruction soil ripening technology was studied in order to guide the engineering design and reconstruction of soil maturation technology. A simulation device for soil moisture and heat transfer in coal mine reconstruction was designed in the laboratory. The moisture content of reconstructed soil profile was continuously monitored by placing a temperature and humidity sensor and a CO_2 concentration detector at different depths of the soil column system. The results of temperature and CO_2 concentration show that the coal gangue layer has good water resistance, hinders the infiltration of water and increases the water holding capacity of the upper soil. However, the water holding capacity of the coal gangue is poor, and the water content of the coal gangue layer is lower than that of the soil layer about 10%; Coal gangue has better thermal diffusivity. The temperature of coal gangue layer is much higher than that of soil layer during heating process, and a stable temperature gradient is easily formed in the reconstruction of soil. Especially, there is a significant temperature difference between the coal gangue layer and the soil layer. The temperature of the soil layer is less affected by the bottom heating, but mainly by the room temperature in the short term, and the variation curve is basically consistent with the diurnal change curve of the room temperature. The maximum fluctuation range is 2.89 鈩，

本文编号：1619586