It is an important guarantee to enhance the production of coalbed methane （CBM） and reduce the project invest- ment by finding out the drainage feature about CBM wells in different hydrogeological conditions. Based ...It is an important guarantee to enhance the production of coalbed methane （CBM） and reduce the project invest- ment by finding out the drainage feature about CBM wells in different hydrogeological conditions. Based on the CBM explora- tion and development data on the Fanzhuang block in southeast Qinshui Basin and combined with the seepage principle and lithology on the roof and the bottom coalbed, the mathematical model of integrated permeability was established. By perme- ability experiments of the different lithologies on the roof and the floor within the 20 m range combined with the log curves, the integrated permeability of different lithological combinations were obtained. The starting pressure gradient and permeabi- lity of the roof and the floor for different lithologies was tested by ＂differential pressure-flow method＂. The relationships be- tween the starting pressure gradient and the integrated permeability were obtained. The critical distance of limestone water penetrating into coal reservoirs was calculated. According to the drainage feature of CBM wells combined with the drainage data of some CBM wells, the results show that, when limestone water can penetrate into coal reservoirs, the daily water production is high and the daily gas production is low although there is no gas at the beginning of the drainage process, the CBM wells stop discharging water within 6 months after the gas began to come out, and the gas production is steadily improved. When limestone water can not penetrate into coal reservoirs, the daily water production is low and the daily gas production is high at the beginning of the drainage process, and it almost stops discharging water after some time when the gas come out, the daily gas production increases, and the cumulative water production is much lower.展开更多
[Objective] This study was conducted to investigate the effect of laundry wastewater on the quality of river water and the dilution purification effect of river water on laundry wastewater. [Method] The effects of lau...[Objective] This study was conducted to investigate the effect of laundry wastewater on the quality of river water and the dilution purification effect of river water on laundry wastewater. [Method] The effects of laundry wastewater on the contents of total nitrogen(TN), total phosphorus(TP), suspended solids(SS), chemical oxygen demand(COD) and linear alkylbenzene sulfonic acid(LAS) were studied in 7 rivers of Shaoxing City. [Result](1) The contents of TN, TP, SS, COD and LAS increased by 92%, 99%, 340%, 351% and 923%, respectively, at the discharging moment of laundry wastewater; and(2) the five pollutional indexes significantly decreased over time, and especially 2 h after the discharge of laundry wastewater, compared with former the discharge of laundry wastewater, the contents of TN, TP, COD and LAS increased by 6%, 11%, 9% and13%, respectively,while the contents of SS still increased by 76%, i.e., SS required a longer time to achieve self-purification. [Conclusion] Laundry wastewater has some influence on thequality of river water, and the self-purification function of river water could effectively remove pollutants.展开更多
Based on the basic principles of hydrogeology and soil mechanics, studied thegenesis mechanism and control factors of settling of ground surface caused by the drainageof the aquifer in the construction of coal mines, ...Based on the basic principles of hydrogeology and soil mechanics, studied thegenesis mechanism and control factors of settling of ground surface caused by the drainageof the aquifer in the construction of coal mines, and put forward a corresponding calculatingmodel demonstrated by practical example.The study provides mining areas,which are covered with a very thick Quaternary soil layer and abundant ground water, witha theoretical basis aimed at forecasting the settling of ground surface.展开更多
基金Supported by the Major Projects of National Science and Technology Project ＂Development of Coal-bed Gas Dynamic Evaluation Model and Software System＂ （2011ZX05034-005） the National Natural Science Foundation of China （40902044）
文摘It is an important guarantee to enhance the production of coalbed methane （CBM） and reduce the project invest- ment by finding out the drainage feature about CBM wells in different hydrogeological conditions. Based on the CBM explora- tion and development data on the Fanzhuang block in southeast Qinshui Basin and combined with the seepage principle and lithology on the roof and the bottom coalbed, the mathematical model of integrated permeability was established. By perme- ability experiments of the different lithologies on the roof and the floor within the 20 m range combined with the log curves, the integrated permeability of different lithological combinations were obtained. The starting pressure gradient and permeabi- lity of the roof and the floor for different lithologies was tested by ＂differential pressure-flow method＂. The relationships be- tween the starting pressure gradient and the integrated permeability were obtained. The critical distance of limestone water penetrating into coal reservoirs was calculated. According to the drainage feature of CBM wells combined with the drainage data of some CBM wells, the results show that, when limestone water can penetrate into coal reservoirs, the daily water production is high and the daily gas production is low although there is no gas at the beginning of the drainage process, the CBM wells stop discharging water within 6 months after the gas began to come out, and the gas production is steadily improved. When limestone water can not penetrate into coal reservoirs, the daily water production is low and the daily gas production is high at the beginning of the drainage process, and it almost stops discharging water after some time when the gas come out, the daily gas production increases, and the cumulative water production is much lower.
基金Supported by Natural Science Foundation of China(31500321)Scientific Research Foundation of Shaoxing University(20145024)
文摘[Objective] This study was conducted to investigate the effect of laundry wastewater on the quality of river water and the dilution purification effect of river water on laundry wastewater. [Method] The effects of laundry wastewater on the contents of total nitrogen(TN), total phosphorus(TP), suspended solids(SS), chemical oxygen demand(COD) and linear alkylbenzene sulfonic acid(LAS) were studied in 7 rivers of Shaoxing City. [Result](1) The contents of TN, TP, SS, COD and LAS increased by 92%, 99%, 340%, 351% and 923%, respectively, at the discharging moment of laundry wastewater; and(2) the five pollutional indexes significantly decreased over time, and especially 2 h after the discharge of laundry wastewater, compared with former the discharge of laundry wastewater, the contents of TN, TP, COD and LAS increased by 6%, 11%, 9% and13%, respectively,while the contents of SS still increased by 76%, i.e., SS required a longer time to achieve self-purification. [Conclusion] Laundry wastewater has some influence on thequality of river water, and the self-purification function of river water could effectively remove pollutants.
文摘Based on the basic principles of hydrogeology and soil mechanics, studied thegenesis mechanism and control factors of settling of ground surface caused by the drainageof the aquifer in the construction of coal mines, and put forward a corresponding calculatingmodel demonstrated by practical example.The study provides mining areas,which are covered with a very thick Quaternary soil layer and abundant ground water, witha theoretical basis aimed at forecasting the settling of ground surface.
