在环境土工实验室,人工配制新鲜生活垃圾试样,采用大型压缩与直剪联合测定仪器,对288个垃圾试样抗剪强度参数的变化规律进行了研究。将生活垃圾分为3大类,模拟城市经济发展的不发达、发展中及发达3个阶段,将生活垃圾分为3大配比。试验采...在环境土工实验室,人工配制新鲜生活垃圾试样,采用大型压缩与直剪联合测定仪器,对288个垃圾试样抗剪强度参数的变化规律进行了研究。将生活垃圾分为3大类,模拟城市经济发展的不发达、发展中及发达3个阶段,将生活垃圾分为3大配比。试验采用3种初始孔隙比(2.1,2.5,2.9)、4级竖向压力(25,50,100,200 k Pa),每级压力作用下的时间分别为0,0.25,0.5,1,2,6,12,24 h,研究了10种剪应变限值(2%,4%,6%,8%,10%,12%,14%,16%,18%,20%)新鲜垃圾的抗剪强度参数。试验结果表明,新鲜垃圾的抗剪强度与竖向压力可以拟合为一条直线,符合库仑定律。随着剪应变限值的增加,抗剪强度参数c值和φ值均有增加的趋势,符合对数模型。给出了不同因素影响下,新鲜生活垃圾c值和φ值的取值范围,c值在6.14~34.17 k Pa之间、φ值在4.1°~30.6°之间。展开更多
在环境土工实验室人工配制了新鲜生活垃圾,采用大型压缩与直剪联合测定仪器,对96个新鲜垃圾试样进行了压缩变形、剪应力及剪应变联合测定试验,研究了垃圾的压缩变形对强度的影响及规律。试样的初始孔隙比分别为2.1、2.5、2.9,试样竖向...在环境土工实验室人工配制了新鲜生活垃圾,采用大型压缩与直剪联合测定仪器,对96个新鲜垃圾试样进行了压缩变形、剪应力及剪应变联合测定试验,研究了垃圾的压缩变形对强度的影响及规律。试样的初始孔隙比分别为2.1、2.5、2.9,试样竖向压力分别为25、50、100、200 k Pa,每级压力作用下的时间分别为0、0.25、0.5、1、2、6、12、24 h。试验研究表明,(1)不同压缩时间下剪应力与剪应变的关系符合双曲线模型,模型参数a在0.028~0.144之间,参数b在0.012~0.024之间;(2)不同竖向压力及不同剪应变限值下抗剪强度与竖向压缩应变(压缩时间)的关系可以拟合成多项式的形式,得到了参数的拟合值及相关系数,相关系数在0.63~0.98之间;(3)不同初始孔隙比的抗剪强度与竖向压力的关系符合库仑定律,得到了不同剪应变限值的抗剪强度参数,黏聚力在11.1~34.2 k Pa之间,内摩擦角在11.2°~30.6°之间。展开更多
为研究垃圾填埋场渐进堆高过程中垃圾的渗透特性及变化规律,考虑垃圾压缩过程中压力、压缩时间、压缩应变及密度变化等因素的影响,采用自主研发的压缩与渗透联合测定试验仪器,在环境土工实验室,对31个试样180组高有机物含量新鲜生活垃...为研究垃圾填埋场渐进堆高过程中垃圾的渗透特性及变化规律,考虑垃圾压缩过程中压力、压缩时间、压缩应变及密度变化等因素的影响,采用自主研发的压缩与渗透联合测定试验仪器,在环境土工实验室,对31个试样180组高有机物含量新鲜生活垃圾进行系统的室内试验研究。压缩试验过程采用6级压力(0,25,50,100,200,300 k Pa),每级压力采用6个不同的压缩时间(0,1,2,6,12,24 h);渗透试验过程考虑6个水力梯度。试验结果表明:(1)存在临界水力梯度,只有当水力梯度超过临界水力梯度后,垃圾才会发生渗流。(2)渗透速率与水力梯度的关系可拟合为一条直线,符合达西渗透定律;(3)渗透速率与压力的关系可以拟合为指数函数,拟合系数大于0.93;(4)渗透系数的对数与密度的关系可以拟合为一条直线,拟合系数大于0.98,给出了直线关系表达式;(5)渗透系数的对数与压缩应变的关系也可拟合为一条直线,拟合系数大于0.97,给出了直线方程。试验结果可为垃圾填埋场的渗透性分析提供参考。展开更多
An expanded granular sludge bed (EGSB) reactor inoculated with anaerobic granular sludge was started up with its COD removal performance, self-balancing of pH, biogas production rate and characteristics of the granu...An expanded granular sludge bed (EGSB) reactor inoculated with anaerobic granular sludge was started up with its COD removal performance, self-balancing of pH, biogas production rate and characteristics of the granular sludge during the start-up period being investigated. The results indicated that the EGSB reactor can be started up successfully in 27 d by increasing the organic loading rate rapidly. The removal efficiency of COD was maintained above 93% with influent COD concentration of 25 000 mg/L and OLR of 37.94 kgCOD/(m 3 ·d). The EGSB reactor with good pH self-balancing could be fed with fresh leachate of low pH value (4 5). The biogas production rate was closely related with OLR and COD reduction. Every gram of COD fed (consumed) to the reactor produced 0.34 L STP (0.36 L STP ) biogas with 0.21 L STP (0.23 L STP ) methane. Thus, 65% 70% of the produced biogas was methane. Sixty one percentage of COD fed to the reactor was converted to methane, another 33% was converted to biomass by metabolism, and the other 6% was left in the liquid phase. The specific methanogenic activity (SMA) of the granular sludge had increased by 92% after 27 d dynamic incubation. The granular sludge in the reactor had good settlement performance with majority diameter of 1 2 mm.展开更多
文摘在环境土工实验室,人工配制新鲜生活垃圾试样,采用大型压缩与直剪联合测定仪器,对288个垃圾试样抗剪强度参数的变化规律进行了研究。将生活垃圾分为3大类,模拟城市经济发展的不发达、发展中及发达3个阶段,将生活垃圾分为3大配比。试验采用3种初始孔隙比(2.1,2.5,2.9)、4级竖向压力(25,50,100,200 k Pa),每级压力作用下的时间分别为0,0.25,0.5,1,2,6,12,24 h,研究了10种剪应变限值(2%,4%,6%,8%,10%,12%,14%,16%,18%,20%)新鲜垃圾的抗剪强度参数。试验结果表明,新鲜垃圾的抗剪强度与竖向压力可以拟合为一条直线,符合库仑定律。随着剪应变限值的增加,抗剪强度参数c值和φ值均有增加的趋势,符合对数模型。给出了不同因素影响下,新鲜生活垃圾c值和φ值的取值范围,c值在6.14~34.17 k Pa之间、φ值在4.1°~30.6°之间。
文摘在环境土工实验室人工配制了新鲜生活垃圾,采用大型压缩与直剪联合测定仪器,对96个新鲜垃圾试样进行了压缩变形、剪应力及剪应变联合测定试验,研究了垃圾的压缩变形对强度的影响及规律。试样的初始孔隙比分别为2.1、2.5、2.9,试样竖向压力分别为25、50、100、200 k Pa,每级压力作用下的时间分别为0、0.25、0.5、1、2、6、12、24 h。试验研究表明,(1)不同压缩时间下剪应力与剪应变的关系符合双曲线模型,模型参数a在0.028~0.144之间,参数b在0.012~0.024之间;(2)不同竖向压力及不同剪应变限值下抗剪强度与竖向压缩应变(压缩时间)的关系可以拟合成多项式的形式,得到了参数的拟合值及相关系数,相关系数在0.63~0.98之间;(3)不同初始孔隙比的抗剪强度与竖向压力的关系符合库仑定律,得到了不同剪应变限值的抗剪强度参数,黏聚力在11.1~34.2 k Pa之间,内摩擦角在11.2°~30.6°之间。
文摘为研究垃圾填埋场渐进堆高过程中垃圾的渗透特性及变化规律,考虑垃圾压缩过程中压力、压缩时间、压缩应变及密度变化等因素的影响,采用自主研发的压缩与渗透联合测定试验仪器,在环境土工实验室,对31个试样180组高有机物含量新鲜生活垃圾进行系统的室内试验研究。压缩试验过程采用6级压力(0,25,50,100,200,300 k Pa),每级压力采用6个不同的压缩时间(0,1,2,6,12,24 h);渗透试验过程考虑6个水力梯度。试验结果表明:(1)存在临界水力梯度,只有当水力梯度超过临界水力梯度后,垃圾才会发生渗流。(2)渗透速率与水力梯度的关系可拟合为一条直线,符合达西渗透定律;(3)渗透速率与压力的关系可以拟合为指数函数,拟合系数大于0.93;(4)渗透系数的对数与密度的关系可以拟合为一条直线,拟合系数大于0.98,给出了直线关系表达式;(5)渗透系数的对数与压缩应变的关系也可拟合为一条直线,拟合系数大于0.97,给出了直线方程。试验结果可为垃圾填埋场的渗透性分析提供参考。
基金supported by the Science and Technology Commission of Shanghai Municipality (Grant Nos.10DZ120010C,D9DZ2251700)
文摘An expanded granular sludge bed (EGSB) reactor inoculated with anaerobic granular sludge was started up with its COD removal performance, self-balancing of pH, biogas production rate and characteristics of the granular sludge during the start-up period being investigated. The results indicated that the EGSB reactor can be started up successfully in 27 d by increasing the organic loading rate rapidly. The removal efficiency of COD was maintained above 93% with influent COD concentration of 25 000 mg/L and OLR of 37.94 kgCOD/(m 3 ·d). The EGSB reactor with good pH self-balancing could be fed with fresh leachate of low pH value (4 5). The biogas production rate was closely related with OLR and COD reduction. Every gram of COD fed (consumed) to the reactor produced 0.34 L STP (0.36 L STP ) biogas with 0.21 L STP (0.23 L STP ) methane. Thus, 65% 70% of the produced biogas was methane. Sixty one percentage of COD fed to the reactor was converted to methane, another 33% was converted to biomass by metabolism, and the other 6% was left in the liquid phase. The specific methanogenic activity (SMA) of the granular sludge had increased by 92% after 27 d dynamic incubation. The granular sludge in the reactor had good settlement performance with majority diameter of 1 2 mm.