考虑应力和时间作用的高厨余含量生活垃圾的持水量预测模型:基于试验现象（英文）

Time- and stress-dependent model for predicting moisture retention capacity of high-food-waste-content municipal solid waste:based on experimental evidence

目的:我国城市生活垃圾厨余含量高,导致初始含水量高,从而带来填埋场渗滤液水位高、堆体稳定性低、填埋气难以收集以及焚烧厂焚烧热值低、能耗大等问题。研究降解时间和上覆应力对高厨余垃圾持水量的影响,提出快速降低高厨余垃圾的持水量的方法,大幅减小进场(厂)垃圾的含水量,避免上述问题的发生。创新点:1.获得高厨余垃圾的持水量随降解时间和上覆应力的变化规律;2.建立考虑时间和应力作用的垃圾持水量预测模型。方法:1.通过开展试验,分析高厨余垃圾的持水量随降解时间和上覆应力的变化(图3和5);2.基于试验结果,分析持水量变化机理(图7),并建立持水量预测模型(公式6);3.通过对比分析多种脱水方案的计算结果,提出高厨余垃圾堆体的快速脱水方法(图13)。结论:1.高厨余垃圾的持水量随降解时间呈复合指数形式下降,随应力的对数线性下降;2.降解作用能够降低胞内水并增大孔隙水持有量,应力作用则同时降低胞内水和孔隙水持有量;3.持水量模型计算结果与工程案例实测结果吻合较好,并进一步提出了采取加速降解和增大应力相联合的措施以实现高厨余垃圾快速脱水的目的。

Moisture retention capacity （MRC） is a key parameter for the prediction of leachate production of a municipal solid waste （MSW） pile. In this paper, five sets of laboratory tests were conducted in compression ceils to characterize the variation of MRC with degradation time and overburden stress. Set A was conducted on the fresh high-food-waste-content （HFWC）-MSW under different degradation conditions and a sustained stress; Set B was on the fresh HFWC-MSW by alternation of degradation time and incremental stresses; Sets C, D, and E were on fresh HFWC-MSW, zero-food-waste-content （NFWC）-MSW, and de- composed MSW, respectively, being subjected to incremental stresses. The following findings were obtained from the test re- suits： （1） The MRC of fresh HFWC-MSW decreased exponentially with degradation time under a sustained stress. The higher waste temperature or oxygen introduction would result in a faster declining of MRC. （2） The MRCs decreased linearly with a logarithmic increase of stress for all the MSW samples with different food waste contents. The MRC of HFWC-MSW was higher than that of NFWC-MSW under a given stress, and the decomposed MSW took the second place. （3） The variation of MRC appeared to be independent of stress path in terms of stress and degradation time. Based on the test results, the dependen- cies of the MRC of HFWC-MSW on degradation and stress were interpreted. Then, a time- and stress-dependent model was proposed for predicting the MRC of HFWC-MSW. The model was relatively simple and convenient for design purposes, and was verified by the measured data of leachate production at the pretreatment container of Laogang Incineration Plant. Finally, the model was developed to evaluate the dewatering effect of the HFWC-MSW pile. The strategy of combining the degradation- enhancing measures with stress-increasing measures is recommended in a rapid dewatering project.