Effect of gas pressure on municipal solid waste landfill slope stability

Slope failure in municipal solid waste (MSW) landfills is a common environmental disaster that poses serious ecological and health risks. Landfill slope stability (SS) is sensitive to leachate levels and gas pressure (GP) caused by the degradation of organic material, but the extent of these combined effects remains poorly understood. In this study, a simplified landfill GP calculation method is presented and a circular slide method that considers the combined effects of leachate and GP is established. The results show that the landfill GP is mainly affected by the gas production rate, gas conductivity of the solid waste (SW), and landfill depth. The safety factor of landfill SS is also significantly lower when GP is considered. The distribution of GP is affected by the depth of the failure circle and SW. Landfill slope instability can be explained by localized damage caused by GP breakthrough of the filled SW. This study probably provides important guidance for the design, operation, and management of MSW landfills.

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Simulation of gas transport in a landfill with layered new and old municipal solid waste

Scientific Reports ◽

10.1038/s41598-021-88858-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Tao Zhang ◽

Jianyong Shi ◽

Xun Wu ◽

Hai Lin ◽

Xiulei Li

Keyword(s):

Municipal Solid Waste ◽

Pressure Distribution ◽

Solid Waste ◽

Gas Transport ◽

Transport Model ◽

Gas Permeability ◽

Gas Production ◽

Gas Pressure ◽

Anisotropy Ratio ◽

The Difference

AbstractAverage biodegradation rate of newly filled municipal solid waste (MSW) in landfills is relatively fast, and the landfill gas produced by the new MSW biodegradation can cause great variations in gas pressure. To predict the gas pressure distribution in the MSW layer, a one-dimensional gas transport model is established in this study. The following factors are considered in this model: (1) the variation of gas permeability with depth; (2) the anisotropy ratio of gas permeability; (3) the settlement caused by waste biodegradation. Furthermore, a single peak model for gas production is applied as the source term of gas production. The equation for settlement caused by waste biodegradation is presented, and the time of peak gas production rate is obtained by fitting the settlement of the newly filled layer. The stratification of the unsaturated and saturated regions is taken into account by distinguishing the difference in gas saturation. The layering of the new and old waste layers is considered by distinguishing the difference in the length of time that waste has been degraded to produce gas. Based on the method of numerical calculation, the gas pressure distribution in the landfill with layered new and old MSW is well simulated. The position where the maximum gas pressure occurs is found. The sensitivity analysis shows that the influence of the anisotropy ratio on gas pressure distribution is more significant.

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Simulation of Gas Transport in A Landfill With Layered New and Old Municipal Solid Waste

10.21203/rs.3.rs-151628/v1 ◽

2021 ◽

Author(s):

Tao Zhang ◽

Jianyong Shi ◽

Xun Wu ◽

Hai Lin ◽

Xiulei Li

Keyword(s):

Municipal Solid Waste ◽

Pressure Distribution ◽

Solid Waste ◽

Gas Transport ◽

Transport Model ◽

Gas Permeability ◽

Gas Production ◽

Gas Pressure ◽

Anisotropy Ratio ◽

The Difference

Abstract Average biodegradation rate of newly filled municipal solid waste (MSW) in landfills is relatively fast, and the landfill gas produced by the new MSW biodegradation can cause great variations in gas pressure. To predict the gas pressure distribution in the MSW layer, a one-dimensional gas transport model is established in this study. The following factors are considered in this model: (1) the variation of gas permeability with depth; (2) the anisotropy ratio of gas permeability; (3) the settlement caused by waste biodegradation. Furthermore, a single peak model for gas production is applied as the source term of gas production. The equation for settlement caused by waste biodegradation is presented, and the time of peak gas production rate is obtained by fitting the settlement of the newly filled layer. The stratification of the unsaturated and saturated regions is taken into account by distinguishing the difference in gas saturation. The layering of the new and old waste layers is considered by distinguishing the difference in the length of time that waste has been degraded to produce gas. Based on the method of numerical calculation, the gas pressure distribution in the landfill with layered new and old MSW is well simulated. The position where the maximum gas pressure occurs is found. The sensitivity analysis shows that the influence of the anisotropy ratio on gas pressure distribution is more significant.

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Combustible gas production during catalytic pyrolysis of municipal solid waste

Energy Sources Part A Recovery Utilization and Environmental Effects ◽

10.1080/15567036.2015.1076908 ◽

2017 ◽

Vol 39 (3) ◽

pp. 277-283 ◽

Cited By ~ 1

Author(s):

Di Yang ◽

Qiang Xie ◽

Xinqian Shu ◽

Yiman Jia ◽

Jinwei Jia ◽

...

Keyword(s):

Municipal Solid Waste ◽

Solid Waste ◽

Catalytic Pyrolysis ◽

Gas Production ◽

Combustible Gas

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Improving the Slope Stability of Municipal Solid Waste Dumps Using Reinforced Soil Berms: A Case Study

Proceedings of the 8th International Congress on Environmental Geotechnics Volume 2 - Environmental Science and Engineering ◽

10.1007/978-981-13-2224-2_3 ◽

2018 ◽

pp. 18-25

Author(s):

A. Agarwal ◽

M. Datta ◽

G. V. Ramana ◽

R. Satyakam

Keyword(s):

Slope Stability ◽

Municipal Solid Waste ◽

Solid Waste ◽

Reinforced Soil ◽

Waste Dumps

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A hybrid method for quasi-three-dimensional slope stability analysis in a municipal solid waste landfill

Waste Management ◽

10.1016/j.wasman.2011.07.012 ◽

2011 ◽

Vol 31 (12) ◽

pp. 2484-2496 ◽

Cited By ~ 8

Author(s):

L. Yu ◽

F. Batlle

Keyword(s):

Stability Analysis ◽

Slope Stability ◽

Municipal Solid Waste ◽

Solid Waste ◽

Hybrid Method ◽

Three Dimensional ◽

Slope Stability Analysis ◽

Municipal Solid Waste Landfill ◽

Waste Landfill

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Characteristics of ground motion and threshold values for colluvium slope displacement induced by heavy rainfall: a case study in northern Taiwan

Natural Hazards and Earth System Science ◽

10.5194/nhess-16-1309-2016 ◽

2016 ◽

Vol 16 (6) ◽

pp. 1309-1321 ◽

Cited By ~ 5

Author(s):

Ching-Jiang Jeng ◽

Dar-Zen Sue

Keyword(s):

Slope Stability ◽

Heavy Rainfall ◽

Slope Failure ◽

Drainage System ◽

Threshold Value ◽

Slope Instability ◽

Disaster Prevention ◽

Strain Gages ◽

Slope Displacement ◽

Northern Taiwan

Abstract. The Huafan University campus is located in the Ta-lun Shan area in northern Taiwan, which is characterized by a dip slope covered by colluvium soil of various depths. For slope disaster prevention, a monitoring system was constructed that consisted of inclinometers, tiltmeters, crack gages, groundwater level observation wells, settlement and displacement observation marks, rebar strain gages, concrete strain gages, and rain gages. The monitoring data derived from hundreds of settlement and displacement observation marks were analyzed and compared with the displacement recorded by inclinometers. The analysis results revealed that the maximum settlement and displacement were concentrated on the areas around the Hui-Tsui, Zhi-An, and Wu-Ming buildings and coincided with periods of heavy rainfall. The computer program STABL was applied for slope stability analysis and modeling of slope failure. For prevention of slope instability, a drainage system and tieback anchors with additional stability measures were proposed to discharge excess groundwater following rainfall. Finally, threshold value curves of rainfall based on slope displacement were proposed. The curves can be applied for predicting slope stability when typhoons are expected to bring heavy rainfall and should be significant in slope disaster prevention.

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Rheology of sludge from double phase anaerobic digestion of organic fraction of municipal solid waste

Water Science & Technology ◽

10.2166/wst.2000.0055 ◽

2000 ◽

Vol 41 (3) ◽

pp. 51-59 ◽

Cited By ~ 12

Author(s):

P. Battistoni ◽

P. Pavan ◽

J. Mata-Alvarez ◽

M. Prisciandaro ◽

F. Cecchi

Keyword(s):

Anaerobic Digestion ◽

Municipal Solid Waste ◽

Solid Waste ◽

Pilot Scale ◽

Gas Production ◽

Organic Loading Rate ◽

Second Phase ◽

Organic Fraction ◽

Double Phase ◽

Long Term Experiment

In this paper experimental results on the anaerobic digestion of sewage sludge and organic fraction of municipal solid waste (OFMSW) by using a double phase process are reported. The long-term experiment has been carried out on a pilot scale plant, performed in different sets of operative conditions, during which granulometric distributions of particles in sludges and rheological properties of sludges were monitored. A significant fluidification of sludge was evidenced in the meso-thermo process, especially taking into account the variation in sludge behaviour from the first to the second phase. In the thermo-thermo process a fluidification higher than that shown in meso-thermo conditions is not observed, this suggesting that better results in terms of sludge conditioning can be obtained in a long time spent in thermophilic anaerobic digestion. Total volatile solids (TVS) and total fixed solids (TFS) become the most important parameters when mathematical modelling is applied to these processes.In the acidogenic phase, hydraulic retention time (HRT) and temperature are used to determine rigidity coefficient (RC), while only temperature is needed for yield stress (YC). Organic loading rate (OLR) and specific gas production (SGP) exert an important role in methanogenic phase description.

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