Search results for "landfill ga"
showing 10 items of 17 documents
Assessing Methane Emission and Economic Viability of Energy Exploitation in a Typical Sicilian Municipal Solid Waste Landfill
2018
Sanitary landfills for municipal solid waste (MSW) represent one of the major anthropogenic source of GHGs emissions and are directly responsible of the climate changes we are facing nowadays. Indeed, the biodegradable organic matter of MSW undergoes anaerobic digestion producing the landfill gas (LFG), whose main components are CH4 and CO2. Therefore, biomethane energy exploitation in MSW landfills will reduce GHGs emission positively affecting the global warming. The aim of the present study was to assess the methane production in a Sicilian landfill by comparing the results from field measurements of methane emission and the estimates achieved by applying different mathematical models. A…
Landfill gas upgrading with pilot-scale water scrubber: Performance assessment with absorption water recycling
2012
Abstract A pilot-scale counter current absorption process for upgrading municipal solid waste (MSW) landfill gas to produce vehicle fuel was studied using absorption, desorption and drying units and water as an absorbent. Continuous water recycling was used without adding new water to the system. The process parameters were defined by a previous study made with this pilot system. The effect of pressure (20–25 bar), temperature (10–25 °C) and water flow speed (5.5–11 l/min) on the upgrading performance, trace compounds (siloxanes, halogenated compounds) and water quality were investigated. Raw landfill gas flow was kept constant at 7.41 Nm3/h. Methane (CH4) and carbon dioxide (CO2) contents …
Upgrading landfill gas using a high pressure water absorption process
2014
Abstract The upgrading of landfill gas (methane 54.2 ± 2.0%, carbon dioxide 42.1 ± 2.4% and nitrogen 3.7 ± 1.2%) was studied with a pilot-scale high pressure water absorption system consisting of absorption, desorption and gas drying units. The gas was upgraded in two phases and with two absorption columns operating in sequence in pressures up to 180 bar, and with initial pressures of 8 and 10 bar. This type of high pressure process, where water is used for increasing the gas pressure, does not need a separate compression unit to produce the gas pressure required by gas vehicles. Product gas with a methane contents ranging from 83.0% to 92.1% was achieved with differing process parameters, …
Emissions of Greenhouse Gases and Climate Politics in the Latvian Waste Sector
2015
According IPCC guidelines for determination of greenhouse gases in waste management (IPCC 2006) the quantity of greenhouse gases must be determined for the emissions of CO2, CH4, N2O for such treatment activities: disposal of solid waste, biological treatment of solid waste and incineration and open burning of waste. Presented report reviles the current situation of this field in Latvia and conclusions on its minimization actions. The data received from Latvian environmental data bases shows that the quantity of disposed unsorted municipal waste is rising and created sanitary landfill system with anaerobic digestion of bio mas (the content of it in the disposed waste reaches 40–50 %) is pro…
Methane oxidation in a boreal climate in an experimental landfill cover composed from mechanically–biologically treated waste
2007
The present study evaluated microbial methane (CH4) oxidation in a boreally located outdoor landfill lysimeter (volume 112 m3, height 3.9 m) filled with mechanically-biologically treated waste (MBT residual) and containing a cover layer made from the same MBT residual. The calculations based on gas emission and pore gas measurements showed that, between April and October 2005, a significant proportion (96%) of the methane produced (23 l CH4 m(-2) d(-1)) in the lysimeter was oxidized. Methane was oxidized mainly at the depths of 35-75 cm, as indicated by the upward decrease both in the methane concentration and in the methane-to-carbon dioxide ratio in the pore gas. Lower methane oxidation (…
Evaluation of the current status of operating and closed landfills in Russia, Finland and Ireland with regard to water pollution and methane emission
2003
The annual production of municipal solid wastes (MSW) in Russia, Finland and Ireland in the late 1990s accounts for 37.5, 2.5 and 2.05 mln. tonnes or 252, 488 and 566 kg per capita, respectively. 96.5, 64 and 91% of these wastes (for Russia, Finland and Ireland, correspondingly) are currently disposed of via landfilling. However, nowadays, MSW management in these countries is undergoing drastic changes (source separation, closure of old landfills, reduction of the number of landfills etc.) forced by recent legislation set by the European Union and Russian authorities. This paper evaluates the current status of MSW landfills, as well as information on current leachate and methane emissions i…
Landfill gas upgrading with countercurrent water wash.
2006
A pilot-scale countercurrent absorption process for upgrading landfill gas to produce vehicle fuel was studied using absorption and desorption units and water as absorbent. The height-to-diameter ratio of the absorption column used was 3:1 instead of the more conventionally used 20:1 ratio, and a higher pressure was used along with a lower water flow rate. The effects of pressure (10-30 bar) and water and gas flow-ratios on the upgrading process were studied. Methane content in the product gas increased to near or above 90% with both gas flows (50 and 100 l/min) used at over 20 bar pressure with 10 l/min water flow and at 30 bar pressure with 5l/min water flow. Carbon dioxide content with t…
Uncontrolled methane emissions from a MSW landfill surface: Influence of landfill features and side slopes
2013
Sanitary landfills for Municipal Solid Waste (MSW) disposal have been identified as one of the most important anthropogenic sources of methane (CH4) emissions; in order to minimize its negative effects on the environment, landfill gas (LFG) recovery is a suitable tool to control CH4 emissions from a landfill site; further, the measurement of CH4 emissions can represent a good way to evaluate the effectiveness of LFG recovering systems. In general, LFG will escape through any faults in the landfill capping or in the LFG collection system. Indeed, some areas of the capping can be more permeable than others (e.g. portions of a side slope), especially when considering a temporarily capped zone …
Evaluation of methane emissions from Palermo municipal landfill: Comparison between field measurements and models
2010
Methane (CH(4)) diffuse emissions from Municipal Solid Waste (MSW) landfills represent one of the most important anthropogenic sources of greenhouse gas. CH(4) is produced by anaerobic biodegradation of organic matter in landfilled MSW and constitutes a major component of landfill gas (LFG). Gas recovery is a suitable method to effectively control CH(4) emissions from landfill sites and the quantification of CH(4) emissions represents a good tool to evaluate the effectiveness of a gas recovery system in reducing LFG emissions. In particular, LFG emissions can indirectly be evaluated from mass balance equations between LFG production, recovery and oxidation in the landfill, as well as by a d…
Group-specific quantification of methanotrophs in landfill gas-purged laboratory biofilters by tyramide signal amplification-fluorescence in situ hyb…
2008
The aim of this study was to quantitatively analyse methanotrophs in two laboratory landfill biofilters at different biofilter depths and at temperatures which mimicked the boreal climatic conditions. Both biofilters were dominated by type I methanotrophs. The biofilter depth profiles showed that type I methanotrophs occurred in the upper layer, where relatively high O(2) and low CH(4) concentrations were present, whereas type II methanotrophs were mostly distributed in the zone with high CH(4) and low O(2) concentrations. The number of type I methanotrophic cells declined when the temperature was raised from 15 degrees C to 23 degrees C, but increased when lowered to 5 degrees C. A slight …