Well testing procedures, such as the Tier 3 methodology specified in the U.S. Code of Federal Regulations (CFR) Subtitle D, are commonly used for directly estimating landfill gas (LFG) emissions at municipal solid waste (MSW) landfills. Similar procedures are also used to estimate LFG generation rates for the design of LFG-to-energy projects. These methodologies assume that the LFG generation rate equals the extraction rate of a test gas well within its radius of influence (ROI). The ROI is defined as the distance from the extraction well at which the induced pressure drop is immeasurable by some standard of precision. Based on fluid dynamic principles, Tier 3 and similar methodologies are demonstrated to be incapable of providing reliable estimates of the LFG generation rate. These tests may either over- or underestimate the LFG generation rate depending on the precision with which the ROI is determined, but they will only coincidentally produce an estimate that accurately represents the actual LFG generation rate. Fluid dynamic principles dictate that the actual LFG generation rate can only be estimated if the pneumatic properties of the refuse and cover materials as well as the excess pressure in the refuse caused by LFG generation are known or can be estimated.
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http://dx.doi.org/10.1080/10473289.2003.10466180 | DOI Listing |
J Res Med Sci
October 2024
Institute of Hospital and Health Care Administration, National Yang Ming Chiao Tung University, Taipei, Taiwan.
Colloids Surf B Biointerfaces
January 2025
Department of Chemistry and Pharmacy, Physical Chemistry I, Friedrich-Alexander, Universität Erlangen-Nürnberg, Egerlandstr.3, Erlangen D-91058, Germany. Electronic address:
Shell-by-Shell (SbS)-functionalized NPs can be tailor-made by combining a metal oxide NP core of choice with any desired phosphonic acids and amphiphiles as 1st or 2nd ligand shell building blocks. The complementary composition of such highly hierarchical structures makes them interesting candidates for various biomedical applications, as certain active ingredients can be incorporated into the structure. Here, we used TiO and CoFeO NPs as drug delivery tools and coated them with a hexadecylphosphonic acid and with hexadecyl ammonium phenolates (caffeate, p-coumarate, ferulate), that possess anticancer as well as antioxidant properties.
View Article and Find Full Text PDFWaste Manag
December 2024
Anhui Province Tongyuan Environmental Environment Co., Ltd., China.
Landfills in developing countries are typically characterized by high waste water content and elevated leachate levels. Despite the ongoing biodegradation of waste in the highly saturated regions of these landfills, which leads to gas accumulation and bubble formation, the associated gas pressure that poses a risk to landfill stability is often overlooked. This paper introduces a landfill gas (LFG) bubble generation model and a two-fluid model that considers bubble buoyancy and porous medium resistance.
View Article and Find Full Text PDFWaste Manag
December 2024
MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou 310058, China; Center for Hypergravity Experimental and Interdisciplinary Research, Zhejiang University, Hangzhou 310058, China.
This study proposes a comprehensive evaluation method based on a two-stage model to assess greenhouse gas (GHG) emissions and reductions in high-food-waste-content (HFWC) municipal solid waste (MSW) landfills. The proposed method considers typical processes such as fugitive landfill gas (LFG), LFG collection, flaring, power generation, and leachate treatment. A case study of an HFWC MSW landfill in eastern China is considered to illustrate the evaluation.
View Article and Find Full Text PDFPediatr Surg Int
June 2024
Department of General Surgery, Ulumuqi Children's Hospital, Ulumuqi, China.
Background: Systemic Immune-Inflammation Index (SII), known as an easy, economical and useful marker, correlates with the balance of inflammation and immune response. However, the usefulness of SII in biliary atresia (BA) remains unclear. Therefore, we evaluated the relationship of SII level and postoperative clinical outcomes of BA.
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