THERMAL SCIENCE

International Scientific Journal

EXPERIMENTAL STUDY ON HEAT TRANSFER AND FLUID-FLOW ENHANCEMENT OF A SPHERICAL SHAPE OBSTACLE SOLAR AIR PASSAGE

ABSTRACT
The combustion characteristics of blends of lignite with various organic waste materials are evaluated in this study in order to assess their potential for energy recovery. Different types of municipal solid waste (MSW) (i.e. paper, plastic, textile, organic), as well as sewage sludge and agri-residues (sunflower shells) samples were collected from the Western Macedonia region, northern Greece. Mixtures of each one of them with lignite in different proportions (30-50-70 wt%) were prepared. Proximate analysis, calorific value determination and thermogravimetry (TGA/DTG) were performed. Thermal parameters such as ignition temperature, total weight loss, maximum rate of weight loss, peak and burnout temperatures and burnout time were determined from the TG/DTG profiles of the raw materials and their blends. The combined utilization of proximate analysis, calorific value determination and TG/DTG method proved to be an effective method for a preliminary assessment of the energetic potential of raw solid waste “combustible” materials and their blends with lignite. The analytical results revealed that most of the blends are promising for energy recovery. Regarding the raw wastes, sunflower shells were the most reactive. A non-synergistic effect was found for the blends. Organic and sewage sludge blends revealed the lowest combustibility, which is attributed to the high content of inorganic matter and the heterogeneity of these two types of wastes.
KEYWORDS
PAPER SUBMITTED: 2017-06-23
PAPER REVISED: 2017-10-04
PAPER ACCEPTED: 2017-10-10
PUBLISHED ONLINE: 2017-11-18
DOI REFERENCE: https://doi.org/10.2298/TSCI170623220S
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2019, VOLUME 23, ISSUE Issue 2, PAGES [751 - 761]
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© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence