TY - JOUR
TI - Experimental study on heat transfer and fluid-flow enhancement of a spherical shape obstacle solar air passage
AU - Singh Yaswant
AU - Kumar Anil
AU - Maithani Rajesh
AU - Kumar Raj
JN - Thermal Science
PY - 2019
VL - 23
IS - 2
SP - 751
EP - 761
PT - Article
AB - 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.