Characterization of distillery sludge for its thermal properties and ascertaining its utilization as a low-cost fuel

Sustainable management of distillery sludge is one of the major problems faced by distillery industries worldwide and specifically in developing countries like India. Improper disposal of sludge leads to severe environmental hazards, such as soil pollution, groundwater contamination, obnoxious odours in the surrounding atmosphere and wind-blown litter. The present study is envisaged to use the distillery sludge as a low-cost fuel and to ascertain its applicability in other allied industries. The physico-chemical characterization of the collected sludge samples was carried out. The sludge samples were taken in different combinations of 25%, 40%, 50% and 75% (wt.%/wt.%) with coal samples and various parameters including physico-chemical and combustion properties were analysed. The calorific value of substrate (coal and sludge samples) was recorded as 5017 kcal/kg and 2237.2 kcal/kg, respectively. The 40% sludge combination with coal sample showed an optimum calorific value of 4659 kcal/kg which can be considered as the best combination among other tested combinations. Therefore, the present work utilizes the distillery by-product 'sludge' as a value-added product for the perspective of revenue generation and suggests an approach for cutting down the adverse effect of sludge from the distillery industry on the environment. (C) 2020 Elsevier Ltd. All rights reserved.