A study of the self-heating efficiency of waste mussel shell from Laem Fa Pha subdistrict municipality area, Phra Samut Chedi, Samut Prakan by comparing with waste cockle, oyster, and horse mussel shells

Abstract

In Laem Fa Pha Subdistrict Municipality Area, Phra Samut Chedi, Samut Prakan, Thailand; due to the high domestic consumption and exports of shell products, large amounts of mussel, cockle, oyster, and horse mussel shells wastes are produced at the different stages of production. The high content of CaCO3 in shell waste can be converted as a raw material for value-added products such as self-heating powders, CaO. This research has the objective of transformation of CaCO3 in wasted shells of four bivalve species—i.e., mussel, cockle, oyster, and horse mussel—to CaO by calcination at 800, 900, 950 and 1,000 °C. While three species: mussel, cockle and oyster shells were completely converted at 900 °C, horse mussel shell was highly calcined at 1,000 °C. The calcined powder obtained from each species was investigated for its self-heating efficiency by measuring heat of the solution in water. The enthalpy of solution for horse mussel, oyster, cockle, and mussel calcined powder was found to be −690, −681, −604, and −598 cal/mol, respectively. This result denotes the horse mussel shells having the highest self-heating efficiency relative to oyster, cockle, and mussel shells. Even though mussel shells have a lower relative efficiency, they are still a viable economical option in the production of a self-heating product due to their excessive availability in the area.