Effect of storage on properties of pine needle cattle dung briquettes

Abstract

The study has been under taken to utilize abundantly available pine needles in hilly region of Uttarakhand state to mitigate the drudgery involved in collection of fuel wood from nearby forest for cooking. Pine needle briquettes have been prepared using cattle dung as binding agent in a proportion of 60:40 by weight with the help of a hydraulic press. Three levels of briquetting parameters, namely particle size (0.54, 1.5, 3.0mm), die pressure (2.8, 4.14 and 5.5MPa) and dwell time (15, 30, 45sec) have been taken. Heating value, ash content, moisture content, bulk density, crushing strength and water resistance capacity of briquettes have been evaluated. Bulk density and calorific values have decreased with increase in storage period for all types of briquettes. An overall reduction of 6.5% in bulk density and about 1.5% in calorific value has found during storage for a period of 60 days. However, all the briquettes have remained stable. Based on process optimization using RSM, briquettes prepared at highest die pressure of 5.5 MPa with 2.6 mm particle size and 15 seconds dwell time have proved to be optimal considering all the quality parameters of briquettes included in the study over the storage period of 60 days.