Development of a sugarcane leaf gasifier for electricity generation

Abstract

This study reports the development of a gasifier running on sugarcane leaves. A 15 kVA diesel generator set was operated for over 200 h using this gasifier. The gas flow rate and calorific value were 3–4 Nm 3 kWh −1 and 3.5-5.0 MJ Nm −3, respectively. The cold gas efficiency was 35–60% over the entire range of loads tested (3.5–11.3 kW). The diesel saving (DS) was nearly independent of the load and was 70–93% at a pressure drop ( ΔP) of 40 cm water gauge (WG); it reduced to 50–70% at ΔP > 50 cm WG. The indicated thermal efficiency reduced from 18–29% at 3.5–11.3 kW loads, respectively, in the diesel-alone mode, to 16–26% at the corresponding loads in the dual-fuel mode. About 15–28% by weight of the fuel was converted into char with a calorific value of ∼19 MJ kg −1. This char, when mixed with a suitable binder and briquetted, formed an excellent fuel for wood stoves. An economic analysis using the Levelised Annual Cost (LAC) method showed that such gasifiers are more suited for direct heat applications than for shaft power applications at the present level of technology.