Effects of Secondary Chamber on Gas Yield by Pre-Vacuum Chamber Pyrolysis of Rubber Wood

Hiroki Homma,Hiroomi Homma,Sihar Siahaan

doi:10.4236/jsbs.2017.71001

Abstract

Global warming awareness criticizes further usage of fossil fuels and insists promotion of renewable energy usage. Additionally, many people in rural areas of developing countries cannot access electricity. To solve this sort of energy crisis including global warming, current authors developed a proto-type of a pyrolysis plant equipped with a prevacuum chamber, which can be used to produce combustible gases for an engine generator in rural areas where people cannot access electricity. The plant is simple and easily maintained in consideration of special conditions that a rural area can receive very few maintenance service, technical assistance, and supply of spare parts. However, gas yield obtained by the proto-type of plant was around 20 wt% of feedstock. One way to enhance gas yield from this proto-type of plant is to utilize reaction of secondary tar cracking. This research work aims to examine possibility of gas yield enhancement keeping a simple structure of the proto-type of plant and using a simple technique of secondary tar cracking. Two tar cracking methods are examined: one is homogeneous tar cracking and the other is heterogeneous tar cracking using catalysis. In the homogeneous tar cracking, pyrolysis gases must be heated up to 650oC to 700oC and in the heterogeneous tar cracking, wood char is used as catalysis, because wood char is byproduct of pyrolysis. It is concluded that the homogeneous tar cracking is quite unlikely in the secondary chamber, but on the other hand, heterogeneous tar cracking using wood char can produce 30 wt% of gas yield from 1 kg of feedstock.

Highlights

United Nations Framework on Climate Change, 21st Conference of Parties (COP21), declared the statement that the global common and long term target is to suppress average temperature raise under 2 degree, even 1.5 degree from the average temperature before industrial revolution era [1]
To increase combustible gas yield, a secondary tar cracking reaction is introduced to the proto-type plant equipped with a pre-vacuum chamber for rubber wood pyrolysis, which has been developed for self-supply of electricity to rural people [4]
In order to enhance efficiency of a simple and less maintained proto-type plant of biomass pyrolysis that can be used for a family living in rural areas where they cannot access electricity, concept of secondary tar cracking is introduced into the proto-type plant

Summary

Introduction

United Nations Framework on Climate Change, 21st Conference of Parties (COP21), declared the statement that the global common and long term target is to suppress average temperature raise under 2 degree, even 1.5 degree from the average temperature before industrial revolution era [1]. All the participant countries must definitely declare their concrete targets. They must make serious efforts to reduce carbon dioxide emission resulting global warming. Supply of electricity does not match with the demand. They still use fossil fuel like coal for power generation plants, for instance China and Indonesia. The study by IAE indicated that more than one billion people in the world cannot access electricity [3]. Such people live in rural areas and are not usually covered by grids of power supply

Objectives

Methods

Findings

Conclusion