Gasification – Waste Management at its Best

Renewable energy is undoubtedly a current issue; increasing awareness of the dangers of climate change, along with greater government involvement has made the prospect of renewable energy an incredibly exciting and attractive sector. What many people remain unaware of however is the scope of a sector named ‘renewable energy’ instead focusing on the obvious examples of clean power such as wind turbines or hydroelectricity; the beauty of renewable energy is in fact that it can potentially be sourced from such a wide variety of methods. This is all the more attractive when we consider the current reliance and dependence on fossil fuels, and compare it to the relative freedom and versatility of renewable energy from a diverse range of sources!

A specific example of this diversity is the idea of gasification technology, being a clean source of renewable energy; simply put, its versatility comes from the fact that the produced fuel can be generated from a wide variety of fuels, maximizing its longevity as a fuel source. As a theory, the gasification method has been employed for more than 180 years, providing fuel for a variety of sources including town gas (used for lighting and cooking during the 19th century), blast furnaces and the production of synthetic chemicals. However an increased focus on the value of renewable energy has seen its versatility realized in more recent years as a source of fuel.

How does it work then? Gasification is a process that converts organic or fossil based materials into a combination of carbon monoxide, hydrogen and carbon dioxide known as “syngas.” The chemical reaction involved in creating this syngas itself involves combustion that can be used for power, and the product gas can itself be combusted. The syngas could alternatively be converted efficiently into other fuel forms such as dimethyl ether, methane or a synthetic diesel substitute; regardless of its final form, the process of gasification is totally clean. Interestingly enough, while the combustion of the fuel does release carbon dioxide emissions, these can be effectively cancelled out by the process of creating the biomass that would be converted into fuel via gasification.

Gasification is thus a great example of the versatility of a renewable energy source, in that a wide variety of biomass can be used in theory. Sources include rape seed, wood pellets and chips, sewage and agricultural wastes/crop residues. Gasification technology thus provides a varied and valuable example of how renewable energy can be used to recycle and profit from previously wasted products, producing clean energy in the form of a variety of fuels. In principle, gasification technology can run on a variety of inputs to create an even wider variety of outputs, making its application as a potential replacement for finite fossil fuel even more valuable.

Article by George Hosegood.