Peter Hall from Scion discusses different combustion technologies that can turn biomass into useable forms of energy, like heat or liquid fuel.
There are different ways of converting biomass into energy, depending on the resource and what the energy is used for. For example, combustion is the burning of a fuel source such as wood – a process that is being used by many New Zealand households as well as by industry that requires direct heat. A more complex process is when resources like wood are converted into either gas or a liquid fuel. Peter Hall also describes the process of pyrolysis, which describes the extraction of a liquid from biomass producing bio oil, a liquid fuel.
Conversion of biomass to energy is basically taking a raw material – and it can be a pile of wood chip or a bale of straw – which has energy embodied in it, and it’s a matter of how you get it out and for what purpose. So a real simple example is combustion, and most people have a fireplace at home, so you put wood in and you get heat out. There is actually an enormous demand for industrial heat in New Zealand – places like dairy factories, meat processing plants, cement works, steelworks and even creating electricity – all use fuel, which generates heat and steam, often.
And beyond that, there is more sophisticated technologies for taking biomass such as wood and converting it into gas, or ultimately into liquid fuels. And some of those would be gasification where you can convert wood into gas, and instead of the gas being burnt, it’s captured, and you can then compress it and clean it and you can either use it as a gas or you can then further refine it into a liquid fuel. Then there is pyrolysis, which is similar to gasification but you extract a liquid as opposed to a gas, and you end up with a product called bio oil, which has a number of constituent parts, but that can be further refined. Either the bio oil can be used as a fuel or you can further refine the bio oil into other products, although that is still very much a developmental technology, but there’s certainly potential there.
New Zealand Steel Ltd, Glenbrook, New Zealand
Page & Macrae Engineering Ltd
Trinec Iron and Steel Works