Gasification is not combustion. Unlike combustion, plasma gasification does not create any unwanted emmissions or pollutants. Because of extreme temperatures, complex compounds are broken down into individual atoms, which then create synthesis gas that can be used as a fuel or raw material for forther use. A by-product of the process is inert slag, which can be used as a construction material. A plasma torch is a tool to make thermal plasma, which plasma gasification technology uses to provide the energy necessary to break down the input materials. Plasma is an ionised, conductive gas at a temperature of 4 – 5 000 °C, which arises when a stream of the carrier gas(air enriched with 93 % oxygen) is passed through an arc discharge. The extremely high temperature and energy density enable the rapid and comprehensive breakdown of all of the organic substances into their basic elements. The parallel process of partial oxidation provides the resulting gasification product – synthesis gas (CO + H2). Plasma torches were originally developed to test the resistance of the space shuttle’s ceramic tiles, which encounter temperatures of over 2500 °C upon re-entry into the atmosphere. All combustion processes produce ash as a by-product. For the majority of projects this is a serious environmental, and thus financial, problem. High temperature, plasma gasification technology is very different in this aspect as, thanks to the high temperatures, its only by-product is not ash but slag, which is five times less leachable than glass and can be used as a building material.

After crubbing and cooling the gas, we obtain gaseous fuel with between ten to twelve mega joules of energy per kilogram. At this volume of energy we can either process the gas in cogeneration engines, for lesser amounts of gas (6000 M3/hour – smallest installation), or in gas turbines working in a combine cycle with turbine steam. Likewise, for smaller installations working with cogeneration units the energy from the cooled gas and the engines’exhaust combustion products is used for making electricity in a steam turbine.

Another possible use of gasification technology, with the subsequent electricity and heat energy production, is processing sewage sludge in the Form of dewatered sludge after anaerobic fermentation or dewatered mixed raw sludge. By using the proposed technology there is a Fundamental change from the standpoint of the valid legislation. The modification means that due to drying and sanitising, the input material stops being waste and becomes biomass. The energy value of fuel from dried sewage sludge is around 12,9 MJ/kg. Apart from resolving the problem of disposing of waste by landfilling dewatered sludge after anaerobic fermentation, it is also possible to count on the benefits from selling the electricity.