About Waste to Energy Systems

Raven Knight has been working with numerous developers to provide its clients with reliable waste to energy technology that is proven and operational. Check back for more information soon.

Waste to Energy is the process of creating energy in the form of electricity, synthetic fuels or heat from the combustion, gasification or pyrolysis/thermal distillation of waste source.  WTE is a form of energy recovery. WTE processes produce electricity  or produce a combustible fuel commodity, such as methane, methanol, ethanol or synthetic fuels.

What is often ignored is the pre-treatment of the material and the tertiary conversion technology that takes the syngas or steam and produces fuel or electrical power. Raven Knight works with suppliers and developers of combustion technologies and also thermal distillation/pyrolysis and gasification technologies, as well as pre-treatment technologies providing sorting and preparation of the materials and Fischer Tropsch developers and turbine manufacturers to produce fuel and electricity.

Here is more information on the types of WTE technology available.  (From 2008, in the process of updating).

 

Combustion

Combustion reduces volume of waste and when properly equipped, can convert water into steam to fuel heating systems or generate electricity through using a turbine. Combustion uses oxygen and the material is directly heated.

Gasification

Gasification is a process that converts carbonaceous materials, such as biomass and organic materials as well as coal or petroleum into carbon monoxide and hydrogen by reacting the raw material at high temperatures with a controlled amount of oxygen and/or steam. The resulting gas mixture is called synthesis gas or syngas and is itself a fuel.

The advantage of gasification is that using the syngas is potentially more efficient than direct combustion of the original fuel because it can be combusted at higher temperatures or even in fuel cells, so that the thermodynamic upper limit to the efficiency defined by Carrot’s rule is higher or not applicable. Syngas may be burned directly in internal combustion engines or used in turbines to produce electricity, used to produce methanol and hydrogen, or converted via the Fischer-Tropsch process into synthetic fuel.  In addition, the high-temperature combustion refines out corrosive ash elements such as chloride and potassium, allowing clean gas production from otherwise problematic fuels.

Gasification relies on chemical processes at elevated temperatures >700°C, which distinguishes it from biological processes such as anaerobic digestion that produce biogas.

Pyrolysis

Pyrolysis/Thermal Distillation ‘Pyrolysis’ is the chemical decomposition of organic materials by heating in the absence of oxygen or any other reagents, except possibly steam. Also no direct contact is made with the material and the flame, as in gasification. It is used to convert complex materials such a biomass or waste into synthetic gas which can be used to fuel a turbine or made into a sythetic fuel such as sythetic diesel or jet fuel. One beneficial bi-product of pyrolysis is biochar, the ash remaining after the process which can be used as a very beneficial soil amendment in agricultural applications.

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