Gasification vs incineration
Increasingly, gasification is being used to convert municipal solid waste, or MSW, into valuable forms of energy. While this type of waste has been burned, or incinerated, for decades to create heat and electricity, the gasification process represents significant advances over incineration. Speak to CTEC about the implications for your business.
Gasification converts MSW to a usable synthetic gas, or syngas.
In order to understand the advantages of gasification when compared to incineration, it’s important to understand the significant differences between the two processes: Incineration literally means to render to ash. Incineration uses MSW as a fuel, burning it with high volumes of air to form carbon dioxide and heat. In a waste-to-energy plant that uses incineration, these hot gases are used to make steam, which is then used to generate electricity. It is the production of this syngas which makes gasification so different from incineration.
In the gasification process the MSW is not a fuel, it's a feedstock for a high temperature chemical conversion process. In the gasifier the MSW reacts with little or no oxygen, breaking down the feedstock into simple molecules and converting them into syngas. Instead of making just heat and electricity as is done in a waste-to-energy plant using incineration, the syngas produced by gasification can be turned into higher valuable commercial products such as transportation fuels, chemicals, and fertilizers.
In addition, one of the concerns with incineration of MSW is the formation and reformation of toxic dioxins and furans, especially from PVC-containing plastics and other materials that form dioxins and furans when they burn. These toxins end up in exhaust streams by three pathways:
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By decomposition, as smaller parts of larger molecules
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By "re-forming" when smaller molecules combine; and/or
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By simply passing through the incinerator without change
CTEC technology is NOT incineration (where chemical bonds are broken by oxidation) and does not use heated exhaust gases to drive turbines with traditional toxic emissions and other associated issues of poor conversion plus high carbon footprint
CTEC’s proprietary system optimises gasification (chemical bonds are broken by thermal energy) to maximise conversion of solid waste feedstocks to Syngas. The production of syngas is maximised by CTEC’s proprietary monitoring and control system. Syngas is combusted under slightly over-stoichiometric conditions and the resultant hot gas stream produced by CTEC’s patented process powers a turbine to generate electrical and thermal energy with minimal emissions more efficiently than incineration.
Syngas is formed through a two-stage gasification process in oxygen-starved conditions – this process contrasts with typical waste incineration (850°C hot grate) which generates high chloride levels. The primary stage is endothermic - this harnesses the Boudouard reaction to produce syngas. In an oxygen starved chamber, there is no flame combustion, in stark contrast to incineration
CTEC Technology Differentiation
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CTEC technology is NOT incineration (where chemical bonds are broken by oxidation) and does not use heated exhaust gases to drive turbines with traditional toxic emissions and other associated issues of poor conversion plus high carbon footprint
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CTEC’s proprietary system optimises gasification (chemical bonds are broken by thermal energy) to maximise conversion of solid waste feedstocks to Syngas. The production of syngas is maximised by CTEC’s proprietary monitoring and control system. Syngas is combusted under slightly over-stoichiometric conditions and the resultant hot gas stream produced by CTEC’s patented process powers a turbine to generate electrical and thermal energy with minimal emissions more efficiently than incineration.
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Syngas is formed through a two-stage gasification process in oxygen-starved conditions – this process contrasts with typical waste incineration (850°C hot grate) which generates high chloride levels. The primary stage is endothermic - this harnesses the Boudouard reaction to produce syngas. In an oxygen starved chamber, there is no flame combustion, in stark contrast to incineration.
USA and UK governments have now realised that gasification in small scale overcomes many issues that are involved with incineration.
This differentiation is critical to The Environmental Protection Agency (federal government agency whose mission is to protect human and environmental health) in order to meet US Federal Clean Air Act requirements that distinguishes CTEC’s Gasification technology from Incineration regulatory programs and related National Emission Standards for Hazardous Air Pollutants as it expressly states “syngas gasification process is not incineration”.
CTEC Unit 1 Process Layout
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CTEC can deliver three different plant profiles with high operating IRRs
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CTEC Unit 1 gasification plant (shown) is designed to operate automatically and process waste continuously,
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Normal loading rate = 500kg of waste per hour
> generates 350 kW of electrical and 2.7 MWt of thermal energy.
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Each pallet of waste is loaded automatically into a Shredder before being conveyed into the CTEC system. No other pre-treatment is required.
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The mechanical unloading of the waste from the bin and skip into the system;
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The Shredding and conveyance of the waste into the Gasifier;
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The thermal treatment of the waste;
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The energy recovery from the waste/gas circuit to the water/steam circuit;
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The generation of electricity and thermal power;
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The treatment of the flue gas, and
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The collection of the sub-products and waste produced in the process.
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Electronic Control Unit
CTEC Process Overview
Core CTEC technology protected by range of patents representing effective barrier to entry and enabling international licencing model. Our system is a head to tail unique technology with many patents within the gasifier and the surrounding components, the items circled in red represent the heart of the technology, the Heat Exchanger and the control system, these two items pull the system together to deliver efficiency with Net Zero Emissions capability.
More efficient than incineration
Get an insight into how gasification could help you heat your premises. Contact CTEC.