CHOREN Coal Gasification® Process
The CCG® technology is based on a longtime tested process of coal gasification for the production of a high-purity, energy-rich synthesis gas.
This is the feedstock for the production of classic synthesis gas products such as methanol and ammonia, is used for the production of fuels or a variety of chemical raw materials or can be used to generate electricity and heat.
The application of the innovative burner concept for dry dust coal gasification and the subsequent waterquench results in the following advantages for the process:
- High quality of the synthesis gas: no aromatics, tars, phenols and condensates
- High feedstock variability: hard coal, lignite, petroleum coke, additions of waste materials and/or biomass
- Use of low-grade coal qualities with high ash contents possible
- Low investment costs due to compact designs and optimized waterquenching
- Low operating and high flexibility due to fast start-up and shut-down
- High plant availability due to simple and robust design
Use of synthesis gas
The high-energy and high-purity synthesis gas from biomass, coal or other carbonaceous feedstock can be used for the production of classic synthesis gas products, for power generation and for the production of fuels.
The CCG® process comprises three process stages
For the production of classical synthesis gas products, a synthesis gas is first obtained from biomass, coal or other carbon-containing feedstock using a gasification process.
1st stage
The fuel dust is pneumatically fed into a pressurized dosing and feeding system, in which it is fluidized and conveyed to the gasification reactor as a fuel dust carrier gas dispersion.
Advantages of this pneumatic dense phase feeding are high constancy and good controllability of the dust flow and an almost wear-free conveying even with abrasive dusts. Compared to a feed-in as a fuel dust-water suspension, a higher gasification efficiency is achieved with lower oxygen consumption, since no water from the suspension has to be evaporated additionally.
2nd stage
The gasification of the fuel dust is realized by partial oxidation of the coal within the entrained-flow together with oxygen and water steam at increased pressure. The carbon reacts with the oxygen to form carbon monoxide.
The CCG®-gasifier has a dust burner system optimized for maximum burnout. At the same time, the investment and operating costs are significantly reduced compared to those of known solutions.
The temperatures prevailing in the oxidizing flame range (> 2000 °C) above the melting point of the fuel ash guarantee a fast and almost complete fuel conversion. All hydrocarbons are completely converted.
A cooling screen covers the gasification chamber. The slag solidifies on the inside of the cooling screen and forms a protective layer against thermal attack to the reactor. As a thermotechnical favorable solution, the raw gas leaves the reaction chamber together with the molten slag, which significantly minimizes the risk of disturbance in slag outlet.
3rd stage
The separation of the raw gas from the liquid slag takes place during the subsequent quenching. The granulated slag can be used as a building material. After mechanical cleaning (Venturi, washing column), the raw gas is directed to the battery limit for further use.
Process Parameters
High-temperature gasification in the entrained-flow under pressure produces a very pure and energy-rich synthesis gas with advantageous properties.
Feedstock for the CCG® Process
Solid or liquid fuels containing ash, gases as auxiliary fuel
Requirements for the feedstock
- Minimum of ash content
- suitable ash composition (melting behavior, viscosity)
Additionally for solid fuels
- grindability
- drying up to the removal of the surface moisture (hard coal < 2%, lignite < 8..12%)
Coal
Almost all types of coal can be used, from lignite to anthracite coal. The use of ash-rich coals is also possible. The process is also suitable for salt coal, which has hardly been used materially so far.
Petcoke
This can be used in a mixture with coal or solely after adding a minimum quantity of ash without any problems.
Torrefied Biomass
Thermal treatment of the biomass under exclusion of air at 250 to 300 °C (pyrolytic decomposition) significantly improves its fuel properties. The torrefied biomass has a porous, coal-like structure, can be ground like coal, and added to the main fuel.
Other feedstock can be:
Heavy fuel oil, bitumen, organic solvents, natural gas, organic waste
CHOREN Industrietechnik GmbH
Glacisstraße 2
01099 Dresden
Germany
Phone: +49 351 285601-99
Telefax: +49 351 285601-50
E-Mail: info@choren.com
