System for the Conversion of Coal to a Gas of Specified Composition

Abstract

The present invention provides a coal gasification system with an integrated control subsystem. The system generally comprises, in various combinations, a gasification reactor vessel (or converter) having one or more processing zones and one or more plasma heat sources, a solid residue handling subsystem, a gas quality conditioning subsystem, as well as an integrated control subsystem for managing the overall energetics of the conversion of coal to energy and maintaining all aspects of the gasification processes at an optimal set point The gasification system may also optionally comprise a heat recovery subsystem and / or a product gas regulating subsystem.

Description

FIELD OF THE INVENTION[0001]This invention relates to the gasification of coal, and in particular to a process and apparatus for the conversion of coal to a gas having a specified composition.BACKGROUND OF THE INVENTION[0002]Coal of varying grades can be used as a primary feedstock for gasification. This includes low grade, high sulfur coal, which is not suitable for use in coal-fired power generators due to the production of emissions having high sulfur content. Waste coal particles and silt that remain after coal has been mined, sorted and washed is also useful for gasification. Coal can typically be gasified with oxygen and steam to produce so-called “synthesis gas” containing carbon monoxide, hydrogen, carbon dioxide, gaseous sulfur compounds and particulates. The gasification step is usually carried out at a temperature in the range of about 650° C. to 1200° C., either at atmospheric pressure or, more commonly, at a high pressure of from about 20 to about 100 atmospheres.[0003]...

AI Technical Summary

Benefits of technology

"The present invention provides a system for converting coal to a gas with a specific composition. The system includes a gasification reaction vessel with plasma heat sources and a coal input means for adjustable coal feed rate. The system also has a process additive input means for adjustable process additive feed rate and an outlet for the output gas. The system includes a solid residue handling subsystem and a gas quality conditioning subsystem. An integrated control system monitors system parameters and sends signals to regulators to effect change in the system. The gasification system may also have a heat recovery subsystem and a product gas regulating subsystem."

Problems solved by technology

This includes low grade, high sulfur coal, which is not suitable for use in coal-fired power generators due to the production of emissions having high sulfur content.

The gas produced during the gasification of coal is usually very hot and dirty, and requires further treatment to convert it into a useable product.

These machines are designed to function within a very strict range of characteristics and are often very sensitive to changes in gas characteristics.

In addition to affecting the efficiency of engine operation, a deviation in the gas characteristics may even have a negative effect on engine operation.

For example, changes in the gas characteristics can affect the corrosion protection properties of the lubricating oil in an engine, as well it can affect emissions, efficiency, knock and combustion stability.

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