Method and installation for conversion into fuel of organic material originating for instance from domestic waste

Abstract

A method is provided for converting organic material from domestic refuse into fuel for use in a pulverized coal power plant, comprising of mixing the organic material with at least one flammable material while adding binder, and pressing the mixture to form hard, relatively brittle agglomerates. Further provided is an installation for converting organic material from domestic refuse into fuel, comprising a device for mixing the organic material with at least one flammable material while adding binder, and device for pressing the mixture to form hard, relatively brittle agglomerates.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] Pursuant to 35 U.S.C. §119, this application claims priority to the filing date of Dutch Patent Application Serial No. 1027726 filed Dec. 13, 2004; the disclosure of which is herein incorporated by reference. INTRODUCTION [0002] The invention relates to a method for converting organic material into fuel. The invention relates particularly to a method with which the organic material can be converted into a type of fuel which can be ground to powder and is thereby suitable for burning in a pulverized coal power plant. In this application “organic material” is understood to include the combustible fraction of domestic refuse or equivalent industrial waste, so-called RDF (Refuse Derived Fuel). Fibrous material, such as for instance wood chippings, also falls however within this designation. [0003] It is already known per se to convert domestic refuse into a fuel which can be used in electricity power plants. Compared to the combustion of un...

AI Technical Summary

Benefits of technology

[0003] It is already known per se to convert domestic refuse into a fuel which can be used in electricity power plants. Compared to the combustion of unsorted waste in waste incineration plants (WIPs), this has the advantage that the combustion efficiency of an average power plant is considerably higher, while possibly reusable materials are moreover prevented from being burned together with the waste. A problem however is that costly additional measures and provisions are necessary for this purpose, while the thus formed fuel has a lower net heating value than coal, thereby reducing the output of the power plant.

[0008] By pressing the mixture such that hard and brittle agglomerates are created, these products of the pressing process can be admixed directly to coal and pulverized together therewith and fed to the furnace of a high-efficiency electricity power plant. Owing to the strong compressing thereof, with pressures which can be in the order of 30 MPa, the agglomerates have a long storage life and can, like coal, be stored outside.

[0015] An efficient, energy-saving pressing is achieved when the mixture is pressed in a pellet press with flat die.

[0020] In addition, the installation can further be provided with a device for reducing the waste in size placed between the recovering device and the mixing device.

[0025] These aspects are simple to realize structurally when the pressing device comprises at least one pellet press with flat die. Such pellet presses are commercially available from different suppliers, and enable high pressures and temperatures to be reached with relatively low energy consumption.

Problems solved by technology

A problem however is that costly additional measures and provisions are necessary for this purpose, while the thus formed fuel has a lower net heating value than coal, thereby reducing the output of the power plant.

The heretofore known methods, including that of the above stated patent application, have the drawback that not only the non-combustible fractions, but also per se combustible materials such as wood or plastics, have to be separated from the waste before it can be mixed with flammable material and pressed to form granules.

If granules obtained with the methods now known were to be ground, just as coal, in ball mills, but then without prior separation of plastics and wood, the plastics and wood would as it were be smeared, and the filters of the ball mills would become blocked.

The separation of materials such as wood and plastics does however require one or more additional steps, whereby the known methods are relatively time-consuming, complex and expensive.

Images