PL177815B1 - Method of purifying crude coke oven tar - Google Patents

Abstract

The method of refining raw high-temperature tar from water and solids directly after it is produced, whereby, to the tar collected in the separator directly after the receiver of a bank of coke-ovens and in the decanter of the receiving water, a water-and-tar condensate is supplied from the gas fore-coolers and/or water received from the process of benzene separation, and the whole mix is heated to the temperature in which water-and-tar mixture is produced in the receiver of the bank of coke-ovens, and further it is separated in three-phase setting centrifuge, and vapours and out-gases from the whirling process are channelled to the raw gas pipeline.

Description

The present invention relates to a method of purifying coke oven tar from water and solids immediately after its production.

The coke industry uses many solutions for the separation and purification of tar in tar-water condensate separation plants. These solutions are based on sedimentation processes at atmospheric or elevated pressure and require a large number of tanks with a large volume. The disadvantage of these methods is the need to allocate a large area of the coking plant for tanks and settling tanks, and moreover, a great inconvenience is the need to remove high viscosity sediments from settling tanks and storage tanks. These operations are labor-intensive, energy-intensive and cause the emission of harmful substances to the environment.

The method according to the invention consists in that the tar collected in the separator, directly behind the coke oven receiver and in the receiver water separator, is supplied with tar-water condensate from gas pre-coolers and / or water obtained from benzol separation and heated to the temperature at which it is generated the water-tar mixture in the coke oven battery receiver and is separated on a three-phase sedimentation centrifuge, and the vapors and gases from the centrifugation process are discharged to the crude gas pipeline, the amount of water-tar condensate and / or water from the separation of benzene added to the tar before centrifugation is up to 100% by weight in relation to the amount of water contained in the tar before centrifugation.

The purification of raw coking tar is carried out in a technological installation, an example of which is shown in the figure.

The collecting water contaminated with tar flows by gravity from the separator 1 to the separator 2. In the separator 2, the raw tar is initially separated from the collecting water. Crude water tar contains 8 -s-15% by weight of water and a solids of 0.2-0.3% by weight. The receiver water is sent by pump 7 to spray the receiver, where the tar, coke and coal dust are essentially captured. The water-loaded raw tar flows by gravity to the manipulation tank 3.

From the reservoir 3, the raw tar is sent by a pump 8 through the heater 4 to a three-phase sedimentation centrifuge 5. Before it is fed to the centrifuge 5, the raw tar water-tar condensate from the preliminary coolers and / or separator water from benzol separation in the amount of up to 100% by weight are added to the crude tar. in relation to the amount of water contained in the raw tar discharged from the clarifier 2. In the heater 4, the raw tar is heated up to the temperature of water-tar mixture formation in the battery receiver. This is the temperature of the carbon dioxide gas exiting the receiver and saturated with water vapor. The raw tar prepared in this way is fed to the drum of a three-phase 5 sedimentation centrifuge, where the mixture is separated into three phases of different density:

- water

- purified raw tar

- solid parts

Crude tar cleaned after treatment contains:

- water in an amount less than 3% by weight

- solids and ash in an amount less than 0.08% by weight.

The purified tar is directed to the storage tank 6 and constitutes a high-quality commercial product for further processing.

The water separated from the tar is returned to the receiver water settler 2. Solids and sediments are dosed into the coal feed.

Vapors and gases from the centrifugation process are fed into the raw gas pipeline. The method according to the invention allows for resignation from clarifiers and tar separators previously used in coking plants and for avoiding cleaning of these tanks. The advantage of the method according to the invention is the high quality of the tar obtained and the recycling of all remaining gaseous, liquid and solid substances.

177 815

Publishing Department of the UP RP. Circulation of 70 copies. Price PLN 2.00.

Claims (2)

Patent claims 1. The method of purifying raw coke oven tar from water and solids immediately after obtaining it, characterized in that the tar collected in the separator directly behind the coke oven battery receiver and in the receiver water decanter are supplied with tar water condensate from gas preliminary coolers and / or water obtained from the separation of benzol and the whole is heated to the temperature at which the water-tar mixture is formed in the coke oven battery receiver and is subjected to separation on a three-phase sedimentation centrifuge, and vapors and gases from the centrifugation process are discharged to the raw gas pipeline. 2. The method according to p. The method of claim 1, characterized in that the amount of tar water condensate and / or water from benzol separation added to the tar before centrifugation is up to 100% by weight in relation to the amount of water contained in the tar before centrifugation.