JPH03220292A - Method for removing sludge from tar - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for centrifuging crude tanyl obtained by carbonization of coal or the like to separate sludge.

[Prior Art] When coal is carbonized, various byproducts are obtained, one of which is tar. When the gas generated from the coke oven is first sprayed with ammonium water (Garth liquid) to neutralize and cool it, the tar liquefies. Crude tar is separated from this mixture of tar and ammonium water by sedimentation and separation in a tar decanter, but this crude tar contains sludge. Therefore, this crude tar is further centrifuged to remove the sludge and become a product tar. Conventionally, the above-mentioned crude tar has been made into a product by simply performing one stage of centrifugation.

[Problem to be solved by the invention]

Fine sludge particles remained in the product tar obtained above, and moisture entered the sludge, reducing the quality of the product tar.

An object of the present invention is to increase the separation rate of the sludge and improve the quality of the tar product.

[Means to solve the problem]

The present invention has been made to achieve the above-mentioned objects, and includes cooling gas generated from a coke oven, separating gas liquid from the resulting mixture of tar and gas liquid to obtain crude tar, and producing crude tar. In this method, a part of the tar discharged from the centrifuge is collected as refined tar, and the remainder is mixed with crude tar and centrifuged again. This invention relates to a method for separating sludge in tar, which is characterized by connecting two or more centrifuges in series and further centrifuging the tar discharged from one centrifuge in the next centrifuge. be.

There are many types of centrifuges, including cylindrical, separator, and decanter types, and any of them can be used.

A portion of the tar discharged from the centrifuge is collected as refined tar, and the remainder is mixed with crude tar and centrifuged again. The remainder may be returned to the crude tar tank, but in order to quickly increase the degree of purification, an intermediate tank between the water tanks may be provided and the crude tar may be mixed there, or the liquid may be sent by connecting the crude tar tank and the centrifugal separator. It is preferable to provide a branch part in the middle of the pipe so that the crude tar joins there. The amount of circulation is determined by the properties of the crude tar, the capacity of the centrifuge, the quality required of the refined tar, etc., and is usually about 30 to 70%, preferably about 40 to 50%.

The sludge removal rate can be further increased by using two or more centrifuges connected in series. Approximately 2 to 4 centrifuges are connected in series.

By combining the series operation and circulation described above, the sludge removal rate can be further increased.

In the method of the present invention, it is preferable to heat the tar to lower its viscosity. Heating may be done outside the centrifuge (or a heating mechanism may be attached to the centrifuge. If heating is done outside the centrifuge, the liquid feed pipes, circulation lines, and centrifuge lines to the centrifuge may be heated). You can heat the connecting lines between the pipes from the outside, or install heaters on these pipes.On the other hand,
If a heating mechanism is attached to the centrifuge, the rotor,
＼Heating may be done from either side of the housing, and any heating means may be used; steam, hot air, electricity, etc. can be used. The appropriate heating temperature is such that the tar reaches 60 to 150°C, preferably 80 to 100°C.

Examples of application of the method of the present invention are shown in FIGS. 1-3. FIG. 1 shows an example in which a portion of the tar discharged from a centrifuge is circulated to a crude tar feed line, and FIG. 2 shows an example in which two centrifuges are connected in series.

Further, FIG. 3 shows an example in which two centrifugal separators are connected in series and a new line is provided to circulate part of the tar discharged from the first centrifugal separator to the first centrifugal separator.

[Effect]

Currently, the value of product tar is determined by the tar moisture value in the product tar. It is thought that the tar moisture is caused by the entrainment of moisture by the sludge contained in the coolant. Therefore, the more this sludge is removed, the lower the moisture value in the tar will be.

In the method of the present invention, by passing tar through a centrifuge multiple times, it is possible to remove sludge of 200 mesh or less by 80% or less compared to the conventional method.

〔Example〕

Example 1 Two horizontal decanter type centrifuges were installed in Figure 1 or Figure 2.
It was used in the form shown in the figure.

In the separation and purification equipment for gas generated from coke ovens,
The amount of crude tar flowing out from the tar decanter is 20 to 3
It contained 0% moisture and the temperature was 55°C. This crude tar with a moisture content of 20% was heated to 80°C and centrifuged as shown in Figure 1, with a circulation rate of 50%, resulting in a moisture content of 4.3%.

Furthermore, when two units were connected in series and centrifuged as shown in Figure 2, the water content was 2.0%. In the above, a ribbon heater was wrapped around the circulation line and the connection line to heat the tar to 100°C. On the other hand, when the material was heated to 80°C and passed through one centrifuge, the moisture content was 7.0%.

Example 2 Crude tar with a moisture content of 30% was treated in the same manner as in Example 1. In the case of the circulation system, the moisture content was 4.3%, in the case of the series system, the moisture content was 1.6%, and when treated with only one unit, the moisture content was 4.3%. 7.7
% respectively. We measured the sludge content of centrifuges using a serial system and a single centrifuge, and obtained the results shown in the table below.

Single unit processing Series processing 200 mefshieon 0.432g/300
g 0.034g/300g 100mefshieoshi 0.032g/300g 0.01
5g/300g [Effects of the Invention] According to the method of the present invention, particularly minute sludge can be efficiently removed and the moisture content of product tar can be greatly reduced.

[Brief explanation of drawings]

1 to 3 all show examples of embodiments of the present invention.

Claims (2)

[Claims] (1) Cool the gas generated from the coke oven, separate the gas liquid from the resulting mixture of tar and gas liquid to obtain crude tar, and centrifuge the crude tar to separate the sludge contained therein. A method for removing sludge from tar, which is characterized in that a part of the tar discharged from a centrifuge is collected as refined tar, and the remainder is mixed with crude tar and centrifuged again. (2) Cool the gas generated from the coke oven, separate the gas liquid from the resulting mixture of tar and gas liquid to obtain crude tar, and centrifuge the crude tar to separate the sludge contained therein. A method for removing sludge from tar, characterized in that two or more centrifuges are connected in series, and the tar discharged from one centrifuge is further centrifuged in the next centrifuge.