JPS6112790A - Jet bed coal gasification furnace - Google Patents

Abstract

PURPOSE:To reduce the amount of char flying from a gasification part to a gas cooling part, by means of a cylinder, provided in the upper constricted part of the gasification part in the boundary part of the gasification part and the gas cooling part, and having the lower end protruding into the gasification part. CONSTITUTION:A jet bed gasification furnace having a cylinder 15, e.g. made of ceramics, provided in the upper constricted part 11 of a gasification part 1, and having the lower end 16 protruding into the gasification part 1 by a length (S). A swirling current in the upper part of the gasification part 1 is kept and continued, and powdered coal is pressed to a refractory wall 14 of the gasification part 1 by the centrifugal force to flow down along the refractory wall 14. Thus, the powdered coal is separated from the rising current of the coal gas, and the flying thereof from the gasification part 1 to the gas cooling part 2 is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a spouted bed coal gasifier, and particularly to a spouted bed coal gasifier with high gasification efficiency and high cold gas efficiency.

Cold gas efficiency is the ratio of the heat content (calorific value) of produced gas at low temperature to the heat content of supplied coal.2 A coal gasifier whose purpose is to obtain gas fuel from coal has cold gas efficiency. It is desirable that the

[Background of the invention]

Figure 4 is a schematic diagram of a conventional spouted bed coal gasifier;
FIG. 5 is a sectional view of the gasification section of a conventional spouted bed coal gasifier.

In Fig. 4 and Fig. 5, "Entrained bed coal gasifier 1"
3 is composed of a gasification section 1 and a gas cooling section 2. The gasification section 1 is constructed of a refractory wall 14 that is cooled and protected by a water-cooled wall tube 10, and has an upper constriction section 11 at the boundary with the gas cooling section 2, and a coal ash discharge section at the bottom. A slag tap port 12 is provided in each case.

Pulverized coal supplied from the coal supply facility 4 is conveyed by an inert gas such as N2, and is supplied to the gasification section 1 by a coal supply burner 8 together with O2 generated from the gas and other agent generating device 3. A part of the pulverized coal supplied by the two-coal supply burner 8 in the gasification section 1 is combusted by the gasifying agent 0□, and the combustion heat converts C in the remaining unburned pulverized coal to co. Also, hydrogen content becomes H2.

They are each gasified to generate coal gas consisting of Go, H2, H, O, and Go□.

The coal gas generated in the gasification section 1 is cooled to approximately 1000°C in the gas cooling section 2, and the ash and unreacted carbonaceous substances (char) in the coal gas are lowered to a temperature below the melting point, and then sent to subsequent equipment. The adhesion of the product disappears.

The coal gas that has lost its adhesive properties passes through a heat recovery device W5, char is collected in a dust collector 9, and passes through a gas purification device 6 to become a generated gas. The char collected in the dust collector 9 is transported by an inert gas such as N2, and is supplied to the gasification section 1 by the coal supply burner 8 and recycled.

In order to improve coal gasification efficiency, it is important to lengthen the residence time of the pulverized coal in the gasification section 1 to gasify as much carbon and elements in the pulverized coal as possible.

Therefore, the ejection direction of the two coal supply burners 8 is inclined from the radial direction to the circumferential direction of the gasification section 1, and the pulverized coal and 02 are supplied by the two coal supply burners 8.

It is configured to rotate within the gasification section 1. Also.

The number of coal supply burners 8 is increased to supply pulverized coal in multiple stages, and as already explained, an upper constriction section 11 is provided at the boundary between the gasification section 1 and the gas cooling section 2.

In this way, the residence time of the pulverized coal in the gasification section 1 is lengthened, but the pulverized coal, which has become more atomized or lighter due to gasification, is accompanied by the coal gas generated in 2. and scatter into the gas cooling section 2, or
After descending due to the swirling flow in the gasification section 1 and reaching the bottom, it is scattered to the gas cooling section 2 along with the upward flow. Furthermore, there is pulverized coal that is supplied by the two coal supply burners 8 and scattered to the gas cooling section 2 along with the upward flow without being gasified. The amount of these chars scattered from the gasification section 1 to the gas cooling section 2 is 30 to 4 times the amount of pulverized coal supplied.
This scattered char is collected by the dust collector 9, recycled to the gasification section 1, and gasified again.

By recycling the scattered char, the gasifier 1
As the load of No. 3 increases, the amount of inert gas that transports the scattered char reaches 3 to 5% of the amount of generated gas. Therefore, the calorific value of the generated gas decreases by 3 to 5%, and the calorific value of the generated gas is used for preheating the inert gas, so the cold gas efficiency decreases by 1 to 2%. Therefore, reducing the amount of scattered char has traditionally been a problem.

[Purpose of the invention]

This invention provides a spouted bed coal gasifier with high cold gas efficiency by reducing the amount of char scattered from the gasification section to the gas cooling section, thereby reducing the amount of inert gas conveying recycled char. The purpose is to

[Summary of the invention]

In this invention, a cylinder is provided in the upper constriction part of the gasification part at the boundary between the gasification part and the gas cooling part, and the lower ends of the two cylinders are made to protrude into the gasification part. This method is characterized by reducing the amount of char.

[Embodiments of the invention]

FIG. 1 is a sectional view of the gasification section of the spouted bed coal gasifier of the present invention, and FIG. 2 is a diagram showing the collection efficiency of pulverized coal in the gasification section of the spouted bed coal gasifier of the present invention.

FIG. 3 shows the gasification section of the spouted bed coal gasifier of the present invention. 1 is a diagram showing a spouted bed coal gasifier without a dust collector; FIG.

In FIGS. 1 and 2, a cylinder 15 made of ceramic or sintered metal is provided in the upper constricted part 11 of the gasification section, and the lower end 16 of the cylinder 15 protrudes into the gasification section 1 by a length S. I'm letting you do it. By projecting the lower end 16 of the cylinder 15 inward by a length S into the gasification.

Since the swirling flow in the upper part of the gasification section 1 is maintained and continued, the pulverized coal flows through the refractory wall 1 of the gasification section 1 due to centrifugal force.
4, flows down along the refractory wall 14 and is separated from the upward flow of coal gas, preventing it from scattering from the gasification section 1 to the gas cooling section 2.

Fig. 2 shows the height L of the gasification section 1 and the protrusion length S of the cylinder 15.
to the ratio S/L. The collection efficiency of pulverized coal during the cold test and the collection efficiency obtained by converting the collection efficiency during the cold test during gasification are shown. As shown in FIG. 2, since the collection efficiency during gasification ranges from 80 to 90%, the amount of scattered char is 10 to 20% of the amount of pulverized coal supplied. Conventionally, the amount of scattered char is 30~30% of the amount of pulverized coal supplied.
According to the present invention, the amount of scattered char can be reduced to 1/2.

In addition, since the amount of scattered char is reduced by this invention, the dust collector of the spouted bed coal gasifier can be eliminated, as shown in FIG. That is, the generated coal gas is introduced into the gas purification device 6 via the heat recovery device 5, and the scattered char is removed by the wet gas cleaning equipment in the gas purification device 6.

It becomes a generated gas.

〔Effect of the invention〕

As explained above, according to the present invention, the amount of char scattered from the gasification section to the gas cooling section is reduced to 1/2 of the conventional amount, so the amount of inert gas for conveying recycled char is reduced. therefore.

The calorific value of coal gas is 1 to 2%, and the cold gas efficiency is 0.
There are effects that can improve the results by 3 to 0.6%. Furthermore, the dust collector can be omitted, which has the effect of simplifying subsequent equipment.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the gasification section of the spouted bed coal gasifier of the present invention, and FIG. 2 is a diagram showing the collection efficiency of pulverized coal in the gasification section of the spouted bed coal gasifier of the present invention. FIG. 3 shows the gasification section of the spouted bed coal gasifier of the present invention. Figure 4 shows an outline of a conventional spouted bed coal gasifier; Figure 5 shows a conventional spouted bed coal gasifier gasifier. FIG. 1... Gasification section 2... Gas cooling section 3...
・Gas and other agent generators 4...Coal supply equipment 5...Heat recovery device 6...Gas purification device 7...Slag extraction hopper 8...Coal supply burner 9...Dust collector 10 ...Water-cooled wall tube 11...Top constriction section
12...Slag tap port 13...Entrained bed coal gasifier

Claims (1)

[Claims] A constriction part is provided at the boundary between the gasification part and the gas cooling part above the gasification part, and the coal and the gasification agent are supplied to the gasification part, and the coal and the gasification agent are supplied to the gasification part. In the spouted bed coal gasifier that generates coal gas from the coal in the gasification section by swirling the coal and the gasification agent, a cylinder is installed in the constriction section, and a lower end of the cylinder is made to protrude into the gasification section. Characteristics of the spouted bed coal gasifier.