JPS5835734B2 - Combustion gas processing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a combustion gas processing device for removing dust and harmful components from combustion gas.

For example, combustion gas emitted from boilers, steel plants, chemical plants, etc. contains large amounts of harmful components such as sulfur dioxide gas, chlorine, hydrochloric acid, and nitrogen oxides, as well as large amounts of dust, which causes pollution. It has become.

Venturi scrubber type processing equipment is frequently adopted as a means of separating this large amount of harmful components and dust from combustion gas. A chemical solution is supplied and a mixed flow of the chemical droplets and exhaust gas is blown into the processing solution to promote gas-liquid contact and further purify the combustion gas.

In this case, in order to increase the flow velocity of the mixed flow at the outlet end of the venturi scrubber and to promote blowing into the processing liquid, a conical guide is installed inside the outlet end of the venturi scrubber, as in the invention of JP-A No. 48-41974. Some have their tops fixed to the throat of the Venturi scrubber, forming a narrow annular injection port (gas passage).

However, this device has a problem in that only a single cylindrical gas flow is obtained and it is not possible to effectively contact the absorption liquid.

The present invention seeks to rectify such conventional deficiencies.
The purpose is to maintain the gas flow velocity at the desired appropriate value at the outlet end of the venturi scrubber, and to form a double hollow cylindrical gas flow that enters the processing liquid, thereby doubling the effect of gas-liquid contact. Therefore, it is an object of the present invention to provide a combustion gas processing device which can more effectively remove harmful components and dust and which is compact.

In short, this invention treats and cleans combustion gas containing dust and harmful components, and the outlet end of a venturi scrubber is provided with a cone and a cone ring with a triangular peripheral section to form a double annular gas passage. By passing the processing gas through the passageway to form a double cylindrical gas flow velocity and adjusting this flow velocity to a desired value, it is possible to increase the area of gas-liquid contact and reduce the bubbles formed in the processing liquid. This is intended to increase dust removal and reaction.

An embodiment of the present invention will be described below with reference to the drawings, taking as an example the case where the venturi cross section is circular.

1 is a combustion gas inlet duct, 2 is a combustion gas processing device (hereinafter simply referred to as the device), 3 is a partition plate, 4 is a venturi scrubber supported by the partition plate 3, and 5 is a nozzle provided at the outlet of the venturi scrubber 4. The nozzle member 5 is formed by a conical body 5a, a conical ring 5b, and a fixture 7.

6ay6b is a conical body 5a, a conical ring 5b, and a conical ring 5b
and an annular gas passage formed by the outlet opening end 4a of the Venturi scrubber 4.

In a device with such a structure, the combustion gas flows through the inlet duct 1.
The combustion gas is supplied from the inside to the venturi scrubber 4, where the combustion gas is cooled and primary gas treatment is performed by spraying from the treatment liquid injection nozzle 13 and the water injection nozzle 15. Thereafter, a second gas treatment is performed using the treatment liquid from the injection nozzle 14.

Next, the gas flow that has become double cylindrical at the outlet of the venturi enters the treatment liquid 12 of the combustion gas treatment device 2, and the absorbed combustion gas is reversed to the cleaning packed bed 17a and the discharge passage 16.
, water droplets are removed by the mist separator 17b, and the gas is exhausted from the exhaust gas outlet duct 18.

FIG. 2 is a longitudinal cross-sectional view of the outlet end of a venturi scrubber showing an embodiment of the present invention, and FIG. 3 is a cross-sectional view taken along the line AA in FIG. 2.

As shown in the figure, a nozzle member 5 is provided at the outlet of the Venturi scrubber 4 to form a double cylindrical gas flow through a double annular gas passage, and adjust the gas flow rate to a speed suitable for entering the processing liquid 12. It is set to .

As shown in the figure, the combustion gas in the venturi scrubber 4 is divided by the conical body 5a and the conical ring 5b. Therefore, when comparing venturi scrubbers having outlet ends with the same inner diameter, for example, in the invention of JP-A-48-41974, the combustion gas is separated by the conical body 5a and the conical ring 5b. In contrast, in the illustrated apparatus according to the present invention, a double cylindrical waste flow is obtained, so that the opportunity for gas-liquid contact with the processing liquid 12 is as low as 100%. This doubles the number of bubbles formed, making reaction and dust removal more effective.

In the conventional example disclosed in Japanese Patent Application Laid-Open No. 48-41974,
The only way to increase the gas-liquid contact area is to increase the inner diameter of the outlet end of the venturi scrubber, but this increases the length of the venturi scrubber.

This is because the angle of divergence at the exit side of the venturi scrubber has a certain optimum angle in order to reduce fluid flow loss.

Therefore, increasing the inner diameter of the outlet end is an inappropriate means for making the device compact.

By carrying out this invention, a double cylindrical gas flow is formed at the outlet of the venturi, and the cross-sectional area of the double annular gas passage is set so that the gas flow velocity is appropriate. This doubles the chances of gas-liquid contact, increasing the effectiveness of harmful gas removal and dust removal, and also reduces the overall size of the device by reducing the height and diameter of the Venturi. be.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a device showing an embodiment of the present invention, FIG. 2 is an enlarged sectional view of the main part of FIG. 1, and FIG. 3 is a sectional view taken along the line A-A in FIG. 2. . 1... Inlet duct, 2... Combustion gas processing device, 3... Partition plate, 4... Venturi scrubber, 4a... Outlet opening end, 5.
...Nozzle member, 5a... Cone, 5b
......Conical ring, 5a, 5b...Annular gas passage, 7...Fixing metal fittings.

Claims (1)

[Claims] 1- In a combustion gas processing device in which a number of venturi scrubbers or more are provided, a cone is provided coaxially with the outlet end of the venturi scrubber located close to the processing liquid level and fixed in a relative position; A conical ring with a triangular peripheral section is provided between the outlet end and the conical body to form a double gas passage, and the gas flow rate of the double cylindrical gas flow through this passage is formed to a desired value. A combustion gas processing device characterized by: