JPH029905Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention is a dry-type harmful gas absorption electricity that removes HCl, SOx, and other harmful gases contained in exhaust gas from municipal waste incinerators, etc., and captures dust in the exhaust gas. This relates to a dust collector.

Conventional harmful gas absorption devices exist separately from dust collectors, and although they have high gas absorption efficiency, they have high equipment costs and require a separate installation area. Therefore, there was a need for a simple and inexpensive harmful gas absorption system. In response to this demand, a system has been proposed in which absorbent is directly injected into the incinerator and the products are collected by a dust collector, but it is difficult to obtain high absorption performance, and the absorbent itself hinders combustion. There are other problems.

The present invention aims to solve the problems of these conventional techniques and to provide a new device that is simple and does not adversely affect combustion in an incinerator.

It is well known that harmful gases such as HCl and SOx in exhaust gas can be absorbed and fixed by contacting with Ca(OH) ₂ as a harmful gas absorbent.
The harmful gas absorption electrostatic precipitator according to the present invention absorbs and reacts the above harmful gas with Ca(OH) ₂ powder directly injected into flue gas, and produces CaCl ₂ , CaSO ₄ ,
It is characterized by collecting unreacted Ca(OH) ₂ along with reaction product powder such as CaSO ₃ in the suction collecting dust part, and collecting dust at the same time as absorbing harmful gases. It is something to do.

Next, details of one embodiment of the present invention will be explained with reference to the drawings.

Figure 1 shows the entire device, and the device of the present invention includes a conventionally known electrostatic precipitator 1 provided at the last stage, and a suction and collection dust section that traps unreacted Ca(OH) ₂ and gas absorption products. 2. Discharge electrode part 3 provided at the end of the flue or expanded gas flow path (hood part), Ca
(OH) Injection part 4 for injecting gas absorbent such as ₂ ,
It also includes a water spray nozzle 5 and the like.

Powder that reacts with and absorbs harmful gases such as Ca(OH) ₂ is injected into the flue gas from an injection portion 4 into which a harmful gas absorbent is injected. The powder absorbs harmful gases while diffusing in the flow of exhaust gas, and absorbs harmful gases.
Reacts with HCl, SOx, etc. to generate CaCl ₂ , CaSO ₄ , CaSO ₃ , etc. Product particles and unreacted particles after reaction absorption
Ca(OH) ₂ is ionized in the discharge electrode section 3 and trapped in the dust collection section 2.

The trapped unreacted Ca(OH) ₂ reacts again with HCl and SOx remaining in the exhaust gas, resulting in gas absorption.

The discharge electrode section 3 and the dust collection and collection section 2 are collectively referred to as a harmful gas removal processing section.

In addition, since the gas flow is made uniform by appropriate ventilation resistance, the dust collection and collection section 2 can function as a gas rectifier in a normal electrostatic precipitator installed at a subsequent stage. An injection part 4 for injecting the harmful gas absorbent is provided in the flue or its enlarged part, and the Ca(OH) ₂ and harmful gas injected from the injection part 4 are
An absorption reaction takes place between HCl, SOx, etc., and the gas after the absorption reaction reaches the discharge electrode section 3. The water spray nozzle 5 controls the exhaust gas temperature by spraying water, provides appropriate moisture to Ca(OH) ₂ , enhances the charging effect, and also increases the harmful gas absorption effect. Further, the mounting position of the water spray nozzle 5 changes from just before the noxious gas absorbent injection part 4 to just before the suction and collection dust part 2 depending on the situation of peripheral devices.

FIG. 2 shows an example of the discharge electrode section 3 provided in the expanding exhaust gas flow path. The discharge electrode part 3 collects reaction products that have absorbed harmful gases in exhaust gas and unreacted Ca.
(OH) ₂ dust is ionized, and the ionized dust is captured by the suction/collection part 2. Further, the discharge electrode part 3 is suspended by a high voltage insulator 7, and a discharge electrode frame 9 is electrically insulated from the casing.
A plurality of discharge elements 8 are attached to the discharge elements 8, and when dust passes between the discharge elements 8, it is ionized. The discharge element 8 includes wires of various shapes,
It is possible to use a plate, rod, net, etc., and an electric field is formed with the suction collecting dust part 2 behind the gas flow.

Figure 3 shows the suction and collection part 2, where the metal ball 1
2, or arrange balls whose surfaces have been treated with good conductivity,
The gas flow cross section shall be partitioned uniformly. Unreacted Ca(OH) ₂ attached to this metal sphere is further converted into HCl,
Absorbs and reacts with unreacted harmful gases such as SOx. The screen 13 protects the filling of the sphere,
The same goes for the back side. By opening the lower part, the spheres packed in layers are moved sequentially from top to bottom. In order to adjust this, an adjustment plate 14 is provided to control the amount of fall of the sphere. Screw conveyor 15
is to send the fallen sphere to a lifting device 16.At this time, most of the dust attached to the surface of the sphere is peeled off, so the powder is separated by a powder sorter 17 and discharged out of the system, and the sphere is removed from the top. It is filled again and moved to the bottom.

Thus, in the harmful gas removal processing section, the harmful gas absorbent is injected into the flue according to the present invention, and the harmful gas is absorbed and reacted with the harmful gas to remove the product particles and unreacted.
Collected unreacted Ca(OH) ₂ can be re-reacted and used effectively so that Ca(OH) ₂ can be ionized in the discharge electrode section and captured as particles in the dust absorption/collection section along with dust. Can be done.

As described above, the present invention simultaneously solves the respective problems of electrostatic precipitators and harmful gas removal processing equipment, and also reduces equipment costs when using both electrostatic precipitators and harmful gas removal processing equipment. This also solves the problems of soaring prices and expansion of equipment space. Furthermore, in the reaction between the noxious gas and the noxious gas absorbent, the present invention not only performs the conventional contact reaction based on mere physical diffusion, mixing, and collision, but also applies a high voltage at the discharge electrode. The present invention provides an extremely simple device that has the advantage that the reaction between the reacted harmful gas and the unreacted harmful gas absorbent is particularly promoted on the surface of the metal sphere in the dust collection section, further increasing the removal efficiency of the harmful gas. .

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the device of the present invention;
FIG. 2 is a perspective view of a harmful gas removal processing section provided at the front stage of a known electrostatic precipitator 1, and FIG. 3 is a perspective view of a suction and collection dust section 2. In the figure, the symbols of the main parts of the present invention are as follows. 1...Known electrostatic precipitator, 2...Sucking dust collecting section,
3... Discharge electrode part, 4... Harmful gas absorbent injection part, 5... Water spray nozzle, 7... High pressure insulator,
8...Discharge element, 9...Discharge electrode frame,
12...Metal ball, 13...Screen, 14...
Adjustment plate, 15... Screw conveyor, 16...
Device for lifting balls, 17...powder sorter.

Claims (1)

[Scope of Claim for Utility Model Registration] A device for removing harmful gases and dust from exhaust gas containing harmful gases and dust; (b) A harmful gas removal processing unit connected to the outlet end of the flue and consisting of the following composition, consisting of at least one material consisting of a group of wires, plates, rods, and nets attached to an insulated discharge electrode frame. A discharge electrode section in which a discharge element is attached perpendicular to the gas flow direction and over the entire surface of the gas flow path, and the front and back surfaces of the discharge electrode section, which are attached to the rear of the discharge electrode section and cover the entire surface of the exhaust gas flow path, are protected by a screen. a filling layer of metal balls or balls whose surfaces are treated with good conductivity, which move from top to bottom and whose lower part is open; a regulating plate provided below the open lower part of the filling layer; a screw conveyor; A device for lifting a metal ball or a ball whose surface has been processed to have a good conductivity to the top of the packed bed; a powder sorter; and a dust collection section consisting of a powder discharge path; c. At the rear of the harmful gas removal processing section, a known A harmful gas absorption electrostatic precipitator consisting of a dust removal processing section equipped with an electrostatic precipitator.