JPS58205555A - Cyclone separator - 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 This invention relates to the gasification of carbon-containing materials, and more particularly to an apparatus for removing entrained particles from the product gas of a fluidized bed gasification reactor.

Reactors used for the gasification of carbon-containing materials such as coal produce not only combustible product gases but also solid waste products such as agglomerated ash. The process development unit (PDU)'s experimental fluidized bed gasification reactor currently in operation for the U.S. government consists of a vertical pressure vessel with a fluidized bed inside, a vertical pressure vessel with a plurality of Granular coal is introduced into one of the concentric tubes. The fluidization phenomenon occurs in its upper part.

In PDLI's fluidized bed gasification reactor, the gasified coal product gas contains a significant amount of entrained particles, most of which are present at gasifier outlet temperatures between 930°C and 1040°C;
It is typically in a molten state at approximately 980°C. These particles, which have different chemical compositions, adhere to non-metallic as well as metallic surfaces as they exit the gasifier outlet, regardless of the angle of impingement of the gas stream on that surface. It has been found that this will eventually clog the flow passages with solidified material and the efficiency of the cyclone separator will be reduced accordingly.

According to the experimental data obtained as a result of the operation of the PDU and the information presented in various technical reports, if the following two
It has been found that these molten particles do not accumulate upon exiting the gasifier if either of the following conditions are met:

fa) Gas temperature does not exceed 705℃ (bl
The surface through which the gas passes or collides is metal, and the temperature of the gas-metal interface surface is maintained at 260°C or less.

Condition (a) is satisfied by water spray quenching, but this method is energy inefficient under certain operating conditions.

Condition (b) is achieved by water cooling a non-thermally insulated metal surface, but the erosion of the metal plate is significant and requires special care for the differential pressure on both sides of the metal plate.

Thus, the main object of the present invention is to provide a gasifier cyclone that can be operated for a long period of time without repair or security because there is little accumulation of entrained particles and there is no need to lower the temperature of the slag.
The purpose is to provide separators.

According to one embodiment of the invention, a cyclone separator for separating entrained particles from a first gas is arranged to separate an outer casing from the outer casing so as to define a cavity between the outer casing and the outer casing. a porous interior casing spaced apart and defining an interior plenum space; a first tangential gas introduction means for introducing the first gas into the interior plenum space; and a first tangential gas introduction means for discharging the particles from the interior plenum space. particle evacuation means;
a second gas introduction means provided in the outer casing for introducing a second gas into the cavity at a higher pressure than the first gas, the second gas being introduced into the porous inner casing; It is characterized in that it is forcibly introduced into the internal plenum space through.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Referring to FIG. 1, the cyclone separator 20 is disposed so as to tangentially penetrate the outer casing 22, the porous inner casing 24 disposed inside the outer casing 22, and the outer casing 22 and the inner casing 24. product gas population 26, outer casing 22 and inner casing 24 at the top of the cyclone separator 2o
The product gas outlet L128 is arranged to penetrate through the outer casing 2 at the bottom of the cyclone separator 20.
2, a particle outlet 30 disposed to penetrate the inner casing 24, and a cooling gas inlet 32 disposed to penetrate the outer casing 22. A cavity 34 is formed between inner casing 24 and outer casing 22 and an internal plenum space 36 is formed within inner casing 24 . The porous inner casing 24 may be made of a corrosion resistant material such as Inconel or refractory ceramic. For example, it may be made of a naturally porous material such as refractory ceramino, or the metal may have a plurality of holes formed therein to allow gas to pass through.

To explain the operation of the cyclone separator 20,
A gas containing entrained particles, such as a product gas from a carbon-containing material gasifier containing solid entrained particles in a molten state, is introduced tangentially into the interior plenum space 36 via the product gas population 26. . Since the gas is rotationally coupled within the interior space 36, the entrained particles collide with the inner casing 20+. As a result, the velocity of the entrained particles decreases and they fall towards the bottom of the internal plenum space 36 from where they are ejected via the particle outlet 30.

During operation, the pressure is lower than that of the product gas (typically about 6 - 0.07 Kg/r, 0.5 Kg/r).
The cooling gas, which is higher than d) l, is used for cooling purposes [13
2 into the cavity 34. This gas is transpired through a plurality of holes or holes distributed throughout the inner casing 24 and oriented generally downwardly toward the center of the plenum space 36.
ation) + more porous inner casing 24
move inward. The temperature of the cooling gas is 24℃ to 66℃
, typically about 38°C, and this gas cools the temperature of the inner casing 24 to about 204°C.

The product gas, free of large amounts of entrained particles, is removed from the internal plenum space 36 via the raw gas outlet 28.

With reference to FIGS. 3 and 4, the cooling caused by the divergence action is as follows:
Cooling fluid 40 is present in the porous inner casing 24 through a number of holes 40 (or through a material having a number of holes 44).
4 gives a very large heat transfer area/coolant flow rate ratio. Some of the benefits of utilizing industrial cooling include: (1) reduced entrained particles depositing on the porous inner casing 24 of the cyclone separator 20; (3) porous inner casing 24, the temperature of the gas is less affected;
The thickness can be reduced.

Using a cooling method based on divergence, the temperature of the porous inner casing 24 can be maintained at around 204°C.

As a result, deposition of entrained particles hardly occurs.

Because the cooling fluid 4.0 is in intimate contact with the porous inner casing 24, only a small amount of cooling fluid 40 is required to achieve the desired cooling effect. Thus, the temperature of the product gas is
Since there is no need to add a large amount of cooling gas, it is not affected much.

Because the porous inner casing 24 is continuously cooled, it is not subjected to extremely large thermal strains and is thinner than it would be without cooling. This reduces the cost, manufacturing complexity, and repair or replacement cost of the porous inner casing 24.

The details of the hole dimensions, the surface laziness of the pores (the number of holes per unit surface area of the inner casing 24) or the porosity of the material are as follows:
It is necessary to determine the required cooling characteristics based on the number of cooling characteristics required. Factors such as the roughness and diameter of the cyclone separator 20, the temperature and loading of the product gas, the temperature and flow rate of the cooling fluid 40 will determine the required cooling capacity. influence This in turn affects the dimensions of the holes and the size of the heat transfer surface, which is the basis for determining the surface density of the holes or the porosity of the material.

In a preferred embodiment of the invention, the cooling fluid 40 is used to cool and remove substantially all entrained particles.
The product gas that had been processed by the above steps was used. An advantage of this method is that the product gas from the cyclone separator 20 does not undergo chemical changes, since no cooling gas with other chemical composition is added.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a cyclone separator according to one embodiment of the present invention; FIG. 2 is a plan view taken along line 2--2 of FIG. 1; FIGS. FIG. 20... Cyclone separator; 22... Outer casing; 24... Porous inner casing; 26...
・Product waste 1.1; 2 g...Product gas output [1; 30...Particle output 11

Claims (1)

[Claims] 1. Cyclone that separates entrained particles from the first gas
in the separator, an outer casing; a porous inner casing spaced apart from the outer casing to define a cavity within the outer casing and defining an inner plenum space; first tangential gas introduction means for introducing a first gas between the internal plenum spaces; particle evacuation means for ejecting the particles from the internal plenum space; a second gas introduction means provided in the outer casing for introducing the first gas at a higher pressure than the first gas, the second gas being forced into the inner plenum space through the porous inner casing; A cyclone separator characterized by: 2. The cyclone separator 0 according to item 1, wherein the first gas is a generated gas from a carbon-containing material gasifier d, and the particles are entrained particles from the gasifier. 3. The cyclone separator according to item 1 or 2, wherein the second gas has a lower temperature than the first gas. 4. The second gas is a clean gas containing substantially no particulate matter.
Or the cyclone separator described in item 3. 5. The cyclone separator according to any one of items 1 to 4, wherein the second gas is of the same type as the first gas. 6 The temperature of the first gas is between 930°C and 1040°C, and the temperature of the second gas is between 24°C and 6-6°C. Cyclone separator described in any one of the items. 7. The cyclone separator according to any one of the items 1 to 6, wherein the pressure of the second gas is 0.07 to 1.05 Kq/t4 higher than the pressure of the gas of the curved line 1. . 8. The cyclone separator described in any one of items 1 to 7 above, wherein the porous material is made of a refractory ceramic material. 9. Any one of items 1 to 7 above, wherein the inner casing has a wall with a plurality of holes formed therein.
Cyclone separator described in section.