DE102009019966A1 - Suspended particle gasifier has partial quenching chamber above quench tank, with gas outlet geometry separating entrained particles ahead of waste heat recovery boiler - Google Patents

Abstract

A cooling chamber (2) under the gasification reactor (1) has a water bath below its lower end. The gasification reactor discharges into a tubular quenching unit (D) within the quenching chamber, via a raw gas- and slag outlet (A). The quenching unit surrounds a quenching chamber (4). The quench chamber cross section does not reduce in the direction of flow. Nozzles (C) arranged in this chamber, spray quenching water. A raw gas outlet (F) is located in the pressure casing containing the cooling chamber. The lower edge of the outlet (F) lies above the lower edge of the cooling unit (D).

Description

The The invention relates to a device for quenching in an entrained flow gasifier produced raw gas from the gasification of ash-containing feedstocks.

In the future, new demands will be placed on fossil-fueled power plants, such as lowest emissions and additional CO ₂ separation. The currently most advanced power plant concept for CO ₂ separation is the Integrated Gasification Combined Cycle (IGCC). This technology involves gasification of the fuel before the actual gas and steam power plant (CCGT). Since CO ₂ capture measures are always associated with a loss of efficiency (8% -12%, depending on the technical boundary conditions), it is important for the realization of an IGCC system to strive for a high degree of efficiency for the individual sub-processes.

One possible process that may be upstream of the combined cycle power plant is the Siemens Fuel Gasification process, which is protected under the trademark SFG method. This autothermal entrained flow gasification process is suitable for the use of ash-rich solid, liquid and gaseous feedstocks. The feedstock is reacted in a flame reaction, at temperatures (1500 ° C-1800 ° C) above the ash melting temperature, to give CO and H ₂ (major synthesis gas components). The hot raw gas and the molten slag leave the reactor in the directly vertically below quencher, in which by means of full quenching both the raw gas, and the slag to about 200 ° C-250 ° C are cooled. The slag granules formed by the rapid cooling accumulates in the quencher and is discharged. The cooled gas is passed laterally out of the quencher and fed to the purification stages.

at A process concept with full quenching is the high temperature level the hot raw gas for the production of steam can not be used.

The Use of sensible heat for steam generation is for example in an IGCC application with cogeneration conceivable and would in this context a possibility represent the increase in efficiency.

From the EP 0870818 A2 a gasification device is known in which a cone narrows the cross section of the quench chamber, so that the raw gas with high acceleration impinges on the water bath and thus to be cleaned of solids and liquid droplets.

at a gasification process with partial quenching can in a subsequent Heat recovery steam generator heat energy can be harnessed, however, partial quenching is compared to full quenching a fundamentally higher ash content of the raw gas.

Of the Invention is based on the problem, a Flugstromvergaser to create a partial quenching with an increased deposition of particles connects.

The Problem is exhibited by a Flugstromvergaser with Teilquench the features of claim 1 solved.

The Invention allows the use of tactile Heat of the hot raw gas.

The Design of the Teilquenchers significantly reduces the dust load of the raw gas, thereby reducing the pollution and slagging of a subsequent heat recovery steam system is reduced and thus the Travel times can be significantly increased.

The positive properties of the dust separation of the invention Part quenching come for a gasification process especially when combined with a heat recovery steam generator system which, in turn, causes increased dust separation caused by the raw gas.

advantageous Further developments of the invention are in the subclaims specified.

The Invention will be described below as an exemplary embodiment To an extent necessary for understanding on the basis of a Figure explained in more detail. Showing:

1 schematic representation of the quench device according to the invention.

An entrainment gasifier is equipped with a top gasification reactor 1 , the head side, the gasification media feedstock, fuel gas for the pilot burner, oxygen and steam are supplied, a separated via an intermediate floor Z, arranged below cooling space 2 and a water bath E1 located at the lower end. The height of the cold room extends between the surface of the water bath E1 and the intermediate floor. The gasification reactor 1 , the cooling space and the water bath E1 are enclosed by a substantially cylindrical pressure jacket.

The reaction of the ash-containing feedstock takes place in the gasification reactor 1 in a flame reaction at temperatures above the ash melting temperature. The hot gasification gas / raw gas and the molten slag flow out of the gasification reactor ( 1 ) over the slag drain body (A) and the draft tube (B) into a quench body (D). The quench body arranged in the cooling space is designed as a tubular, extended extension to the guide tube (B) and encloses a quench chamber 4 , In the quench body, a plurality of quench nozzles (C) are arranged, which inject quench water into the quench chamber radially to the central axis. In the quench chamber, the hot raw gas and the molten slag are cooled to a temperature level of about 900 ° C-950 ° C by means of water injection (partial quenching). The cross section of the quench chamber is designed so that it remains the same in the flow direction of the raw gas until the transition to the cold room, possibly enlarged. The quench chamber ( 4 ) thus has a cross-section, which does not shrink in the flow direction of the raw gas. The lower edge of the quench body (D) may end below the middle of the height of the cooling space. The crude gas outlet F is arranged in the pressure jacket delimiting the cooling space such that the lower edge of the crude gas outlet is positioned above the lower edge of the quench body (D).

The Design of the cold room with the constant cross section having quenching chamber and positioning of the raw gas outlet F with its lower edge above the lower edge of the Quenchkörpers (D) causes the partially-quenched raw gas forcibly over the surface of the water bath is guided and only after it has risen again, the refrigerator below Separation of entrained particles in the water over leaves the crude gas outlet.

The forming slag granules collect in the water bath at the lower end of the cold room ( 2 ) (E1) and is discharged via the slag discharge (H1). The mass transfer in the water bath (E1) of the partial quench ( 2 ) is conveyed by a flow in the direction of Schlackeaustrags (H1). This is done by circulation of water between the Schlackeaustrag (H1) and the Schlackewasserzuführung (G1).

The separation of entrained particles is on the one hand by the water injected in the partial quenching and on the other hand by the enlargement of the flow area in the cold room ( 2 ) realized. By enlarging the area through which the gas flows, the velocity of the (partially) quenched raw gas is reduced to such an extent that further separation (gravitational separation) of entrained particles occurs. This is enhanced in the vaporous boundary layer between the water surface and the gas space by the fact that the dust particles are wetted and deposited more strongly due to the increased mass. The improved separation in the boundary layer in turn is due to the forced guidance of the raw gas via the water bath (E1) of the refrigerator ( 2 ). Due to the rising of the raw gas to the raw gas outlet (F) dust is increasingly deposited, which sinks into the water bath. The hot raw gas leaves the cold room ( 2 ) via the raw gas outlet (F) in the heat recovery steam generator ( 3 ). For a more even discharge of the raw gas can be arranged more distributed on the circumference of the cooling chamber raw gas outlets. In the embodiment with only one raw gas outlet (F), the average distance of the raw gas through the cooling space is extended, whereby an increased separation of particles is achieved.

The Steam generator system is called a forced pass system with a rising Train, a Querzug and a falling train designed. At the bottom End of the rising train and the falling train is ever a water bath E2, E3 arranged. The rising train, the transverse train, the falling Zug and the two water baths E2, E3 like too be integrated into a pressure-resistant unit. The raw gas from the Off-gas exhaust F of the air flow gasifier is the rising train between Water bath E2 and radiation evaporator (I) supplied. To entering the steam generator system passes the hot Crude gas after each other, designed as a cooling screen Radiation evaporator (I), the Scotch evaporator (J), the bulkhead superheater (2nd superheater stage) (K), the convective superheater located in the transverse train (1st superheater stage) (L) and then the snake tube preheater designed economizer (M). The radiation evaporator (I) and the Scotch evaporator (J), are arranged in the rising train. Of the Economizer (M) is arranged in the falling train.

In the radiation evaporator (I), the bulk steam evaporator (J), and the bulkhead superheater (K) is the clogged slag in the raw gas cooled down below its melting temperature.

at the configuration according to the invention is ensured that the convective heat exchanger only with raw gas comes in contact, whose entrained slag to below their melting temperature was cooled down. hereby are slagging of the transformer in an advantageous manner minimized. For cleaning the heat exchanger can Cleaning systems, such as knockers, steam blowers, be arranged.

In the rising train is entrained in the raw gas entrained particles by gravity separation in the water bath E2. In the falling Zug arrive entrained in the raw gas particles by gravity separation in the water bath E3.

If the rising train and the falling train are combined in one unit, they can be separated by a common separator T. Then at the lower end of the waste heat steam system ( 3 ) the two water baths E2, E3 separated by the separator T. The mass transport in the water baths E2, E3 of the waste heat steam system ( 3 ) is analogous to the refrigerator ( 2 ) by means of flow in the direction of Schlackeaustrags (H) amplified. The flow is maintained by circulating water between the slag discharge (H) and the slag water supply (G).

After the hot raw gas, the steam generator system ( 3 ) and cooled, it leaves this via the raw gas outlet (N), which is arranged between economizer (M) and water bath E3, and can be fed to the downstream stages.

The entrained flow gasifier and flanged heat recovery steam generator can be operated with a pressure of up to 8 MPa. LIST OF REFERENCE NUMBERS 1 gasification reactor 2 Refrigerator part quench 3 heat recovery steam generator 4 quench A Slag drain body B guide tube C quench nozzles D Quenchkörper E1, E2 E3 water bath F crude gas G Slag water supply H1, H slag discharge I radiation evaporator J Scots evaporator K Scotch superheater (2nd superheater stage) L Conv. Superheater (1st superheater stage) M economizer N Rohgasaustritt T separator

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• EP 0870818 A2 [0006]

Claims (10)

Device for quenching raw gas produced in an entrained-flow gasifier from the gasification of ash-containing feedstocks in the case of - under a gasification reactor ( 1 ) a cold room ( 2 ), - at the lower end of the cold room is a water bath, - the gasification reactor ( 1 ) via a crude gas and slag outlet (A) into a substantially tubular quench body (D) opens, which is arranged in the cooling space, - the quench body a quench chamber ( 4 ), whose cross-section in the flow direction of the raw gas does not shrink, are arranged in the quench body Quenchdüsen (C) for injecting quench water into the quench chamber, - a Rohgasabgang (F) is arranged in the pressure chamber delimiting the cooling jacket such that the lower edge of Rohgasabgangs above the lower edge of the Quenchkörpers (D) is positioned. Device according to claim 1, characterized in that that the lower edge of the quench body is below half Height between surface of the water bath as well Raw gas and slag waste (A) ends. Device according to one of the preceding claims, characterized in that a plurality of raw gas outlets (F) arranged distributed over the circumference of the refrigerator are. Device according to one of the preceding claims, characterized in that with the raw gas outlet (F) a heat recovery steam generator ( 3 ) is connected, which has a rising train, a Querzug and a falling train and in which - at the lower end of the rising train a water bath (E2) is arranged - at the lower end of the falling train a water bath (E3) is arranged, - in the rising train a radiation evaporator (I) is arranged, - the hot raw gas to the rising train between the water (E2) and radiation evaporator (I) can be supplied, - the radiation evaporator (I) is a steam evaporator (J) downstream in the flow direction of the raw gas, - the bulkhead (K) is followed by a convective superheater (L), - the convective superheater (L) is followed by a Schlangenrohrvorwärmer (M) and - the cooled raw gas via a Raw gas outlet (N) from the falling train between Schlangenrohrvorwärmer and water bath (E3) can be discharged. Device according to claim 4, characterized in that that the snake tube preheater through an economizer given is. Device according to one of the preceding claims 4 to 5, characterized in that the convective superheater is arranged in the transverse train. Device according to one of the preceding claims 4 to 6, characterized in that the steam generator system as Forced flow system is formed. Device according to one of the preceding claims 4 to 7, characterized in that the radiation evaporator as Cooling screen is formed. Device according to one of the preceding claims 4 to 8, characterized in that they with the rising train, the Querzug, the falling train, and the two water baths (E2, E3) forms a structural unit. Device according to one of the preceding claims 4 to 9, characterized in that for cleaning the heat exchanger Cleaning systems are arranged.