NZ214174A

NZ214174A - Reactor for production of synthesis gas by partial combustion of solid fuel

Info

Publication number: NZ214174A
Application number: NZ214174A
Authority: NZ
Inventors: Der Burgt M J Van; W J A H Schoeber; P J Jones; H W Luke
Original assignee: Shell Int Research
Priority date: 1984-11-15
Filing date: 1985-11-13
Publication date: 1988-04-29
Also published as: AU4984685A; ZA858696B; CN85108252A; NL8403493A; DE3540304A1; CN1004269B; AU570581B2; JPS61122101A

Description

214174 Priority Date(s): Complete Specification Fifed: Class: ...C.(°-UZ/PO . .. , 2 9 APR 1988 Publication Date: P.O. Journal, No: /3Q7.

NEW ZEALAND PATENTS ACT, 1953 No.: Date: COMPLETE SPECIFICATION REACTOR AND PROCESS FOR PRODUCING A SYNTHESIS GAS 1*W«, SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ B.V., Carel van Bylandtlaan 30 - 2-596 HR The Hague, the Netherlands, a Netherlands Company hereby declare the invention for which we pray that a patent may be granted to ftltf/us, and the method by which it is to be performed, to be particularly described in and by the following statement: - - 1 - (followed by page la) 2 141 - lac- K 9419 nTTY-nrm atto mrrr" rnv rrmnrTTTo n TVTTTmnn rfin The invention relates to a reactor and a process for producing a synthesis gas by partial combustion of a carbon-containing fuel.

Such reactors and processes are kncwn and examples of caibon-containing fuels enployed in them are hard coal, brcwn coal, peat, petroleum or products thereof. The partial canbustion takes place with the aid of oxygen or an oxygen-containing gas, such as air. The synthesis gas produced in this way ccnprises substantially carbon monoxide and hydrogen and may contain lesser amounts of carbon dioxide, methane and water vapour.

The above-mentioned fuels contain all sorts of inorganic substances which, after carbustion, remain behind as ash particles. Seme of the ash particles will be entrained by the synthesis gas formed during the reaction. Since the temperature of the synthesis gas in the reactor is very high, the fine ash particles will be wholly or partly liquid and therefore sticky. These sticky liquid or semi-liquid ash particles tend to deposit on parts of the reactor, in particular on the inner surface of the wall of the reactor space, which can ultimately lead to blockage of the reactor.

The object of the invention is to solve this problem by providing a reactor of the above-mentioned type, which reactor according to the invention is characterized in that means are present for the creation and maintenance of a water layer along at least part of the inner surface of the wall of the reactor space.

An advantageous enbodiment of the reactor according to the invention is characterized in that the means ccrrprise a water distribution device located in the upper part of the reactor space.

The said water distribution device can be constructed as an overflew located near the inner surface of the wall of the reactor space.

It is also possible to construct the said water distribution device as a spray device.

The reactor according to the invention will now be described with reference to the drawings in which: Figure 1 shews schematically a vertical sectional view of a reactor provided with a water distribution device constructed as an overflew.

Figure 2 shews a sectional view taken along the plane II-II shewn in Figure 1.

Figure 3 shews schematically a vertical sectional view of a part of a reactor in which is located a water distribution device constructed as a spray device comprising a circular tube provided with a slit.

Figure 4 shews schematically a vertical sectional view of a part of a reactor in which is located a water distribution device constructed as a spray device comprising a circular tube provided with a wall consisting of a porous material.

In Figures 1 and 2 the reference numeral 1 indicates the reactor space, which is bounded by a side wall 2, a top wall 3 and a bottom wall 4. The top of the reactor is provided with an outlet 5 for discharging the produced synthesis gas from the reactor space 1. The bottom of the reactor is also provided with an outlet indicated by reference numeral 6, through which water and ash particles can fee removed from the reactor space 1.

The reactor is provided with four burners 7, each one of which is provided with supply lines 8 and 9 for the supply of fuel and oxygen or an oxygen-containing gas respectively. In the upper part of the reactor space 1 is located a water distribution device, which in this case is constructed as a trough 10 mounted in the wall 2, the upper edge 13 of a vertical wall 11 functioning as overflew. The trough 10 is provided with a supply line 12, through which water can be fed to the trough 10. 7 14174 The arrcws a, b and c in Figures 1 and 2 indicate the flew of the water being supplied via water distribution device 10, 11, 13 to the reactor.

In Figures 3 and 4 the same parts are indicated by the sane reference numerals as in Figures 1 and 2.

In Figure 3 the water distribution device is constructed as a spray device having the form of a circular tube 15 located in the wall 2. The circular tube 15 is provided with a water passage, which in this case has the form of a slit 16. Instead of a slit 16, the circular tube 15 may, if desired, be provided with a series of orifices (not shewn). The circular tube 15 is provided with a supply line 17, through which water can be fed to the circular tube 15.

In Figure 3 the arrcws d and e indicate the flew of the water fed via the circular tube 15 to the reactor.

In Figure 4 the water distribution device is constructed as a spray device which has the form of a circular tube 2 and is located in the wall 2. The circular tube 20 is provided with a water passage, which in this case is formed by a part of the wall of the circular tube 20, which consists of a porous material. This part of the wall is indicated by the reference numeral 21. The circular tube 20 is provided with a supply line 22, through which water can be fed to the circular tube 20.

In Figure 4 the arrews f and g indicate the flew of the water fed via the circular tube 20 to the reactor.

The operation of the reactor according to the invention will new be described with reference to the drawings.

A carbon-containing fuel, for example pulverized coal, is fed via the pipes 8 to the burners 7. At the same time, oxygen or another oxygen-containing gas is fed via the pipes 9 to the burners 7. If desired, steam can also be fed to the burners. By means of the burners 7, the desired partial ccrtfcustion is brought about in the reactor space 1. The synthesis gas formed is discharged fran the reactor space 1 through the outlet 5.

Water is fed via the pipe 12 to the trough 10. The water flews 14174 over the top edge 13 of the vertical wall 11 into the reactor space 1. The water flews over the top edge 13 of the vertical wall 11 into the reactor space 1 as shewn by the arrcws a. The water then flows along the inner surface 14 of the wall 2 in the way illustrated by the arrows b. Finally, the water flews along the inner surface 18 of the bottcm wall 4 according to the arrcws c to the outlet 6. In this way the water forms a water layer or water film along the inner surfaces 14 and 18 of the walls 2 and 4 £7\ respectively of the reactor space 1. The water layer catches liquid ^ or semi-liquid ash particles, causing these particles to solidify and lose their stickiness. These solid ash particles are then entrained with the water to the outlet 6 and thereby removed, from "■y •j the reactor space. This prevents the sticky ash particles from 3 depositing on the inner surfaces of the walls 2 and 4, thereby ^ protecting these walls and preventing blockage of the reactor space j 1. The water also ensures an effective cooling of the walls 2 and i 4. On account of the high temperatures prevailing in the reactor space 1, part of the water fed to the reactor space 1 will be converted into steam. This steam will, at least partly, participate in the reaction in the reactor space 1. If the heat generation in the reactor space 1 increases, more steam will be formed frcm the added water. This additional quantity of steam thus formed will function as a moderator, so that the temperature in the reactor space 1 will tend to fall somewhat.

The water discharged via the outlet 6 may be recirculated after removal of the ash particles from the water. In the embodiment shewn in Figures 1 and 2, the wall 2 of the reactor makes a small angle with a vertical plane (for exanple 3°), which has the advantage of ensuring that the water layer will not detach frcm the inner surface 14 of the wall 2.

If the water distribution device as shown in Figure 3 is used, water is fed via the pipe 17 to the circular tube 15. This water then flows via the slit 16 to the inner surface 14 of the wall 2, as shewn by the arrcws d. Subsequently, the water flews according to the arrcws e along the inner surface 14 of the wall 2 of the 1 14 1 reactor space 1 in a dcwnward direction in the same way as described with reference to Figures 1 and 2.

If the water distribution device as shown in Figure 4 is used, water is fed via the pipe 22 to the circular tube 20. This water then flews via the porous wall 21 to the inner surface 14 of the wall 2, as shown by the arrows f. Subsequently, the water flows according to the arrows g along the inner surface 14 of the wall 2 of the reactor space 1 in a dcwnward direction in the same way as described with reference to Figures 1 and 2.

Just a few of the possible embodiments of the water distribution device according to the invention have been described here by way of example. Mary other embodiments of the water distribution device are, however, also possible. The main thing is for the device to be constructed such as to create and maintain a water layer extending along at least part of the inner surface of the wall of the reactor space.

The reactor described above is provided at its top with an outlet for discharging frcm the reactor space the synthesis gas produced. Reactors are, however, also known of the type that is provided at the bottcm with an outlet for the synthesis gas produced. For these last mentioned reactors as well, the means according to the invention can advantageously be employed for creating and maintaining a water layer along at least part of the inner surface of the wall of the reactor space.

It is not necessary for the water layer to extend along the vrtiole inner surface of the wall of the reactor space. It is, for example, possible for the water layer to extend just along the inner surface of the wall of the reactor space situated below the level of the burners. In that case, the means for creating and naintaining the water layer will also be located below the level of the burners. 214174

Claims

WHAT WE CLAIM IS:

1. A reactor for the production of a synthesis gas by partial carbustion of a carbon-containing fuel, characterized in that means are present for creating and maintaining a water layer along at least part of the inner surface of the wall of the reactor space.

2. The reactor as claimed in claim 1, characterized in that the said means comprise a water distribution device located in the top part of the reactor space.

3. The reactor as claimed in claim 2, characterized in that the water distribution device is constructed as an overflow located near the inner surface of the wall of the reactor space.

4. The reactor as claimed in claim 2, characterized in that the water distribution device is constructed as a spray device.

5. The reactor as claimed in claim 4, characterized in that the water distribution device is a circular tube located near the inner surface of the wall of the reactor space, which circular tube is provided with a water passage.

6. The reactor as claimed in claim 5, characterized in that the water passage consists of a slit or a series of orifices in the circular tube.

7. The reactor as claimed in claim 5, characterized in that the water passage if formed by at least part of the wall of the circular tube comprising a porous material.

8. The reactor as claimed in any one of claims 1-7, characterized in that the wall of the reactor space makes an angle of 3° wi th,*«vfc M ,'/ v~ i vertical plane. •v/R

9. A process for producing synthesis gas by partial ccrnbustipn of a carbon-containing fuel, characterized in that a reactor is % ' HW employed according to one or more of claims 1-7. f? CQRH04 DATED TK- | C^DAY 0 a I PAR K Qjr K & SON