CN88102581A

CN88102581A - The method and apparatus of preparation synthetic gas

Info

Publication number: CN88102581A
Application number: CN88102581.XA
Authority: CN
Inventors: 冈特·克劳斯·埃克斯坦
Original assignee: Shell Internationale Research Maatschappij BV
Current assignee: Shell Internationale Research Maatschappij BV
Priority date: 1987-05-05
Filing date: 1988-05-03
Publication date: 1988-11-16
Also published as: EP0290087A2; CN1018187B; CA1336645C; ZA883134B; DE3714915A1; EP0290087B1; AU599786B2; AU1552588A; JPS63286493A; EP0290087A3; JP2609533B2; DE3860637D1

Abstract

在反应器中用含氧气体部分燃烧细粉碎的固体含碳燃料生产合成气的方法。部分燃烧过程中所形成的液态残渣落入水槽或残渣急冷器固化，然后靠重力落入闭锁漏斗，从漏斗中分批将固化了的残渣排出气化系统。闭锁漏斗中形成并维持气泡或气帽，气泡的压力低于残渣急冷器的压力，因此在打开漏斗与残渣急冷器之间的阀门时，可产生水和残渣的初始向下流动。Process for the production of synthesis gas by partial combustion of finely divided solid carbonaceous fuels with an oxygen-containing gas in a reactor. The liquid residue formed in the partial combustion process falls into the water tank or the residue quencher to solidify, and then falls into the locking funnel by gravity, and the solidified residue is discharged from the gasification system in batches from the funnel. A bubble or gas cap is formed and maintained in the lock funnel, the pressure of the bubble is lower than that of the slag quencher, so that when the valve between the hopper and the slag quencher is opened, an initial downward flow of water and slag is created.

Description

Process and apparatus for producing synthesis gas

The present invention relates to a process for the partial combustion of finely divided solid carbonaceous fuel with an oxygen-containing gas in a reactor to produce synthesis gas. The liquid residue formed in the process of partial combustion is discharged from an outlet at the bottom of the reactor and enters a water tank or a residue quencher for quenching solidification through a residue discharge device by gravity.

Partial combustion of finely divided solid carbonaceous fuel with substantially pure oxygen as the oxygen-containing gas produces a synthesis gas consisting essentially of carbon monoxide and hydrogen. When the oxygen-containing gas used is air or oxygen-enriched air, the resulting synthesis gas will contain a significant amount of nitrogen. As used herein, "solid carbonaceous fuel" generally refers to coal or other solid fuels, such as lignite, peat, wood, coke, coal ash, and the like. However, mixtures of liquid or gaseous and solid particulate fuels are also useful.

It is advantageous to introduce a regulator into the reactor, the function of which is to regulate the temperature of the reactor. This is achieved by an endothermic reaction between the modifier and the reactants and/or products produced. Suitable regulators are steam and carbon dioxide.

The gasification reaction is advantageously carried out at a temperature of 1200 ℃ and 1700 ℃ and at a pressure of 1 to 200 bar.

The reactor used for the preparation of the synthesis gas may have any suitable shape.

The finely divided solid carbonaceous fuel and oxygen-containing gas may be fed to the reactor in any suitable manner as is appropriate for the purpose. And need not be described in detail herein.

The liquid residue formed by the partial combustion reaction falls and is discharged from an outlet at the bottom of the reactor.

To remove the residue from the gasification process, it is known to provide a quench water tank or residue quencher below the reactor, which quench is connected to the reactor by any suitable means, and which traps the gravitationally moving residue, which cools it to form sintered pellets or agglomerates. After the clinker has formed, it is discharged periodically or continuously using conventional equipment.

For example, a lock hopper may be used to achieve this, with the solidified residue being discharged from the gasification system in batches.

During periods of outward discharge of the slag, one or more valves on the connection between the slag chiller and the hopper are closed to isolate the hopper from the gasification system.

However, the residue from the partial combustion process is now collected in the quench cooler above the valves, and the residue tends to bridge up the narrow space above the valves. After the funnel and the gasification system are reconnected, it is difficult to allow the residue to fall back into the funnel. Even stirring with a water jet nozzle is not successful.

It is therefore an object of the present invention to provide a method and apparatus for the partial combustion of finely divided solid carbonaceous fuel to produce synthesis gas in which the liquid residue formed during the partial combustion can be discharged from the residue chiller in an efficient manner with great ease and efficiency.

It is another object of the present invention to provide a rapid performance test of the valve between the residue chiller and the lockhopper.

To this end, the invention provides a process for the production of synthesis gas by partial combustion of finely divided solid carbonaceous fuel with an oxygen-containing gas in a reactor, wherein the residue formed during the partial combustion falls into a water bath or a quench cooler for solidification and then falls by gravity into a lock hopper from which the solidified residue is discharged from the gasification system in batches, said lock hopper and residue quench cooler being connected by one or more valves, the process comprising the step of forming and maintaining a permanent gas bubble or gas cap in the lock hopper, the pressure of said gas bubble being lower than the pressure in the residue quench cooler, whereby on opening the valve between the lock hopper and the residue quench cooler an initial flow of water and residue downwards is formed.

The present invention also provides an apparatus for carrying out the above method comprising a residue chiller connected to a lock hopper through one or more valves, the bottom of the hopper being provided with an outlet consisting of one or more external valves, and means for forming and maintaining a permanent bubble or gas cap in the lock hopper.

In an advantageous embodiment of the invention, the air bubbles in the locking funnel can be formed by inserting a length of tubing down the upper part of the funnel.

In another advantageous embodiment of the invention, the gas bubbles consist of an inert gas (e.g. nitrogen).

The invention will now be described in more detail by way of example with reference to the accompanying drawings, in which fig. 1 and 2 each schematically show an advantageous embodiment of the device according to the invention.

Referring to FIGS. 1 and 2, a cross section of a residue chiller 1 with an outlet 2 is shown. The residual chiller 1 is part of a gasification system that is positioned below the reactor or gasification section in which the partial combustion process is conducted and can be connected in any manner suitable for the purpose.

The gassing section is not shown for clarity. The outlet 2 of the residue chiller 1 is connected via a suitable connecting line 3 to a lock hopper 4 arranged therebelow. One or more valves 3a are provided in the line 3.

In the lock hopper 4, a permanent bubble or gas cap 5 is maintained at a pressure lower than that of the residue chiller 1. The bubbles may be composed of an inert gas such as nitrogen.

The bottom of the lockhopper 4 is provided with an outlet 7 and one or more valves 7a for discharging solidified residue from the gasification system during a discharge cycle. The discharged residue may be received by any suitable means (not shown for clarity). The gas bubbles 5 in the hopper may be maintained by supplying an inert gas (e.g., nitrogen) to the lockhopper 4 via a tube 6 (shown in fig. 1) extending into the headspace of the lockhopper 4, or more advantageously, via a tube 6a (shown in fig. 2) in fluid communication with the vertical tube between the residue chiller 1 and the hopper 4, which extends into the interior of the hopper for a length sufficient to maintain the uppermost bubbles in the hopper.

The operation of the system of the present invention is as follows:

the liquid residue formed during the partial combustion of the gasification system falls into a water tank or chiller 1 where it solidifies. And then dropped by the quencher 1 into the lock hopper 4 by gravity. The solidified residue is discharged from the gasification system in batches via a funnel 4. It will be apparent to those skilled in the art that valves 3a and 7a should be opened and closed, respectively, at appropriate times.

During the discharge period, valve 3a between the quencher and the hopper is closed, isolating hopper 4 from the gasification system, at which time valve 7a at outlet 7 is opened. The now formed residue collects in the residue chiller above the valves 3a and tends to build up in the narrower part above these valves (shown as region a).

According to the present invention, after the lock hopper 4 is connected to the gasification system by closing the valve 7a and opening the valve 3a, bubbles having a pressure lower than the pressure in the residue chiller cause an initial downward flow of water and residue, breaking down the residue held up in zone a.

Notably, the air bubbles also allow for rapid performance verification of the valve. If the volume of the bubble changes with time, the valve is proved to have a leakage phenomenon.

It should also be noted that the pressure of the air bubbles in the lock hopper may be higher than the pressure of the discharge device outside the hopper. This makes the discharge of the hopper easier and reduces the volume at the outlet 7.

Various modifications to the present invention will be readily apparent to those skilled in the art from the foregoing description and accompanying drawings. Such modifications are intended to fall within the scope of the appended claims.

Claims

1. A method for the production of synthesis gas by partial combustion of finely divided carbonaceous fuel with an oxygen-containing gas in a reactor, wherein liquid residue formed during the partial combustion falls into a water bath or quench cooler for solidification and then falls by gravity into a lock hopper from which the solidified residue is discharged from the gasification system in batches, said hopper and quench cooler being connected by one or more valves, the method comprising the step of forming and maintaining a permanent gas bubble or gas cap in the lock hopper, the pressure of said gas bubble being lower than the pressure in the residue quench cooler, whereby an initial flow of water and residue downwards is formed upon opening the valve between the lock hopper and the residue quench cooler.

2. The method of claim 1, wherein the bubble is maintained by supplying gas to the funnel through a conduit extending into the upper space of the lock-out funnel.

3. A method according to claim 1 or 2, wherein the bubbles are formed of an inert gas.

4. The method of claim 3 wherein said inert gas is nitrogen.

5. A method substantially as described with reference to the accompanying drawings.

6. An apparatus for carrying out the method of any one of claims 1 to 5 comprising a residue chiller connected to a lock hopper via one or more valves, the bottom of the hopper being provided with an outlet formed by one or more valves, and means for forming and maintaining permanent gas bubbles in the lock hopper.

7. The apparatus of claim 6, including a conduit extending into the upper space of the lock hopper.

8. Apparatus substantially as hereinbefore described with reference to the accompanying drawings.