Dust separation from the crude gas of an entrained flow gasifier

Patent metadata

Field	Value
Publication number	US-9434896-B2
Application number	US-201414449508-A
Country	US
Kind code	B2
Filing date	Aug 1, 2014
Priority date	Aug 1, 2013
Publication date	Sep 6, 2016
Grant date	Sep 6, 2016

Abstract

A multistage gas washing system is applied for dust separation from crude gases of entrained flow gasification of pulverized fuels under pressures up to 10 MPa and temperatures which are greater than the melting point of the fuel ash. A first stage comprises a modified quenching system and a downstream washing column, which operates as a bubble column. A second washing stage comprises one or more Venturi washers connected in series. A third washing stage comprises multiple high-pressure atomization units of washing water, a partial condenser for cooling the crude gas by 1 to 15° C. with condensate formation, and a separation column, which is equipped with washing surfaces and a plastic-coated demister.

First claim

What is claimed:

1. A multistage crude gas washing apparatus for an entrained flow gasification plant comprising:
an entrained gas flow gasification chamber configured to operate at pressures up to 10 MPa and temperatures up to 1900° C. to produce a crude gas;
a first crude gas washing stage having a quenching chamber connected downstream of the gasification chamber and configured to coarsely purify the crude gas generated in the gasification chamber, the first stage including injecting devices configured to inject water into the crude gas, cool the crude gas to a temperature between 150 and 250° C., and saturate the crude gas with water vapor;
a washing column located downstream of the quenching chamber, the washing column having a bottom part having a water bath, the washing column configured to cause the crude gas to flow through the water bath as a bubble column;
a second crude gas washing stage located downstream of the washing column, the second crude gas washing stage including at least one Venturi washer for the crude gas and a washing water separator located downstream of the at least one Venturi washer and configured to separate washing water from the crude gas flow;
a third crude gas washing stage located downstream of the water separator, the third crude gas washing stage having a high-pressure injection nozzle configured to inject finely-dispersed washing water that is free of solid material into the crude gas; and
a demister located within the third crude gas washing stage.

2. The crude gas washing system as claimed in claim 1 , wherein the demister comprises a droplet separator.

3. The crude gas washing system as claimed in claim 2 , further comprising a separation column following the droplet separator in the path of the washed crude gas, the separation column having a plate column and a demister which are both arranged after the droplet separator.

4. The crude gas washing system as claimed in claim 3 , wherein the droplet separator includes washing surfaces therein.

5. The crude gas washing system as claimed in claim 1 , further comprising:
a partial condenser after the high-pressure injection nozzle in the path of the crude gas,
a further high-pressure injection nozzle following the condenser in the path of the crude gas and configured for finely-dispersed injection of solids-free washing water into the crude gas; and
a separation column following the further high-pressure injection nozzle in the path of the crude gas, the separation column having a plate column therein; and, a separate demister in the plate column.

6. The crude gas washing system as claimed in claim 1 , wherein the high-pressure injection nozzle of the third crude gas washing stage is supplied with water and is configured to inject water in quantities and temperatures selected such that the crude gas experiences a cooling of 1 to 15° C.

7. The crude gas washing system as claimed in claim 6 , further comprising a
discharge for crude gas from the quencher;
a hood positioned and configured for covering the crude gas discharge from the quencher;
and water spraying nozzles in the quencher under the hood.

8. The crude gas washing system as claimed in claim 7 , further comprising a partition wall protruding from below into a volume in the quencher enclosed by the hood.

9. The crude gas washing system as claimed in claim 7 , wherein the hood extends around an entire circumference of the quencher.

10. The crude gas washing system as claimed in claim 1 , wherein the at least one Venturi washer includes a throat which is variable.

11. The crude gas washing system as claimed in claim 1 , further comprising
a further injection nozzle configured for receiving and injecting washing water such that the washing water is injected into the path of the crude gas between the crude gas discharge from the quencher and the washing column.

12. The crude gas washing system as claimed in claim 1 , wherein the system is configured to separate carbon black from the entrained flow and into water, and configured so that discharge condensate from the crude gas and the carbon black water are supplied again to the washing stages after processing in the system.

13. The crude gas washing system as claimed in claim 1 , wherein the demister is coated with PTFE.

14. The crude gas washing system as claimed in claim 1 , wherein the demister is coated with a Teflon compound.

Assignees

• Siemens Ag

Inventors

• Hannemann Frank
• Schingnitz Manfred

Classifications

• C10J2300/093

  Coal · CPC title

• C10J3/485

  Entrained flow gasifiers · CPC title

• C10K1/101

  with water only · CPC title

• C10J3/84 Primary

  with means for removing dust or tar from the gas · CPC title