Method and membrane module for the energy-efficient oxygen generation during biomass gasification

Patent metadata

Field	Value
Publication number	US-2016040081-A1
Application number	US-201414782252-A
Country	US
Kind code	A1
Filing date	Apr 1, 2014
Priority date	Apr 5, 2013
Publication date	Feb 11, 2016
Grant date	—

Abstract

The invention relates to a method and a membrane module for process-integrated oxygen generation during biomass gasification, wherein the oxygen is generated at high temperature via mixed conducting ceramic membranes. It is the object of the invention to provide a possibility for energy-efficient oxygen generation in biomass gasification for increasing the efficiency of the overall process. According to the invention, the disadvantages of the prior art are remedied in that a membrane module is heated directly by the synthesis gas from the biomass gasification. However, this heating should only meet less than 20%, typically less than 10% and, under optimal conditions, only approximately 5% of the heat requirement of the membrane module. The predominant portion of the heat required to heat the fresh air is taken from the exhaust air of the membrane module through heat exchange.

First claim

1 .- 7 . (canceled)

8 . A method for energy-efficient oxygen generation in biomass gasification, wherein the method uses a membrane module with mixed conducting oxygen-permeable membranes for generating high purity oxygen, wherein gas exiting the membrane module is used to heat incoming fresh air, more than 50% of heat energy contained in the gas exiting the membrane module being utilized to preheat the fresh air, and wherein further heating of the fresh air to a temperature level of 800 to 900° C. is carried out by direct feeding of combustion gas or synthesis gas from the biomass gasification into a combustion space of the membrane module.

9 . The method of claim 8 , wherein a vacuum is generated inside the mixed conducting oxygen-permeable membranes by an electromechanical or mechanical vacuum pump or by a steam ejector.

10 . The method of claim 8 , wherein the combustion gas or synthesis gas from the biomass gasification is fed into a gas engine of a CHP plant, and a mechanical vacuum pump is mechanically coupled to the gas engine.

11 . The method of claim 9 , wherein the combustion gas or synthesis gas from the biomass gasification is fed into a gas engine of a CHP plant, and a mechanical vacuum pump is mechanically coupled to the gas engine.

12 . The method of claim 8 , wherein the fresh air entering the membrane module is heated with energy from the gas exiting from the membrane module via recuperators or regenerators.

13 . The method of claim 9 , wherein the fresh air entering the membrane module is heated with energy from the gas exiting from the membrane module via recuperators or regenerators.

14 . The method of claim 10 , wherein the fresh air entering the membrane module is heated with energy from the gas exiting from the membrane module via recuperators or regenerators.

15 . The method of claim 11 , wherein the fresh air entering the membrane module is heated with energy from the gas exiting from the membrane module via recuperators or regenerators.

16 . A membrane module with a housing and a mixed conducting membrane, wherein
the housing is provided in a lower region thereof with an inlet for combustion gas or synthesis gas and an outlet for exhaust gas with a connection plate and an insulation overlaying the latter, the mixed conducting membrane comprises a plurality of membrane tubes which are closed on one side and open on the other side, the open end of the membrane tubes being guided through the insulation to a joint gas discharge output located in the connection plate for extraction of at least obtained oxygen, at least one protective tube which is arranged over one, some, or all of the membrane tubes contacts at least the insulation on one side such that an intermediate space is formed between the membrane tubes and the protective tube and a combustion space is formed between the protective tube and the housing, fresh air being supplied to the intermediate space and combustion gas or synthesis gas being supplied to the combustion space, and the protective tube has an outlet orifice to the combustion space, which outlet orifice is opened such that a velocity of fresh air at the outlet orifice is greater than 0.2 m/s.

17 . The membrane module of claim 16 , wherein a tubular sweep lance is arranged inside each membrane tube for sweeping with water vapor.

18 . The membrane module of claim 16 , wherein the mixed conducting membrane is a BSCF membrane.

19 . The membrane module of claim 18 , wherein the mixed conducting membrane is a BSCF membrane.

Assignees

• Fraunhofer Ges Forschung

Inventors

• Kriegel Ralf

Classifications

• C10J2300/1884

  with one stream being synthesis gas · CPC title

• C10J2300/1678

  with air separation · CPC title

• Y02E20/14

  Combined heat and power generation [CHP] · CPC title

• C10J2300/0959

  Oxygen · CPC title

• B01D2319/04

  Elements in parallel · CPC title