Synthesis gas generation complex and process

• US 4,799,356 A
• Filed: 07/28/1986
• Issued: 01/24/1989
• Est. Priority Date: 07/28/1986
• Status: Expired due to Term

• Current Assignee: Shell Oil Company (Shell Plc)
• Original Assignee: Shell Oil Company (Shell Plc)
• Inventors: Doering, Egon L.
• Primary Examiner(s): Husar, Stephen F.
• Application Number:
  US06/890,035
• Time in Patent Office: 911 Days
• Field of Search: 60/648, 60/653, 60/670, 60/677, 110/229, 122/5, 48/197 R, 48/210
• US Class Current: 60/648
• CPC Class Codes: F01K 21/00 Steam engine plants not otherwise provided for
• CPC Class Codes: Y02E 20/34 Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery

Abstract

A synthesis gas-power generation complex is disclosed, the complex being characterized by ability to generate sufficient electrical power for internal use and for export, and by structure for improved heat recovery and utilization. A process for synthesis gas production and power generation utilizing these concepts is also disclosed.

Claims

1. A synthesis gas generation complex comprising

(a) a coal gasification plant, including at least one gasifier for the gasification of coal to produce synthesis gas at a temperature of about 2000°

F. to 3000°

F., the gasifier having heat exchange surfaces adapted for indirect heat exchange with steam and water;

(b) a heat exchange section comprising at least one heat exchanger in gas flow communication with said gasifier, said heat exchanger comprising at least one segment adapted to generate superheated steam, and lower temperature heat exchange segments;

(c) a gas cleanup section in flor communication with said heat exchanger, said cleanup section comprising means for removing particulates and H₂ S from said synthesis gas;

(d) a steam turbine adapted to receive and utilize superheated steam and produce a low temperature vapor, said steam turbine driving an electrical generator;

(e) means for providing superheated steam from said heat exchanger to said steam turbine;

(f) means for condensing low temperature vapor froms aid steam turbine to produce condensate, in flow communication with said steam turbine; and

(g) means for supplying condensate, from said means for condensing low temperature vapor, to a lower temperature heat exchange segment of at least one heat exchanger in said heat exchange section for indirect heat exchange of said condensate;

(h) means for recovering heated condensate from said lower temperature heat exchange section; and

(i) means for supplying heated condensate from said means for recovering heated condensate to the heat exchange surfaces of a gasifer in said gasification zone for indirect heat exchange generation of steam.

2. The complex of claim 1 wherein the gasifier comprises at least one burner adapted to utilize dry particulate coal.

3. A process for the production of synthesis gas and power generation comprising

(a) partically oxidizing coal at an elevated temperature by feeding dry particulate coal and oxygen to a gasification zone, the ratio of coal to oxygen being such as to maintain a reducing atmosphere, and producing raw synthesis gas having a temperature of from about 2000°

F. to about 3000°

F. and removing heat from said synthesis gas in said gasification zone by indirect heat exchange with steam and water at a temperature of about 220°

F. to 650°

F.;

(b) passing raw synthesis gas from step (a) to a heat exchange zone comprising a superheated steam generating system section and a lower temperature heat exchange section, and removing heat from said synthesis gas by indirect heat exchange with steam, and water at a temperature of from about 220°

F. to about 650°

F., and producing superheated steam from said steam;

(c) removing particulates and H₂ S from said raw synthesis gas, producing a purified synthesis gas;

(d) passing superheated steam from said heat exchange zone to at least one steam turbine, and expanding superheated steam from said heat exchange zone through said steam turbine, producing a low temperature water vapor and driving said turbine, said steam turbine driving an electrical generator and producing electric power;

(e) condensing said low temperature water vapor, and passing condensate to the lower temperature heat exchange section, and utilizing said condensate as the water in step (b), producing heated condensate; and

(f) utilizing heated condensate produced by heat exchange in step (e) as the water for indirect heat exchange in step (a).

4. The process of claim 3 wherein the gasification zone comprises at least one burner for oxidizing the coal.

5. A synthesis gas generation complex comprising

(a) a coal gasification plant, including at least one gasifier for the gasification of coal to produce synthesis gas at a temperature of about 2000°

F. to 3000°

F., the gasifier having heat exchange surfaces adapted for indirect heat exchange with steam and water;

(b) a heat exchange section comprising at least one heat exchanger in gas flow communication with said gasifier, said heat exchanger comprising at least one segment adapted to generate superheated steam, and lower temperature heat exchange segments;

(c) a gas cleanup section in flow communication with said heat exchanger, said cleanup section comprising means for removing particulates and H₂ S from said synthesis gas;

(d) a steam turbine adapted to receive and utilize superheated steam and produce a low temperature vapor, said steam turbine driving an electrical generator;

(e) means for providing superheated steam from said heat exchanger to said steam turbine;

(f) means for condensing low temperature vapor from said steam turbine to produce condensate, in flow communication with said steam turbine;

(g) means for supplying condensate, from said means for condensing low temperature vapor, to a lower temperature heat exchange segment of at least one heat exchanger in said heat exchange section for indirect heat exchange of said condensate;

(h) means for recovering heated condensate from said lower temperature heat exchange section;

(i) means for supplying heated condensate from said means for recovering heated condensate to the heat exchange surface of a gasifier in said gasification zone for indirect heat exchange generation of steam; and

(j) means for passing intermediate steam from the steam turbine to said cleanup section.

6. A process for the production of synthesis gas and power generation comprising

(a) partially oxidizing coal at an elevated temperature by feeding dry particulate coal and oxygen to a gasification zone, the ratio of coal to oxygen being such as to maintain a reducing atmosphere, and producing raw synthesis gas having a temperature of from about 2000°

F. to about 3000°

F. and removing heat from said synthesis gas in said gasification zone by indirect heat exchange with steam and water at a temperature of about 220°

F. to 650°

F.;

(b) passing raw synthesis gas from step a) to a heat exchange zone comprising a superheated steam generating system section and a lower temperature heat exchange section, and removing heat from said synthesis gas by indirect heat exchange with steam, and water at a temperature of from about 220°

F. to about 650°

F., and producing superheated steam from said steam;

(c) removing particulates and H₂ S from said raw synthesis gas, producing a purified synthesis gas;

(d) passing superheated steam from said heat exchange zone to at least one steam turbine, and expanding superheated steam from said heat exchange zone through said steam turbine, producing a low temperature water vapor and driving said turbine, said steam turbine driving an electrical generator and producing electric power;

(e) condensing said low temperature water vapor, and passing condensate to the lower temperature heat exchange section, and utilizing said condensate as the water in step (b), producing heated condensate;

(f) utilizing heated condensate produced by heat exchange in step (e) as the water for indirect heat exchange in step (a); and

(g) passing intermediate steam produced in the steam turbine to the cleanup section and utilizing passed intermediate steam for heat exchange therein.