Fuel slurry heating system and method

Patent metadata

Field	Value
Publication number	US-9447337-B2
Application number	US-201113522312-A
Country	US
Kind code	B2
Filing date	Aug 19, 2011
Priority date	Aug 19, 2011
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

The disclosed embodiments relate to systems and methods for heating a slurry to increase a solids concentration of the slurry while maintaining the viscosity of the slurry below a threshold viscosity. For example, in one embodiment, a system includes a fuel slurry preparation system having a slurry tank configured to hold a fuel slurry, the fuel slurry having a solid fuel and a liquid. The fuel slurry preparation system also includes a heat source and a controller configured to control the heat source to heat the fuel slurry to decrease a viscosity of the slurry below a threshold viscosity.

First claim

The invention claimed is:

1. A system, comprising:
a fuel slurry preparation system, comprising:
a grinding mill configured to receive a solid fuel and a liquid, to reduce a particle size of the solid fuel, and to mix the solid fuel with the liquid to form a first fuel slurry having a first solids concentration;
a closed vessel disposed downstream from and fluidly coupled to the grinding mill, wherein the closed vessel is configured to receive the first fuel slurry from the grinding mill and to hold the first fuel slurry;
a heat source coupled to the closed vessel and to a steam source in a gasification plant, the heat source being configured to receive steam generated in the gasification plant, wherein the heat source is configured to heat the first fuel slurry;
a fuel supply unit disposed downstream from the grinding mill, the closed vessel, and the heat source, wherein the fuel supply unit is configured to provide an additional amount of solid fuel to the first fuel slurry downstream of the closed vessel to adjust a solids concentration of the first fuel slurry and generate a second fuel slurry having a second solids concentration that is greater than the first solids concentration;

a control system configured to control the heat source to heat the first fuel slurry while the first fuel slurry is in the closed vessel to decrease a viscosity of the first fuel slurry below a threshold viscosity, within the closed vessel and the control system is configured to control the additional amount of solid fuel provided to the first fuel slurry by the fuel supply unit in response to a monitored viscosity or solids concentration of the first fuel slurry; and
a gasifier fluidly coupled to the closed vessel, wherein the gasifier is configured to receive the second fuel slurry and gasify the second fuel slurry to produce syngas.

2. The system of claim 1 , wherein the heat source is disposed along an output flow path external to the vessel.

3. The system of claim 1 , wherein the heat source comprises a steam sparging applicator configured to output a flow of steam into the vessel to directly contact the first fuel slurry in the vessel.

4. The system of claim 1 , wherein the heat source comprises a heat exchanger disposed in the vessel.

5. The system of claim 1 , wherein the heat source comprises a heating jacket configured to at least partially surround the vessel.

6. The system of claim 1 , comprising a slurry pump configured to receive the first fuel slurry from the vessel, and the threshold viscosity is at a transition between a pumpable viscosity and an unpumpable viscosity of the first fuel slurry by the slurry pump.

7. The system of claim 1 , wherein the control system is configured to control the heat source to adjust heat transfer to the first fuel slurry to adjust a solids concentration and a viscosity of the first fuel slurry between upper and lower thresholds.

8. The system of claim 7 , comprising a liquid removal unit disposed downstream from the closed vessel and configured to remove an amount of liquid from the first fuel slurry to adjust at least one of a viscosity or a solids concentration of the first fuel slurry, wherein the control system is configured to control the amount of liquid removed from the first fuel slurry by the liquid removal unit.

9. The system of claim 8 , wherein the control system is configured to monitor the viscosity or a solids concentration of the first fuel slurry, and to adjust the heat source, the liquid removal unit, or a combination, in response to a change in at least one of the viscosity or the solids concentration.

10. A system, comprising:
a grinding mill configured to receive a first solid fuel and a liquid, to reduce a particle size of the first solid fuel, and to mix the first solid fuel with the liquid to form a first fuel slurry;
a fuel slurry preparation vessel configured to receive the first fuel slurry from the grinding mill and prepare the first fuel slurry, wherein the first fuel slurry has a viscosity above an upper viscosity threshold;
a control system configured to monitor one or more parameters of the first fuel slurry, wherein the one or more parameters comprise a viscosity of the first fuel slurry and a solids concentration of the first fuel slurry;
a fuel supply unit disposed downstream from the grinding mill and between the fuel slurry preparation vessel and a gasifier, wherein the fuel supply unit is configured to provide a second solid fuel to the first fuel slurry downstream of the fuel slurry preparation vessel to adjust the solids concentration of the first fuel slurry and generate a second fuel slurry; and
wherein the control system is configured to control the second solid fuel provided to the first fuel slurry by the fuel supply unit in response to a monitored viscosity or solids concentration of the first fuel slurry upstream of the fuel supply unit and to adjust heat transfer to the first fuel slurry to reduce the viscosity below the upper viscosity threshold, and wherein the upper viscosity threshold is at a transition between a pumpable viscosity and an unpumpable viscosity of the first fuel slurry by a slurry pump configured to pump the first fuel slurry toward the gasifier.

11. The system of claim 10 , wherein the control system is configured to adjust the heat transfer to adjust the viscosity between the upper viscosity threshold and a lower viscosity threshold.

12. The system of claim 10 , where in the control system is configured to adjust the heat transfer to adjust the solids concentration between a lower concentration threshold and an upper concentration threshold.

13. The system of claim 10 , wherein the control system is configured to monitor the viscosity and the solids concentration of the first fuel slurry, and the control system is configured to adjust heat transfer to the first fuel slurry by the heat source in response to a change in the viscosity or the solids concentration.

14. The system of claim 10 , wherein the system comprises the heat source, the heat source comprises a steam flow path, and the control system is configured to control a steam flow through the steam flow path to control the heat transfer to the first fuel slurry.

15. The system of claim 10 , wherein the gasifier is configured to receive the second fuel slurry at the viscosity below the upper viscosity threshold and the solids concentration above the lower concentration threshold.

Assignees

• Steele Raymond Douglas
• Kanniappan Sivaguru
• Ayala Raul Eduardo
• Yang Zhaohui
• Wang Dejia
• Zhou Yan
• Sivagurunathan Karunagaran
• Sengottaiyan Murugaraja
• Gen Electric

Inventors

• Steele Raymond Douglas
• Kanniappan Sivaguru
• Ayala Raul Eduardo
• Yang Zhaohui
• Wang Dejia
• Zhou Yan
• Sivagurunathan Karunagaran
• Sengottaiyan Murugaraja

Classifications

• C10L1/324

  Dispersions containing coal, oil and water · CPC title

• C10J2300/0903

  Feed preparation · CPC title

• C10J3/506 Primary

  for entrained flow gasifiers · CPC title

• C10J2300/0973

  Water · CPC title

• C10L1/326

  Coal-water suspensions · CPC title