Heat Recycling System for Use with a Gasifier

Abstract

The present invention provides a system that recycles heat recovered from hot products of a carbonaceous feedstock gasification process back into the gasification process. The hot gaseous products are used to heat working fluids such as air and water to produce hot air, hot water or steam. The heated fluids are used to return heat back to the gasification process. The system also comprises a control system to optimize the efficiency of a gasification process by minimizing energy consumption of the process, while also maximizing energy production.

1 . A system that recycles heat recovered from a hot gas to a carbonaceous feedstock gasifier, the system comprising: 
 means to transfer the hot gas to a gas-to-fluid heat exchanger, where the heat from the hot gas is transferred to a fluid to produce a heated fluid and cooled gas;    means to transfer the heated fluid to the gasifier; and    a control system comprising sensing elements for monitoring operating parameters of the system, and response elements for adjusting operating conditions within the system to optimize the gasification process;    wherein the response elements adjust the operating conditions within the system according to the data obtained from the sensing elements, thereby optimizing the efficiency of a gasification process by minimizing energy consumption of the process, while also maximizing energy production.    
     
     
         2 . The system according to  claim 1 , wherein the hot gas is a gas produced during a carbonaceous feedstock gasification process.  
     
     
         3 . The system according to  claim 2 , wherein the fluid is air, water, oil, nitrogen or carbon dioxide.  
     
     
         4 . The system according to  claim 3 , wherein the fluid is air, and the gas-to-fluid heat exchanger is a gas-to-air heat exchanger.  
     
     
         5 . The system according to  claim 3 , wherein the fluid is water, and the gas-to-fluid heat exchanger is a heat recovery steam generator.  
     
     
         6 . A system that recycles heat recovered from a hot gas to a carbonaceous feedstock gasifier, the system comprising: 
 means to transfer the hot gas to a gas-to-air heat exchanger, where the heat from the hot gas is transferred to air to produce a heated air and a cooled gas; and    means to transfer the heated air to the gasifier.    
     
     
         7 . The system according to  claim 6 , wherein the hot gas is a gas produced in a gasifier during a carbonaceous feedstock gasification process.  
     
     
         8 . The system according to  claim 6 , wherein the means to transfer the hot gas to the gas-to-air heat exchanger comprises a hot gas conduit system providing fluid communication between a hot gas outlet on the gasifier and a hot gas inlet on the gas-to-air heat exchanger, and the means to transfer the heated air to the gasifier comprises an air conduit system providing fluid communication between an air outlet on the gas-to-air heat exchanger and an air inlet on the gasifier, wherein the hot gas is transferred from the gasifier to the gas-to-air heat exchanger through the hot gas conduit, and the heated air is transferred from the gas-to-air heat exchanger through the air conduit system into the air inlet the gasifier.  
     
     
         9 . A process for improving the efficiency of a carbonaceous feedstock gasification process by recycling sensible heat from a hot gas produced by the gasification process back into the gasification process using a gas-to-fluid heat exchanger comprising a hot product gas inlet in communication with a cooled product gas outlet, and a cool fluid inlet in communication with a heated fluid outlet, the process comprising the steps of: 
 passing the hot product gas through the hot product gas inlet into the gas-to-fluid heat exchanger;    passing the cool fluid through the cool fluid inlet into the gas-to-fluid heat exchanger;    transferring heat from the hot product gas to the cool fluid via the gas-to-fluid heat exchanger to produce a cooled product gas which exits the heat exchanger via the cooled product gas outlet, and a heated fluid which exits the heat exchanger via the heated fluid outlet; and    using the heated fluid to provide heat for the carbonaceous feedstock gasification process.    
     
     
         10 . The process according to  claim 9 , wherein the fluid is air, and the gas-to-fluid heat exchanger is a gas-to-air heat exchanger.