Method and System for Ultra-Low Emissions of Natural Gas Storage and Redeployment

Abstract

The disclosed subject matters include a system and method of storing and redeploying a gaseous fuel with low vapor emissions. An exemplary method includes a dehydration and liquefaction of a gaseous fuel, a pressurization storage and vaporization of the liquid fuel on demand. The method may further include an automation and monitoring.

What is claimed: 
     
         1 . A system for storing and redeploying a gaseous fuel, comprising:
 a dehydration unit configured to at least partially dehydrate the gaseous fuel,   a liquefaction unit configured to liquefy the gaseous fuel,   a pressurized storage unit configured to store the liquefied gaseous fuel, and   a vaporization unit configured to vaporize the liquified gaseous fuel,   wherein the pressurized storage unit is configured to control temperature and pressure therein to avoid operationally detrimental freezing of the liquefied gaseous fuel.   
     
     
         2 . The system of  claim 1 , wherein the temperature of the pressurized storage unit is maintained at or below the bubble point temperature of the gaseous fuel and between about 200 ka (29 psia) to about 4,480 kPa (650 psia). 
     
     
         3 . The system of  claim 1 , wherein the pressure of the pressurized storage unit is maintained from about 200 ka (29 psia) to about 4,480 kPa (650 psia). 
     
     
         4 . The system of  claim 1 , further comprising an automation unit for controlling one or more parts of the system. 
     
     
         5 . The system of  claim 1 , wherein the gaseous fuel substantially includes methane. 
     
     
         6 . The system of  claim 1 , wherein the system is configured for no direct, intentional or continuous vapor emissions to the atmosphere other than fugitive emissions. 
     
     
         7 . A method of storing and redeploying a gaseous fuel, comprising:
 dehydrating a gaseous fuel,   liquefying the gaseous fuel,   pressurizing the gaseous fuel for storage as a liquefied fuel,   vaporizing the liquefied fuel to form a vaporized fuel, and   redeploying the vaporized fuel,   wherein the liquefied fuel is pressurized and stored at a combination of temperature and pressure that avoids operationally detrimental effects of freezing of any of the components in the liquefied fuel.   
     
     
         8 . The method of  claim 7 , wherein the vaporizing primarily uses heat from ambient heat sources, direct or indirect electricity, or a combination thereof. 
     
     
         9 . The method of  claim 7 , wherein the method is performed using power only from electricity, and not from combustion or emission-causing process. 
     
     
         10 . The method of  claim 7 , further comprising defrosting a cryogenic chilling equipment of any deposited solid CO 2 . 
     
     
         11 . The method of  claim 10 , wherein the defrosting is performed by a cycle operation. 
     
     
         12 . The method of  claim 10 , wherein the defrosting is performed by cycling more than one parallel chilling equipment. 
     
     
         13 . The method of  claim 7 , wherein contaminates are accumulated in a storage volume and returned to vapor or liquid when the storage volume is subsequently warmed. 
     
     
         14 . The method of  claim 7  wherein the electricity used for the dehydration, liquefaction, storage and vaporization processes is at a lower carbon intensity than the electrically generally available from regional electricity supplies. 
     
     
         15 . The method of  claim 14 , wherein a timing of purchasing electricity is optimized to yield a lower carbon intensity then generally available from regional electricity supplies, even if the supply is coming from said regional electricity supplies. 
     
     
         16 . The method of  claim 7 , wherein fugitive emission is detected by a plurality of methane-in-air detection devices. 
     
     
         17 . The method of  claim 16 , wherein the methane-in-air detection devices are communicatively coupled to an automation unit. 
     
     
         18 . The method of  claim 17 , wherein the methane-in-air detection devices are deployed from land vehicles, drone, aircraft, and satellites, and communicatively coupled to an automation unit. 
     
     
         19 . The method of  claim 14 , wherein the purchasing of electricity and natural gas uses real time price information to optimize the cost intensity of the storage using automated and or semi-automated methods. 
     
     
         20 . The method of  claim 19 , wherein automated souring of electricity and natural gas is based, at least in part, on machine learning and artificial intelligence. 
     
     
         21 . The method of  claim 7 , wherein the gaseous fuel is only taken for storage when its composition is below the freezing saturation. 
     
     
         22 . The method of  claim 1 , wherein CO 2  concentration is reduced by means of a membrane, chemical solution, or solid absorbent and the residue stream being compressed and sent to gas consumers. 
     
     
         23 . The method of  claim 1 , wherein CO 2  concentration is reduced by means of a membrane, chemical solution, or solid absorbent and the residue stream is sent to sequestration. 
     
     
         24 . The method of  claim 7 , wherein the vaporizing primarily uses heat from waste heat sources. 
     
     
         25 . The method of  claim 7 , wherein the vaporizing primarily uses heat from low carbon intensity electricity. 
     
     
         26 . The system of  claim 1 , further comprising at least a safety pressure relief device that practically minimizes hydrocarbon leakage into the pressure safety header. 
     
     
         27 . The system of  claim 26 , wherein at least a rupture disk is incorporated for safety pressure relief. 
     
     
         28 . The system of  claim 27 , wherein the rupture disk and pressure safety device are incorporated in series for safety pressure relief. 
     
     
         29 . The system of  claim 1 , further comprising at least a safety pressure relief device operated without purge gas comprising natural gas. 
     
     
         30 . The system of  claim 29 , further comprising at least a mechanical element of the safety pressure relief device to withstand the overpressures from deflagration events. 
     
     
         31 . The system of  claim 1 , where there is no combustion equipment aside from pilot(s) at the end of safety pressure relief device. 
     
     
         32 . The system of  claim 1 , further comprising a vapor management device. 
     
     
         33 . The system of  claim 32 , wherein the vapor management system has at least a header operating at different pressures. 
     
     
         34 . The system of  claim 32 , wherein the vapor management system is configured to route vapor from maintenance depressing. 
     
     
         35 . The system of  claim 32 , wherein vapor in the vapor management system is routed to downstream gas consumers without the need for compression. 
     
     
         36 . The system of  claim 32 , wherein vapor in the vapor management system is compressed and routed to downstream gas consumers. 
     
     
         37 . The system of  claim 32 , where vapor in the vapor management system is condensed with a supplemental refrigeration and returned to the pressurized storage.