Compact system and method for the production of liquefied natural gas

Abstract

A facility for the production of liquefied natural gas comprising a liquefaction train. The train comprises a plurality of modules to perform the process steps associated with liquefied natural gas production. The train further comprises a primary cooling loop to cool at least a process stream from each module and a first and a second mixed refrigerants against a first coolant comprising clean water. The primary cooling loop is a closed clean water loop, and the cooling is against an ambient temperature. The train further comprises a first plurality of heat exchangers through which the primary cooling loop extends. The cooling is via heat exchange in at least the first plurality of heat exchangers with respect to the first coolant. More than 50% of the first plurality of heat exchangers are printed circuit heat exchangers, which are adapted to provide at least 80% of the cooling against the ambient temperature.

1 . A facility for the production of liquefied natural gas comprising:
 an inside battery limit (ISBL) comprising a liquefaction train, wherein the liquefaction train comprises   (a) a plurality of modules wherein each module being adapted to perform at least one process step associated with liquefied natural gas production, the plurality of modules comprising
 a first module for acid gas removal; 
 a second module comprising a dehydration unit; 
 a third module, being the liquefaction module; and 
 a fourth module comprising equipment for processing of natural gas liquids. 
   (b) a first mixed refrigerant cycle comprising a first mixed refrigerant and a second mixed refrigerant cycle comprising a second mixed refrigerant connected to the liquefaction module for cooling a gas stream to produce the liquefied natural gas;   (c) a primary cooling loop to cool at least a process stream from each module and the first mixed refrigerant and the second mixed refrigerant against a first coolant comprising clean water, wherein the primary cooling loop is a closed clean water cooling loop and the cooling is against an ambient temperature; and   (d) a first plurality of heat exchangers through which the primary cooling loop extends, wherein the cooling by the primary cooling loop is via heat exchange in at least the first plurality of heat exchangers with respect to the first coolant, wherein more than 50% of the first plurality of heat exchangers are printed circuit heat exchangers and wherein the printed circuit heat exchangers are adapted to provide at least 80% of the cooling against the ambient temperature.   
     
     
         2 . The facility of  claim 1 , wherein the liquefaction train further comprises a second plurality of heat exchangers through which the primary cooling loop extend to cool the first coolant by heat exchange with a second coolant, the facility further comprising:
 an outside battery limit (OSBL) comprising a cooler for cooling against the ambient temperature; and   a secondary cooling loop extending through the second plurality of heat exchangers and the cooler to cool the second coolant against ambient temperature, thereby enabling moving of thermal energy from the ISBL to the OSBL for dissipation in the OSBL against the ambient temperature.   
     
     
         3 . The facility of  claim 2 , wherein the second coolant comprising water from a cooling tower system, sea water, or air. 
     
     
         4 . The facility of  claim 1 , wherein each of the plurality of modules of the liquefaction train has a predetermined maximum weight threshold. 
     
     
         5 . The facility of  claim 4  wherein the predetermined maximum weight threshold is 6000 tonnes. 
     
     
         6 . The facility of  claim 1 , wherein for the liquefaction train, the first module having a first side engaging a first side of the second module and the second module having a second side opposite the first side engaging a first side of the fourth module. 
     
     
         7 . The facility of  claim 6 , wherein the liquefaction train further comprises a first module series comprising the first module engaging the second module engaging the fourth module, the first module series being aligned with and arranged adjacent to a second module series comprising the third module arranged between the first compressor on one side and the second compressor on the opposite side. 
     
     
         8 . The facility of  claim 1 , wherein the liquefaction train further comprises:
 a first compressor arranged on a first side of the liquefaction module and connected to the first mixed refrigerant cycle for compressing the first mixed refrigerant; and   a second compressor arranged on a second side of the liquefaction module, the second side being opposite to the first side, and connected to the second mixed refrigerant cycle for compressing the second mixed refrigerant.   
     
     
         9 . The facility of  claim 1 , wherein the liquefaction train further comprises:
 a pre-cool heat exchanger arranged on the first side of the third module and connected to the first mixed refrigerant cycle for pre-cooling the gas stream in heat exchange with respect to the first mixed refrigerant; and   a main heat exchanger arranged on the second side of the third module, the second side being opposite to the first side, and connected to the second mixed refrigerant cycle for at least partially liquefying the pre-cooled gas stream in heat exchange with respect to the second mixed refrigerant.   
     
     
         10 . The facility of  claim 1 , wherein the liquefaction train further comprises a pipe-rack for supporting conduits, the pipe-rack extending through at least the first module, the second module and the fourth module. 
     
     
         11 . The facility  claim 1 , wherein the first mixed refrigerant cycle comprises a single precool heat exchanger. 
     
     
         12 . The facility of  claim 11 , wherein the first mixed refrigerant cycle further comprises a compressor intercooler adapted to cool first mixed refrigerant compressed by the first compressor without condensing the first mixed refrigerant, an outlet of the compressor intercooler being connected to a subsequent stage of the first compressor. 
     
     
         13 . The facility  claim 1 , wherein the liquefaction train has a capacity of production of liquefied natural gas in the range of about 2 to 4 MTPA. 
     
     
         14 . A method comprising the step of producing liquefied natural gas using a facility according to  claim 1 .