Arrangement and Method for Treatment of Compressed Gas

Abstract

An arrangement for use with a liquid cooled and/or lubricated compressor ( 10 ) for compressing gas, and incorporating provision to add liquid for cooling purposes to the gas prior to entry of the gas into the compressor, in which down stream of the compressor there is a liquid/gas separator ( 11 ) to separate the liquid from the gas and in which there is means ( 29 ) to recover heat from the liquid, and in which there is at least one filter ( 17 or 18 ) in the gas stream downstream of the liquid/gas separator, and there is a heater ( 19 ) in the gas stream downstream of the filter in which the gas is heated using heat recovered from the liquid (at 29 ), whereby to regulate the temperature of the pressurised gas. There may be a heat exchanger (14) between the separator and the filter There may be a refrigerant dryer group ( 15 ) arranged to cool the gas after the liquid has been separated from the gas and before the gas is passed through the filter

1 . A arrangement for use with a liquid cooled and/or lubricated compressor ( 10 ) for compressing gas, and incorporating provision to add liquid for cooling purposes to the gas prior to entry of the gas into the compressor, 
 characterised in that downstream of the compressor there is a liquid/gas separator ( 11 ) to separate the liquid from the gas and in which there is means ( 29 ) to recover heat from the liquid, and in which there is at least one filter ( 17  or  18 ) in the gas stream downstream of the liquid/gas separator, and there is a heater ( 19 ) in the gas stream downstream of the filter in which the gas is heated using heat recovered from the liquid, whereby to regulate the temperature of the pressurised gas preferably for passing the gas to a gas-gas separation unit.    
   
   
       2 . An arrangement as claimed in  claim 1 , 
 characterised in that there is a heat exchanger ( 14 ) in the gas stream between the liquid/gas separator and the at least one filter, and in that heat exchanger cooling medium from an external source is used to cool the gas stream.    
   
   
       3 . An arrangement as claimed in  claim 1  or  claim 2 , 
 characterised in that there is a refrigerant dryer group ( 15 ) arranged to cool the gas after the liquid has been separated from the gas, and before the gas is passed through the at least one filter.    
   
   
       4 . An arrangement as claimed in any one of the preceding claims, characterised in that the at least one filter is a coalescing particle filter.  
   
   
       5 . An arrangement as claimed in any one of  claims 1  to  3 , characterised in that the at least one filter is a carbon filter for removal of vapour from the cooling liquid.  
   
   
       6 . An arrangement as claimed in any one of  claims 1  to  3 , 
 characterised in that the at least one filter includes two stage filtration, the first filter stage comprising a coalescing particle filter, and the second filter stage comprising a carbon filter for removal of vapour from the cooling liquid.    
   
   
       7 . An arrangement as claimed in any one of the preceding claims, in combination with a membrane gas separator unit arranged to receive gas from the arrangement using the heat recovered from the liquid prior to the liquid passing through the filter.  
   
   
       8 . An arrangement as claimed in any one of the preceding claims, in combination with a compressor for compressing the gas.  
   
   
       9 . An arrangement as claimed in  claim 8;   characterised in that the compressor is a screw compressor.    
   
   
       10 . An arrangement as claimed in  claim 9 , 
 characterised in that the compressor is cooled and lubricated by oil.    
   
   
       11 . A method of recovering heat from a compressed gas from a liquid cooled and/or lubricated compressor, and comprising the steps of adding liquid for cooling purposes to a gas prior to the gas entering into the compressor, separating liquid from the gas after the gas has left the compressor, recovering heat from the liquid, passing the gas through at least one filter, and, downstream of the filter, using heat recovered from the liquid before the gas passed through the filter to heat the gas, whereby the regulate the temperature of the pressurised gas.