US 12,442,369 B2
Method and system for load control of reciprocating compressors
Zhong-Xiang Zhu, Macungie, PA (US); David M. Espie, Lansdale, PA (US); Graeme Richard Wilson, Surrey (GB); and Gregory W. Henzler, Emmaus, PA (US)
Assigned to AIR PRODUCTS AND CHEMICALS, INC., Allentown, PA (US)
Filed by Air Products and Chemicals, Inc., Allentown, PA (US)
Filed on Aug. 12, 2022, as Appl. No. 17/886,574.
Prior Publication US 2024/0052827 A1, Feb. 15, 2024
Int. Cl. F04B 49/16 (2006.01); F04B 41/06 (2006.01); F04B 49/03 (2006.01); F04B 49/06 (2006.01)
CPC F04B 49/16 (2013.01) [F04B 41/06 (2013.01); F04B 49/03 (2013.01); F04B 49/065 (2013.01); F04B 2205/01 (2013.01); F04B 2205/09 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A process for operating a compression system configured to compress a variable incoming gas feed, the compression system comprising a plurality of parallel compressor trains, each compressor train comprising a plurality of reciprocating compressor stages connected in series, each reciprocating compressor stage having one or more cylinders, the process comprising:
controlling a capacity of the compression system in response to the variable incoming gas feed by:
i) selectively varying a capacity of a first subset of one or more of the compressor trains by continuously varying the capacity of one or more cylinders of each reciprocating compressor stages of the one or more compressor trains of the first subset between a maximum capacity and a minimum capacity; and
ii) selectively varying a capacity of a second subset of one or more of the compressor trains by fully loading or fully unloading one or more cylinders of each reciprocating compressor stages of the compressor trains of the second subset;
wherein the first and second subsets are mutually exclusive, wherein the step of controlling the capacity of the compression system comprises: a) during periods when the incoming gas feed is received by the compression system at a flow between a total maximum capacity of the plurality of compressor trains and a first threshold capacity lower than the total maximum capacity, continuously varying the capacity of the first subset of one or more compressor trains in response to the change in flow of the incoming gas feed, and b) during periods when the incoming gas feed is received by the compression system at a flow between the first threshold capacity of the plurality of compressor trains and a second threshold capacity lower than the first threshold capacity, fully unloading one or more first loaded cylinders of the second subset of one or more compressor trains in response to the flow of the incoming gas feed reducing by an amount equal to the capacity of the one or more first cylinders, or fully loading one or more first unloaded cylinders of the second subset of one or more compressor trains in response to the flow of the incoming gas feed increasing by an amount equal to the capacity of the one or more first cylinders.