초록 ▼

Method and apparatus for controlling one or more first compressors (12), through which a compressor feed stream (10) is passed. At least one throttling valve (32) is provided downstream of a compressor recycle line (22), which is provided around the or each first compressor (12) and includes an in-l

Method and apparatus for controlling one or more first compressors (12), through which a compressor feed stream (10) is passed. At least one throttling valve (32) is provided downstream of a compressor recycle line (22), which is provided around the or each first compressor (12) and includes an in-line first recycle valve (24). Sometimes, at least a fraction of the compressor feed stream (10) is selectively allowed to bypass the or each first compressor (12) and the at least one throttling valve, via a bypass line (60). At least one of the throttling valves (32) is automatically controlled using the measurement values of at least one pressure and at least one flow of the group consisting of: the pressure (P1) of the compressor feed stream (10), the flow (F1) of the compressor feed stream (10), the pressure (P2) of the first compressed stream (20) and the flow (F2) of the first compressed stream (20). A first compressor controlled this way may be used in a method of cooling an initial hydrocarbon stream (100).

대표청구항 ▼

1. A method of controlling one or more first compressors at least comprising the steps of: (a) providing a compressor feed stream;(b) passing the compressor feed stream through the one or more first compressors, the or each first compressor having a first inlet and a first outlet to provide one or m

1. A method of controlling one or more first compressors at least comprising the steps of: (a) providing a compressor feed stream;(b) passing the compressor feed stream through the one or more first compressors, the or each first compressor having a first inlet and a first outlet to provide one or more first compressed streams;(c) measuring at least one pressure and at least one flow of the group consisting of: the pressure (P1) of the compressor feed stream, the flow (F1) of the compressor feed stream, the pressure (P2) of the first compressed stream and the flow (F2) of the first compressed stream, to provide at least two measurement values;(d) providing a first compressor recycle line including an in-line first recycle valve around the or each first compressor;(e) passing the or each first compressed stream through at least one throttling valve downstream of the compressor recycle line to provide a controlled stream;(f) selectively allowing a fraction of the or each compressor feed stream to bypass the or each first compressor and the at least one throttling valve via a first bypass line; and(g) automatically controlling at least one of the throttling valve(s) using the measurement values of step (c),wherein the compressor feed stream is provided from a mixed hydrocarbon stream which is separated into a light overhead stream being the compressor feed stream, and a heavy bottom stream, wherein the mixed hydrocarbon stream is expanded in one or more expanders to provide a mixed phase hydrocarbon stream upstream of its separation, and at least one of the one or more expanders and at least one of the one or more first compressors are mechanically interconnected by one or more common drive shafts. 2. The method as claimed in claim 1 wherein the use of the measurements values of step (c) comprises determining the operation of the first compressor relative to its choke line. 3. The method as claimed in claim 1, further comprising the step of: (h) automatically controlling the in-line first recycle valve using the measurements values of step (c). 4. The method as claimed in claim 3, wherein the use of the measurements values of step (c) comprises determining the operation of the first compressor relative to its surge line. 5. The method as claimed in claim 1, further comprising selectively combining a first bypass stream in the first bypass line with the controlled stream. 6. The method as claimed in claim 1, further comprising co-ordinating the measurements of step (c) and the control of step (f) using a controller (XC). 7. The method as claimed in claim 1, comprising measuring at least one of the group consisting of: (i) the pressure (P1) and the flow (F1) of the compressor feed stream;(ii) the pressure (P1) of the compressor feed stream and the flow (F2) of the first compressed stream;(iii) the flow (F1) of the compressor feed stream and the pressure (P2) of the first compressed stream; and(iv) the pressure (P2) and the flow (F2) of the first compressed stream. 8. The method as claimed in claim 1, further comprising the steps of: (j) passing the or each controlled stream through one or more second compressors to provide one or more second compressed streams; and(k) providing a second compressor recycle line, an in-line second recycle valve, and optionally including one or more second compressor recycle coolers. 9. The method as claimed in claim 8, further comprising liquefying at least a fraction of the one or more of the second compressed stream(s), to provide a liquefied hydrocarbon stream. 10. The method as claimed in claim 1, wherein: the compressor feed stream is divided into two or more part-feed streams to pass through two or more first compressors to provide two or more first compressed streams to pass through two or more throttling valves to provide two or more controlled streams; andwherein the steps (b), (e), and (g) are carried out on each part-feed stream, each first compressed stream and each throttling valve. 11. The method as claimed in claim 10, wherein the two or more controlled streams are combined to provide a combined second compressor feed stream to pass through a second compressor. 12. The method as claimed in claim 1, comprising: dividing the mixed hydrocarbon stream into at least two part-streams; and wherein expanding the mixed hydrocarbon stream comprises expanding each of said part-streams through an expander and combining their outflows to provide the mixed-phase hydrocarbon stream. 13. Apparatus for controlling one or more first compressors, the apparatus at least comprising: one or more first compressors to compress a compressor feed stream between a first inlet and a first outlet in the or each first compressor to provide one or more first compressed streams; at least two measurers able to measure at least one pressure and at least one flow of the group consisting of: the pressure (P1) of the compressor feed stream, the flow (F1) of the compressor feed stream, the pressure (P2) of the first compressed stream and the flow (F2) of the first compressed stream; to provide at least two measurement values; a compressor recycle line including an in-line first recycle valve around the or each first compressor; at least one throttling valve downstream of the compressor recycle line to receive the or each first compressed stream to provide a controlled stream; a first bypass line to allow a fraction of the compressor feed stream to bypass the or each first compressor and the at least one throttling valve; and automatically controlling at least one of the throttling valves using the measurements values of step (c), wherein the compressor feed stream is provided from a mixed hydrocarbon stream which is separated into a light overhead stream being the compressor feed stream, and a heavy bottom stream, wherein the mixed hydrocarbon stream is expanded in one or more expanders to provide a mixed phase hydrocarbon stream upstream of its separation, and at least one of the one or more expanders and at least one of the one or more first compressors are mechanically interconnected by one or more common drive shafts. 14. A method of cooling an initial hydrocarbon stream, comprising at least the steps of: (i) passing the initial hydrocarbon stream through a separator to provide a stabilized condensate stream and a mixed hydrocarbon stream;(ii) separating the mixed hydrocarbon stream into a light overhead stream as a compressor feed stream, and a heavy bottom stream; and(iii) passing the compressor feed stream through at least one first compressor to provide a first compressed stream and subsequently through at least one throttling valve, and controlling the first compressor to provide a controlled stream;(iv) passing the controlled stream through at least one second compressor to provide a second compressed stream; and(v) cooling at least a fraction of the second compressed stream to provide a cooled hydrocarbon stream,wherein said controlling of said first compressor to provide the controlled stream at least comprises:(c) measuring at least one pressure and at least one flow of the group consisting of: the pressure (P1) of the compressor feed stream, the flow (F1) of the compressor feed stream, the pressure (P2) of the first compressed stream, and the flow (F2) of the first compressed stream, to provide at least two measurement values;(d) providing a first compressor recycle line including an in-line first recycle valve around the first compressor;(e) passing the first compressed stream through the at least one throttling valve downstream of the compressor recycle line to provide a controlled stream;(f) selectively allowing a fraction of the compressor feed stream to bypass the first compressor and the at least one throttling valve via a first bypass line; and(g) automatically controlling at least one the throttling valve using the measurement values of step (c),wherein the mixed hydrocarbon stream is expanded in at least one expander to provide a mixed phase hydrocarbon stream upstream of its separation, and wherein the at least one expander and the at least one first compressor are mechanically interconnected by a common drive shaft. 15. The method as claimed in claim 14, wherein the use of the measurements values of step (c) comprises determining the operation of the first compressor relative to its choke line. 16. The method as claimed in claim 14, further comprising the step of: (h) automatically controlling the in-line first recycle valve using the measurements values of step (c). 17. The method as claimed in claim 16, wherein the use of the measurements values of step (c) comprises determining the operation of the first compressor relative to its surge line. 18. The method as claimed in claim 14, wherein said cooling of said at least a fraction of the one or more second compressed streams comprises liquefying the at least the fraction of the one or more second compressed streams, and wherein the cooled hydrocarbon stream comprises a liquefied hydrocarbon stream.