Compressor startup

A system comprising:

• an inlet flowline configured to flow a process gas;
• a suction throttling valve installed on the inlet flowline, the suction throttling valve configured to control flow of the process gas through the inlet flowline;
• a compressor downstream of the suction throttling valve, the compressor configured to pressurize the process gas;
• an outlet flowline configured to flow the process gas from the compressor;
• an anti-surge flowline branching from the outlet flowline and connected to the inlet flowline intermediate of the suction throttling valve and the compressor;
• an anti-surge control valve installed on the anti-surge flowline, the anti-surge control valve configured to control flow of a first portion of the process gas from the outlet flowline through the anti-surge flowline to the inlet flowline;
• a bypass flowline branching from the anti-surge flowline and connected to the inlet flowline upstream of the suction throttling valve, the bypass flowline providing an alternative flow path for a second portion of the process gas flowing through the anti-surge flowline to the inlet flowline around the suction throttling valve;
• and
• a bypass control valve installed on the bypass flowline, the bypass control valve configured to control flow of the second portion of the process gas from the anti-surge flowline through the bypass flowline to the inlet flowline around the suction throttling valve.

A system comprising:

• an inlet flowline configured to flow a process gas;
• a suction throttling valve installed on the inlet flowline, the suction throttling valve configured to control flow of the process gas through the inlet flowline;
• a compressor downstream of the suction throttling valve, the compressor configured to pressurize the process gas;
• an outlet flowline from the compressor;
• an anti-surge flowline branching from the outlet flowline and connected to the inlet flowline intermediate of the suction throttling valve and the compressor;
• an anti-surge control valve installed on the anti-surge flowline, the anti-surge control valve configured to control flow of a first portion of the process gas from the outlet flowline through the anti-surge flowline to the inlet flowline;
• a bypass flowline branching from the anti-surge flowline and connected to the inlet flowline upstream of the suction throttling valve, the bypass flowline providing an alternative flow path for a second portion of the process gas flowing through the anti-surge flowline to the inlet flowline around the suction throttling valve;
• a bypass control valve installed on the bypass flowline, the bypass control valve configured to control flow of the second portion of the process gas from the anti-surge flowline through the bypass flowline to the inlet flowline around the suction throttling valve;
• and
• a controller communicatively coupled to the compressor, to the suction throttling valve, to the anti-surge control valve, and to the bypass control valve, the controller comprising:
• one or more processors;
• and
• a non-transitory computer-readable storage medium coupled to the one or more processors and storing programming instructions for execution by the one or more processors, the programming instructions instructing the one or more processors to perform operations comprising:
• determining a compressor rotation speed of the compressor;
• comparing the compressor rotation speed with a specified rated speed;
• and
• transmitting a close signal to the bypass control valve in response to determining that the compressor rotation speed has reached the specified rated speed.