System of automation and control (SAC)
SAC is designed to ensure the plant operation according to the given algorithm in the following setup modes: «setting-up» (manual) and «auto», the control of parameters, protection (switching off) of the station from emergency modes, as well as the information provision about the state of mechanisms to the operator. Type of the SAC is the microprocessor one based on the circuitry of the leading world manufacturers.
SAC ensures:
- control of the main parameters and direction of technological process;
- soft start or frequency regulation of the compressor engine;
- visualization and parameter adjustment of the compressor work with a color-touch control panel;
- emergency automatic shutdown of the station if:
- the technological parameters are outside allowable limits;
- there is a fire or gas in the block of the compressor, for that case the station is equipped with air pollution detection and alarm systems, fire alarm system;
- engaging lock if technological parameters are outside allowable limits;
- emergency ventilation engagement on the premises of the compressor if gas contamination is reached 10% LFL, and emergency station shutdown at 20% of the LFL;
- malfunction alarm by sound and light.
Control boards are installed in separate non-categorical premises (in control room).
For emergency stop of the station with outgassing (in case of fire detecting by operating personnel) application of alarm annunciators “Fire” is provided, which are installed in control room on the door of station control board, in compressor unit, on the unit of inlet valves.
For emergency stop of the station with outgassing (in case of emergency situations not connected with fire) installation of button control stations “Emergency Cutoff” is provided on the door of station control board, and in compressor block. Pressure control is executed on all the points of technological chain having different pressure. Temperature control is executed by all the points of technological chain having different temperature. SAC can be used as a component of CNG filling station as well as in systems of associated gas recovery and in other installations, connected with associated petroleum gas compression.