Energy optimization of Grane production facility

Abstract

In order to optimize the design and operation of the Grane process facility and reduce the total energy consumption and CO2/NOX emissions, there is a need to look at ways of optimizing the total energy use. This includes the oil and gas processing facility, the power and heat generation, the flare system and other relevant utilities. Of special interest is to look at waste heat utilization from the gas turbine power generators (heat recovery for power generation and process heat), use of well stream pressure energy, and further options for process integration and efficiency improvement. The objective of the Master thesis is to give an overview and analysis of energy optimization options for the Grane installation, including assessment of the impact on energy use, emissions and operability. The Grane platform biggest power consuming operation is high pressure gas injection process. The compression train requires around 60% of the total power generated by the plant. Through process simulation using HYSYS, the implementation of several optimization options could be made. The minimization of the gas temperature before each compression stages has proved to be effective in the goal of reducing the compression turbine load. Sustainment of the high import gas pressure though increasing the outlet pressure of the 4th stage compressor train could also spare the injection system from unnecessary recompression of the import gas. Through the use of a HRSG unit, the plant would have the capability of powering the entire electrical grid with the use of a single generator turbine. The considerable duty and load reductions lead to significant cuts in emission and fuel costs. Further economical and RAM analysis should be carried out to see if investments in the optimization options are economical viable for the platform.