The investigation of the internal energy flows has shown that due to the insufficient hydraulics of the existing heating network, the already existing waste heat recovery from the cooling water circuit of the oil refinery cannot be fully utilized. The greatest cost savings were achieved by the recommended conversion to natural gas instead of heating oil.
Possibilities for energy savings in the amount of 13.5 million euros per year were identified. These range from organisational measures to larger investment measures such as the realisation of a natural gas CHP. Measures with immediate or short-term amortisation alone have a savings potential of 6.5 million euros per year.
The analysis of the existing cogeneration plant showed that the operation of the natural gas cogeneration plant is still economical. The use of biomethane would make ecological sense, but is currently not economical. The production of cold from the absorber is only recommended if the heat comes from the CHP. In addition, an electricity/natural gas tender was carried out.
The investigation created the prerequisites for a heating system dimensioned according to requirements. For example, the required heat output of the new system could be reduced from 6,000 to 4,000 kW initially. Compared to the existing heat supply contract, annual savings of more than 100,000 € were possible.
By implementing an innovative steam generation system using CHP, consisting of a conventional steam boiler with micro gas turbine and gas turbine exhaust gas burner, renewal of the steam distribution system with a pure steam generator and a new ventilation system to supply highly hygienic areas, CO2 emissions were reduced by almost 20 %.
