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Turn-key projects


2021 03 30

Enerstena has signed a turn-key agreement with AS Vireen in April of 2020. The scope of the agreement is installation of turnkey 5.0 t/h steam boiler house. Boiler is designed to combust animal by-products consisting of 100 % of meat and bone meal (2500 t/year) and it will contribute to circular economy of the facility while utilizing non-recyclable waste side streams for energy production.

In less than 11 months after signing the agreement we are happy to announce that Enerstena has started hot commissioning works. Enerstena’s commissioning team is tuning the process of the plant in order to reach the designed parameters of stable energy production, boiler efficiency and controlled emissions.

Steam boiler’s nominal operating capacity is 5.0 t/h at 12 bar(g). During the commissioning stage the furnace and the boiler is tuned to work in auto regime without constant personnel presence. Minimum load of the steam boiler house is set to 1.5 t/h (30 % of nominal load), furthermore speed of load changes is adjusted to 50 %/hour of boiler’s nominal capacity in automatic mode. These control settings give an opportunity to produce steam energy that can secure a 100 % of facility’s energy demand on variable conditions also with respect to set emission levels. Boiler’s efficiency calculated according EN12953 standard’s indirect method is above 88 % on average.

The main challenge of this project is to combust sophisticated fuel and to ensure allowable emission levels within designed load range. Meat and bone meal has following fuel parameters: LHV 17.6 - 19.5 MJ/kg, moisture content 2.5 - 6.0 % and ash content 18.55 - 21.8 %. Enerstena has developed an innovative tailor-made combustion and control systems which are capable to handle such complex technological processes. This whole development has a huge beneficial impact both economically and environmentally for the Client which is switching from fossil fuels and will generate new income from previously unemployed waste.

Environmentally Enerstena has to fulfill following emission norms: solid particles below 50 mg/Nm³, SO2 below 400 mg/Nm³ and NOx below 500 mg/Nm³ at 6 % of oxygen content on dry basis. Sulphur content of the fuel is 0.35 - 0.6 % and nitrogen content is 7.8 - 9.5 %. Enerstena designed, delivered and implemented state of the art flue gas treatment system and initial emission measurement results during the commissioning process proves the selected technology’s suitability.

Such projects once again demonstrates that synergy between in-house R&D, engineering, solution development and implementation competences in Enerstena Group is a foundation for creating a value to our Clients.