CEG and TSE trial renewable black pellets at Naantali power station in Finland
Torrefaction technology developers and biocoal producers Clean Electricity Generation (CEG) and Turun Seudun Energiantuotanto Oy (TSE) have announced the successful logistics, handling and combustion trial of over 1 000 tonnes of CEG Renewable Black Pellets at TSE’s coal-fired power unit Na2 in Naantali power plant, Finland. The pellets, produced from sustainably sourced biomass, served as a drop-in substitute for fossil coal in the co-firing trial.
The CEG Renewable Black Pellets were produced at CEG’s High-Temperature Torrefaction facility in Derby, UK, and transported by ship to Naantali, Finland. In Naantali, the pellets were stored outdoors, in the power station’s existing coal yard, uncovered and exposed to rain and normal autumn weather conditions.
The pellets were then conveyed, using legacy coal conveyors, to the unit Na2 power block’s coal silos and mills, and ultimately the coal-fired boiler unit Na2.
During the trial, which took place at the end of September 2019, TSE employed the plant’s existing infrastructure designed for fossil coal; the equipment was not modified for biomass. The objectives for the trial were to evaluate the replacement of fossil coal with torrefied pellets, demonstrate that the fuel switch from fossil to renewable can occur without significant investment at the power station, and prove that CEG pellets can withstand outdoor storage for a certain time, in a similar manner to fossil coal.
According to CEG, its CEG Renewable Black Pellets were high-energy and demonstrated hydrophobic behaviour, standard coal handling, efficient combustion, and good grindability. TSE is further evaluating the detailed technical performance of the pellets, as the basis for a fuel replacement decision.
This trial is the latest in CEG’s 2019 programme of customer trials. Utility and industrial trials are underway to secure commodity off-take contracts for Baltania, a commercial-scale Renewable Black Pellet plant in Estonia. Further utility and industrial trials using CEG pellets are planned for Q4 2019 and H1 2020.
CEG will supply eight of its proprietary HTT reactors to Baltania, for a combined output of approximately 160 000 tonnes per annum.