One Millionth Tonne Milestone

Esken Renewables, as the UK’s leading biomass fuel provider, reached a remarkable milestone in 2023: processing its one millionth ton of waste wood. This significant achievement was made possible by the HAAS waste wood plant installed in 2017. This milestone and joint success for Esken Renewables and HAAS Recycling-Systems provides an opportunity to look back on the history of the facility.

Esken Renewables has long-term contracts to supply 1.7 million tonnes of fuel to biomass plants each year. The renewable energy generated is equivalent to the annual domestic electricity needs of 2% of the UK population.

The core business is to supply biomass fuel, which is derived from wood waste and delivered to a large number of power plants. The waste wood fuel helps the UK avoid emissions equivalent to taking 135,746 cars off the road for a year.

In 2015, Esken was challenged to supply the biomass for the waste wood-fuelled Tilbury Green Power (TGP) power plant. The Renewable Biomass power plant has a capacity of around 40 megawatts (MW) and produces up to 319,000 MWh of renewable electricity per year – enough to supply around 97,000 households. At full capacity, the Renewable Biomass power plant requires around 270,000 tonnes of waste wood per year.

In November 2015, Esken Renewables, previously known as Stobart Energy, commissioned HAAS to supply a plant for the processing of untreated waste wood to high-quality recycled wood chips. The objective was to supply a plant that could guarantee throughput rates of 60 tonnes per hour, processing untreated waste wood into high-quality recycled wood chips. A 100% redundancy was required, in order to prevent down times.

The solution was installed right next to the TGP power plant in January 2017; a HAAS waste wood processing plant with two identical lines. Each line has a guaranteed throughput capacity of at least 60 t/h. The total output of the twin line plant is an outstanding 120 t/h. The end product is high-quality recycled chips < 100 mm, ideal for the production of renewable energy.

The incoming waste wood, which is containing impurities, is shredded with the TYRON pre-shredder followed by the ARTHOS secondary shredder. State-of-the-art magnet and eddy currents separate ferrous and non-ferrous parts, thus removing a large proportion of the impurities from the biomass. Air separators guarantee the extraction of heavy material such as stones and glass.

Dust extraction and filtration systems perfectly matched to the processing line keep the installation nearly dust free. The dust extraction system reduces the dust around the plant and the building to a minimum, which is not only an advantage for working conditions, but also for fire and explosion protection.

A spark detecting and extinguishing system is in place, using state-of-the-art sensor technology to monitors the treatment process- rounds off the scope of delivery.

The cleaned chips are finally separated into three fractions:

• The fine fraction < 5 mm is transported together with the wood dust from the filter systems to the truck loading station and loaded onto high cube trailer.
• The medium fraction 5 – 100 mm is transported directly to the chip storage bunker of the neighbouring biomass power plant.
• The oversize > 100 mm is fed back into the shredding circuit.

The HAAS processing technology is characterised by its high reliability. The plant is extremely low-maintenance. In five years of continuous operation and 1 million tonnes of processed waste wood, there was not even one extended damage-related downtime.

The installation of the plant was completed in August 2017 and commissioning began. At the beginning of September, the plant was officially handed over to Esken Renewables after successful commissioning. Since then, up to 800 tonnes of high-quality recycling chips have been produced daily for thermal utilisation.

“At Esken Renewables, we invest in skilled and dedicated people, and also in best-in-class infrastructure and cutting edge technology to ensure that we maximise the financial and environmental benefits at every stage of the process of transforming waste into renewable energy.

At the time, we were faced with the challenge of supplying biomass for Tilbury Green Power station. At least 60 tonnes per hour of untreated waste wood had to be processed into high-quality recycled chips. 100% redundancy was required to prevent downtime. Together with HAAS, we solved this challenge in the best possible way. We generate top performance and can always rely on the quality of the HAAS plant. Apart from the usual regular service visits, hardly any additional maintenance/repairs were necessary. We are very satisfied and would choose a HAAS system once again.”

Aaron Whitrow, Head of Operations Esken Renewables