Biobased pyrolysis as key technology

Empyro started as a European innovation project in 2009, aiming at bringing about polygeneration through pyrolysis. Polygeneration is a process that produces oil, steam, electricity and organic acids simultaneously. Additionally, the innovation project set the goal to recover acetic acid from one of the fluids produced during the production of pyrolysis oil. The project was completed in 2015 with the construction of the 25-megawatt polygeneration pyrolysis plant in Hengelo for the simultaneous production of electricity, steam and fuel oil from woody biomass. The design was made in cooperation with well-known industrial companies in Twente, such as Stork Thermeq, AkzoNobel, Zeton en HoSt.

The produced fuel oil is sold, exported or used locally. The biomass supply is organised locally in Twente with a specialised supplier. Part of the Empyro plant is set up for process demonstrations to test different types of raw materials, and to test the extraction of organic acids from biomass. Empyro has extensive knowledge on biomass supply, conversion processes in the factory, storage of pyrolysis oil and application possibilities in sustainable end products, and demonstrates this to numerous sectors and industries. Aside from sustainable fuel, the factory also produces steam and electricity. AkzoNobel’s neighbouring salt plant uses the steam, and the electricity is sold to the electricity grid. The pyrolysis oil is the main commercial product for Empyro.

Pyrolysis oil is a so-called second-generation biofuel because it is manufactured from various types of non-food biomass, including waste wood and prunings. It, therefore, contributes to reducing the greenhouse gas effect while not competing with crops used in the food chain. Pyrolysis oil has various advantages compared to solid biofuels: it is easy to transport, store and use. Additionally, it is compatible with existing infrastructure for fossil fuels as it can be burned in boilers and gas turbines. Pyrolysis oil can be used as a replacement for liquid fuels, including fuel oil, diesel and palm oil. Therefore, it can be used in district heating networks instead of natural gas, and in gas turbines to produce electricity and high-quality steam efficiently. Other valuable liquids can be extracted by using biorefining.