Energy service provider AVA-CO2 Schweiz AG was swift to respond once it became known that Entsorgung Region Zofingen (erzo) had published an international call for tender for the construction of an industrial HTC sludge treatment plant (hydrothermal carbonization) in Switzerland. The criteria were both stringent and exacting, in particular those relating to the water treatment process. As such, the proportion of dissolved organic carbon (DOC) from effluent leaving the treatment plant was set at a maximum of 3 mg per liter, so as to preserve the threshold laid down in local legislation. For AVA-CO2, the DOC load in the HTC process water was barred from exceeding the value of 36.5 kg per day.
AVA-CO2 was successful in all criteria and is now one of two companies that have been given the go-ahead for the planning contract. “We are delighted at the cooperation we have forged thus far with erzo Zofingen and are upbeat about this upcoming project”, says Thomas M. Kläusli, Chief Marketing Officer of AVA-CO2 in Switzerland. The company is working in tandem with Swiss cement manufacturer Holcim to find a solution for the optimal use of HTC coal. The aim is to provide a comprehensive solution for treatment plants that is more environmentally friendly and economically viable.
The final outcome of the call for tender will be made known between April and June of 2014. One thing is already clear, however: erzo Zofingen would be assured of a stable partner if it were to opt for AVA-CO2, as the company not only commissioned the world’s first HTC demonstration facility (HTC-0) in 2010, it constructed the world’s first industrial plant (HTC-1) two years later.
The hydrothermal carbonization process is attracting ever more attention not only in the industry, but also in the world of politics. Rightly so, for the process is as groundbreaking as it is ingenious. For one, it offers manifold advantages such as the ability to process biomass with high water content, often encountered when dealing with effluent sludge. AVA-CO2’s HTC procedure extracts the water from the biomass using heat and pressure, transforming the remaining carbon into high-caliber CO 2-neutral HTC carbon, i.e. ‘AVA cleancoal’. For the purpose, the biomass is heated in pressure vessels to around 220degrees Celsius and ‘baked’ at a constant pressure of 22 bars.
The HTC procedure is eminently robust and makes use of over 90% of the carbon found in the biomass. Thanks to its stability and high energy content, HTC coal may be stored and transported without difficulty. Only the amount of carbon dioxide already present in the biomass is released during combustion. As such, it does not encumber the environment unnecessarily, as would, say the use of fossil fuels. The natural carbonization process takes place over millions of years. The HTC process requires a mere few hours.
Organic residue such as garden waste, liquid manure, biological waste and indeed effluent sludge is not only reused but it also plays an increasingly important role in an era when environmental awareness, climate preservation and the development of renewable energies have increasingly social and economic repercussions.
The company’s ambitions do not stop there, however. Enterprising pioneers of the HTC process are currently developing an efficient procedure to recover phosphorous from effluent sludge during the process of hydrothermal carbonization.
About AVA-CO2
AVA-CO2 offers solutions of global ambit for the sustainable use of biomass in energy generation. In the vanguard of the hydrothermal carbonization process, AVA-CO2 is planning, constructing and operating HTC facilities in which residual plant matter is processed and converted to high-caliber, CO 2-neutral biocoal or CO2-negative biochar. The company is based in Zug and has a number of subsidiaries in Germany.
You can find more information about AVA-CO2 at: www.ava-co2.com
Ursula Reimers from ursula reimers consulting & communications is at your disposal for any further questions.
