Israeli company develops small, modular biomass flash-pyrolysis plants

Israeli biomass energy start-up Genova Ltd is building a first pilot plant to demonstrate its innovative power generation concept. The process relies on the gasification of biomass through flash-pyrolysis, with waste heat used to process and dry the feedstock. Interestingly, the design consists of small, modular units with a capacity ranging from 0.5 to 5 megawatts. This allows for the production of bioenergy close to the source of the biomass (more on the many advantages of decentralised production close to waste streams, here and here). Genova will demonstrate its 0.5Mw pilot plant, located in the town of Karmiel (Galilee), with olive stones, an abundant biomass residue with few other markets.

The start-up is partly funded by the government-owned Misgav Technology Center, a technology incubator, and by the Israel Electric Company, the country's state-owned electric utility.

Conventional pyrolysis (chemical change caused by heat) emits residues such as alcohols, ketones, tars, and phenols that are harmful to groundwater supplies, while traditional biomass gasification results in gases with a low caloric value, limiting its practical value.

Genova's patented high-temperature flash-pyrolysis gasifies the biomass and so eliminates the disadvantages of other traditional methods (schematic, click to enlarge). The resulting gases can be burned in gas turbine or gas engines. The company has developed a highly efficient next-generation reactor-pyrolyser, providing pyrolysis process more stable and reliable than other similar processes. Moreover, the system deploys joint mechanical and chemical treatment of raw materials.

Flash-pyrolysis involves heating the biomass rapidly to 800 degrees celsius, the temperature at which its molecules break down. Several gases, including methane and carbon monoxide are then produced which, because they are lighter than air, flow upwards into a standard gas turbine to generate electricity. The other by-product, pyrolysis coke, can be sold for use to power air conditioners or as filters for various substances:
energy :: sustainability :: biomass :: bioenergy :: biofuels :: gasification :: flash-pyrolysis :: efficiency :: Israel ::

According to Yonat Grant, an industrial engineer and CEO of the company, only ten percent of the electricity produced is used to power the process. This claimed 90% efficiency contrasts with the 50% efficiency of more traditional integrated pyrolysis-gasification processes. While the cost of producing a kilowatt with the classic systems is around 9 cents, Genova's cost supposedly is only 2 cents per kilowatt.

The high efficiency and low cost of the system has attracted considerable attention. The Israel Electric Company added a $60,000 investment to the $300,000 it already invested via the Misgav incubator.

Genova's pilot project involves olive waste from the village of Julis, in northern Israel. The feedstock is fed into a converter in order to produce electricity which in turn powers the olive press in a self-sustaining system and dries the biomass. The process is being carried out in a 200 kw/hour plant in the Druze village.

Besides national interest, an investor from California's wine industry will try out the Genova reactor with vineyard waste products. There is also interest coming from Australia, which has a flourishing olive oil industry.

Last year, Genova was included on the Red Herring 100 Europe listing, quite a unique feat, because it was the only environmental technology company (all the rest are 'traditional high tech' (software, communications)), it was the only company currently in a technology incubator, and it was the youngest company (all the other companies have raised millions of dollars). Finally, it was the only company with a female CEO.

Picture: woody olive-stones separated from the pomace, an abundant biomass resource. Credit: Professional Institute of Agriculture and Environment "Cettolini" of Cagliari (Sardinia, Italy).

References:
Israel21c: Turning olive pits into energy - September 25, 2007.

Misgav Technology Center: Description of Genova.