Grass, a valuable feedstock for the biobased economy

We should take another view of grass, according to Grassa. Cows in meadows are beautiful, but grass contains too much proteins for the cow. Why not extract that excess first? Besides, grass contains many valuable substances like fibres and sugars, which could be marketed separately. Grassa puts this philosophy into practice.

Grassa’s history and that of grass biorefinery starts in 1993 when Dutch potato farmers’ collective AVEBE employs Johan Sanders as the head of its R&D department. CEO Poutsma asks him to come up with smart ideas for the inter harvest period. Sanders: ‘Poutsma’s problem that his competitors (wheat and maize starch companies) could produce all year round, while the potato harvest period merely ran from September to April. Potato starch factories lay idle half of the year, which means double unit capital costs when compared to competitors.’

Less proteins to the cow, less ammonia in manure
Sanders’ previous employer was Gist-brocades (nowadays a DSM division), from which he had contributed to a semi-official report on ‘radical reductions in minerals use in Dutch cattle breeding’. ‘Prevention is better than end-of-pipe solutions’ was the reports’ message. Which would mean in this case: use national mineral feedstock for proteins in pig fodder, and reduce protein and amino acid inputs to cows which only need one quarter of grass proteins themselves, and excrete the remainder. This would greatly reduce ammonium production from manure. For this solution, we need grass biorefinery.

Pressing and milling fresh grass (80-90% water), and extracting fibres (30% of dry matter), will produce a juice not unlike potato juice. It contains proteins (15-20%), amino acids, organic acids (5%), sugars (27%), and minerals (10%). AVEBE could use all these components; it isolated proteins from potatoes from the ‘80s onwards. Processing grass juice would put to use AVEBE’s equipment in the inter harvest period from April to mid-August.

Grass refinery was a contended project within AVEBE. It is a cooperative of potato farmers, and grass processing would not be within its traditional area. New managers came up with new priorities. Yet, a pilot installation could be constructed at AVEBE under the name of Prograss, a project to which Harry Garrelts of NOM (development agency for the Northern provinces) contributed greatly.

But finally, counter forces won. AVEBE reduced its number of potato starch mills from four to two, and the inter harvest period became ever shorter. Original partners Nedalco and Mommersteeg withdrew from the project. Although Rabo bank joined in, together with ABCTA and ACM/Agrifirm, AVEBE wanted to withdraw from the project and sell the knowledge. Upon which the others decided to stop the project.

In Gjalt de Haan’s shed
Grass refinery starts a new life in 2005 as Carel de Vries from Courage (a foundation stimulating innovations in dairy farming) takes an interest in small-scale grass processing. He takes the initiative to construct a small-scale mobile test unit together with Gjalt de Haan, who heads Hoogland, one of the few agricultural supply agencies in the grass sector. They start in Gjalt de Haan’s shed and form a consortium of Northern Dutch small and medium sized enterprises: apart from Courage and Hoogland also a machine factory (PMF), a fodder company (Beuker), a cardboard company (ESKA), and later also Sanovations, Johan Sanders’ private company. His son Constantijn Sanders becomes the R&D officer.

The mobile test unit, fitting into three containers, is operative from September 2011 onwards. It separates grass into fibres and proteins. The remaining grass juice is returned to the land as yet; but upon further development Grassa plans to extract more components from it, like amino acids, organic acids and sugars. The great advantage of this setup is that Grassa has a sound business case just on the basis of fibre and protein extraction, because there is no need to transport grass to a central unit for processing. And no need to transport the juice back to the land. At a later stage, grass juice can be valorised further. And there are more opportunities: beet leaves, carrot and tomato leaves, and road side and park grass.

The breakthrough
The small-scale mobile unit was the breakthrough. Grassa is a young company and can develop itself in many ways. It could try to find direct applications for today’s products: fibres and grass proteins. Proteins might not just be used for fodder, but for human food as well, just like soy proteins in soy drinks and rice proteins in rice ‘milk’. Fibres need improvement for application in paper and pulp. Meanwhile, grass juice can be further processed for chemicals production. Scaling up should stay in tune with development of new markets. New venture’s histories indicate that this is the most risky phase. But sound principles like Grassa’s are the first step on the road to success. There is a lot of grass around in the Northern part of the Netherlands.

For the realization of the biobased economy, chemistry and agriculture should cooperate, in order to valorise agricultural waste streams. Chemical industry does give that a thought, but feels that agriculture had not yet started to do so. Grass refinery is one of the first Dutch activities from the agro world to which chemistry could join in. An example to other agricultural producers. And to the rest of Europe.

Courtesy NOM, development agency for the Dutch Northern provinces

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