AT WORK PREMOS
AT WORK PREMOS SUSTAINABLE ECONOMY 46
Pressing straw into pellets has its price – but also offers a clear added value. At any rate this is how farmer Bernd Pommerehne and agricultural contractor Alexander Marquardt view the process. We visit them at work in Mecklenburg-Vorpommern. A sonorous droning welcomes us on the Bioenergie Lüchow site in Altkalen in the northern German state of Mecklenburg-Vorpommern. In a straw store, a Fendt 1050 rocks steadily at constant revs with its pto powering a Premos 5000 mobile pelleter from Krone. This time the machine is stationary, pelleting in the barn instead of out on the field. A telescopic loader positions big square bales of straw on a side-mounted conveyor belt. The bale twine is automatically cut and rolled up. Slowly, the bales edge along the belt. First, the straw is shaken and loosened before being drawn into the pelleter. At the other end, finished pellets rain steadily into the hopper. Every now and again, a wheeled loader shovels-up around 2 m3 of pellets and piles them at the rear of the store. The resultant heap soon becomes an impressive one. After all, the Premos processes eight to nine 400 kg bales per hour, a throughput of around 3.5 t – a respectable performance, reckons Alexander Marquardt. He’s an agricultural contractor from Warsow, near the state capital city Schwerin. From his home base, one of his 30-strong staff yesterday drove tractor and pelleter almost 130 km to this customer’s site for an early start this morning. Originally planned was processing of around 40 t straw. But customer Bernd Pommerehne, manager of Bioenergie Lüchow, spontaneously decided to process even more straw and to keep the pelleter on-site for two days. “I see a number of advantages for our business in pelleting straw and am therefore interested in trying it out. Everything has gone so well today that I’ve managed to keep it a little longer, which also helps to make the exercise more worthwhile”, he reasons. A NATURAL CYCLE What advantages does Bernd Pommerehne see? First of all, a closer look at his business helps. Bioenergie Lüchow is actually a business group. One part of the group is the biogas plant. This enterprise is a limited liability company producing 1.5 MW power. Bernd Pommerehne and his brothers Carsten and Harald also run a farm together with some 750 ha and an 800 sow and 2000 feeder pig production unit. Aquaculture is another enterprise and the production in this case features African catfish or clarias. Heat from the biogas plant is used as much as possible in the livestock enterprises and a substantial proportion of the electricity produced is fed into the farm network. “Our annual consumption is around 800,000 kWh”, explains Bernd Pommerehne. This symbiotic system reflects his business philosophy to a certain extent. But there’s more. “It is certainly very important for us to achieve as much sustainability as we can. First of all on economic grounds. But also because this approach represents our understanding of agriculture and environmental protection. We think this is what society increasingly wants. And our aim is to fulfil such expectations in real life.” In this way, the waste from cleaning the catfish is processed on the spot into an officially certified feed and this in turn serves as a protein source in the pig units. Manure from the pigs is cycled into biogas production, joining other substrates. Other fermentation inputs currently include a silage of sugar beet and straw. Bought-in dried poultry manure is also used, as is straw from the farm’s own fields. The next stage in the cycle? The residue from biogas fermentation goes onto the fields as nutrition for the next crop. LESS STORAGE NEEDS But how do the straw pellets fit into this policy? The farmer sees a possibility for use in pig feeding: a crude fibre source in rations, for instance, supplementing the wheat bran used up until now. But the pellets could also be useful as “play material” for the animals, to keep them occupied and perhaps less aggressive. A useful and, for him, important 47
