Use beer residue to generate electricity

Waste from breweries can be used to generate electricity, a German biogas expert said.

One of the problems faced by brewers is thousands of tons of grain residues at the end of the brewing process. In the past, companies often sold residues to farmers so that they could feed their animals or farm their fields. However, in recent years Europe has issued strict regulations on the use of waste on agricultural land. In addition, the number of cattle in the old continent is also decreasing. Therefore, beer companies cannot sell all the pulp to farmers as before.

Dry beer residue.(Photo: blogspot.com)

' The situation has become so difficult that in 2000 breweries had to spend a lot of money to bury or destroy beer residues ', technical director Wolfgang Bengel of biogas production company BMP Biomasse Projekt (Germany) told Livescience.

In the process of investigating the problem of headaches for beer companies, Bengel sees business opportunities. He used to get rice husks, rice husks and bagasse to produce electricity from China and Thailand. So he thought that beer residues could also generate electricity to supply beer production lines .

' The brewing process consumes a lot of energy. You must boil ingredients, use plenty of hot water and steam. After that you have to use electricity in the cooling stage. So if you can reduce about 50% of electricity costs thanks to beer residue, that's a big savings ', Bengel explained.

Wet cereal residues and sewage are put into a yeast and bacteria tank. Organic compounds will be decomposed by bacteria to produce methane. This gas and the dry residue from the tank are burned to boil water and create a high pressure steam stream. Steam will turn the turbine to generate electricity.

' With that process, a modern brewery can produce up to 60% of its electricity demand ,' Bengel said.

In order to meet European combustion emission standards, factories only need to install additional filtration and cleaning equipment.

Bengel and his colleagues are trying to convince breweries to adopt technology to produce electricity from beer residues. Plants can purchase equipment and install themselves or waste disposal companies can purchase equipment and then sell electricity to the brewery. Bengel said some companies have sent people to see his test model.