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Biogas Recovery

Landfill gas recovery
Three methane gas recovery facilities, owned by Montauk Energy Capital, operate on the landfill. The first plant opened in 1986, then the second opened in 1995, and the third opened in 2007. These facilities convert the methane gas into natural gas. The plants can recover about 15 million cubic feet per day (420×103 m3/d) of landfill gas, making it the largest recovery operation of its kind in the world. Distributed by Duke Energy Corporation, the natural gas energy from the natural gas from the three facilities combined is enough to power 25,000 homes and businesses.
(Source: Wikipedia.org)

CO2 recovery systems in brewery
CO2 recovery plants of are the result of many years' experience and continuous development, based on comprehensive know-how relating to brewing technology and refrigeration engineering.

CO2 recovery
Due to extract degradation, alcohol, yeast and also a considerable amount of fermentation carbon dioxide are produced during the fermentation process. At the same time, CO2 with a very high degree of purity is indispensable for the production process in a modern brewery, which meet all requirements of efficient carbon dioxide treatment: maximum purity with lowest O2 content and maximum yield.

In several steps the carbon dioxide is purified thoroughly. From the fermentation tanks the CO2 is first led to the foam separator. In this stage, the foam entrained from the fermentation tanks is separated. Through a low-pressure gas storage balloon the gas flows into the gas scrubber, where it is cleaned by counterflow of water. In the gas scrubber water-soluble impurities and aerosols are absorbed from the carbon dioxide.

After the CO2 compressor the drying unit of the CO2 recovery plant is installed. It consists of two adsorption tanks filled with drying agent. In order to remove the residual moisture from the gas, the carbon dioxide flows through one tank while the other tank is regenerated. In the gas purifier, installed after the drying unit and also consisting of two vessels, substances influencing odour and taste are removed.

With identical plant design, the only difference between the purifier and the dryer is the filling with activated carbon. In the next phase the CO2 is liquefied in a shell and tube heat exchanger and inert gases like O2 and N2 are removed. All stages of purification in a Huppmann CO2 recovery plant will be precisely adjusted to the specific requirements of a brewery, taking into consideration technological and financial aspects. By compression and condensation the storage volume is reduced to such an extent that temporary storage of even very large quantities of carbon dioxide requires little space.

The first step of volume reduction is a two-stage compression. With a dry-running piston compressor the fermentation carbon dioxide is compressed to one sixteenth of the original gas volume. The compressed gas is liquefied in the condenser and then collected in a storage tank. Thus, the brewer can collect the carbon dioxide produced during fermentation over several days and can then use it for the production process as required.

(Source: www.geabrewery.com)