To combat energy shortages in rural Brazil, Firestone EPDM Geomembrane was selected for several biodigester projects, as both the lining and digester cover material. Firestone EPDM Geomembrane makes an ideal dome for these biodigesters because of its amazing elasticity characteristic, stated Luiz Prado, manager, Ecosys Biodigestores, Sao Paolo, referring to the membranes ability to elongate over 300 percent.
The membrane’s elongation properties, along with its easy of installation and maintenance were contributing factors to the product selection, as was the color of the membrane. Because of the membranes black color, it is ideal for attracting the suns heat and maintaining the high temperatures required to produce high amounts of biogas, while being resistant UV damage.
The digesters ranged in size from 88 long x 33′ wide to 177 long x 16 wide. All units were 11.5 to 13′ high, from the floor to peak of the digester at maximum capacity. The digesters provide several benefits including:
efficient utilization of animal and human waste products
reduction in the emission of greenhouse gases
increased odor control
production of a highly effective biofertilizer, which significantly increases rural productivity
production of biogas, a renewable energy source, that can be used in place of natural gas or liquefied petroleum