UEM has the experience and ability to offer small scale water and waste solutions for rural areas with small and dispersed populations. UEM has the technical expertise to offer distributed, single family or single village solutions for water treatment, wastewater treatment, and solid waste treatment.
UEM is currently executing a small scale anaerobic digester project for a farm in Vermont, USA for the digestion of dairy cattle manure. With the installation of the digester, the farm will enhance its manure management practices and reduce its environmental impact by reducing odors, pathogens, organic pollutants, and greenhouse gases that are generated from the manure wastewater. Since anaerobic digestion is a net energy positive process, the farm will generate power for use on the farm in the form of both electrical and thermal energy. The farm will get credit for the electricity that is generated through local net metering laws.
The digested wastewater exiting the digester will be dewatered in a solids separating system, and the dewatered solids will be used as animal bedding on the farm. Any excess dewatered solids not used as bedding will be sold as soil amendment. The liquid from the solids separation system will be land applied as liquid fertilizer. The digester will not only improve the environmental quality of the surrounding area, but create an additional source of revenue for the farm resulting from the electricity, thermal energy, and separated solids generated as by-products of the manure digestion process.
The digester will be a complete mix digester installed partially underground. The digester is designed to treat 23,000 liters per day of manure wastewater in a large volume digester tank (i.e., 40 day HRT). The digester liquid volume will total 910,000 gallons. The expected biogas production will be sufficient for producing 50 kW continuous of electric power. The anticipated useful thermal energy produced from the cogeneration system is up to 6,500 MJ per day. UEM was involved in the entire life-cycle of this project, including assisting the farm in securing grants and subsidies.
UEM has also designed a prefabricated digester for small scale (i.e. <5 cattle) dairy farms that can be deployed with a short lead time. These small scale digesters will generate methane rich biogas that can be used as a cooking fuel and can replace purchased gas or biomass. UEM has installed these small scale digesters in Haryana, India.