Resources in our community.
Every cow produces 200 Watts of power every day. This power is washed out of the dairy barns each day in vast quantities of water. This creates a huge problem in the ecosystem. The liquefied manure sinks rapidly into the soil contaminating the underlying aquifer.
Yet with the right digester one can produce methane gas (simplest), Bio-fuels such as diesel, alcohol even Crude oil Research on pigs.
Methane can be used directly in a Natural Gas converted electrical generator. Methane is the primary gas in Natural Gas. It can be compressed and used in trucks cars tractors ect. Piped into your house for use in heating or cooking. The simplest version is a plastic bag buried in the ground with a gas line attached. This system is used in Mexico. India uses a steel bell jar in a slurry pit. The weight of the bell jar compresses the gas for transport. Indian methane production example. On the other end of the scale is Fair Oaks Farms
A short list of links
Diesel and Alcohol are a bit more complex.
They require special algae to create. More processing is required than for Methane. But systems have been installed around the world and produce vast amounts of fuel from this valuable resource.
The remaining organic materials can then be added as a solid. As had the water reclaimed for use in the dairy. There are more nutrients to return to the soil in digestion than in Gasification. Solid manures work way better for soil augmentation as it dose not wash down to the water table. Staying in the upper soil for plant utilization.
Liquid manure may work well in distillation processes. Where the desired gaseous components can be separated via a refracting tower.