How to Capture Methane From a Home Septic System

Human waste can be a source of methane, a flammable gas that can be used for energy.

Instructions

Methane could be used to power a water heater.Methane could be used to power a water heater.
Human waste does not produce as much methane as animal waste; our digestive systems are more efficient and therefore leave less for methane-producing microbes to feed on. Methane can be captured from a home septic system by processing the sludge in the septic tank.

Step 1

Open the septic tank and move sludge from the tank to the heat-safe metal container. Ideally, this container should be somewhat underground to insulate it. Add anaerobic digester bacteria to start a colony there. Close the container.

Step 2

Heat the container. At the right time of year, it can be placed in the sun and left to sit. In colder climates, heaters will need to be installed to keep the contents of the container at a suitable temperature for bacteria growth. The bacteria will consume the sludge and give off methane.

Step 3

Install a pipe that goes from the top of the bacteria container to the compressor. Install a pipe from the compressor to a tank strong enough to hold methane gas under pressure. Periodically, run the compressor to pump methane gas from the metal tank to the gas tank for storage.

Step 4

Use the stored methane with compatible machinery. Heat a water heater with methane. Run a stove with methane.

Things You Will Need

  • Septic system
  • Heat-safe metal container
  • Anaerobic digester bacteria
  • Gas tank
  • Compressor

Tip

  • Execute this project only if there is plenty of space for all the necessary equipment.

Warning

  • Flammable gas under pressure is very dangerous. Be sure to use a storage tank that is in good condition and made for storing gas. Monitor the pressure of the tank regularly.

About the Author

Andrew Ford is a journalist based in Florida. He has contributed to newspapers such as the "Tampa Tribune," "St. Petersburg Times" and "North Florida Herald." Ford is completing his bachelor's degree in journalism from the University of Florida.