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Madison-Chatham Joint Meeting

Methane Recapture

methane signIn addition to treating the wastewater, our sewage plant also processes the residual solid-waste material.  These solids are placed in a 'digester' or large holding tank.  This tank acts like a stomach and using bacteria digests the solid material in a process known as anaerobic digestion.  During the process, methane is recaptured and used to run large diesel engines at the plant. 

A picture of the one of our sewage treatment plant's 'duel fuel' diesel engines is below and to the right.  This engine runs on both natural gas and methane diesel enginegas that is recaptured in the plant's digester.

Sustainability involves three parts...planet, profit and people. Treating wastewater is very energy intensive, so capturing and using the methane is very sustainable.  It benefits the planet because the methane gas is not released into the atmosphere.  And it benefits the profit and bottom line because less energy has to be purchased to operate the facility.

 The Madison-Chatham Joint Sewage Treatment Plant is undergoing a $3 million upgrade, which will include improvements to the digesters.  The digesters, which handle hundreds of thousands of gallons of waste at a time, are going to be cleaned and a new mixing system designed to increase the production of methane gas will be installed.  Because the upgrade will make the facility more energy self-sufficient, it's designated as a "green" project.

The first phase of the project, demolishing and filling in a 100 year old digester that was abandoned 50 years ago, is nearly complete.

                      digester
Sewage Treatment Plant Superintendent Chris Manak shows off one of the digesters that is receiving a major upgrade which will help recapture more methane from the plant.

For more information on the plant upgrade, please visit a recent article on-line at http://madison.injersey.com/2010/05/17/molitor-mad-chat-joint-upgrade/

 Visit the following wikipedia page to learn more about anaerobic digestion... http://en.wikipedia.org/wiki/Anaerobic_digestion