Turning Waste Into Resource | Green Energy News

October 10, 2009 – Vol.14 No.29

TURNING WASTE INTO RESOURCE.
by Bruce Mulliken, Green Energy News

Shame on us. We consume so much. We gobble up natural resources at an alarming rate with little concern that those resources will never be replaced.

Our trash, our waste, takes up precious and expensive space. Our communities all to often have to buy land just to fill it up with our throwaways.

Slowly (very slowly) we’re getting better at dealing with our junk. Recycling programs do their best to collect valuable materials like aluminum and glass and put it back in the production chain: old cans and bottles become new cans and bottles. While the bulk of our trash may be thrown in a hole in the ground to be covered with dirt, slowly, project-by-project, the methane gases created by the rotting of our garbage is being captured and used as fuel to generate electricity in landfill gas operations. At least our trash is useful when it’s used to make energy.

Some of our trash is burnt too creating a new source of energy and a renewable one at that. (There will always be a steady flow of trash.) But, conventional waste-to-energy projects have emissions that are not really clean thus those projects are not exactly the darlings of environmentalists.

I don’t expect our consumptive economy to go away anytime soon. But eventually we could get very sophisticated, and clean, in coping with our waste. Surely recycling efforts will continue. The value of the recycled goods, particularly metals, will ensure that these programs will go on. Further, in a more high-tech version of a waste-to-energy plant the bulk of our waste could be tapped as a new cleaner source of energy. Trash, known professionally as Municipal Solid Waste (MSW), might in a decade or two be regularly turned to fuel or directly into electricity at local, community facilities eliminating the need for landfill dumps.

The technology to do that is emerging today.

As reported in September 2009 in this publication, Envion of Washington, DC has developed and is now testing at a Maryland waste transfer station its Envion Oil Generator that converts waste plastic to light and medium synthetic oil. The process will convert all types of plastic (no need to separate types: throw it all in) and will convert one ton of plastic into approximately four, 42-gallon barrels of oil. The oil is a refined and 99 percent sediment free product that can be used to produce gasoline, diesel fuel, jet fuel and kerosene. Envion’s proprietary process converts plastic into oil through low temperature thermal cracking in a vacuum (a type of pyrolysis) and doesn’t require the combustion of fossil fuels.

(A simple definition of pyrolysis is the chemical decomposition of condensed organic substances (like plastics) by heating.)

Envion describes its technology Waste to Resource, a good choice of words.

True, this particular technology converts only waste plastic to useful fuel, but plastic takes up nearly 24 percent of the capacity of our nation’s landfills. And, plastic left in the ground doesn’t decay, so not only is there, like forever, but it won’t even provide a source of energy, or have any other use, while buried in the dirt.

Envion has one sophisticated waste-to-resource product, QinetiQ of the U.K. has another in the pipeline. The company has entered into a $2.38 million, three-year Indefinite Delivery Indefinite Quantity (IDIQ) contract to develop and deliver PyTEC(TM) – a containerized Pyrolysis Waste Disposal System – to the U.S. Army.

PyTEC unit will be able to operate 24/7 and process up to 220 lbs (100kg) of MSW per hour converting the waste to enough thermal energy to sustain the process with some energy left over to generate spare electricity. That electricity can be used for any purpose at an army base. Overall the PyTEC will produce 500 kW of the thermal energy from the waste per hour.

The unit will be housed in two standard free standing interconnected 8 ft x 8 ft x 20 ft skeleton containers. It will convert any type of MSW including all general domestic waste that might be produced in an army base such as food, medical and sanitary waste, paper, plastics, tin, oil and glass.

PyTEC will require minimal operator training and allow unsorted waste to be continually fed into automated the closed loop pyrolysis system. The waste from the unit itself is about 7 gallons of inert “char” produced for every 220 lbs of raw waste processed. The amount of char can vary depending on the composition of the waste inputs.

The PyTEC will create an opportunity for an army base to dispose of waste while it also helps the base reduce the amount of fuel needed to generate power.

"PyTEC reduces the need for outside contractors to access the secure base camp to dispose of solid waste, dramatically reducing potential threats," added Pat McGlead, QinetiQ's Business Development Manager for the PyTEC solution. "Not having to rely on local contractors for solid waste disposal gives commanders the flexibility to operate in terrain which would be otherwise unsupportable plus means they can proactively manage their environmental impact. The energy recovery aspect will also significantly reduce the amount of fuel needed to support the base camp and provide associated cost savings while reducing the number of trucks on the road and freeing logistics assets for more critical mission requirements. PyTEC will enable the US Army forward operating bases to move towards being more self sufficient in the management of their waste management requirements."

Though the unit is small, and designed to be transported, it seems obvious that the technology could be scaled-up to handle community-sized waste disposal.

The U.S. military has long history as being a “proving ground” for technologies that eventually end up in the private sector. Who knows 10, 20 years from now the trash that we toss away at the curb might be only hours away from providing energy for our homes or vehicles. When that happens we’ll be putting our waste to work and our waste will be a resource. At that time we’ll be ending the practice of sweeping our trash under the rug by hiding it underground.

QinetiQ is an international provider of technology-based services and solutions to the defense, security and related markets.

Links:

Envion
http://www.envion.com

QinetiQ
http://www.QinetiQ.com

--- Envion Introduces Plastic Waste to Oil Converter.