Plasma arc is favored as a means to destroy medical and hazardous waste. Plasma processing of waste is an ecologically clean process. The lack of oxygen and high temperature in a reactor prevent the main elements of gas from forming toxic compounds, such as furans, dioxins, NOX, or sulfur dioxide. Extensive filtration removes inorganic residue (ash) and gaseous pollutants (NO, HCl, H2S, etc) and allows the production of ecologically clean synthetic gas. The gaseous compounds do not contain any phenols or complex hydrocarbons. The circulating water in these filtering systems has removed the hazardous substances and must be cleaned.
As fully as I want to swoon ecstatic for the current realization of such boundless human ingenuity, we are not quite there yet. The question is of course will Plasma gasification be allowed to flourish with tremendous backing?
Nowhere in the article about the 700-acre Columbia Ridge Landfill in Arlington, Oregon, talk about the price point. In another Wired piece from 2006, has its own price...
The $425 million facility expected to be built in St. Lucie County, Florida. Using a 100,000-square-foot plant, slated to be operational in two years, is expected to vaporize 3,000 tons of garbage a day. County officials estimate their entire landfill -- 4.3 million tons of trash collected since 1978 -- will be gone in 18 years.
"We've found projects similar to this being misrepresented all over the country," said Monica Wilson of the Global Alliance for Incinerator Alternatives. She also said other companies have tried to produce such results and failed. She cited two similar facilities run by different companies in Australia and Germany that closed after failing to meet emissions standards.
Americans generated 236 million tons of garbage in 2003, about 4.5 pounds per person, per day, according to the latest figures from the EPA. Roughly 130 million tons went to landfills -- enough to cover a football field 703 miles high with garbage. … if large plasma facilities were put to use nationwide to vaporize trash, they could theoretically generate electricity equivalent to about 25 nuclear power plants.
But in a more recent article about Microwave Gasification, the St. Lucie facility is mentioned but at a third of the cost...
"To kick this technology off in the region, Geoplasma, part of real estate developer Jacoby Group, has secured a permit from Florida's Department of Environmental Protection to build the St. Lucie Plasma Gasification Facility in St. Lucie County, worth an investment of $140-150 million. The facility is set to produce 24 MW (gross) of power from nearly 600 tonnes of waste and tyres per day.
Speaking to Waste Management World magazine (WMW), Geoplasma president Hilburn Hillestad says the firm intends to break ground on the project in January 2012, with an 18-month construction period meaning the project will be ready by mid 2013. Technology will be provided by Westinghouse Plasma Corporation, subsidiary of Alter NRG.
But, with claims that microwave plasma gasification is 60% more efficient than existing processes, and the ability to produce 70% diesel as a by-product; the ABA process really could be game-changer on the WtE landscape."
So even at the substantially cheaper cost using Microwaves, the hundreds of Million$ price tag will probably not see even 50 facilities, one for each state any time soon.
Were this future waste tech actually to blanket this consumption machine called a nation, I see further uses of the technology could include fitting all Plasma Gas facilites with an Algae snorkel to harvest any Carbon Dioxide emissions, also later coupled with burning the "fabled Clean Coal". (The whole Mining Industry seems ripe for robots; this filthy work should have precedence before Warehouses.)
That said even though there is a short list of concerns, that slightly dulls the glimmer of such wondrous science.
- Requires large electrical energy input if the waste stream does not contains a large fraction of unoxidized hydrocarbons;
- The highly corrosive plasma flame may lead to frequent maintenance and component replacement with associated facility down time;
- The filters and gas treatment systems are themselves sources of toxic waste, some of which (e.g. acidified water) are poor candidates for plasma processing.
Others would let ignorance and apathy take hold, mumbling that dumping garbage into the earth is cheaper. This is elucidated well over at Earthanet.
"Landfills charge municipalities an average of $35 per ton of trash; according to a recent study in Hamilton, Ont., dropping off a ton of garbage at a plasma gasification plant would run $172 per ton …Burying garbage in the ground is primitive technology with numerous harmful effects that aren’t taken into consideration when figuring cost per ton. No matter how miraculous the liner material in today’s modern landfills, they all eventually leak and dump a nasty toxic stew into the groundwater below."
And the scale it could work on. Ideally one "Mr. Reactor" in every town with electrically or liquid syngas powered Garbage Trucks to service an area. A Hybrid world should see our civilization a longer distance with a cleaner conscience. I think Neal Stephenson (judging by his 2011 essay) would heartily agree, that humans must get Back on track to the Future.