Gasify Garbage On-Site to Make Electricity

Image via Ecoworld

Converting municipal waste / garbage to syngas and electricity is preferable in many ways to landfills and simple combustion disposal. But collecting the garbage and shipping it to a central gasification plant costs time and money. Why not gasify the waste on-site, then use CHP to maximise efficiencies? Preferably using combined cycle turbine electrical generation. Ecoworld took a look at one such on-site gasifier by IST Energy.

...campuses, military bases, hospitals, and other institutions or commercial complexes can install a waste-to-energy solution from IST Energy, available in modules so it can be scaled to whatever waste processing requirement may apply.

During an interview last week with Stu Haber, CEO of IST Energy, he said the unit they are developing is 30′ by 8.5′ by 8′ high, able to fit in a standard shipping container for intermodal delivery anywhere. Into this volume, the system IST Energy has designed includes space for 3 tons of MSW storage at the front end (so it only has to be fed once per day), with a shredder, dryer, pelletizer, zero-emission gasifier, and internal combustion engine electricity generator that runs on the syngas extracted from the MSW.

...IST Energy intends to sell these units for about $850,000 each, meaning for that price you could process about 1,100 tons of waste each year, generating about 1.3 million kilowatt-hours, along with co-gen heat. At $.15 per kilowatt-hour, you would recover $200K per year just in electricity, plus you would harvest the heat, and presumably, save money on garbage collection fees (only about 5% of the volume of the waste material input remains as ash). If IST Energy can deliver this unit in large quantities according to these specifications, they have a very disruptive technology. _Ecoworld

IST will market this technology to "campuses, military bases, hospitals, and other institutions or commercial complexes". A similar system has been in use at a US base in Iraq since summer of 2008. These systems are relatively small, and shippable via standard shipping container.

But for the big garbage producers -- cities and towns -- a larger facility located at the garbage disposal site should incorporate IGCC technology for CHP production. Pretreatment is key to efficient gasification, and the jury is still out in regard to optimal pre-treatment for municipal waste. Stay tuned.