Merrimack County Dept. of Corrections Heats Up

New Central Biomass System Heats Two NH Prisons

The currently occupied Merrimack County prison at right is tied into the new biomass boiler building and the second prison (not seen to left) through a long enclosed corridor that also contains the heat pipes from the boiler.

Froling Energy of Peterborough, New Hampshire, recently completed the installation and commissioning of a biomass boiler system at the Merrimack County Department of Corrections facility in Boscawen, NH. The Merrimack County Complex site has two prison facilities close to each other. One has been continuously active, while the other was vacant for a number of years, in need of updating. The overall project included major renovations to the older jail, as well as a boiler house and enclosed walkways that would connect the two facilities.

The biomass boiler system installed at the prison has a number of innovative features that significantly reduced costs and made the project financially viable. One is a high efficiency boiler. Another is the new biomass fuel it burns. And the site is the first in the United States to employ a new rake-type chip management and storage system.

Viessmann Vitoflex 300-UF PDC / Pellet Boiler with 4.2 million BTU/hr net output. Photos courtesy of Froling Energy.

The Viessmann Vitoflex 300-UF boiler is one of the most efficient, clean burning biomass boilers available anywhere. Viessmann boilers have also proven themselves to be among the most reliable biomass boilers. The model KPT-1250 deployed here has a maximum heat output of 4.268 million BTUs per hour. It is expected to offset over 120,000 gallons of fuel oil each year.

The new fuel, screened semi-dry wood chips, has a number of advantages. Having just 25% moisture content, the fuel burns cleaner in the Viessmann boiler than green chips. Using just a multi-cyclone on the exhaust, the boiler meets all New Hampshire regulations for particulate emissions. Wetter fuel usually requires the installation of an expensive electrostatic precipitator.

The new storage system is a Javo Toploader, an innovative overhead rake-type chip management system that is much less expensive to construct. Live-floor trucks back right into it to drop off loads of chips. The Toploader then gets to work, gradually pulling the chips forward, towards the boiler feed augers. The new storage area’s maximum capacity is 60 tons of screened semi-dry wood chips.

Froling Energy has years of experience with commercial biomass boilers. That experience was demonstrated with this biomass boiler system installation, one of the largest in the company’s history. Froling Energy provided engineering, procurement, and construction services to Johnson Controls Inc. These included general, civil, and building construction services for the boiler house, the connecting hallways and the entire biomass system with heat distribution pipes to the two jail facilities.

This project received a $200,000 RFP Grant from the Renewable Energy Fund of the New Hampshire Public Utilities Commission. Overall funding for the project was provided through a revenue-neutral Energy Performance Contract managed by Johnson Controls.

Froling Energy’s web site is www.frolingenergy.com/

Many Thanks to our Sponsor:

Merrimack County Dept. of Corrections Heats Up posted first on Green Energy Times