Stellar, a Jacksonville-Fla. based design, engineering, construction and mechanical services firm, is now developing modular renewable energy systems that will convert waste to energy.
Instead of traditional waste management and disposal methods, the new systems enable this waste to be converted into energy. The new systems will serve a range of industries, including waste management and wastewater treatment; food and beverage processing; agricultural (dairy, meat, poultry and crop farms); petrochemical, bio-fuel refining, coal mining; and pharmaceutical and bioscience. These industries produce organic waste such as sludge from wastewater treatment plants, animal waste from meat processing facilities, manure and silage from agricultural sites and food waste from food processing plants.
For example, landfill sites generate biogases (mostly consisting of methane) as the waste buried in them undergoes the natural process of anaerobic digestion, or the breakdown of organic material in the absence of oxygen. If this gas is not harvested (through a renewable energy system), it escapes into the atmosphere and can be 20 times more potent and harmful to the environment than carbon dioxide.
Pending U.S. legislation (both federal and state) and international protocols, such as the Kyoto Protocol, will soon dictate more restrictive emission rates and expanded renewable energy requirements for manufacturers and other producers.
To transform waste into energy, the waste must be pre-treated, separated and stored in enclosed tanks (called anaerobic digesters) that decompose and break down organic matter by excluding oxygen (this process is called anaerobic digestion), thus producing a biogas. The biogas is then combusted (burned) in an engine to generate electricity, heating and cooling. The electricity produced through this process can be used by the producer (as well as the heating and cooling), sold to a nearby facility or redistributed to a nearby electrical grid.
In addition to lowering overall energy costs and generating additional income through the sale of the excess electricity or thermal energy produced, these systems support sustainability initiatives, offer alternatives to waste reduction and lower greenhouse gas emissions, said Kurt Liebendorfer, Stellar senior vice president. In addition, they offer an efficient and safe way to destroy pathogens and eliminate odors that can sometimes negatively affect a community.
The new biogas systems are modular instead of building the systems on-site, they are constructed and engineered at Stellars 60,000-square-foot fabrication facility in Jacksonville, Fla., and then transported to the site. Modular products enable greater flexibility, consistent high-quality standards, compressed project schedules and long-term reliability. Stellar offers a range of modular products, including modular chiller plants, which are energy plants that provide cold water for air conditioning.