This summer a series of trials is underway at Cape Girardeau cement manufacturer Buzzi Unicem in an effort to use more hazardous waste as fuel. The company invested $1 million in the project aimed at cutting its operating expenses by burning more waste in its kiln instead of coal.
For about 20 years, the company, formerly known as Lonestar Industries, has used hazardous waste -- things like waste paint, ink, oil and solvents -- as fuel to heat its kiln.
Previously, the company burned hazardous waste in one of two combustion chambers in its kiln. The other used coal.
In June, its hazardous waste permit was modified by the Environmental Protection Agency and the Missouri Department of Natural Resources to allow it to burn the same waste fuel materials in the second chamber of its kiln, called a calciner.
The company does not burn materials such as pesticides, poisons, radioactive materials or polychlorinated biphenyls, known as PCBs.
Tankers unload an average of 5,000 gallons of waste solvents at Buzzi Unicem USA. The cement manufacturing plant can burn 12 truckloads a day in its kiln.
(Fred Lynch)
"This offsets our use of coal approximately pound for pound, thus conserving fossil fuels and safely disposing of waste materials from other industries," said Paul Schell, environmental engineer at Buzzi Unicem. The hazardous waste is burned to produce heat for the cement manufacturing process. The raw materials of cement must be heated to about 2,700 degrees for the chemical reactions that change it into clinker, the intermediate product that is ground to make Portland cement.
Cutting fuel costs has been increasingly important in recent years, as the construction industry has slumped due to the economic downturn forcing many cement plants in the United States to shut down or idle due to lack of demand for cement, Schell said.
Buzzi must buy its coal, but companies pay Buzzi to dispose of their hazardous waste.
"There are savings and revenue generated from the use of the hazardous waste," Schell said.
"The Cape Girardeau plant has been able to continue operating throughout this time without any layoffs in part due to the lower production costs associated with the use of hazardous waste fuel," he said. The company has 172 employees, including 24 at its alternative fuels facility.
Buzzi began burning hazardous waste in its calciner June 21 and conducted stack testing the weeks of July 9 and July 16.
Stack tests the week of July 9 showed that the burning of hazardous waste in the calciner does not increase emissions of sulfur dioxide, nitrogen oxides, carbon monoxide or total hydrocarbons when compared to coal.
The sulfur dioxide and nitrogen oxide emissions "decreased significantly when coal was replaced with hazardous waste fuel," Schell said.
Additional stack testing was done the week of July 16 for hazardous air pollutants including dioxins, lead, mercury, chromium and chlorine. Currently, hazardous waste is not being burned in the calciner as the company awaits the results of those tests, Schell said.
Tests this week, however, did demonstrate that more than 99.99 percent of two difficult-to-destroy chlorinated solvents were destroyed when burned in the calciner.
"By doing so, we can be assured that the other hazardous liquids that burn more easily will be destroyed in an equal or greater degree," Schell said.
Testing showed that the company can safely burn 250 pounds per minute of hazardous waste fuel in its calciner, Schell said. That's in addition to the 420 pounds per minute the company is already permitted to burn in its kiln.
The use of hazardous waste fuels is regulated by the Clean Air Act and stricter regulations have led some companies to quit using it.
In the EPA's Region 7, which covers Iowa, Kansas, Missouri and Nebraska, there used to be seven companies burning hazardous waste, but now there are only four, said Benjamin Washburn, EPA public affairs specialist.
"Since EPA established regulations for burning hazardous waste in boilers and industrial furnaces, the trend has been for fewer companies to burn hazardous waste," Washburn said.
In Missouri, Green America Recycling in Hannibal and its parent company, Continental Cement, have a similar but not identical hazardous waste burning operation, said Renee Bungart, spokeswoman for the Missouri Department of Natural Resources.
Currently all of Buzzi's hazardous waste fuel is delivered by truck from off-site manufacturers or third-party hazardous waste blenders, Schell said. The company is looking into making additional investments to allow it to receive bulk material by rail, he said.
On Friday, the Southeast Missouri Regional Planning Commission will present Buzzi with a plaque in recognition of its contributions to the organization's Clean Air Action Plan.
