Hennepin Energy Recovery Center (HERC) Improvements = Cleaner Air

Via an October 14 Hennepin County News Release:

Hennepin Energy Recovery Center improvements aim to cut smog-causing nitrogen oxides by 25%

Hennepin County is installing new pollution control equipment at the Hennepin Energy Recovery Center (HERC) that will reduce emissions of nitrogen oxides (NOx) by about 25 percent. NOx contributes to the formation of ground-level ozone, commonly known as smog. Smog can aggravate asthma and other respiratory conditions.

The new equipment injects a urea solution, a non-toxic chemical, into the boilers to reduce NOx levels. This technology has been proven effective and efficient at other waste-to-energy facilities. The estimated cost is $1.5 million and was approved by the county board Tuesday. The cost of the new system to reduce NOx will be paid out of the Solid Waste Enterprise Fund, which comes from tipping fees paid by waste haulers delivering garbage to HERC.

In Hennepin County, 38,000 tons of NOx are released annually. About 80 percent of it comes from the exhaust of transportation sources; only 1.5 percent comes from waste incineration at HERC. The total amount of NOx released into the atmosphere in Minnesota annually has decreased by nearly 20 percent in the past decade. The county has contributed to the reduction of NOx by improving energy efficiency in county buildings and in its fleet, and by promoting public transportation and bicycle use.

Hennepin County residents and businesses generate more than one million tons of waste each year. Processing waste for energy at HERC is just one part of the county’s integrated waste management system that emphasizes waste prevention, reuse, recycling and composting. About 45 percent of the waste generated in the county is recycled or composted. The remaining trash can either be buried in the ground or burned for energy.

HERC has fewer environmental impacts than landfills. It is located where the trash is generated, minimizing the NOx and other air pollution from the transportation of waste to landfills. HERC captures more energy from waste than landfills, which reduces the use of fossil fuels. Waste in landfills continues to decompose, producing methane and organic compounds. 

The county is making progress toward the goal of zero waste and waste generation per capita is decreasing as recycling rates are increasing. It is committed to making recycling convenient and expanding opportunities to compost. It offers grants, educational materials and professional staff assistance to improve recycling at businesses, schools, apartment buildings, events and public spaces.