Alcoa Pilots New Technology to Reduce Industrial Emissions at Fraction of the Cost of Conventional Equipment with Less Environmental Impact

June 03, 2013


Alcoa Technology Uses 50 Percent Less Water and 30 Percent Less Energy than Traditional Scrubber Equipment; Demonstration Project a First Step to Commercialization


Lake Charles, LA and Pittsburgh, June 3, 2013 – Alcoa (NYSE:AA) has launched a breakthrough technology to reduce emissions at industrial facilities at a fraction of the cost of current, state-of-the-art “scrubber” technology. Alcoa’s In-Duct Scrubber, under construction as part of a commercial-scale demonstration project at the company’s baked anode and calcined coke facility in Lake Charles, Louisiana, will remove up to 90 percent of sulfur dioxide, particulate matter and hydrogen fluoride emissions at the plant. Commissioning and on-site testing of the project is expected to be complete in August 2014.


Compared to traditional wet scrubbers originally developed to reduce emissions at power plants and large industrial facilities, Alcoa’s patented technology has the ability to dramatically reduce scrubber installation costs and reduce operating costs by approximately one-third for aluminum smelters and refineries, primarily due to improved processes and increased energy efficiencies. It uses 50 percent less water, consumes 30 percent less energy and is more compact.


“Alcoa’s experts have extended the boundary of traditional scrubbing equipment, enabling a more cost-effective, robust and sustainable alternative for reducing industrial emissions,” said Ray Kilmer, Alcoa’s Executive Vice President and Chief Technology Officer. “Following successful completion of this pilot, we plan to commercialize our technology to help other companies reduce emissions at a fraction of the cost of using conventional scrubbers, making it a bankable technology.”


Conventional scrubbers, suitable primarily for large power plants, are 100- to 150-foot tall towers requiring significant capital to construct and energy to operate. These traditional systems pump a limestone or sodium-based solution to the top of the tower and spray the solution onto flue gas, which is propelled from the bottom to the top of the building. This process uses 50 percent more water and 30 percent more energy than Alcoa’s technology.


Alcoa’s In-Duct Scrubber was designed to reduce sulfur dioxide and particulate matter emissions generated from aluminum smelters as well as small to intermediate industrial boilers ranging from 50- to 120-megawatts. The scrubber moves flue gas from the smelter or boiler into a horizontal chamber and sprays a sodium-based solution onto the gas stream in the same direction as the gas flow. The sodium-based solution reacts with the sulfur dioxide in the flue gas to turn it into water and sodium sulfate.  When mixed with lime, sodium sulfate produces a gypsum byproduct which can be used to make various beneficial products such as wallboard and additives for cement making.


Alcoa’s high-velocity, horizontal scrubbing process allows up to three times more gas to be treated than in an equivalent conventional scrubber space and requires 30 percent less energy to operate.  The technology treats upwards of 90 percent of sulfur dioxide in less than one-fifth of a second compared to traditional wet scrubbers, which could take 10-15 seconds. The technology also is modular in design and requires less physical space allowing flexibility in how these systems are constructed.


Alcoa’s experts at the Alcoa Technical Center, the world’s largest light metals research and development center based outside of Pittsburgh, PA, developed the In-Duct Scrubber technology in collaboration with Alcoa’s Global Primary Products group. The Alcoa Technical Center is Alcoa’s largest research, development, and applied engineering laboratory with a highly skilled workforce holding more than 100 doctorate and 200 master’s Degrees.


Alcoa’s Lake Charles plant makes baked carbon anodes and calcined coke for use in smelting operations. The plant has an annual production capacity of 283,000 metric tons of calcined coke and 138,000 metric tons of carbon anodes, and employs 182 people. The In-Duct Scrubber pilot project will create 40 construction jobs over the next 12 months.


About Alcoa

Alcoa is the world’s leading producer of primary and fabricated aluminum, as well as the world’s largest miner of bauxite and refiner of alumina. In addition to inventing the modern-day aluminum industry, Alcoa innovation has been behind major milestones in the aerospace, automotive, packaging, building and construction, commercial transportation, consumer electronics and industrial markets over the past 125 years. Among the solutions Alcoa markets are flat-rolled products, hard alloy extrusions, and forgings, as well as Alcoa® wheels, fastening systems, precision and investment castings, and building systems in addition to its expertise in other light metals such as titanium and nickel-based super alloys. Sustainability is an integral part of Alcoa’s operating practices and the product design and engineering it provides to customers. Alcoa has been a member of the Dow Jones Sustainability Index for 11 consecutive years and approximately 75 percent of all of the aluminum ever produced since 1888 is still in active use today. Alcoa employs approximately 61,000 people in 30 countries across the world. For more information, visit and follow @Alcoa on Twitter at and follow Alcoa on Facebook at