Air Products already has applied its oxyfuel combustion technology to increase production rates, reduce emissions and raise fuel efficiency at aluminum recyclers: producing the metal requires just 5% of the energy needed for making primary aluminum (Figure 2).
Another project involves the steam methane reforming (SMR) process that currently is responsible for almost all hydrogen production. "Not only are we looking to optimize this process, but also how to produce the gas in non-conventional ways, for example, from domestic sewage or biomass — there's a whole range of potential sources. We do have some pilot units testing these new methods but none as yet can replace SMR for commercial-scale hydrogen production in the short term. However, demand is strong and growing for hydrogen, so work on the pilots is going on."
More Process Developments
Meanwhile Bayer MaterialScience, Pittsburgh, is garnering environmental and productivity gains with its IMPACT technology. Marketed as a greener alternative to conventional polyol production processes, IMPACT has helped the company make dramatic improvements at its Channelview, Texas, plant. These include eliminating 75 million pounds of wastewater and reducing energy consumption by 80%.
The technology combines a new catalyst with an innovative process design. Continuous processing replaces a semi-batch approach that has been the industry standard for 50 years.
The catalyst is more than 10 times as reactive as other catalysts in its class and a thousand times more reactive than conventional catalysts, says Bayer. The novel process leverages a unique catalyst characteristic by which low molecular weight materials react preferentially in a mixture of molecular weights. The combination results in a process with little or no waste. The approach saves energy by eliminating the heat-up cycle of the semi-batch process and energy and waste normally associated with catalyst removal.
"The technology is being considered for implementation worldwide as plants are being upgraded or constructed, increasing the positive effects on the environment, which include energy reductions, carbon-dioxide-equivalents reductions and waste elimination," notes Jack Reese, the company's manager of polyether process development.
Dow Chemical Co., Midland, Mich., also is implementing greener technology worldwide.
"Sustainability and energy efficiency are critical initiatives at Dow," stressed Torsten Kraef, Dow Building and Construction business group vice president in early September. He was commenting on the conversion of its Varennes, Quebec, facility to the company's zero-ozone-depleting, no- volatile-organic-compound foaming agent technology for manufacturing Styrofoam extruded polystyrene foam insulation.
The Varennes' move marks the third conversion for Dow (after Hanging Rock, Ohio, and Dalton, Ga.), and its first in Canada, which, like the U.S., under the Montreal Protocol requires phase out of hydrochlorofluorocarbon 142b before January 1, 2010.
BASF, Ludwigshafen, Germany, sees significant opportunities for greener textile production. In a joint project with leading partners along the textile value chain, the company, using empirical data collected during the actual production process, has calculated the carbon footprints of specific articles. BASF textile auxiliaries and technologies then allowed the partners to cut overall CO2 emissions.