NICE³ Projects Reach Successful Conclusion

In 1993 and again in 1994, projects sponsored by P²AD were selected for funding under the National Industrial Competitiveness through Energy, Environment, and Economics (NICE³) program. NICE³ is a U.S. Department of Energy (DOE), Office of Industrial Technology (OIT) cost-sharing grant program. It is designed to enhance the economic competitiveness of U.S. industry by promoting energy efficiency and clean production. Funding is provided to state and industry partnerships for the development and commercial deployment of innovative technologies which use less energy and generate less waste.

Carpet Industry

The first of these projects demonstrated an improved process for the batch dyeing of nylon carpet. Through the work of the Georgia Tech Research Institute and the School of Textile and Fiber Engineering, a prototype dyebath reuse system was developed, installed, and successfully operated at Shaw Industries, Plant No. 2 in Dalton, Georgia. Funding support was also provided by P²AD, Georgia Research Alliance, and Dalton Utilities.

Dyeing is a fundamental process in carpet and textile manufacturing. It is a process requiring the use of significant quantities of water, chemicals, and energy. Scientific investigations have shown that these materials can be reused rather than discarded after each batch of fiber or fabric is dyed. Carpet and textile manufacturers have expressed strong interest in dyebath reuse if an automated system could be developed.

A team of Georgia Tech textile chemists, engineers, and computer scientists working in conjunction with technical specialists at Shaw spent approximately 36 months in the laboratory and plant developing, installing, and testing the prototype system. According to Dr. James L. Clark, who served as project director, "these trials have shown that an automated system can successfully analyze concentrations of ...spent dyebaths without operator assistance and that dyebaths can be reconstituted and reused without compromising the quality of the carpet produced."

In the normal batch dyeing process carpet, dye, and auxiliary chemicals are placed in a process vessel containing heated water, called a beck. Once the dyeing is completed, all of the water, the energy used to heat it, and residual chemicals are poured down the drain. Recapturing, reconstituting, and reusing spent dyebath has substantial benefits - energy efficiency, water conservation, waste reduction, and pollution prevention.

Data generated by the in-plant trials at Shaw indicated that the technology can reduce the cost of carpet dyeing by approximately three cents per pound. The actual savings for any one plant will depend on scheduling and the percentage of total production employing the technology. However, since the average commercial dyehouse may process as much as 50 million pounds of carpet per year, significant savings can be realized by the use of this technology.

Pulp & Paper Industry

The pulp and paper industry ranks third in energy consumption among all U.S. industries. A significant portion of the energy used by the industry is devoted to recovering chemicals that can be recycled in the wood pulping process. In 1994, DOE awarded a grant for the development of a new process for the recovery of lime in pulp and paper manufacturing. The process, called Advanced Mineral Calciner (AMC), was developed by Altex Technologies Corporation. Initial plans called for a subsequent demonstration of the technology at the Weyerhaeuser plant in Oglethorpe, Georgia. The project is a collaborative effort involving Altex, DOE, P²AD, Weyerhauser, J.C. Steele, Inc. (extrusion equipment manufacturer), and Svedala Industries (kiln manufacturer).

Lime is a primary ingredient in the paper making process. Spent lime, in the form of lime mud, can be regenerated and reused by heating it to very high temperatures, a process known as "calcining". Once recovered, the lime can be reused in the pulp making process. Plants that do not regenerate their lime must landfill their waste lime and purchase fresh lime. Industry wide, approximately two million tons of spent lime mud are sent to the landfill each year.

The conventional lime regeneration system involves the use of a rotary kiln to convert lime mud into fresh lime. In the AMC process, lime mud is formed into pellets which are dropped into a vertical kiln where they are dried and calcined. AMC technology has many advantages that should make it attractive to the industry. It produces lower emissions than a rotary kiln. It is lower in capital and operating costs. Since the vertical kiln can be insulated, it has the potential for substantial energy savings over a rotary kiln. Also, AMC requires significantly less floor space than the standard horizontal rotary kilns. Moreover, the technology can be applied to other industries where lime is used such as sugar production, soda ash manufacturing, and waste water treatment.

With the funding and technical support provided by DOE through the NICE³ program and the successful demonstration of these technologies, a new phase in P²AD's applied research effort begins. In echoing the goal of all of the organizations that participated in these projects, Dr. Clark stated "we don't want this to simply be a technical report that sits on a library shelf ...we will make every effort to promote the widespread implementation of this technology." These technology transfer efforts will include commercialization of the prototype system and dissemination of information and project data through videos, journal articles, fact-sheets, industry-specific seminars, and conference presentations.

For more information on the automated dyebath reuse project contact Dr. James L. Clark, Georgia Tech Research Institute, Georgia Institute of Technology, Atlanta, Georgia 30332, (404) 894-6103; for information on the Advanced Mineral Calciner, contact Mr. Medhi Namazian, Altex Technologies Corporation, 650 Nuttman Road, Suite 114, Santa Clara, California 95054, (408) 982-2300.

--Greg Andrews