A research consortium has developed a technology to produce low-cost, high-quality zeolites using paper sludge which has been disposed of as industrial waste, and started manufacturing sludge-based zeolites at its pilot plant in Ehime Prefecture in June 2004. The consortium consists of businesses, universities and local government entities in Shizuoka and Ehime prefectures, the two largest paper-manufacturing areas in Japan. The research and development of the technology was conducted in fiscal 2003 and 2004 as part of the Consortium R&D Projects for Regional Revitalization which were promoted by the government. The results of the zeolite project were reported in May 2005.

Zeolites are crystalline, microporous, inorganic materials that have unique properties of adsorption, catalysis and ion exchange. Because of these properties, zeolites are used in a variety of applications, including adsorption of harmful substances, removal of foul odors, soil improvement and removal of ammonium ions from sewage water and wastewater. There are three types of zeolites: natural zeolites that occur naturally as minerals; synthetic zeolites which are produced industrially; and artificial zeolites that are made from ashes, such as coal ash and paper sludge ash. Artificial zeolites, also called "the third zeolites," have been attracting attention in recent years due to their features of low production costs and use of waste materials.

The total amount of sludge from the paper and pulp industry in Japan is more than four million tons a year, most of which is incinerated or landfilled at a cost of 6,000 to 7,000 yen (about U.S.$55 to 64) per ton. The disposal costs of massive amounts of sludge and the difficulty in securing landfill sites have been a big problem.

With the newly developed technology to constantly produce low-cost and high-quality zeolites from various kinds of paper sludge, the consortium has paved the way for developing a variety of eco-friendly products using artificial zeolites.



Posted: 2005/10/05 09:56:47 AM
Japanese version

TAG Local government , Manufacturing industry , Material reduction , Technology , University/Research institute