Low Cost Capital Approach to Environmental Pressures: The Super O2 Process, 1996 International Pulp Bleaching Conference Proceedings

In response to proposed new environmental regulations in Canada and the U.S., aimed at decreasing levels of environmental parameters released through mill effluents, many mills are actively modifying their processes to reduce the formation of pollutants. In most cases, this is being done at a great capital cost to the company. Until recently, the industry has reacted to environmental regulations by installing end-of-pipe treatment systems and add-on controls. The Super O2 process offers an opportunity to achieve equivalent results at a fraction of the capital cost of these methods. The process includes oxygen delignification, lignin activation and oxygen bleaching technologies as well as a yield enhancement polysulphide cooking process, all of which make use of O2 . The process has minimal capital cost because it utilizes and re-deploys existing mill equipment. Additionally, it can be retrofitted into a five (or more) stage bleach plant anywhere in the world. The development of new on-site oxygen production technologies, such as VPSA, represents another potential cost saving for the new process. On site production eliminates the considerable costs associated with liquid oxygen delivery to the mill. VPSA systems have been installed at a number of mills worldwide, and have been found to be quite suitable for oxygen delignification. Operating gains from this process come in the form of improved wood yield and the elimination of the need to upgrade the ClO2 manufacturing facilities. The primary environmental benefits are substantially lower effluent parameters and the compatibility with the “Closed Mill Concept”. Financially, the process delivers lower capital expenditure with an attractive ROI.