Chlorine Bleach Wood Pulp

Pulp and paper industry currently uses chlorine dioxide bleaching also known as elemental chlorine free or ecf.

Chlorine bleach wood pulp.

It does not use elemental chlorine gas during the bleaching process and prevents the formation of dioxins and dioxin like compounds carcinogens. Chlorine dioxide ecf technology currently is the most important bleaching method worldwide. In the production of paper residual lignin from wood pulp is chemically liberated by using chlorine bleaching forming chlorinated lignin derivates such as chlorolignols. Read on to find out what each one does and how to use them safely.

Although preliminary surveys have detected dioxin in pulp mill wastes the scope of the problem is not yet known. Elemental chlorine free ecf. These are toxic carcinogenic and recalcitrant to degradation. Biobleaching is an important alternative to reduce the use of chlorine.

Elemental chlorine free ecf is a technique that uses chlorine dioxide for the bleaching of wood pulp. For over four decades we have helped the industry navigate the changing landscape of bleaching technologies. Ecf is a pollution prevention technology recognized and accepted globally by such organizations as the united nations environment. The use of chlorine dioxide minimizes the amount of organochlorine compounds produced.

According to an industry group the use of chlorine dioxide in these processes has reduced the dioxin generation to under detectable levels. Traditionally the paper industry used chlorine gas to bleach pulp. Bleaching is done to whiten the paper which makes text on it easier to read the chlorine produces several by products including dioxins and furans. Ecf bleaching is the worldwide bleaching standard despite tcf being 100 chlorine free.

Bleaching wood subtract color to add life. In this process the wood pulp s color is enlightened and whiten. Recently paper makers have begun using chlorine dioxide to bleach paper. About 95 of all bleached kraft pulp is made using chlorine dioxide in ecf bleaching sequences.

It has been found that bleaching can result in the formation of dioxin in the pulp when chlorine reacts with organic constituents of wood. As a core component of best available technique bat for production of pulp paper and board ecf bleaching will likely continue to dominate. For example the use of elemental chlorine in the bleaching of wood pulp produces organochlorines and persistent organic pollutants including dioxins. Two part bleach changes the actual color of wood and the other three remove stains.

Chlorine dioxide serves as a bleaching agent for wood pulp and it is used because chlorine dioxide minimizes the amount of organochlorine compound that are produced in the process. Chlorine is commonly used as a bleach. It is used at moderately acidic ph 3 5 to 6.