Clearly, Komax Systems, Inc. mixers are found across the spectrum of industry, from municipal waste treatment to the oil sands of Alberta. So it comes as no surprise to find their mixers and heaters in the vast pulp industry where they have helped paper plants become more efficient.
Paper Plants
Geographically, pulp plants are found in locations boasting a plentiful water supply and a source of cellulose. Cellulose, of course, being the vascular fibers found in the higher forms of plant life (i.e., gymnosperms and angiosperms). Among the woods used, softer ones, such as spruce, pine, fir, and larch, are the preferred species in North America,where paper manufacturers use scrub growth rather than disturbing the older, larger trees.
Initially, wood chips, old paper, and straw are chopped into smaller pieces and compressed to remove the latent water remaining in the fibers, leaving cellulose and lignin in the mix. Lignin is the “glue” that holds the plant fibers together and its removal becomes the next step in the process. After screening away the detritus, dissolved sodium salts, called white liquor, are mixed and subsequently “cooked” under pressure. This stage, called impregnation, also involves air entrainment and heat.
Steam Recovery
As a sideline step, the “stream” goes through a recovery step to reclaim the white liquor, while the rosins are skimmed from the pulp in evaporating vats. Old dyes and other extraneous materials are also removed at this time. The next stage is called blowing, in which the pulp stream is driven through mixers and filters in the presencesof high temperature stream.
Final stages include anywhere from 3-5 more washings, and depending on the need, bleaching or coloring. Also along the way, surfactants to reduce surface tension, emulsifiers, and other materials are needed to produce the quality of paper desired.