Cost Savings With an Effective Chemicals Mixing System at Mitsubishi Paper Hachinohe Mill PM7

摘要

During this time of increasing costs of raw materials and energies, Mitsubishi Paper Mills Ltd., Hachinohe mill, Aomori, Japan, has been realizing extensive cost reductions by 'optimization of wet-end process' on No.7 paper machine (PM7) since spring of 2005.After introducing the new chemical mixing system, TrumpJet~?, developed by Wetend Technologies Ltd in Finland, on the PM7 in 2006, the chemical mixing was greatly improved and the total consumption of retention aid polymers was reduced by 35% less. The lifetime of wires and felts was extended as a result of the improvement of total first pass retention (FPR) and ash retention.The Technology: Jet injection mixing system for wet end additives exploits the headbox feed stock for injection liquid, eliminating the need of fresh water for chemical dosage. The flash mixing takes place quickly and thoroughly. Additive savings and improvements in sheet quality can be significant. Elimination of the water results in considerable savings of energy and reduction of CO_2 emission due to the fact there is not any more need to heat up the eliminated water to the process temperature. Total annual savings by the Jet injection mixing installations world wide is more than 33 million cubic meters of fresh water with 1.5 million MWh energy saving with about 1 milj CO_2 emission reduction potential.