The pulp and paper industry is a highly energy-intensive industry in Japan consuming huge amount of energy next to steel and cement industries.
One of the major challenges facing our industry is to raise the self-supplying ratio of its energy consumption, which can be achieved, among others, by utilizing paper sludge effectively as fuel after dewatering it to higher dryness.
Starting from August, 1982, the Ashigara plant of Meiji Seika Kaisha, Ltd. succeeded in dewatering the sludge generated in the plant (e. g. from the activated sludge process waste water treatment facilities) to a high dryness, and burning it in a multiple hearth incinerator without the aid of fuel oil.... contributing greatly to the reduction in energy consumption.
The intensive dewatering system of sludge employed by the plant features in (i) pelletizing the sludge from the primary dewatering stage, and (ii) mixing the pellets with the furnace ash, product of the preceding cycle, and (iii) squeezing them by a hydraulic press.
It is a noteworthy technique in that it has achieved a dryness level that was considered economically prohibitive.
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