Paper making and fiber liberation – Processes and products – Reclamation – salvage or reuse of materials
Patent
1996-05-28
1998-06-09
Czaja, Donald E.
Paper making and fiber liberation
Processes and products
Reclamation, salvage or reuse of materials
162264, 162 55, 162 29, 162 47, 162 60, 162 44, 159 473, D21F 166, D21F 170, D21C 902
Patent
active
057627584
ABSTRACT:
A method of papermaking having zero liquid discharge. A cellulosic pulp composed of recycled materials is initially cleaned to remove contaminants and foreign material, and the clean pulp is then washed to remove dissolved solids and pulping chemicals, and the washed pulp is then utilized in the papermaking process. The contaminants are separated from the liquid residue resulting from the pulp cleaning operation, preferably by floatation clarification, and the effluent from the clarification is evaporated to produce steam or water vapor along with an evaporated residue. The evaporated residue is combined with the suspended solids that were removed from the liquid residue and the combined residue is then subjected to a mechanical dewatering operation to reduce the water content so that the dewatered material can then be either landfilled or incinerated. The condensate from the evaporation can be combined with fresh makeup water and used in the papermaking process. Water recovered from the papermaking process is recycled to the pulp washing operation and water recovered from the pulp washing is recycled to the pulp cleaning and pulping operations, thus resulting in zero liquid discharge from the operation.
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Czaja Donald E.
Fortuna Jose S.
Hoffman Environmental Systems, Inc.
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