| 摘要 |
<p>A method of papermaking having zero liquid discharge. A pulp slurry (1) is produced from recycled cellulosic material and the slurry contains suspended cellulosic fiber material, solid contaminants and dissolved water soluble solids. The pulp slurry (1) is subjected to a cleaning operation (3) to produce a first flow stream containing the cellulosic fiber material and dissolved solids and a second flow stream containing dissolved solids along with solid contaminants. The first flow stream is washed (8) with water to remove a substantial portion of the dissolved solids and provide a washed pulp which is used in a papermaking machine (9) to produce a paper sheet. The second flow stream from the cleaning operation (3) is compacted to produce a solid residue that can be landfilled and a liquid residue containing dissolved solids that can be recycled to the pulp cleaning operation (3). In a modified form of the invention, the liquid residue from the compaction can be subjected to a process, such as evaporation (6), to provide a solid residue and a purified water or condensate which can be used in the papermaking machine (9).</p> |
