Method for minimizing pulp mill effluents
    2.
    发明授权
    Method for minimizing pulp mill effluents 失效
    减少纸浆厂废水的方法

    公开(公告)号:US5374333A

    公开(公告)日:1994-12-20

    申请号:US922334

    申请日:1992-07-30

    IPC分类号: D21C9/10 D21C11/00 D21C11/12

    CPC分类号: D21C11/0021 Y10S162/08

    摘要: Apparatus for a pulp and paper mill, and methods of acting on liquid effluents produced in the mill, which minimizes the discharge of polluting gaseous and liquid effluents to the environment. Liquid effluents from the bleach plant are concentrated (e.g. evaporated), incinerated (e.g. gasified), leached, crystallized (e.g. freeze crystallized) then washed, and then fed to the plant chemical recovery loop. White liquor produced from the recovery boiler melt is fully oxidized and used in place of caustic in the bleach plant. Essentially all sulfuric acid, sulfur dioxide, caustic, and chlorine dioxide necessary for the pulp mill is produced from mill liquid effluents and gas waste streams, on site at the pulp mill. Typical bleaching sequences that can be used are DE.sub.op D.sub.n D, or AZE.sub.o PZP.

    摘要翻译: 用于纸浆和造纸厂的设备,以及作用于在磨机中产生的液体流出物上的方法,其最大限度地减少污染的气态和液体流出物排放到环境中。 来自漂白设备的液体流出物被浓缩(例如蒸发),焚化(例如气化),沥滤,结晶(例如冷冻结晶),然后洗涤,然后进料至植物化学回收循环。 从回收锅炉熔体产生的白液被完全氧化并用于漂白设备中的苛性碱。 纸浆厂所必需的硫酸,二氧化硫,苛性碱和二氧化氯基本上都是从磨浆液流出物和废气流中产生的。 可以使用的典型漂白序列是DEopDnD或AZEoPZP。

    Method of managing liquid steams in a pulp mill
    6.
    发明授权
    Method of managing liquid steams in a pulp mill 失效
    在纸浆厂中管理液体蒸汽的方法

    公开(公告)号:US5302246A

    公开(公告)日:1994-04-12

    申请号:US25386

    申请日:1993-03-02

    摘要: In minimizing effluents from a cellulose pulp mill, liquid effluents from a bleach plant are concentrated, and then incinerated to produce a residue including sodium, sulfate, and sodium chloride. This residue is distilled with sulfuric acid to produce gaseous hydrogen chloride and remaining residue, the HCl being used in chloride dioxide production for the bleach plant, while the remaining residue is passed to the recovery loop (e.g. recovery boiler). Sulfur containing gases from the non-condensible gas system may be combusted to produce gaseous sulfur dioxide, which is then converted to sulfuric acid, to distill the residue. Where a non-chlorine bleach plant is provided, the liquid effluents may be concentrated in evaporators and then passed directly to the recovery boiler. The liquid streams in the mill are managed by a cascade principle to reserve the cleanest water for only those processes where it is needed while minimizing its use where it is not necessary.

    摘要翻译: 在使来自纤维素纸浆厂的流出物最小化的同时,将来自漂白设备的液体流出物浓缩,然后焚化以产生包括钠,硫酸盐和氯化钠的残余物。 该残余物用硫酸蒸馏以产生气态氯化氢和剩余残余物,HCl用于漂白设备的二氧化氯生产中,而剩余的残余物通过回收回路(例如回收锅炉)。 来自不可冷凝气体系统的含硫气体可以燃烧以产生气态二氧化硫,然后将其转化为硫酸以蒸馏残余物。 当提供非氯漂白设备时,液体流出物可以浓缩在蒸发器中,然后直接通入回收锅炉。 磨机中的液体流是通过级联原理进行管理的,以便在需要的地方只为那些需要处理的过程保留最干净的水,同时尽可能减少不必要的使用。