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للمهتمين بصناعة الورق

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  1. [1]
    Chem-Eng2009
    Chem-Eng2009 غير متواجد حالياً

    جديد

    تاريخ التسجيل: Dec 2008
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    للمهتمين بصناعة الورق

    السلام عليكم


    كل عام و انتم بخير


    هذه مشاركتي الأولى في هذا المنتدى أتمنى أن تضيف الفائدة لمعلوماتكم، فصناعة الورق تعد إحدى أهم و اكبر الصناعات في العالم و فيما يلي شرح مبسطة لعملية التصنيع أما من أراد الاستزادة فبإمكانه الاطلاع على الروابط المرفقة



    1. Preparing the wood
    Bark is removed from the logs in large, rotating drums and then made into wood chips ready for pulping.


    2. How is the pulp made?
    The pulping process breaks down wood chips into usable fibers and waste products. Mechanical pulping uses a grinding process to separate the fibers and is mainly used for low cost, short life products like newspapers. Chemical pulping ‘cooks’ the chips to separate the fibers and is used mainly for high quality.


    3. Preparing the pulp
    After making the pulp, it is prepared for the paper machine. This involves ensuring the mix of fibers is correct, refining the pulp, mixing in additives like fillers and chemicals and finally cleaning.


    4. Sheet formation
    The pulp slurry (pulp, chemicals and water) is sent on a wire, or most commonly between 2 wires. The fibers are positioned due to the speed difference between the pulp flow and wire(s).


    5. Removing the water
    At the start of the process the pulp slurry is approximately 98% water. The water is removed by three methods: suction, pressure on the paper sheet and heat.


    6. Creating the right surface
    Sizing agent solution (usually starch) is added to the paper on the size press. The paper is sized by roller pressure in the calendaring section size press. This optimizes the printing surface. Sometimes additional treatments are made (off machine), e.g. coating and / or super calendaring.


    7. Making the rolls of paper
    The finished paper is wound into jumbo reels, and then split into smaller customer reels. The individual reels are finished with a protective wrapper for transport and storage.




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  2. [2]
    السدوين
    السدوين غير متواجد حالياً
    عضو فعال
    الصورة الرمزية السدوين


    تاريخ التسجيل: Feb 2008
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