What is the “Zeta potential”

Why is calcium carbonate (a filler) only used in alkaline papermaking processes?

When recycled fiber entered the paper making scene paper makers were not very excited about it. In some cases they had to slow down the paper machine and/or use more energy to dry the paper…. why do you think recycled fiber is more difficult to dry?

Complete the table below by filling in either increased or decreased to indicate the effect of multiple recycling on the indicated paper/paper machine qualities. Tensile strength a. Burst strength b. Fiber length c. Fines content d. Speed of drainage of paper machine e. Fiber stiffness f.

As you recycle paper microbial contamination can be an issue. Generally that is not something recycled paper mills worry about. How do you think it is addressed? ( think about how you can kill microbes)

Describe how the following paper properties change during beating/refining.  tensile strength density of sheet tear strength drainage of water during paper formation Explain why the properties change in this way. That is, why does tensile strength increase or decrease? What changes are made to the pulp that result in the paper properties changes?

Describe a forward cleaner. Be sure to address the following questions.  Where is the pulp inlet? Separation is accomplished based on what principles? Where do rejects and accepts exit?

What thickening device would you use if you wanted to get your pulp consistency from 1 percent up to around 4 to 8 percent?

Why is it that you generally have a washing stage after every bleaching stage? Do you normally send the bleach plant effluent to chemical recovery section? If not why not? Where do you send the bleach plant effluent then?

Sort the following chemicals into the three given categories. Some chemicals might belong in two different categories. Categories:Lignin removing chemicalsLignin retaining chemicalsReducing agentsChemicals to sort:sodium hydrosulfitechlorineFASchlorine dioxideozoneoxygenhypochloritehydrogen peroxide