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Wood Chip quality is very important for pulp quality for both mechanical and chemical pulping. Some chip variables include: bark content, extractive (pitch) content, uniform thickness, chip age, rotten wood content, sand content. a) Please pick one variable you think is the most important for mechanical pulping and one variable that is the most important for chemical pulping and explain why you picked this one and how you would try to control it. b) From a mass transfer perspective what are some of the basic  mechanisms that play a role during Kraft pulping of wood chips.  

Paper made from mechanical pulp generally has a lower tensile strength than paper made from chemical pulps. Please explain why that is, I am looking for at least two reasons. What kind of paper grade or paper product (give one example) are mechanical pulps most suited for?     

Please describe the operation of a wet electrostatic precipitator? What function does the water have in these systems? 

Why can an aerated lagoon be designed to be 25 or more feet deep, while a natural lagoon cannot be deeper than 3 or 4 feet?

Define the terms BOD5 and COD. Indicate what they measure and explain in general terms how the tests are performed.

More and more companies are considering the use of bio filters for water treatment. What are biofilters, how do they work? 

What are the main sources of water pollution in a pulp and paper mill.. please name at least 4

Describe the function of the primary effluent treatment. List two typical types of equipment that are used for primary treatment.

Complete the following equation. (1 point) organic material + oxygen –> ____ + ____

What are the advantages and disadvantages of activated sludge treatment compared to an aerated lagoon?