Date of Defense
Date of Graduation
Chemical and Paper Engineering
The objective of this design report is to find the impact of replacing an existing barrier coating that is applied offsite with a poly-free one administered on the machine for 8000 tons of paper per year. The location of application was chosen to be the wet and dry stack. This will also reduce shipping costs, as current board is sent to Canada for the current coating before being sent back to New York. The goal of this design is to remove this freight cost, as well as use a more sustainable barrier coating.
An analysis of this coating was conducted to compare it to starch that is commonly used in water boxes. It was found that this coating has pseudoplastic, or shear thinning, properties compared to thixotropic properties in the starch. This material is also much more viscous compared to starch. When heated, this coating will solidify. With this in mind, a makedown system was designed to create batches of coating that are sent to a tank that handles the coating sent to the water boxes. This makedown tank will be smaller than the tanks at each water box. These water boxes must be cooled to keep the temperature of the coating down. Due to the non-corrosive and low temperature nature of the coating, equipment can be made of carbon steel and pipes do not need be made of a higher schedule number. The major savings comes from the reduction in price from the coating and the freight costs from not shipping it to Canada.
This process results in a highly profitable situation due to the cost reductions per MSF. The internal rate of return is 95.53% and the payback period is 0.9 years based on economic analysis. Additional profit can be made by using a sprayer system instead of water boxes. This wouldn’t need a second stage for coating and does not require cooling water. Proper selection of spray nozzle, distance between sprayers, and nozzle pressure would need to be researched.
Siegfried, Andrew, "Application of New Coating to Replace Poly Liner" (2023). Honors Theses. 3640.