Application of Ultraviolet Treatment for Paper Production - An Engineering Study

Ultraviolet (UV) radiation systems are a common method of inactivating bacteria in municipal water treatment but has not been applied in a paper mill operations. Determining the feasibility of installing such a system is the purpose of this report. Directly treating a starch solution of sufficient concentration proved impossible as the transmittance required was far too low. Water used in the onsite water recycling facility’s cooling towers had a transmittance over 90% and so was very treatable. Lab scale testing with a designed 15 liter laboratory benchtop ultraviolet treatment system showed that UV treatment can reduce the aerobic bacteria count by two fold for up to 24 hour of operation and significantly lower results for 48 and 72 hour of operation. Therefore, UV treatment can be considered a valuable process for the treatment of cooling tower water.