DESIGN PARAMETERS FOR OPERATION OF A STEAM INJECTION HEATER WITHOUT WATER HAMMER WHEN PROCESSING VISCOUS FOOD PRODUCTS

Steam injection heating systems for food and agricultural products are subject to condensation–induced water hammer (CWH), which may cause significant damage to equipment and pose a threat to operators. A method is suggested for process design and operation of a steam injection heater that reduces occurrence of CWH. The method is based on a correlation between the thermodynamic ratio of the product and the Peclet number. A laboratory steam injection heater was instrumented to determine the relationship between CWH, the thermodynamic ratio, and the Peclet number. The thermodynamic ratio for water and various concentrations (55 to 67.5 brix) of sucrose solution was recorded under process conditions at the onset of CWH during steam injection heating. Good correlation was observed between the Peclet number and threshold thermodynamic ratio. A linear equation was found (with r2 = 0.79) that gives the predicted minimum thermodynamic ratio for system operation without CWH.