SD&C Technical phosphates as energy savers in machine dishwash performance

Abstract

A savings of 20% in the energy consumption of machine dishwashers to meet government guidelines requires a significant reduction in the amount of water used or in the temperature of the wash. Performance testing has shown that a reduction in wash temperature from 140 F to 100 F results in a significant increase in the spotting and filming of glassware. This performance loss to conserve energy can be reduced by increasing the sodium tripolyphosphate (STP) content of the machine dishwash formulation. A reduction in the STP content of the formulation from the typical 40-45% level that would be required to comply with restrictive phosphate (8.7% P) legislation coupled with a decrease in wash temperature for energy conservation results in extremely poor washing performance.