Pre-rinse cycles often utilize recovered ‘water’ from the intermediate rinse stage. This serves two purposes: first, to reduce total water consumption (and effluent generation); and second, to utilize any heat energy and possible residual detergent solution carried into the recovered rinse tank during the rinse recovery stage. It is not uncommon to find heated pre-rinse systems in certain applications, such as cream production, where the hot pre-rinse solution provides a greatly enhanced method of product residue removal. (more…)

This is where the main task of cleaning takes place, resulting in the soil being lifted from the plant surface and held suspended or dissolved in the detergent solution; for the selection of suitable detergents but an important attribute of the detergent should be the ability to prevent any soil from being re-deposited during recirculation. Recirculation timings need to be assessed by experimentation and a degree of experience, with timing generally varying from 15 min up to 1 h, where exceptionally large and complex circuits are being cleaned. Contact times can be reduced by offsetting the potentially reduced cleaning effectiveness with higher temperatures, higher concentrations, or the use of more sophisticated (and expensive) detergent formulations. (more…)