The effects of steam and NaOH steam, in comparison with water and sodium hydroxide, on the swelling behavior and removal forces of three food-based soils were investigated. Comparative cleaning experiments were performed using these food soils after pre-swelling with NaOH steam, steam, NaOH, or water. The cleaning progress, cleaning rates, and efficiency parameters were then determined.

Abstract

In conventional cleaning-in-place (CIP) processes, only a small fraction of cleaning fluids directly contacts soil layers, limiting their effectiveness. Alternatively, steam can be incorporated into CIP procedures, offering advantages such as prolonged contact time, reduced chemical and water consumption, and enhanced wetting of spray shadow areas. This study specifically investigates the effect of steam during the swelling phase of soil layers. Experiments were conducted using steam, NaOH steam, water, and NaOH solution, respectively. Steam demonstrated an over 100 times higher swelling efficiency compared to liquids. Cleaning studies demonstrated that the use of steam achieved similar cleaning times to water-swollen soil layers, while NaOH resulted in shorter times, with steam being twice as resource-efficient.