Methods for cleaning industrial equipment with pre-treatment

Abstract

A method of cleaning equipment such as heat exchangers, evaporators, tanks and other industrial equipment using clean-in-place procedures and a pre-treatment solution prior to the conventional CIP cleaning process. The pre-treatment step improves the degree of softening of the soil, and thus facilitates its removal. The pre-treatment solution can be a strong acidic solution, a strong alkaline solution, or comprise a penetrant. A preferred strong acidic solution is an acid peroxide solution. In some embodiments, the pre-treatment may include no strong alkali or acid ingredient; rather, the penetrant provides acceptable levels of pre-treatment.

Description

CROSS REFERENCE TO RELATED APPLICATION [0001] This application is a continuation-in-part of U.S. patent application Ser. No. 10 / 928,774 titled METHODS FOR CLEANING INDUSTRIAL EQUIPMENT WITH PRE-TREATMENT, filed on Aug. 27, 2004, the complete disclosure of which is incorporated herein by reference in its entirety.FIELD [0002] The invention relates to cleaning of industrial equipment such as evaporators, heat exchangers and other such equipment that is conventionally cleaned using a CIP (clean-in-place) process. BACKGROUND [0003] In many industrial applications, such as the manufacture of foods and beverages, hard surfaces commonly become contaminated with soils such as carbohydrate, proteinaceous, and hardness soils, food oil soils and other soils. Such soils can arise from the manufacture of both liquid and solid foodstuffs. Carbohydrate soils, such as cellulosics, monosaccharides, disaccharides, oligosaccharides, starches, gums and other complex materials, when dried, can form toug...

AI Technical Summary

Benefits of technology

[0014] In another aspect, the invention is directed to a method that includes pre-treating the soiled surfaces with a strong alkaline solution. A conventional clean-in-place process follows this pre-treatment step. It has been found that a conventional clean-in-place process using an acidic detergent after the strong alkaline pre-treatment step provides particularly effective results.

[0015] Either of the pre-treatments, either acidic or alkaline, may include a penetrant. The addition of a penetrant improves the degree of softening of the soil, and thus facilitates the removal of the soil. The concentration of penetrant in a pre-treatment solution is at least 0.01 and usually at least 0.15%. A concentration of about 1% is acceptable.

Problems solved by technology

In many industrial applications, such as the manufacture of foods and beverages, hard surfaces commonly become contaminated with soils such as carbohydrate, proteinaceous, and hardness soils, food oil soils and other soils.

The removal of such carbohydrate soils can be a significant problem.

Food and beverage soils are particularly tenacious when they are heated during processing.

All of the evaporation plant equipment should be cleaned, however, the actual evaporator typically has the most difficult soiling problems.

When that surface is a heat exchange surface, the soil becomes thermally degraded rendering it even more difficult to remove.

The layer of soil acts as an insulator between the heat and the product being heated, thereby reducing the efficiency of the heat exchange surface and requiring more energy to create the same effect if the heat exchange surface were clean.

When the heat exchange surface is an evaporator, the difference between a clean heat exchange surface and a soiled heat exchange surface can mean the difference in millions of dollars in energy costs for an evaporator plant.

Clean-in-place processing requires a complete or partial shutdown of the equipment being cleaned, which results in lost production time.

Many times, the equipment is not thoroughly cleaned, due to the large downtime needed.

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