Rinsing cleaning equipment process steps

The second category of water is non-compendial. Non-compendial water, often referred to as potable water, is generally used for initial rinsing and cleaning of process rooms and equipment. This water should meet the Public Health Services Drinking Water Standards.Non-compendial water is also used in the laboratory environment and is usually referred to by the final treatment step, e.g., reverse osmosis (RO) water and deionized (DI) water. 

Process water—The water used in BPC production is usually deionized water through the early process stages. If the product is isolated from a water solution in its last step, then a compendial grade of water, purified water or WFI may be utilized depending upon subsequent steps in dosage manufacture and the final use of the product. Cleaning of equipment can be performed with city water, provided the last rinse of the equipment is with the same water utilized in the process step. The validation of water systems has been well documented in the literature (15,16). 

Water rinses are used in surface preparation operations such as acid pickling, alkaline cleaning, and nickel deposition to remove any process solution film left from the previous bath. A water rinse may also follow the neutralization step. Another common water use is in the ball milling process, which uses water as the vehicle for the enamel ingredients, as a cooling medium, and for cleaning the equipment. Coating application processes normally use wet spray booths to capture oversprayed enamel particles. Water wash spray booths use a water curtain into which the enamel particles are blown and captured. 

Membrane cleaning involves the removal of a substance that is not an integral part of the membrane material [176]. The process must remove fouling deposits and must restore the normal capacity and separation characteristics of the equipment [175]. The cleaning process is usually divided into two main steps rinsing and chemical cleaning. 

Chemical cleaning sequences are often contained in conveyorized spray equipment with rinsing between each step. Batch processing in a tank system is also used, with a hoist for basket movement between solutions. Uniformity of the etching of panels within a basket must be measured, but is generally quite good and reproducible as long as the immersion time is short and the bath s chemical composition is consistent. 

---