PDA CIP Components
PDA Mini-CIP System Test Tank and Spray Device
The Test Tank used with the Mini-CIP Skid at PDA was a gift of a small cone bottom tank with a 1″ outlet. The only modifications to date has been the fabrication of a Plexiglass cover with an O-Ring groove located to cause the seal to the vessel to (hioefukk) occur at the small radius near the inner edge. The Riboflavin Spray Coverage demonstration done duing the first twelve years (approximately 60 courses , each done two times for two small groups) has suggested a suitable location, for seldom has any Riboflavin been observed beyond the O-Ring, unless it was sprayed there before the CIP demonstration. The Test Tank is vented via a 2″ double 90 degree elbow, modified since this photo was taken to include a 1″ Dip-Tube used only for the CIP Validation Course program.
The Spray device is 1-3/4″ OD, drilled 12 Gpm top coverage. All streams hit on the flat surface but the horizontal component of the streams velocity carries the water to the tank wall in this small tank. The spray supply tube is clamped into a 2″ PVC nozzle which simply slips snugly into a 2″ hole in the center of the Plexiglass lid. The spray ball is attached to the tube with a 1″ slip-joint and a retainer clip, in a manner similar to that used for thousands of ESC fixed ball-type sprays in commercial use in the Biopharm industry. This spray ball however is not directionally drilled.
PDA Mini-CIP System Vortex Breaker
When the first course was taught in 1999 no prior effort had been made to operate the original manually controlled demo system The test tank was filled to a depth of four inches and the two ball-type valves were repositioned to establish recirculation through the spray. Recycle immediately stopped due to pump air-binding. Two additional 4″ increments of water were required to enable recycle in this small vessel with a 1″ outlet. A vortex nearly 12″ in depth was formed when water was pulled from the tank at only 12 Gpm. And, for the first course, recycle occurred with the fixed spray ball submerged about 1-1/2″ – 2″ below the water surface, so the first two groups of students observe spray coverage only during the Rinse part of the demonstration. This was subsequently corrected by ESC fabrication of a Flat Plate Vortex Breaker, 4″ in diameter, positioned in the 1″ outlet by four fins which centered the plate 1/2″ above the cone bottom. This is not an acceptable method of dealing with this problem in ASME dish bottom tanks with EP finish, but it does demonstrate to the Aseptic Processing Course students how forcing side entry to the outlet orifice, in an area much greater than the areas of the 1″ nozzle, therefore at a far lesser velocity, will enable recycle with about 4″ of water over the plate. This height is required for static head to enable recycle at the 15 Gpm flow rate required for 12 Gpm through the spray and 3 Gpm through the 1″ Flexline and Filter housing cleaned in parallel with the vessel for the CIP demonstration.
Effective spray cleaning and vortex control are closely related and both need to be fully understood. Additional information on Tank CIP Vortex Control can be found in the CUSTOM SPRAY DEVICE section of this web site.