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JohnsonDiversey CIP Cleaning in place • The circulation of non foaming cleaners

JohnsonDiversey CIP Cleaning in place • The circulation of non foaming cleaners without dismantling the equipment. • An automatic and systematic cleaning of the inner surfaces of tanks, heat exchangers, pumps, valves and pipes. JohnsonDiversey CIP properties • Strong and hot solutions can be used. The heat, the chemistry and the mechanics can be sustained long. • The solutions can be reused. • Can be automated and reproducibility is good. • Investment in equipment is high. • The mechanics are not always sufficient JohnsonDiversey JohnsonDiversey Flow Rate vs. Flow Velocity ∏ = . . 3600 . 4 2 d Q v Where, v = flow velocity meters per second Q = flow rate m3 per hour π = pi (3.1415,…) dimensionless d = inside pipe diameter meters second 1 second per volume diameter inside JohnsonDiversey Velocity vs flow 1.5 m/s velocity 2.0 m/s velocity Pipe size ID mm Litres / sec Litres / sec DN 50 47 2.6 3.5 DN 80 77 6.9 9.3 DN 100 97 11.1 14.8 DN150 147 25.5 33.9 JohnsonDiversey Vertical vessel flow requirements - sprayballs Vertical vessels For most vessels, the sprayball delivers a uniform quantity of solution to the upper circumference of the vessel Based on soil level, deliver a given quantity of solution to a unit length of circumference - called liquid loading: Don’t forget about flow OUT of vessels JohnsonDiversey Sprayball Placement       Θ ⋅ + = 2 - 180 tan D Height Dome Sprayball of Depth Where, θ = angle of coverage, degrees D = diameter of vessel, meters Dome height meters NOTE: This is valid for simple vessels without obstructions. Additional sprayballs may be required. Depth of Sprayball Dome Weld Sprayball Dome Height 140º JohnsonDiversey example 15’ 100 gpm 6” dia. JohnsonDiversey Sprayball pressure Sprayball pressure is critical Generally in the range (1.0) 1.5 - 2.5 (3.0) bar Too little pressure and the vessel walls are not reached Too much and the spray atomises reducing mechanical action Larger sprayballs with larger hole diameters can operate at higher pressures without atomising. All sprayballs have specified flow / pressure curves JohnsonDiversey JohnsonDiversey Vertical vessel flow requirements - sprayballs Flow as a function of diameter and soil QR = required flow rate liters per minute DT = vessel diameter meters p = pi (3.1415,…) dimensionless FS = soil factor liters/(meter-minute) FS = 27 for light soil conditions FS = 30 for medium soil conditions FS = 32 for heavy soil conditions S F T D R Q ⋅ ⋅ = π JohnsonDiversey JohnsonDiversey JohnsonDiversey High pressure rotary sprayheads Add impingement to the mechanical action Generally consume a little less water Have specific times to wet surfaces and impinge on them dependent on pressure and gearing Not very effective on larger vessels under 5 bar pressure Use similar data to specify as sprayballs Use manufacturers recommendations Toftejorg have a computer simulation program called TRAX - use it JohnsonDiversey CIP Optimizing CIP optimizing is the process of minimizing the cost inputs of CIP cleaning water effluent energy chemical electrical heat CO2 production time JohnsonDiversey Optimizing drivers CIP system design clean circuits - no dead legs, no flow splits accurate and non competing instrumentation - conductivity monitoring no leaks CIP program correct CIP program philosophy CIP preparation sequence - correct conductivity starting point tidy CIP fluids interface management - always in lines never in tanks correct valve sequencing on monitor signals defined terminators each CIP step JohnsonDiversey CIP optimizing - circuit volume To predict CIP losses and costs we must know the CIP circuit volume. This has nothing to do with the size of the CIP tanks. It is the amount of liquid held up in the CIP headers and the vessel or line being cleaned. To calculate the circuit volume for a line clean we need to know the diameters of the lines and the length of each line size. To calculate the circuit volume of a vessel clean we need to know the line information and the dimensions of the vessel being cleaned. If there is other processing plant in the CIP circuit, we need to know it’s volume too. JohnsonDiversey Vessel Hold-up Volume Assume a 2 millimeter film thickness (0.002 m) Assume a completely wetted surface Determine internal surface area Dome Cylinder Cone Dome Cylinder Cone JohnsonDiversey Vessel Hold-up Volume Area of Dome: Area of Cylinder: Area of Cone h2 h1 D 2 Dome Area r π = 2 Cylinder Area h D π = ( )2 1 2 1 2 4 Cone Area h D D + = π D r 2 1 : NOTE = JohnsonDiversey CIP optimizing - chemical loss management Liquid loss for an efficient vessel CIP system is about 10% of circuit volume. Line cleans can be run more efficiently than vessel cleans - as low as 5% loss. Effective loss management depends on: Effective Flow meter or conductivity interface detection. Managing liquid interfaces into pipes not vessels. When managing liquid changes in vessels the program must be stepped. New liquid to sprayball chasing old liquid into vessel. Over scavenge old liquid from vessel into return line. New liquid into vessel chasing old along return line to interface detector. First step should be volumetric and set for each vessel. JohnsonDiversey CIP optimizing - chemical loss management measured as % of concentrate detergent lost compared to the concentrate detergent in the CIP circuit volume concentrate detergent lost is calculated by CIP tank, volume and concentration, before and after CIP concentrate detergent in circuit volume calculated as the volume of solution held in the CIP circuit excluding the CIP tank at the starting concentration JohnsonDiversey The CIP flow is best circulated bypassing the CIP tanks with the heating and chemical dosing in line uploads/Litterature/ cip.pdf