A Guide to Safe and Effective Tank Cleaning

More documents

Recommendations

Info

Step 1 Select the right tank cleaning nozzle Evaluating these factors will help you select the best automated tank cleaning nozzle to meet your cleaning objectives. Assess the residue to be cleaned Is the substance sticky or easily cleaned Can it be dissolved by the cleaning liquid What is the level of impact required to dissolve it and wash it away Determine the level of cleaning required Rinsing: Majority of residue is loosened and removed with water Cleaning: Remaining residue is loosened and removed with water and cleaning agent High Impact Cleaning: Utilizes the impact of the spray to break apart difficult and stubborn residues and wash them away Sanitizing: Chemical agent is applied to all surfaces to kill micro-organisms to an acceptable level Disinfecting: Kills most bacteria with the exception of spores Sterilizing: Eliminates all forms of life Identify your cleaning solution and the required temperature of the cleaning liquid Chemical additives are typically used to remove contaminants, improve tank wettability and reduce droplet formation. Heat can improve the cleaning action of many water-based detergent chemicals. Evaluate the size of your tank and the spray distance Spray distance is usually measured in terms of the tank diameter, however, it is important to consider the tank length and height. For example, if a tank is 20 ft. (6 m) in diameter and 40 ft. (12 m) long, use two tank washers that specify 20 ft. (6 m) or a single tank washer that can clean up to 40 ft (12 m). Determine the lowest possible flow rate required to achieve your cleaning objectives The lower the flow, the less liquid required, less effluent for disposal and less energy consumed. A general guideline is to work with a minimum of 0.2 gal/min/ft 2 (7 l/min/m 2 ). A more moderate recommendation is 0.4 gal/min/ft 2 (15 l/min/m 2 ). This guideline generally applies to stationary nozzles where all the surfaces of the tank are sprayed at the same time. Nozzles that rotate usually contact part of the tank at one time, thus less flow rate is needed. Determine the level of spray impact required Hard-to-clean residues require a higher level of impact than residues that are easily rinsed. It is difficult to determine the exact impact value of each tank wash nozzle. However, a general rule of thumb can help you increase the level of impact when determining the optimum cleaning requirements for your application. Increasing flow rate is more effective than increasing pressure. As the chart below shows, doubling the flow rate increases impact as much as 100%, while doubling pressure provides only 40% more impact. Flow Rate Pressure Relative Impact 13 gpm (50 l/min) 45 psi (3 bar) 1.0 13 gpm (50 l/min) 90 psi (6 bar) 1.4 26 gpm (100 l/min) 45 psi (3 bar) 2.0 Impact values are based on theoretical total impact formula: Impact = .0526 x flow rate x √pressure 6 1.800.95.SPRAY | Intl. 1.630.665.5000 | www.spray.com
Identify the best spray pattern for your level of cleaning Solid stream sprays provide the greatest impact, followed by flat fan and full cone sprays. Typically, fixed spray nozzles with full cone sprays are used for gentle rinsing and washing. Fluid driven nozzles with flat fan sprays offer more impact and are commonly used for cleaning. High-pressure, motor driven and turbine driven nozzles use solid streams for maximum impact. Evaluate your tank design to identify spray coverage and obstructions Cleaning coverage provided by various spray angles ranges from 65 to 360 degrees. Multiple nozzles may be required if a spray cannot reach a part of the tank due to internal obstructions such as a mixer or agitator. Types of Tank Cleaning Nozzles High-pressure (motor driven) Two to four nozzles rotate on a motor driven gear hub • Solid stream, high impact nozzles clean stubborn residue • High impact reduces the water required for effective cleaning • Lightweight, portable • Recommended for cleaning medium to large tanks • Liquid pressure and rotational speeds are independently controlled Fluid driven (reactionary force) Rotational velocity increases as pressure increases • Good impact and coverage, less fluid consumption • Wide variety of materials available • Sanitary design features • Recommended for rinsing and cleaning small tanks Fluid driven (constant speed) Rotates at constant speed as pressure fluctuates • Slow rotational speed improves impact and throw Determine the duration of the cleaning cycle Most cleaning cycles last from 10 to 30 minutes and include three to four stages: pre-rinse, which should remove 90% of the soil; cleaning; post-rinse and sanitizing. • Low liquid consumption • Recommended for cleaning and sanitizing small tanks Select a nozzle material and connection type appropriate for your application For most applications, stainless steel nozzles are used for their durability and ability to withstand high temperatures. For corrosive applications, nozzles made of polytetrafluoroethylene (PTFE) or polyvinylidene fluoride (PVDF) are preferred. For sanitary applications, standards may require special consideration for nozzle design, mounting specifications and materials of construction. Fixed (stationary) Multiple orifice assemblies stay in position while spraying • Simple design, no moving parts • Wide range of spray coverage • No mounting limitations • Recommended for rinsing small tanks 1.800.95.SPRAY | Intl. 1.630.665.5000 | www.spray.com 7
Page 1 and 2: Spray Nozzles Spray Control Spray A
Page 3 and 4: Min. Tank Opening Size Inlet Connec
Page 5: Evaluate your current tank cleaning
Page 9 and 10: Step 3 Integrate all system compone
Page 11 and 12: Motor Driven Tank Washers 80' (24.4
Page 21 and 22: Motor Driven Tank Washers 8' (2.4 m
Page 23 and 24: Fluid Driven Reactionary Force 25'
Page 25 and 26: Fluid Driven Reactionary Force 18'
Page 27 and 28: Fluid Driven Reactionary Force 8' (
Page 35 and 36: Fluid Driven Constant Speed 20' (6.
Page 37 and 38: Fluid Driven Constant Speed 12' (3.
Page 39 and 40: Fixed Tank Washing Nozzles 22' (6.7
Page 45 and 46: Fixed Tank Washing Nozzles 3' (.9 m
Page 47 and 48: AutoJet ® Tank Cleaning Systems Au
Page 49 and 50: Strainers and Mesh Information Stra
Page 51 and 52: Celcon ® is a registered trademark
Page 53: Company____________________________

A Guide to Safe and Effective Tank Cleaning

Create successful ePaper yourself

Delete template?

Save as template?