By Diane Silcock
Vessel cleaning is fundamental in a multitude of industries ranging from brewing, chemical processing to food production. An expert in this area specialising in industry-leading spray technology is Monitor Engineering, sole agent in southern Africa for Spraying Systems Co.
MD Grant Orsmond says, “Our experience with tank cleaning is far-ranging. We’ve solved thousands of application problems in dozens of industries. For more than 70 years we’ve been helping breweries, food, beverage, pharmaceutical, paper, chemical, transportation companies, and more, clean tanks faster and more thoroughly. We encourage our customers to tell us about their tank cleaning or washing operations and we provide an optimal solution that saves them water, chemicals and time.”
Thoroughly understanding tank cleaning
Anthony Wood, an expert at Spray Systems Co involved in the development and design of the company’s tank cleaning product line, says, “Most people appreciate the benefits of automated tank cleaning – less cleaning time, reduced chemical and water use and improved worker safety. However, when it comes to comparing equipment options and techniques to optimise performance, a general understanding isn’t enough. You need to dig deeper to ensure you’re using the best equipment available for your operation and getting the best results.
“When evaluating tank cleaning equipment, one important consideration is impact, which is the amount of force the cleaning liquid applies to the tank surface. If we look at the effect that flow rate and pressure have on impact, operating at lower flow rates conserves energy, water and chemicals, while increasing flow rate increases impact at a greater rate than increasing pressure. Doubling flow rate increases impact by as much as 100% while doubling pressure increases impact by just 40%.”
He cautions that purchase decisions on impact alone would not be wise as not all nozzles are equal. Those that produce the same type of pattern, such as a solid stream, will perform differently depending on how they are designed and machined. He says that the difference in nozzle efficiency from different manufacturers can be as high as 20% and therefore recommends looking for nozzles with 98% to 99% efficiency rating. Spray distance is another important factor to take into account as once the recommended distance is exceeded, the impact will be reduced.
Ways to shorten cleaning time
How best to reduce cleaning time, so that tanks can be returned to service, is very much application dependent and considerations are: increasing impact by increasing flow and/or pressure; increasing temperature of the cleaning liquid; adjusting chemical/water concentration; repositioning the tank cleaning equipment in the tank; using multiple tank cleaners instead of a single unit; and use of a more efficient tank cleaner. Striping and clogging are problems that need to be addressed as these can lead to contamination and unnecessary downtime/loss of production time, costly repairs and rebuilds. These problems can be avoided by consulting the experts and dealing with such issues immediately.
Fermenter cleaning time halved
Wood cites a case study where the cleaning time of a fermenter was reduced from 45 minutes to 20 minutes. The tank cleaning nozzle operating at 40 psi (2.8 bar) wasn’t able to provide effective cleaning in one cycle. A second cycle was required, extending the cleaning time and increasing the use of water and chemicals. The solution was a fluid-driven tank cleaner with a two-nozzle hub operating at 90 psi (6.2 bar) which provided thorough cleaning of the fermenter in less than half the time previously required.
“Our experts are on hand to assist customers reduce maintenance time, lower costs, and increase system uptime. We additionally offer customers a valued-added service of a no charge sustainability assessment with our report advising how to save water, chemicals and time by optimising their tank cleaning processes,” concludes Orsmond.
Contact : grant@monitorspray.co.za
Website: www.spray.co.za
