Ciders have been growing in popularity over the past few years. South Africa has experienced robust year-on-year growth in volume terms. Consumers in South Africa have become more discerning and demanding of cider.
With the variety of imports available to the South African consumer, Food and Beverage manufacturers have now added pressure to produce their products in an even more competitive way than before, and at the same time responding to consumers’ desires for new and appetising products, which are also environmentally friendly. The primary concern of any design engineer is to gain increased production and consistent product quality by employing the benefits of effective process automation.
High-Tech Processing (Pty) Ltd is a breweries, beverages, alcoholic and soft drink plants solutions provider and consultant. They offer comprehensive, integrated engineering solutions to Food and Beverage manufacturers, while consistently meeting production quality standards.
Well renowned for their work with the big names in alcohol and beverage production, such as SAB, Distell and Coco-Cola. High-Tech Processing was recently involved in a huge plant expansion for an international beverage manufacturer here in South Africa. Together with Endress+Hauser, they were able to prime integration capabilities between products, system solutions and services to create a more efficient, cost saving operation for the customer.
With almost 50 vessels to engineer and commission, this was no small task for High-Tech Processing’s lead E&I Engineer, Reinhardt Grobler. When asked what their main challenges were, which they encountered during the project, Reinhardt said; “In building a beverage process plant, one of the engineer’s primary objectives is to gain increased production and consistent product quality by employing the benefits of effective process automation. The key in meeting this objective is by selecting suitable instrumentation which is capable of producing an accurate and repeatable indication of the process status. This may seem like an obvious statement, but with an overwhelming choice of techniques and wide variety of designs, on what basis does the engineer select the “ideal” instruments?”
Well known as the leaders in instrumentation in the Food and Beverage Industry, Endress+Hauser was able to provide expert advice on reliable, quality measurements that would supply the necessary data for the ideal process. The application involved the measurement of volume in 15m high tanks containing 2200 hl of cider. The tanks were equipped with an agitator and the product would often form thick layers of foam. The Deltapilot (FMB70) was selected for level measurement in the tanks. It is not affected by foam and is perfectly adapted to fast changing process conditions. The patented hermetically sealed CONTITE measuring cell is condensate and climate resistant. The sensor shows best performance and long-term stability and accuracy even following CIP/SIP cycles. Hydrostatic level transmitters are probably the simplest to use and apply. A sensor converts the pressure of liquid head acting on a process diaphragm into an electrical signal. When the density of the liquid is known, this signal is a direct indication of the level. Hydrostatic level transmitters are the most commonly used level measurement in the Food and Beverage Industry.
However, when the customer decided to use the tanks for a variety of different products: With a change in product characteristics, the calculated volume was affected by the changes in density. To overcome the challenge of the changing densities, and to gain more accuracy of the volume measurements, a density computer was used. In conjunction with the tuning fork, Liquiphant M, the density computer FML621 returns a continuous measured density value. The volume of the tank can now easily be calculated since the density and hydrostatic pressure is known.
The new volume calculation, with the corrected density, now resulted in a +-1.5% inaccuracy of the total volume of 2200hl. There was a decrease in lost production time since production was also able to optimise their packaging process to plan better due the more accurate volume measurement. With the changes in density previously affecting the calculated volumes, packaging could not plan efficiently. The number of bottles to be packaged did not correspond to the volumes in the tank. As a result the line would have to stop and wait for more bottles so that the tanks could be emptied out or on counter side, bottles remaining empty on the line with the tank running empty earlier than expected.
Profibus DP was selected as the communication protocol. Reinhardt preferred the use of digital communication which simplified commissioning and helped ensure efficient operation. “Profibus allowed more information to be available to optimise the process, for example; the density sensor was also used to detect the low level in the tank as well as measure the changing density. It also ensured that possible losses over an analogue line is eliminated and thus resulted in a more accurate data value transfer between the Density Computer and the PLC. With intelligent communication, information can be used to monitor instrument diagnostics and therefore ensure optimum performance”.
With a satisfied end customer and a project well done, the only thing left to do was to repeat the solution. High-Tech Processing already has plans to use the system on a new project involving the volume measurement in 20 new tanks.