Professionals in pharmaceutical and food and beverage plants that use clean-in-place (CIP) systems may realize the key to efficient, cost-effective CIP is effective use of conductivity measurement. Conductivity measurement makes it possible to assure that cleaning fluid is thoroughly removed from the tanks, pumps, valves, filters, heat exchangers and process piping of the system without contaminating the process or wasting materials. But even though conductivity measurement is a time-honored and straightforward method of measurement, using it effectively in CIP is challenging. This interesting new white paper gives you some tips and techniques for optimizing CIP operations.
The requirements of the CIP process can be complex, and the nature of conductivity measurement makes it the ideal analytical technique for CIP, but there are several common challenges that users encounter. The caustic and harsh nature of the environment in which the conductivity sensor must work means the sensor used has to be highly robust in order to withstand the heat and chemicals of the process. At the same time, the sensor must be appropriate for use in food or pharmaceutical manufacturing applications.
An even greater challenge is the need for sensor rangeability since the process involves two distinctly different conductivity measurement ranges – one for moderate-to-high concentrations of acid and caustic, and the other for the purified rinse water. Therefore, any conductivity sensor used must be highly sensitive and accurate over the high conductivity range of CIP.
When evaluating conductivity sensors for this application, two types come under consideration: contacting and inductive. Only one type is appropriate for the demands of CIP and that is inductive or toroidal conductivity. The design of contacting conductivity sensors places their measurement electrodes into direct contact with the solution to be measured, which can foul or corrode the electrodes in the corrosive CIP environment. The smooth, crevice-free surface of toroidal sensors, on the other hand, protects the electrodes from the process, so these sensors seldom require cleaning and do not collect or harbor residue or trap microorganisms. As a result, coating and plugging are virtually eliminated and the toroidal sensor can be made sanitary by design. Advanced toroidal sensors, such as the Rosemount 225 PUR-Sense toroidal conductivity sensor from Emerson, offer exceptional rangeability to accommodate the requirements of CIP. At the same time, contacting conductivity sensors provide one distinct advantage over toroidal – they enable a rapid response time at lower, near pure water conductivities. Therefore, an optimal CIP measurement system will incorporate the contacting conductivity sensor, as well as the toroidal sensor, since the contacting sensor enables a fast response to the conductivity change between the clean and rinse cycles, enhancing the performance of the CIP system. Quick response time saves high-purity rinse water, which reduces costs and is better for the environment.
To learn more about how to choose and use your conductivity sensors for optimum efficiency and cost-effectiveness, check out the white paper.