How can we support that the food safety is granted while investment and operational costs remaincompetitive? Right tech solutions whatever project size and automation degree is required, are thestronghold of a portfolio of smart sensors with pointed primary and very useful secondary functions. This article shows how this fits into systems that grow with the user and rising challenges.
CIP cleaning is a must in every automated food plant dealing with liquid food. It is not the most appreciated activity of the plant manager, but mandatory to ensure food safety and product quality. It’s time consuming, requires a lot of energy and water and keeps the plant busy while it should produce. The process itself is described in the quality handbook of the plant, defining the parameters for food safety. We want to show, how we can ensure to match the required definitions without overdoing. It is all about focused technology, doing the job as desired and be scalable to the users need and investment possibilities. The basis for successful cleaning is described by the Sinner’s Circle, defining the parameters that need to be given, before the cleaning time really starts to count. Temperature, to solve the residuals, but also to support the usually combined detergents that have ideal working range. Flow, to create mechanical impact to the residuals and to ensure that the dirt is carried out of the plant. And the concentration of the cleaning agent that need to remain in the desired range to support the mechanical forces. If that parameters are within range, the defined cleaning time starts to run down. The smarter this is controlled, the lower the safety margins need to be applied to the system.
Different requirements and investment levels:
The operational mode of a CIP process differs from plant to plant and the product that needs to be cleaned. The most simple option for a CIP system, is a one tank CIP. The tank is more or less used as a buffer to ensure that the pump is supplied with media. It is a lost cleaning, as all the media is drained after use. A one tank CIP can be operated with very little media. This ensures, that not too much energy is used to heat up cleaning agents. But it also means, that the cleaning will take longer, as both, the system and the media need to be heated up all the time to operational temperature. A one tank system offers all the flexibility that is needed if a variety of different products is made in one line and require different cleaning agents. Or if it must be ensured, to separate batches. Cross contamination can be safely avoided if the cleaning liquids are not reused. Also if CIP is done rarely, it often makes no sense to buffer the cleaning agents. A huge load of material that need to be cleaned out of the system, is another reason. Storing dirty caustic is not practical, if it can not be used for a first flush. Last reason for a one tank system, maybe even portable, would be the small installations, that want to clean professionally, but don’t have the space and the financial opportunities to install a huge CIP system.
Supporting the above mentioned approaches, Baumer supplies scaled packages of sensors to fulfill all quality and safety requirements. This starts with a set of four sensors. The CleverLevel level switches LBFS will ensure that media is always available to the supply pump, protecting the tank from being damaged by overflowing. The cleaning process is controlled with two sensors supplying the information defined by Sinner in the quality measuring point of the return line. Temperature and velocity will in this case be measured by FlexFlow flow sensor PF20H. Integrating the calorimetric technology with IO-Link will support this two readings in a very simple way. The conductivity sensor CombiLyz AFI for the concentration control is a very compact and fast responding conductivity sensor that also can back up the temperature reading with another signal to compare. With a very small investment the user can achieve a smart CIP control. Recording the data will support the traceability of the process in the relevant GFSI audits.
In a standard CIP system there are a variety of tanks. To keep it simple it is limited to three in this example. The water tank will enable to reuse water that is nearly as good as fresh one. Usually it is the last flushing water that is used for the next first flush, pushing out the majority of residuals directly. It might even be used between the caustic and the acid step if it is of high quality. The caustic is usually used at a temperature between 55 and 80°C. So it makes sense to isolate the tank to save the energy between the cleaning cycles. The more heat can be stored in here, the least energy is needed to heat up the caustic, and therefore also the cleaned system. This will save energy, but time as well. The installed temperature sensor TE2 points into a relevant zone at the middle of the tank with 20-30cm ingression depth. This shall prevent to pick the temperature from an outer layer of caustic that is not representative. As the acid tank mostly operates at room temperature, there is neither isolation nor temperature measurement. All tanks have a low level detection as final warning to be empty, but also a top level sensor that protects the vessel against mechanical damage. The level of caustic is measured with a hydrostatic pressure sensor PBMH. The available amount of acid is in this example controlled with the radar sensor RR30. It could also be an ultrasonic level sensor UNAM if there is no foam, stream or uneven surface bothering the signal. The level measurements help to ensure that for the next cleaning cycle the required amount of cleaning agent is available. The limit switches and pump protection are done with CleverLevel sensors. The LBFS is the basic solution in the dedicated tanks. The PL20H sensors are used where flexibility of detecting completely different liquids is important. Another strength is the choice to either detect or neglect foam.
The quality measurement point is supported with the EMF CombiFlow PF75H. As all sensors discussed here, the EMF is designed following the requirements of 3A and EHEDG. This robust and fully stainless steel made sensor enables controlling the velocity on a much higher level than a calorimetric sensor. Like the CombiLyz AFI4 it is equipped with the Baumer DFON graphical display. This does not only support the operator with good readable large figures, but also changes color when the value is out of the desired range. Simple set up and operation come along with both. The temperature sensor PT20H may not be able to utilize the fastest t90 time on the market in this application, but it will support the entire system with a high class signal. In this set up, the sensors allow to run the system directly on the spot, saving time, energy and water with high class signals as no safety margin need to be involved.
Full automatic set up
At the final stage the CIP operation and documentation will be completely automated. This includes not only the cleaning. As energy monitoring gains more importance since a decade, also a smart option to monitor the heat consumption for each cleaning cycle is a valuable investment. In this example the FlexFlow PF20H measures temperature and volume of the hot water supply of the heat exchanger. The data can be used to benchmark different cleaning cycles, but also to report the value for a carbon footprint.
The described system also includes the automated dosing of cleaning agents and composites, using the very compact CombiFlow PF55S. The electromagnetic flow meter ensures exact dosing and as well here, the opportunity to record the amount of concentrates used for every cleaningcycle. The content of the concentrate canister can be measured form the outside with apacitive sensors CFDK25. To protect the environment, the system usually will be installed in a sealed basin. Leakages rinsing into this basin the will be detected with either a CleverLever PL20H or with an optical switch type FFAM installed in the lowest point of the system.
PP20H pressure sensors installed on the way to and on the line from the cleaned process, will supply the valuable information if leakages appear or the system gets blocked at a certain stage.
All three described systems supply the user with the necessary safety that the cleaning cycle worked in the defined frame. High quality cleaning is not a question of investment. Also simple systems support both, cleaning and documentation to prove the quality promised was fulfilled. The shown solutions follow a concept that allows to grow with the tasks. All the sensors come with the hygienic and food contact materials certificates. 3A, FDA and EHEDG are the basic requirements they fulfill on the wetted parts. The housings are made from stainless steel and used with the suitable connector, supply IP 69 ingression protection. Not only to ensure food safety, but also to save energy, water, cleaner and time, the hygienic design plays a major role. Baumer supplies not only dedicated standard process adapters, but offers with the Baumer Hygienic Connection as well a simple, but in the daily operation, high end solution for flush mounted sensor integration to the product line. The DFON display is another standard part we use with a variety of flow, temperature, pressure and conductivity sensors gathered in our CombiSeries. Simple handling and economical spare part stocking follow from both standard technologies.
Size does matter, if it come to installation costs. But size does not have to matter when we consider food safety and efficient CIP cleaning. Baumer supplies the technology from very simple systems up to the full blown automation systems with the same level of professional automation and traceability. The sensors are designed to perform in this environment and ensure long lasting good results. One stop shop for all required technologies enables to create a robust, reliable, easy to handle system that suits exactly to the need of the operation and documentation.