Clean-in-Place (CIP) is one of the most common unit operations throughout the industrial sector and is crucial in order to clean process equipment between different batches. Today, these processes are fully automatic with central CIP stations installed which serve the whole plant’s process equipment cleaning and sanitation needs. They enable cleaning cycles inside pipes and tanks which are otherwize inaccessible for plant staff. Typically it includes the following steps:
CIP with ozone
Ozone technology presents a novel approach to sanitizing process equipment with significantly lower water, chemicals and energy demand. Ozone completely replaces costs and handling of traditional sanitation methods using chemicals or hot water. Ozone leaves no residual chemicals after use, eliminating the need for a final rinse. Additionally, it is possible to directly apply ozone after cleaning, known as ozone rinsing. This allows for a 3-stage CIP process instead of the traditional 5 cycles. The figure below illustrates CIP improvements that can be made by replacing chemicals and utilizing the unique characteristics of ozone. It shows how a 5-stage CIP cycle can be reduced to a 4-stage cycle.
Mellifiq’s RENA Vivo systems are a perfect fit for CIP applications, which offer a complete turn-key solution which can be integrated easily into existing plants or connected during construction of new facilities.
Hot water sanitation is commonly used where chemical use is to be avoided. However, it is time consuming and exerts strain on the mechanical equipment during expansion and contraction during heating and cooling, causing leakages and expensive maintenance. Since ozone leaves no residues, it is a viable cold sanitation method in lieu of hot water use, which saves major amounts of energy and associated costs.
Ozone is produced in-situ and on demand, which means that it is generated and applied when it is needed. This is the key characteristic of ozone compared traditional chemical agents. The figure shows the ozone concentration over time for a facility. The green area exemplifies the range of ozone concentration applied on the process equipment. As can be seen below, the ozone contration increases over time and reaches adequate levels for disinfection in just a few minutes.
The sanitation cycle is complete in 5-15 minutes depending on the amount of microorganisms and type. Since ozone is approximately 10-1000 times more effective than other chemicals against bacteria, mold and viruses, the sanitation can be ended in only a few minutes, saving important down-time for any type of facility. Typical target ozone concentration is 1 ppm for 3 log reduction of all types unwanted microorganisms in 15 minutes. Please read more about ozone disinfection mechanisms at our Disinfection application section.
Brewery clean in-place with ozone
While CIP refers to cleaning and sanitation of the interior of process equipment, COP refers to surface sanitation of tanks, pipes or floors. Typically, foaming agents are used to aid the visual inspection of cleaned versus non-cleaned areas. RENA Vivo presents the opportunity to avoid exposure of chemicals during COP operations by using an ozone system to produce ozone on demand and in-situ. The use of ozone provides a clear indication of successful sanitation as it leaves behind a subtle odor.
Cooling towers and closed water systems
These types of applications differ in some respects from CIP applications. In closed cooling systems or cooling towers, large volumes of water circulate with very long hydraulic retention. In these instances, ozone concentrations below 0.2 ppm suffice to prevent microbial growth. With large hydraulic retention times, existing biofilm can be degraded effectively.
You can read more about Cooling towers here.
Due to the strang disinfection power of ozone, existing biofilm can be removed by ozonating over an extended time period, allowing ozone to break down cell walls and organic material. Biofilm may occur in systems where insufficient sanitation or cleaning has allowed for biological growth of bacteria on organic material left from production. In such cases, ozone is an excellent way to remove the biofilm and prevent future growth.