Comprex® Magazine
CIP Cleaning in Modern Plant Operation
Find out how modern CIP cleaning can reduce water, chemicals and downtime, and how air-water pulses improve mechanical cleaning efficiency.
Introduction
Why do many companies still clean their pipelines with CIP processes that are almost the same as they were 20 or 30 years ago? It is a fair question. After all, everyone is talking about Industry 4.0, data-driven processes and highly automated production plants. Yet many CIP systems still follow outdated cleaning patterns. In practice, this is easy to see: long water flushes, high chemical consumption, high energy demand and drawn-out downtimes are still standard in many plants. While CIP cleaning works reliably, the key question is whether it is truly optimized from a technical point of view.
This is relevant not only for standard production lines, but also for more demanding tasks, from complex production systems to pipelines carrying viscous media, where reliable cleaning and flushing are critical for stable operation. In this article, we take a fact-based look at where CIP cleaning still has potential and why mechanical cleaning in particular is often an underestimated lever.
The most important facts in brief: CIP cleaning is now a fixed standard in hygienic production processes. In many companies, however, it still runs according to outdated cleaning logic. Water consumption, chemical use, energy demand and downtime in particular show that many processes are not yet technically optimized. The greatest remaining potential lies primarily in mechanical cleaning. Companies that specifically optimize their CIP systems can save resources and significantly improve cost efficiency.
Important Note Before We Begin
Before we go into more detail, one point is important: all statements in this article are based either on published studies or on documented industrial experience. At the same time, every CIP process is product-specific. This means that every design and every optimization must ultimately be validated individually.
What Does CIP Cleaning Actually Mean?
CIP cleaning, or Clean-in-Place, is usually an automated process in which systems are cleaned without having to be dismantled. This is precisely what makes it the industrial standard in hygiene-sensitive sectors today. Whether in food, beverage or pharmaceutical production, CIP cleaning is established wherever reproducible cleanliness and safe processes are essential.
A modern CIP system offers clear advantages over manual cleaning processes. With standardized clean-in-place equipment, cleaning becomes controllable and repeatable. At the same time, processes can be automated and documented, which is especially important in highly regulated industries.
The Classic CIP Cleaning Process
The basic sequence of a classic clean-in-place process is very similar in most plants. Usually, the process begins with a water pre-rinse. This is followed by cleaning with an alkaline solution. The system is then rinsed with water before an acidic cleaning phase is carried out. Finally, there is a final rinse with water. Each of these steps has a specific function. The pre-rinse removes coarse residues. The alkaline phase dissolves organic contamination. The acidic phase removes mineral deposits. This structure has proven itself and is firmly established in many clean-in-place systems. That is exactly why it is worth taking a closer look at where optimization is still possible within this established process.
The 4 Key Factors in CIP Cleaning
The actual cleaning performance of CIP cleaning is always based on four factors. Only when these four factors are considered together does it become clear where there is still optimization potential today.
Mechanical Force
- Flow within the system
- Shear stress on the pipe walls
- Crucial for removing deposits
- Directly influences the efficiency of pre-cleaning
Chemistry
- Use of alkalis, acids or enzymes
- Dissolves organic and mineral residues
- Supports the removal of stubborn contamination
- Can be reduced when mechanical cleaning is more efficient
Temperature
- Accelerates chemical reactions
- Supports the effectiveness of cleaning media
- Increases the solubility of residues
- Also increases energy consumption at higher levels
Time
- Often used to compensate for weaknesses in the process
- Frequently leads to unnecessarily long cleaning cycles
- Extends plant downtime
- Indirectly increases resource consumption
These four factors must be examined in order to understand why many CIP systems work reliably, but are not yet working optimally.
Where Has CIP Cleaning Been Optimized in Recent Years?
Looking at developments in recent years, CIP cleaning has become more efficient primarily in three areas: process control, chemistry and temperature, and media recovery. These three areas have improved CIP optimization in many companies. At the same time, one thing is also very clear: mechanical cleaning during the water phase has remained largely unchanged at its core.
Mechanics and Flow: Why More Turbulence Often Helps Less Than Expected
Let us first look at mechanics and flow. A 2018 study published in the Journal of Food Engineering examined how much higher turbulence actually helps to remove contamination. Specifically, the study focused on milk fouling. The result is sobering. Even when the flow velocity is increased significantly, from a Reynolds number of around 20,000 to 100,000, the cleaning performance during the pre-rinse only increases by around 10 percent.
In plain terms, this means that more pump power delivers much less benefit than many would expect. In practice, this often leads to a typical effect. If the desired cleaning performance cannot be achieved through more mechanical force, the rinsing time is simply extended. This has direct consequences: higher water consumption, more energy use and longer downtimes.
Interesting fact: In many companies, insufficient cleaning performance is compensated for with more time, higher temperatures or more chemicals. At first glance, this seems logical, but it often only leads to higher costs and longer downtimes. That is why it is especially worthwhile to look at the mechanical effect in the water phase. This is often where classic processes reach their limits.
Temperature: The Effects Are Limited Here Too
Temperature shows a similar picture. The study indicates that higher temperatures, at least during the pre-rinse, have hardly any additional effect above around 45 °C (115 °F). This is an important point, because temperature is still often seen as a simple lever in many plants. The technical conclusion is clear: mechanical force and temperature do help, but their additional benefit decreases significantly beyond a certain point. When both factors reach their limits, the next lever is usually chemistry.
This Is Where Real Progress Has Been Made
This is exactly where several developments have taken place in recent years. One study, for example, shows that enzymatic cleaning at around 50 °C (120 °F) can achieve similar results to classic alkaline-acid cleaning at around 80 °C (175 °F). That means up to 30 °C (54 °F) less temperature and therefore lower energy demand.
Another approach is the use of so-called single-phase detergents. These combine several cleaning steps and can reduce the need for intermediate rinsing. So real efficiency improvements have been made in this area. Nevertheless, practice often tells a different story. Many companies continue to rely on classic processes. The trend is often more about making chemicals usable for longer, reducing losses and running existing processes more efficiently, rather than fundamentally rethinking the CIP system.
Media Recovery: Measurable Savings, But Often Already Established
The third major area of optimization is media recovery. This is where processes such as ultra- and nanofiltration come into play, allowing CIP solutions to be treated and reused. One study shows recovery rates of around 75%. For certain ingredients, values of over 99% are even achieved. Another study also shows that regenerated caustic soda can deliver cleaning performance comparable to fresh solutions.
This represents a clearly measurable saving in resources and is therefore highly relevant from both a technical and economic perspective. At the same time, we hear from many industry partners that, depending on the application, chemicals are often already circulated, topped up and regularly cleaned. Here too, progress exists, but usually more as an evolution than a revolution.
The Real Weak Point: Mechanical Cleaning during Water Rinsing
Recent improvements have mainly focused on process control, chemical use and media recovery. Mechanical cleaning during water rinsing, however, still largely relies on high volume continuous flow. This creates a physical limit: wall shear stress increases with turbulence, but only up to a point. Pump capacity, pressure and pipe geometry eventually set clear boundaries. As a result, many plants compensate with longer rinsing times or more chemicals, increasing costs without fundamentally improving the process.
Our Approach: Mechanical CIP Cleaning with Air-Water Pulses
This is where our approach begins. Instead of continuous water flow, we use targeted air-water pulses based on the Comprex® process.
Small water blocks are accelerated by air pulses to speeds of up to 20 meters (66 feet) per second. This creates local wall shear stresses that can be up to 100 times higher than with classic continuous flow. As a result, contamination is reduced more effectively before chemical cleaning begins. This can lower chemical demand, shorten process time and make mechanical pre-cleaning a powerful lever in CIP optimization.
Interesting fact: Mechanical cleaning is still underestimated in many CIP systems, even though it directly affects the level of contamination before chemicals are used. When pre-cleaning becomes more effective, chemical demand, water consumption and process time usually decrease as well. This is why mechanical pre-cleaning often offers the greatest remaining savings potential.
What Savings Are Possible?
Comparable cleaning applications already show significant savings potential: cleaning cycles can be shortened by up to 80%, while water consumption can be reduced by up to 96%.
For use in CIP processes, validation with the Fraunhofer Institute is currently underway, with results expected in mid-2026. The stationary Comprex® CIP unit can also be retrofitted into existing plants without changing the overall process setup. The same principle also applies to other demanding applications, from production systems to pipelines carrying viscous media.
Where Is CIP Cleaning Heading?
The further development of CIP cleaning will depend above all on how effectively the mechanical cleaning action within the process can be improved. This is where a central potential lies: greater efficiency in cleaning time, media consumption and process stability.
Frequently asked questions (FAQs) about CIP Cleaning
What Is a CIP System?
A CIP system, or clean-in-place system, is an automated setup that cleans closed production equipment such as tanks, pipelines and fillers without dismantling them. Defined cleaning media are circulated through the system to remove product residues, biofilm and mineral deposits. CIP systems are the standard in food, beverage, brewing, dairy and pharmaceutical production, wherever reproducible hygiene and documented processes are required.
What Equipment Is Used in Clean-in-Place Cleaning?
Typical clean-in-place equipment includes CIP tanks for the cleaning media, pumps to generate flow, heat exchangers for temperature control, valves, sensors and a control unit that runs the defined cleaning program. In many plants this equipment is combined into a fixed CIP skid. The Comprex® process integrates into existing clean-in-place equipment and strengthens the mechanical effect during water rinsing.
What Is a CIP Machine?
A CIP machine is the unit that stores, heats, doses and circulates the cleaning media through a production line. Depending on the design, it runs single-use or recovery-based cycles and controls flow, temperature and dosing. The CIP machine largely determines how efficiently the water and chemical phases run, which is exactly where mechanical pre-cleaning offers additional savings potential.
What Is a CIP Cleaning Solution?
The term CIP cleaning solution has two meanings. In a chemical sense, it refers to the cleaning media used in the cycle, usually an alkaline solution, an acid and a sanitizing step. In a broader sense, it describes the overall approach to cleaning a system in place. Comprex® is a mechanical CIP cleaning solution that uses air-water pulses to reduce residues before the chemical phase, which lowers media demand and process time.
How Long Does CIP Cleaning Take?
The duration of CIP cleaning depends heavily on the plant, the product and the degree of contamination. In many classic processes, cleaning times are extended when the mechanical effect is not sufficient. This means that systems remain out of operation longer than actually necessary. Modern approaches address exactly this point. They improve pre-cleaning so that less time is needed for subsequent cleaning steps. This can significantly shorten cleaning cycles without compromising cleaning performance.
How Can a CIP System Be Optimized?
A CIP system can be optimized in several areas. These include process control, chemical use, media recovery and, above all, mechanical cleaning. In recent years, process control and chemistry in particular have been developed further. Nevertheless, many systems still work with classic cleaning principles. That is why the greatest optimization potential often lies in mechanical action. This is where the physical limits of conventional systems are reached, and where new approaches can enable significant improvements.
Conclusion and recommendations
The greatest future efficiency gains in CIP cleaning can be found where unchanged mechanical principles are still being used today. Modern mechanical approaches show that water consumption, chemical use and cleaning time can be significantly reduced when pre-cleaning becomes more effective. Instead of extending processes further or using more chemicals, the development is moving toward more efficient physical cleaning.
With our Comprex® process, we address exactly this point. Through targeted air-water pulses, based on the Comprex® process, we increase the mechanical effect within the system and create the basis for shorter cleaning cycles, lower resource consumption and a more efficient CIP cleaning process overall. Beyond classic CIP applications, the Comprex® process also supports other demanding cleaning tasks, from production systems to pipelines carrying viscous media, wherever efficient cleaning and flushing keep operations stable.
Why should you choose us?
Cleaning a heating system in a shopping center
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