Learn more about the industrial applications of a falling film chiller

Utilisation and added value of falling film chillers

Industrial Applications for Industrial Water Chillers

What’s the Process?

The water cooling with film chillers is becoming increasingly established as an efficient and cost-effective solution for heat dissipation in industrial applications. The use of film chillers is suitable wherever different consumers such as processes or individual machine parts such as spindles, motors, or hydraulic devices need to be economically supplied with a cooling unit. In addition, a customized water cooling unit is an optimal solution for demanding conditions such as high ambient temperatures and heavy dirt.

In the Falling Film Chiller or baudelot chiller the homogeneous falling film allows to chill water down to 0,5 °C. Within industrial processes it can function as pre-chiller for industrial ice bank systems or is connected to the water side of a Plate Heat Exchanger. Or will be pumped directly to various food cooling processes. From the water collecting tank under the Falling Film Chiller pumps to bring the chilled water to the desired consumption locations. Our devices generate a maximum power reserve in production with this baudelot cooler at this temperature. Different from PHE's, there is no need of temperature control, hot gas-defrost or flow control on water side. Costs for controller and temperature sensor do nor depend on the capacity. Control valves and pilot valves as well as solenoid valves and additionl shut valves are dempendent on capacity.

An industrial water cooling system with film chillers is a type of water cooling that extracts heat from a heat source while ensuring constant temperatures, pressures, and flows through a cooling system. Simply put, an industrial water cooling system works by circulating a cooling fluid from a reservoir to the devices that need to be cooled. This differs from other cooling systems, such as air-based systems, which use fans for heat dissipation.

Industrial water cooling systems with falling film chillers have become popular in various cooling and large-scale installations due to their higher efficiency compared to certain air cooling systems. However, their suitability needs to be evaluated on a case-by-case basis. This decision is indeed crucial as choosing the right type of cooler can help businesses save costs, reduce downtime, and improve energy efficiency.

As mentioned earlier, industrial water cooling systems with FFC are part of cooling systems that are responsible for removing unwanted heat from a source. There are various applications where this can be useful, such as plastic processing processes, including various operations in mechanical forming, metal and machinery manufacturing, reducing issues like thermal deformation and improving accuracy, the food and beverage industry, chemical and pharmaceutical production, medical facilities for operating systems like MRIs or X-ray machines, as industrial water cooling systems to supply multiple buildings or facilities with chilled water through a pipeline network, or even in modern data centers, where they contribute to the cooling of equipment to ensure their operation within safe temperature ranges.

Industrial Ice chiller in dairy processes

Falling Film Chiller continuously generates cold water at 0.5°C without ice formation. Water is the ideal cooling medium for milk-processing plants, because it is non-toxic, has excellent heat transfer and transport properties, is inexpensive and available everywhere. To meet high global quality standards, fast and smooth cooling processes must be guaranteed from processing to storage of sensitive dairy products such as milk, milk powder, yoghurt, milk desserts, butter and cheese, mostly at the expense of high energy costs.

Milk processing plants are therefor looking for partners such as Heat Transfer Technology AG in order to realize saving potentials in the field of low temperature water technology. In order to expand the capacity of a dairy, operators often install additional cold water storage tanks. This is associated with high financial cost and space requirements. A corresponding alternative is the use of a Falling Film Chiller for water pre-cooling. In addition to the robust, simple operation and high energy efficiency, the advantages are that water temperatures between 0°C and 1°C can be generated without risk. Falling-Film Chiller cool the returning water, before it enters the water storage tank, thus relieving the existing plant.

Low-specific and thermodynamic parameters from an industrial chiller of ice water near freezing point

As zero point is approached, the problems in ice water production calls the attendant risk of ice formation increase. The known anomaly of water (lowest specific volume at 4°C) results in the water volume expanding when it freezes, and under certain circumstances this can cause destruction of the equipment used. Furthermore, ice formation in water systems with their thick layers of ice always involves considerable performance losses because the ice layer acts like insulation and greatly reduces the thermal transmission output.

Consequently low temperature water production calls for a technique that on the one hand brings the water temperature as close as possible to zero point, but on the other hand is not susceptible to potential ice formation. If control fluctuations of the cooling system lead to ice formation, a layer of ice on the panels will reduce the heat transfer and reduce the cooling power of the baudelot ice water cooler. Building of ice at the panels may occur for some minutes, but there will not follow any mechanical destruction as in Plate Heat Exchangers. Ice will melt automatically after raising of the temperature inside the panels within the next normal operation mode cycle.

The flow-specific and thermodynamic parameters of water are favorable, so that high heat transfer rates can be achieved. However, the freezing point of the water itself (zero point) sets crucial physical boundaries for ice water production and cooling with ice water. Above all, temperatures achievable in the water are made to approach the zero point as closely as possible in order to exploit maximum temperature differences for the products to be chilled with ice water and to keep the temperature of the cooled product as low as possible.

Process water chiller with discontinuous inlet water flow

This Falling Film Chiller or baudelot ice water cooler is designed to be robust to unexpected fluctuations in operation. For this purpose we use a split-tank-design is the optimal solution for cooling water with inconsistent flow rates or temperatures, ensuring that your refrigeration machine operates continuously and efficiently. The Falling Film Chiller or Baudelot ice water cooler achieves this by incorporating a custom-designed water reservoir and flow path that caters to the specific flow profile and temperature variations of your application. This unique design ensures the chiller is resilient to unforeseen operational shifts while maintaining high-performance levels. Additionally, by employing food-grade stainless steel in its construction, the Ice Water Falling Film Chiller meets all necessary standards for use in the food and beverage industry, ensuring a hygienic and reliable cooling solution for your business.

Falling Film Chiller versa Ice Bank

Ice storage adapts quickly to changing cold demand. This applies to energy consumption, energy costs, investment costs, as well as availability of space and electricity. Most often, our customers are faced with the choice of a storage system or a falling film chiller. By using storage, high peak cold consumption can also be managed with cooling systems that are only designed for the daily average value. There is no doubt that an ice storage system can be operated more efficiently by taking advantage of the favorable off-peak hours.

On the other hand, Buco falling film chillers are much cheaper to purchase and, in addition to lower energy consumption, also require less space. The past clear advantage of storage in the use of partial load operation has diminished over the years and has become differentiated in that falling film chillers can also be used in partial load operation with fluctuations in water temperature or quantity.

Our falling film chiller is a special heat exchanger designed with pillow plates to create an evaporation environment inside, while the outside of each pillow plate allows for even distribution of water, forming a thin film measuring 0.5-0.4 mm in thickness as it flows down each plate, supporting efficient cooling or heating applications in industrial technology.

Falling film chiller technology has revolutionized the technical industry, especially in the food and beverage industry, as well as in the chemical and pharmaceutical industries. The exchange coefficients depend on how thin or thick the water film flows down or is applied to the plates - thinner layers result in higher coefficients. However, the use of a smaller number of plates with the same water flow rate can lead to thicker films that lower the coefficients.

De-oiling device of a baudelot ice water cooler

If the Falling Film Chiller is used with NH3, a de-oiling device for the system is provided as a small suction pipe at the liquid bottom header of the system for gravity or pump operation. This is standard for NH3 and done on request for CO2. With refrigerant NH3, and depending on the oil, probably as well for CO2, there are severe miscibility gaps or solubility gaps with different oils, even if helpful additives are used. Prior to the de-oiling procedure the evaporator system must be out of operation for some time, to allow the oil to separate to the bottom of the system.

In case of using oil with a lower density compared to the liquid refrigerant CO2, the refrigerant has to be evaporated completely for this de-oiling function. A regular de-oiling is needed, according to the properties of the refrigerant compressor and the oil. Experienced engineers with academic advice are responsible for the design. Individual channel design and construction for each project due to the high inside film coefficient and low pressure drop.

Why mainly NH3?

The natural refrigerant ammonia, which is not only climate-neutral, but also highly energy-efficient, is normally used. Due to its very good thermodynamic properties, ammonia requires the least amount of energy to generate a certain cooling capacity.

This advantage is particularly important in dairies with their large plants, so that refrigeration plants using ammonia have proven their worth in the milk processing industry. At the same time the ammonia volume in this system is low. Gravity-driven evaporators with separators are used. In this way, the efficiency of the system is increased compared to plants with direct expansion and energy costs are reduced. For heat recovery, effective systems use an evaporative condenser, a heater and oil cooler. All in all, this increases the efficiency of the entire system an reduces operating costs.

The Baudelot cooler

Historical review and beginnings of an industrial chiller

Jean Louis Baudelot (1797–1881), was born in France, and studied engineering in Belgium. Though he claimed several inventions, fame came in 1856, when he patented a liquid cooler. Specifically intended for the brewing industry.

A cousin who was a brewer presented him with the fact that until then beer worts had to be cooled in a shallow vessel (cool ship) and stirred during a whole night—a process that easily took 8 hours. Worse, the continuous exposure of the worts to the air resulted often in unwanted inoculation and infected beer. Yet exposure was mandatory because beer yeasts need oxygen at the outset of fermentation. Therefore, the wort needs to be well aerated.

Baudelot envisaged a fine double copper sheet overlaying copper tubes (first cylindrical, later elliptical in cross-section) wherein cold water (spring water or icewater) ran countercurrent to the worts. The worts were collected on top of the cooler in shallow tray, and then finely dispersed, flowing over outside of the copper sheets, which were being being cooled internally. In this way, cooling took place in less than a quarter of the original time needed, limiting exposure to contaminating microbes, while aeration was assured. Hot wort flowed like an undulating waterfall down the exterior of the cooler, emerging cool and aerated at the bottom. It was a massive improvement that led to beer of much better quality and stability.