Key Principles of Rotary Evaporation

Rotary evaporation is one of the most widely used techniques of evaporation offering excellent distillation and extraction performance. Rotary evaporation is most often used to remove a volatile substance from a liquid mixture and is carried out using a rotary evaporator. This article will outline how rotary evaporation works, some key principles, and its applications.

Rotary Evaporation Working Principles

Rotary evaporation works on the principle that reducing the pressure on the solvent results in the analytes within have a lower evaporation point than at atmospheric pressure. Rotary evaporation is used in both preparative and analytical organic chemistry and can assist users in fractionating liquid-phase mixtures to illustrate their composition or to purify particular compounds of interest. Rotary evaporation application is varied and it is a process that is used by chemists in consumer good manufacturing, biotechnology, pharmaceuticals, and more.

Rotary evaporation allows for a faster rate of extraction, collection, and analysis of remnant or solvent substances than other evaporation techniques. Rotary evaporation using a traditional rotovap is extremely beneficial but highly inefficient, leading to high usages costs and laboratory space needed.

The size of a sample or solvent can have a substantial impact on the specifics of rotary evaporation. However, the general principles and methods using Ecodyst’s revolutionary model remain the same.

Step 1 – The solvent is placed into a glass flask and placed on top of an energy-saving heater. The size of the flask container varies with loads up to 200 liters being serviced.

Step 2 – The solvent is heated and stirred constantly to ensure that it arrives at the necessary temperature which is below its boiling point at room temperature.

Step 3 –  a chemical reaction takes place and manipulates the substance to begin the evaporation of the liquid. The vital solvent parts are separated from the waste and the waste is then drained through a tap fitted below the flask.

Step 4 – the evaporated substance is held in a glass tube, using a power suction mechanism that moves it to a self-cooling unit.

Step 5 – when the substance is cooled to the required level, the remnants drop into another flask. The flask size depends on the size of the original solvent sample.

Benefits of Rotary Evaporation

Traditional rotary evaporation setups involve the use of many interconnected instruments and accessories, such as a water bath, condenser tube, and rotating container flask. This setup is specifically designed for rotary evaporation, meaning it is purpose-built and will not be used for any other experiments.

Conversely, the downside of using a traditional rotovap for rotary evaporation is that it has a relatively large footprint. This means that from a space-saving and lab flexibility perspective, traditional rotovaps are inefficient.

To combat this problem, Ecodyst designed a range of rotovaps that compound the elements of rotary evaporation into a smaller, more flexible footprint.

What is Rotary Evaporation Used For?

Rotary evaporation is used for evaporation, crystallization, separation, drying, concentration, solvent recovery and is particularly used for the continuous distillation of solvents under decreased pressure. As there are so many varied application purposes, there are many industries that can benefit from the use of rotary evaporation such as pharmaceuticals, biological and food production.

To find out more about rotary evaporation and the many ways it can be used, take a look at further resources here.

50 l Rotary Evaporator for Large Scale Solvent Recovery

Large-scale solvent recovery can prove a difficult, inefficient challenge that takes a lot of time and energy. 50 l rotary evaporators from Ecodyst are a brilliant means of mitigating these issues. This blog post will examine why 50 l rotary evaporators are so beneficial and outline some of their key attributes.

What is a 50 l Rotary Evaporator?

50 l rotary evaporators are large-scale rotary evaporators that work to gently and efficiently take solvents out of a range of sample types including polymeric materials, inorganic and organic analytes. A vacuum is induced by the 50 l rotary evaporator, reducing the boiling point of the sample that is being heated. This means that the solvent can be vaporized at a significantly lower temperature than the standard boiling point, making rotary evaporation a highly efficient and economical process.

What Makes Ecodyst’s 50 l Rotary Evaporators Different

Ecodyst’s 50l rotary evaporators are at the forefront of evaporative process technology, being one of the first 50 l rotary evaporators to employ metal condensers. The refrigeration line on the 50 l rotary evaporator can be directly attached to the condenser coils as metal is highly conductive as well as strong.

Our EcoChyll X7 is a high-speed evaporator that facilitates fast, continuous cooling for rapid and efficient recovery. This 50 l rotary evaporator utilizes Ecodyst’s patented intelligent direct self-cooling condensers with minimal manpower required for every evaporation.

Ecodyst’s industrial-scale 50 l rotary evaporator is a turn-key solvent recovery system that is renowned by botanical extraction processors and chemists throughout the world.

Our 50 l Rotary Evaporator is Environmentally Friendly

Ecodyst’s 50 l rotary evaporator bypasses cooling systems that make use of objectionable techniques and materials, whilst consuming a large amount of energy. This means that evaporation using our products is more environmentally friendly.

Traditional 50 l rotary evaporators use many gallons of tap water year by year. Our systems save large amounts of energy which would usually be spent cooling anti-freeze without wasting dry ice.

A More Cost-Effective 50 l Rotary Evaporator

Our 50 l rotary evaporator is more cost-effective as it does not use costly rotary motor mechanisms. This means that the cost-per-use with our systems is significantly lower. Because our systems are easy to use and install, manpower costs are also greatly reduced.

Our 50 l Rotary Evaporator Prioritizes Convenience

Our range does not have any large evaporation vessels that need to be removed, making them significantly easier to use. This in turn enhances the efficiency of the users.

If you would like to find out more about the 50 l Rotary Evaporators from Ecodyst, get in touch with us today.

A Rough Guide to Continuous Cooling

Continuous cooling is a key benefit of the Ecodyst rotary evaporator range. Rotary evaporators work to gently and efficiently remove solvents from a range of samples. Samples are heated and their boiling points are minimized concurrently using a vacuum that is induced by the rotary evaporator. The boiling point decreases as the pressure reduces and this means that the solvent can be vaporized at a far lower temperature than the standard boiling point.

The Importance of Continuous Cooling in Rotary Evaporation

One of the major downsides of traditional rotovaps is that they produce a high level of material waste and costs, due to the use of water or dry ice. Ecodyst’s rotary evaporators offer a continuous cooling technology that does not require the use of dry ice or water.

An efficient, continuous cooling system is required to mitigate the problems that commonly occur with traditional cooling condensers. A high-efficiency, a continuous cooling system is extremely advantageous to decrease overall size, complexity, weight and improve cooling temperature and function of the condenser cooling system.

Continuous Cooling with the Ecodyst 100L EcoChyll X7 Hi-Speed Evaporator

This large-scale rotary evaporator blends high loading capacities with extremely fast, continuous cooling for quick and efficient solvent recovery. Continuous cooling with this model is made possible using direct, self-cooling condensers which have a high cooling capacity. Their large surface area condensers can reliably condense high volumes of solvents.

This industrial-scale, continuous cooling rotary evaporator is a staple in research and commercial laboratories, highly recommended by chemists and botanical extraction processors. Our smart, self-cooling system is energy efficient and eco-friendly. Our continuous cooling system guarantees a productivity enhancement for high throughput solvent recovery as well as decarboxylation applications.

Our rotary evaporators are not only designed to function well, but they also prioritize user safety and ease of use, meaning that they do not require specialists for use.

Using Ecodyst Hydrogen for Continuous Cooling

Ecodyst’s Hydrogen model is an innovative means of continuous cooling which has a small footprint and is eco-friendly. This product sets a new benchmark for rotovaps which do not need to use glycol, water, or dry ice and instead implement Ecodyst’s continuous cooling technology. The built-in condenser leads to faster rates of evaporation which in turn enhances productivity.

This innovative, continuous cooling technology has been a game-changer in the rotovap industry, leading to minimal downtime.

If you would like to find out more about how our rotary evaporators make use of continuous cooling systems, get in touch with us today.

The Sustainable Rotary Evaporator from Ecodyst

Rotary evaporators (sometimes called rotovaps) are a feature of many chemistry laboratories. Whilst new models of rotary evaporators are developed year by year, there has not been a significant change in the way they operate since their invention in the 1950s.

However, recently, Ecodyst has pioneered revolutionary rotary evaporator technology which minimizes costs and environmental impact whilst also offering enhanced performance and simplified operation.

The History of the Rotary Evaporator

Conventional rotary evaporators have some downsides, despite being widely used. This is largely due to the use of glass condensers. Glass is often used in chemistry applications as it is low in cost and has a high chemical resistance. However, glass is a poor conductor of heat meaning that traditional rotary evaporators have had to work harder to stay hot, thus increasing the energy usage and making them less sustainable.

Rotary evaporators are also expensive to operate, inefficient at vapor trapping, and make managing dry ice and solvent mixtures extremely time-consuming.

How Ecodyst Solved Sustainability Issues

Ecodyst overcame limitations of rotary evaporator design, reimaging the unsustainable, inefficient elements of the production. Ecodyst rotary evaporators use a metal condenser coil which is coated with a chemical-resistant polymer. This change creates advantages over the traditional glass condensers.

Ecodyst’s Ecochyll X1 condenser is more sustainable as it offers enhanced thermal conductivity and more energy-efficient cooling when compared with glass. It is also extremely durable, with a large surface area which allows for customization the metal condenser is also strong enough to be connected with a pressurized refrigeration system meaning that there is no need to recirculate glycol or water-saving energy, time, money, and hardware costs. This also reduces the overall space in the laboratory that the rotary evaporator requires. The only operating cost that this rotary evaporator requires is the energy which is around half that required for traditional glass rotary evaporators.

A Range of Rotary Evaporators to Suit Laboratory Needs

The EcoChyll X7 and X9 are large scale models which can facilitate up to 200 liters in just one solvent recovery process. This means that less energy and manpower is required for each evaporation. Conversely, EcoChyll S and Hydrogen are designed to be small-scale, benchtop rotary evaporators for situations in which space is important.

EcoChyll S and Hydrogen are both able to achieve a fast cool down, reaching -40°C in one minute. They are both always available which leads to a more sustainable model, increasing productivity, saving money, and eliminating downtime.

Ecodyst’s Rotary Evaporators

As Ecodyst’s rotary evaporators bypass cooling systems which use high amounts of energy and are less sustainable in the long term, our rotary evaporators are more environmentally friendly and energy-efficient. Our rotary evaporators have no need to use the thousands of gallons of tap water each year, or use dry ice or use large amounts of energy cooling antifreeze.

For all of the reasons outlined in this article, Ecodyst’s model offers a more sustainable approach to rotary evaporation. If you would like to find out more about our rotary evaporators, contact us today.

What is Distillation? Principles and Applications

Distillation is a technique for the separation of mixtures based on differences in the conditions necessary to alter the phase of components in the mixture. This is a widely used technique in which mixtures of liquids are heated to mean components which have different boiling points into the gas phase. This gas is then condensed and cooled.

Rotary evaporators provide a means of reduced pressure distillation, where the residue is retained rather than the distillate.

Applications of Distillation

Distillation is used for a number of applications such as distilled water, kerosene, gasoline, and many other liquids. Gases may also be liquified and separated, such as nitrogen, oxygen and argon which are distilled from air.

Water from natural sources contains a broad range of minerals and other impurities, many of which are removed via distillation. Distilled water is often used when the presence of minerals could impact the effectiveness of equipment, including in steam irons.

Distillation is a part of the production process of a range of alcoholic beverages such as brandy, whiskey and rum. When plant and fruit materials ferment, ethyl alcohol in a dilute form is produced, distillation is used to purify and concentrate the ethanol.

Distillation of crude oil can produce a range of products, as each of these products has a unique boiling point. A process known as fractional distillation is used to refine oil into a range of materials.

However, distillation alone cannot remove all unwanted lipids such as fats and waxes from oil extracts. This has an impact on the quality of the end-product, leading to a reduction in potency and clarity. Rotary evaporators can be employed to winterize oils and enhance their overall quality.

Using Rotary Evaporators in Distillation Applications

Rotary evaporators are becoming more widely used for distillation applications. Distillation via rotary evaporator is faster than traditional methods as solutions are distilled under reduced pressure at a lower temperature, speeding up the process because of the larger surface area.

Using a rotary evaporator for distillation also saves space in the lab as one piece of equipment can be used for multiple applications.

Rotary evaporators also save energy over traditional distillation methods, as they do not need to heat the mixture to such high temperatures. This also reduces the degradation of temperature-sensitive components which could adversely impact the reaction.

Rotary Evaporators from Ecodyst

Ecodyst’s rotary evaporators are cutting edge solvent separation devices and range in scale from large-scale 200l rotovaps, to benchtop models. These rotovaps are more environmentally friendly as they consume less energy by by-passing cooling systems.  They are also easy to use, with no large evaporation vessels which require removal. These systems were developed to increase the efficiency of users’ experiences.

To find out more about how rotary evaporators from Ecodyst can help with the distillation applications, contact us today for more information.

Ethanol Removal in Cannabis Applications

Extracting cannabinoids and other compounds from raw cannabis can be done using a range of techniques. The most popular techniques are extraction using CO2, ethanol or a hydrocarbon such as butane. The selection of one of these techniques is based on a range of factors such as the final application of the product (such as what form it will take and whether its for recreational or medicinal use). It is also important to know the amount of raw material to be processed.

This article will focus on the method of ethanol extraction which can be done in a range of methods such as warm, cold or room-temperature processing. Lots of ethanol extraction processes require the use of a rotary evaporator to remove the ethanol from the extract solution.

This article will examine the method of ethanol extraction for cannabis applications, particularly focusing on ethanol removal with the use of a rotary evaporator.

How Ethanol Extraction Methods are Used for Cannabis Applications

There are three main methods of ethanol extraction which are:

Cold Process – this is when the cannabis plant is soaked in ethanol which has been chilled, stopping undesirable compounds such as waxes and pigments from turning to solids, however, it also means the extraction of desired compounds is slower.

Room Temperature Process – similar to the cold process, room temperature ethanol extraction involves raw cannabis being soaked in ethanol at room temperature to pull out soluble compounds. The cannabis is then removed and the solvent is evaporated.

Hot Process – this process involves using hot ethanol to solubilize compounds and requires the use of specialist equipment. This ethanol removal method is difficult to scale up and can lead to undesirable compounds ending up in the solvent.

Ethanol removal is popular for several reasons. It can extract a large range of compounds from cannabis plants, as well as the process being refined to stop certain compounds from solubilizing. It can also be scaled so it’s suitable for processing extremely large volumes of cannabis.

A Brief Guide to Ethanol Removal

Step 1: the plant is soaked in ethanol, causing certain compounds inside the plant to solubilize with the specific compounds extracted being dependent on the temperature of the ethanol and the makeup of the plant.

Step 2: After a sufficient amount of time the plant is removed from the mixture.

Step 3: The next step is the winterization process, which involves more ethanol followed by rapid cooling to remove lipids.

Step 4: the solvent must be removed for the solution, typically using a rotary evaporator.

Step 5: High purity cannabis oil remains, often with some residual solvent. This is removed by drying the oil in a vacuum oven.

Rotary Evaporators for Ethanol Removal

Rotary evaporators are extremely efficient in the removal of volatile solvents from non-volatile samples. Rotovaps decrease the solvent’s boiling point, minimizing exposure to heat, which is particularly important for temperature-sensitive compounds. Rotovaps are also environmentally friendly and have excellent repeatability.

At Ecodyst, we supply a range of innovative, eco-friendly, and simple-to-use rotary evaporators for ethanol removal of any size as well as other solvent recovery. To find out more, contact us today.

The Modern Rotary Evaporators: Ecochyll X1 and Hydrogen

Rotary evaporators, also known as rotovaps, are a common sight in most chemistry labs. Perhaps surprisingly, this familiar piece of equipment hasn’t changed much since it was first invented in the 1950s. Even though new models of rotary evaporators are developed each year by major manufacturers, the basic principles of operation have remained the same. Until now, that is. In this article, we take a look at how Ecodyst is revolutionizing the world of rotary evaporators; eliminating costly consumables while offering better performance, simpler operation and drastic reductions in lifetime costs.

Rotary Evaporators 101

The first rotary evaporation system in scientific literature was described in 1957 by researchers at the Rockefeller Institute for Medical Research in New York.1 These researchers placed a dilute solution in a round-bottomed flask over a heat source. This flask was connected to another round-bottomed flask, which was partially submerged in an ice bath. The two connected flasks were then evacuated using a vacuum pump and rotated about their axes for even heating and cooling.

Original schematic for a rotary evaporator (Anal. Chem. 22, 1462–1462 (1950))


By evenly heating the flask containing the dilute solution at reduced pressure, the researchers could easily evaporate the solvent from the solution, which was then condensed in the cooled glass condenser. This yielded a concentrated solution in the heated flask.

Early improvements to this original design included the use of a hot water bath rather than a burner, and the insertion of various traps between the evaporation flask and the condenser. It wasn’t long before the first commercial models were produced. Today, rotary evaporators are used at all scales, from benchtop research models (typically 1 L capacity) to larger models for pilot plants and commercial syntheses with capacities of hundreds of liters. New rotovap models often feature vapor temperature sensing and digital controls for vacuum pressure, temperature and rotational speed.

However, despite incremental changes over the last 60 years, the basic operating principles in today’s conventional rotary evaporators remain the same as they ever were.

Limitations of Conventional Rotary Evaporators

Despite their widespread use, conventional rotary evaporators suffer from some serious drawbacks, most of which can be attributed to the use of glass condensers.

Glass has traditionally been used in chemistry applications due to its low cost and resistance to most chemicals – these properties alone have made it the material of choice for the condensers in virtually all rotary evaporators. However, glass is far from ideal for this purpose: glass is a poor conductor of heat, so conventional rotary evaporators need to work harder to overcome the poor rate of heat exchange through glass condensers.

Other issues with conventional rotary evaporators include high operational costs, inefficient vapor trapping and time-consuming management of dry ice and solvent mixtures.

Revolutionizing the Rotary Evaporator

Ecodyst sought to overcome the limitations of conventional rotary condensers by rethinking several elements of its design, starting with the condenser. At the heart of an Ecodyst rotovap is a metal condenser coil coated with special chemical-resistant polymers. While simple, this change represents a paradigm shift in rotovap design and produces a number of significant advantages over traditional glass condensers.2

The metal condenser, featured in Ecodyst’s Ecochyll X1 condenser, not only offers much better thermal conductivity (and therefore more energy-efficient cooling) than glass, but is also highly durable and has a huge surface area, which allows for customization.

Crucially, the metal condenser is also strong enough to be connected directly to a pressurized refrigeration system. This means that the recirculating chiller needed glycol or water systems can be completely eliminated, saving maintenance and hardware costs as well as drastically reducing the amount of space taken up by the rotovap system.

A completely self-contained coolant circuit means that operating costs are drastically reduced compared to any other type of rotovap setup: the Ecochyll X1 means no need for dry ice, coolant or water. The only operating cost is the cost of the electricity required to power the device; which, thanks to its more efficient design, is around 50% of that required for a conventional glass condenser rotovap. Thanks to these substantial savings, the Ecochyll X1 typically pays for itself within 3-5 years of average use.

Ecodyst cooling technology not only offers cheaper and more efficient operation than competing systems, but also better performance: the efficient condenser reaches  in under a minute (compared to 45 minutes for conventional recirculating chillers) and offers much faster rates of evaporation than traditional rotovaps.


Ecodyst Rotovap Systems for the Lab

Ecodyst produces two benchtop systems for rotary evaporation: the Ecochyll X1 and the Hydrogen.

The Ecochyll X1 is a benchtop cooler/condenser engineered for best-in-class evaporation in lab environments where space is at a premium. Thanks to proprietary smart cooling technology, the Ecochyll X1 sets a new benchmark for reliability and efficiency.

The Hydrogen packs the same condenser technology into an all-in-one rotovap. Combining rotary evaporator and condenser into a single benchtop unit provides the same high performance as other Ecodyst products in a simple-to-use format with a footprint of only 1.8 square feet. Inbuilt digital controls offer precise management of all system parameters, while a remote function enables full PC control and data transfer for further processing.

Ecodyst now offers a full range of rotary evaporators, from 1L benchtop models like the Ecochyll X1 and Hydrogen through to the 200L Ecochyll X9 for process chemistry and commercial applications. Ecodyst’s unique cooling technology enables researchers and industrial chemists alike to move on from expensive and time-consuming management of dry ice and coolant systems, and reap the benefits of high-performance and low-cost extraction.

References and Further Reading

  1. Craig, L. C., Gregory, J. D. & Hausmann, Werner. Versatile Laboratory Concentration Device. Anal. Chem. 22, 1462–1462 (1950).
  2. How Ecodyst’s Modern Rotovap Revolutionizes Rotovap Technology. (2021).

Winterization of Oils to Remove Fats and Waxes

Cannabis and hemp are botanically complex, containing a rich assortment of carbohydrates, insoluble fibres, proteins, chemicals, and vitamins. Among the most valuable constituents of the Cannabis sativa and indica plant species are—of course—cannabinoids like cannabidiol (CBD) and tetrahydrocannabinol (THC). Extracting these compounds from the raw plant material and purifying it into a high-purity end-product requires a multi-step workflow, from harvesting through to winterization.

Why Winterize Oils?

Fractional distillation alone will often fail to remove unwanted lipids like fats and waxes from oil extracts. This can have a direct effect on the end-product, diluting potency, reducing clarity, and generally leading to a distillate of overall reduced quality.

Winterization is key step in the extraction and purification of oils derived from cannabis and hemp. It involves the fractional crystallization of the extract using butane or high proof ethanol at cryogenic temperatures, or liquid carbon dioxide (CO2). Cold ethanol winterization is usually preferred as it is relatively inexpensive and quick, but it tends to produce darker extracts. We compared the impact of different extraction methods in a recent article: What is the Winterization Process?

In cold ethanol winterization, the raw, unfiltered extract is mixed in the alcohol solution until fully combined then cooled to temperatures approaching -80°C. Critical winterization parameters include cooling rate, temperature of crystallization, and molecular mobility within the oil mass, as these variables directly influence the precipitation of solid fats and waxes.


Once winterization of oils and fats is complete, the heterogeneous crude mixture can then be filtered using traditional filteration equipment. It may also be decarboxylated to convert cannabidiolic acid (CBDA) into CBD, producing higher concentration extracts. The filtrate is concentrated down to separate the ethanol from the cannabinoid oil; a term often referred to as post-winterization

Post-Winterization Equipment

The type of equipment used in post-winterization depend on the method used. Both sub- and supercritical CO2 extraction typically use falling film evaporators, but such a bulky and large-scale apparatus is unsuitable for modern cannabis facilities.

Cannabis today represents a booming global industry contributing billions of dollars to economies around the world. Producers looking to drive the bottom line and increase profit margins without compromising the quality of their product offering must be able to distil and purify large volumes of oil quickly and effectively. The falling film evaporator is unfortunately unsuitable for such an initiative, particularly for small-scale laboratories looking to produce high-quality cannabinoid oils on a budget.

At Ecodyst, we have pioneered a new extraction and platform based on a proprietary cooling technology that maximises yields, quality, and time. If you would like to learn more about how our evaporators are used in post-winterization processes, why not contact a member of the team today?

High Quality Budget Rotary Evaporator from Ecodyst

Rotary evaporator users will know that whilst evaporation via rotary evaporator is an efficient, gentle process that can remove solvents from a wide range of sample types, the equipment can be extremely costly.

Many users desire a budget rotary evaporator, however, it is important that these budget instruments do not compromise on the quality and are still fit for the intended use. This blog post will detail Ecodyst’s budget rotary evaporator and the benefits that come with it.

What Ecodyst Offers

Our budget rotary evaporator has been designed specifically to be cost-effective and extremely efficient. Ecodyst was the world’s first lab equipment manufacturer to use metallic condensers in evaporation and decarboxylation processes. Our budget rotary evaporator is based on the same metallic coil technology, featuring a single-coil inside a robust, space-friendly unit. The EcoChyll X5 has a 22L capacity whilst maintaining a small footprint.

Our innovative products have created a new standard for budget rotary evaporators, with superb cost-efficiency and reliability of results. This means that there is no need to compromise on quality for a lower cost.

A Budget Rotary Evaporator from a Reputable Company

Often, a budget rotary evaporator can be bought online for a relatively low cost from websites such as Amazon. However, these rotovaps rarely come with a warranty, and when they do it is challenging to get the manufacturer to fulfill it if they are overseas.

At Ecodyst, our innovative budget rotary evaporator has been designed on a foundation of personal experience with frustrating rotary evaporator designs. Despite being lower in cost, our budget rotary evaporator has been created with a commitment to radical improvement and solid craftsmanship. Ecodyst is committed to offering superb levels of service prior to, during, and after a sale.

Many budget rotary evaporator companies do not provide an aftercare service, so users cannot contact them if they encounter problems or have questions. Not only does Ecodyst provide professional on-site or virtual installation and training with the delivery of our budget rotary evaporator, but we are also available during business hours to help with any queries you may have.

It can be difficult to get replacement parts with other budget rotary evaporator manufacturers, however, at Ecodyst we are able to overnight replacement parts to our customers if necessary. Needing to replace parts can result in downtime that is ultimately costly to your business and that is why we are committed to assisting you as quickly and efficiently as possible.

Our budget rotary evaporator is designed with the consumer in mind and is easy to use and increases user efficiency. Contact us today to find out more.

Exploring the Drawbacks of a Falling Film Evaporator

Typically, evaporation is carried out within vertical tubes. However, in some applications, process fluid evaporates outside horizontal or vertical tubes. The process fluid will always evaporate downwards due to the effect of gravity as a continuous film, creating a film along the tube walls and falling downwards. A fluid distributor is created to maintain an even liquid distribution for every tube that the solution falls down.

Falling film evaporators are widely used as an evaporation technique, however, they can be inefficient. This blog will explore the drawbacks of these evaporators, comparing them with rotary evaporators.

How do Falling Film Evaporators Work?

In most applications, the heating medium is on the outside of the tubes. High heat transfer coefficients are necessary to accomplish equally balanced heat transfer resistances. As such, the most commonly used heating medium is condensing steam.

When fluids are internally evaporating, separation across the liquid phase (the solution) and the gaseous phase happens within the tubes. To uphold conservation of mass as this falls, the downward vapor velocity rises and this increases the force acting on the liquid film and thus the velocity of the solution.

On the evaporating side of the tube, the heat transfer coefficient is often subject to the hydrodynamic flow conditions of the film.

Unfortunately, the inner wall of the heat exchange tube of the falling film evaporators must be entirely wet and the membrane is not too thick. It is important to implement a precise design calculation of the material feed and the length of the heat exchange tube in order to meet the requirements.

Additionally, the cost of falling film evaporators are extremely high as there are high design and manufacturing requirements. The rotary evaporator from Ecodyst does not use expensive rotary evaporator mechanisms, meaning they are an extremely cost-effective method of evaporation.

Read More: The Hidden Cost of Falling Film Evaporators

Falling film evaporators should also not be used for materials that are prone to fouling or are made up of solid suspended matter. Conversely, the rotary evaporator from Ecodyst can efficiently and gently remove solvents a broad range of sample types, this includes both organic and inorganic analytes as well as polymeric materials.

Falling film evaporators are often used in heat-sensitive products such as milk, fruit juice and pharmaceuticals as the time inside the heated tubes is very low and the materials are unlikely to spoil. Rotary evaporators also work well for these types of materials as samples are heated whilst the boiling points are decreased using a vacuum which is induced by the lab rotary evaporator. The boiling point decreases as the pressure of the liquid is decreased, and the solvent can be vaporized at a lower temperature than the standard boiling point.

Falling film evaporators are also extremely large, requiring a high headroom and meaning that labs need to mindful of how to accommodate them. As the Ecochyll from Ecodyst combines the chiller within the equipment, it has a much smaller footprint and can be used in even small-scale laboratories.

If you are looking to find out more about rotary evaporators and how they are superior to falling film evaporators, contact us today.