A cooling management still is 1 of 3 different methods for the control of reflux within a distillation column. These include cooling management (CM), liquid management (LM), and vapor management (VM).
In this article, we’re going to explain how they work and if they are the best topology for your distilling needs.
What is a cooling management still?
A cooling management still uses a method of vapor extraction via the manipulation of cooling water to the reflux condenser. Within a cooling management system, the column is cooled before product takeoff. A portion of the vapor condenses and is sent back down the column as reflux.
By decreasing the water flow in the reflux condenser it causes the ratio of reflux to drop and increases output ABV. If there is an increase in cooling water, the ratio of reflux is increased. It is possible to create total reflux by increasing water flow to completely stop output.
The flow rate combined with the cooling temperature is controlled by a valve. This method allows operators to directly influence the proof of the finished distillate.
Components of a cooling management still
A cooling management still can be composed of various different components, which can include:
- Reflux condensers such as Dephlegmator or Coldfinger
- Product condenser such as shotgun or libig,
- Packed column of bubble plates
Cooling management is maintained by one of these components that brings cooling within the condenser of the column and causes reflux.
A valve is responsible for controlling the flow rate and cooling temperature.
The 2 common cooling management designs used are:
Water Jacket – A large pipe full of coolant water that flows around a slightly smaller pipe that carries vapor.
Shotgun Condenser – A large diameter pipe carrying coolant water, and multiple smaller diameter pipes carrying vapor run vertically through the larger pipe.
How does a cooling management still work?
There are 2 different styles of cooling management stills. The majority of distillers prefer to use the newer version of cooling management. However, both versions will be mentioned.
The original older style of cooling management stills features a design of cooling lines that travel throughout the column on the way to the product condenser. This design is less desirable because of the lack of flexibility with the product and the lack of consistency.
The newer style of cooling management stills features different components for the way of cooling. These components can include tubes, such as a dephlegmator, a coldfinger, cooling jacket, or a coil mounted inside the column. These methods allow for all of the reflux to be generated at the top of the column. To control the ratio of reflux, you will need to tweak the level of coolant flowing to the reflux condenser.
*NOTE* Coolant settings are not always consistent or predictable. On a hot day, the water supply will be warmer. During recirculation, the water will get warmer and will require constant attention.
IMPORTANT: The top of the reflux condenser should ALWAYS be open to the atmosphere to ensure no pressure is in the still. Alcohol cannot escape out the top if there is enough flow of coolant through the condenser. If the top of the reflux condenser is sealed, an explosion may occur.
What is a cooling management still good for making?
The original cooling management stills are only capable of producing either vodka or whiskey/rum. This is due to the design of the cooling tubes that run throughout the column and influence the amount of reflux occurring.
A newer design cooling management still is capable of producing potent and flavorful spirits such as vodka, whiskey, and rum. This is because of the more flexible options of cooling management and way of controlling reflux more consistently.
Advantages of a cooling management still
- A cooling management design allows for the production of some of the finest whiskey and rum.
- A cooling management still can feature various different components to optimize the ratio of reflux.
- Additional distillation cycles result in higher proof of alcohol and better separation of heads, hearts, and tails.
- With cooling management, it is possible to attain 100% total reflux.
Disadvantages of a cooling management still
- With an older original cooling management still, it can be difficult to maintain the reflux in the center of the column.
- Cooling management stills can be greatly affected by outside factors such as hot weather and storm fronts.
- A cooling management still often features outdated and less efficient methods in regards to distillation.
- A cooling management still can be inconsistent and unpredictable, requiring constant intervention.
What to consider if building a cooling management still
There are dozens of different stills that are created for the purpose of distillation. Each still has its own advantages, disadvantages, and specialties. If you are thinking about building a cooling management still it is important to consider these factors:
- Do you want to produce one type of alcohol or several variations of alcohol?
- Do you want to produce alcohol with flavors or no flavors?
- Do you have proper ventilation around the still and above the reflux condenser to the outside atmosphere?
- Does your distillation process require total reflux?
- Is the clean separation of heads, hearts, and tails important to you?
- Are constant adjustments and interventions important to you?
NOTE: When building a still for the distillation of alcohol, it is important to always research your local laws before commencing.
Frequently asked questions
Q1. What does CM stand for?
CM stands for Cooling Management.
Q2. Is a cooling management still easy to use?
The cooling management still is moderately easy to use and is one of the oldest designs around.
It is however more difficult than vapor management and liquid management styles, at with a CM still the reflux ratio is affected by the temperature and flow rate of the cooling water.
If your CM still is directly plumbed and for example, someone flushes the toilet in your house, the water pressure with drop, and your reflux ratio will change. This could even knock your still out of equilibrium!
Q3. Can you expect total reflux within a cooling management still?
Yes, but in reality probably not. You can expect to receive total reflux within a cooling management still if components are set to proper specifications.
In reality, though this would mean either a very large dephlegmator or a very high amount of cooling water. We find most distilleries operate with a small amount of leakage rather than overspecing to get complete reflux.
Q4. Is a cooling management still good for making flavored alcohol?
For the average hobbies, you are better running a pot still to make flavored alcohol.
Interestingly, commercial distilleries do often use large CM stills for making whiskies, rums and brandies, etc. They do this by detuning the still – by opening the plates and running with little to no reflux. This effectively turns the CM still into a pot still!