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Water-Related Posters

Water-Related Presentations

Waterless Condensers

In many instances, waterless condensers can be used instead of traditional water-based condensers for synthesis reactions in chemistry. The exception is for low-boiling solvents.....waterless condensers don't work well for these. Waterless condensers help laboratories conserve water, protect labs and their assets from flooding that can be caused by a disconnected tube during water-cooled synthesis, and are easier to set up than a condenser that utilizes water. See two examples of waterless condensers below that your lab could try. CU Green Labs has offered free waterless condensers of various sizes to labs in the past to try. Reach out to CU Green Labs to see if we have any available!

Asynt Glass Waterless Condenser                                                               Findenser

Product Information                                                                                                            Product Information 

Asynt glass condenser                                                     Findenser waterless condenser for chemical synthesis


Water Purification

If your laboratory has access to a water purification system (there are many different kinds), be sure to ask yourself and/or your lab mates about whether purified water is required for your lab procedure or application. It might not be needed at all times. It is important not to default to using hyper-pure water because it is energy and water intensive to make that water. Types of purified water utilized in labs are: distilled, reverse osmosis, ultrafiltration, and more.

Here are a few references to help you assess water purification practices in your laboratory:


Water Misers for Autoclaves

picture of two autoclavesAutoclaves are large water consumers. Without a water miser, an autoclave can consume 45-50 gallons of water per minute, 24 hours a day, 7 days a week. On non-retrofitted autoclaves, cold single-use tap water is continuously sent down the drain below an autoclave just in case the hot condensate from the autoclave is flushed down the drain too. The purpose of the tap water is to cool the condensate.

A water miser is a tank with a temperature probe retrofitted to an autoclave. Hot condensate is flushed from the autoclave into the water miser and then mixed with cold tap water to bring the overall temperature of the mixture low enough to be safely released down the drain. A water miser prevents the continuous flow of cold water down the drain, resulting in up to a 99% reduction in water use. 

Most autoclaves at CU Boulder are retrofitted with water misers to conserve water. If you hear the sound of draining water from your autoclave, even when the autoclave is off, contact Facilities Management to make sure your water miser is still working properly, helping our campus conserve our precious water resources.





recirculator that uses building processed chilled water inside a fume hood

Use Processed Chilled Water (PCW)

Some buildings on the CU Boulder campus have a Processed Chilled Water (PCW) system, which is a byproduct of the building's heating and cooling system. PCW is a closed-loop system, and the water within the system is pumped around the building and maintains a fairly stable water temperature. PCW can be utilized for research to cool various pieces of equipment and reactions if the required connections to the PCW system are available. For example, some fume hoods have PCW hook-ups. Keep in mind that a building's PCW system is under high pressure, so the right equipment is needed in order to access this water source. In addition, no water can be removed from the PCW system, so any connection to it must be an output with an input.

Below is a photo of a recirculator system called an eVap that is connected to the PCW in JSCBB and used to cool a standard water-cooled synthesis reaction inside a fume hood. The eVap device provides cooled recirculated water to a condenser (or multiple condensers) by using a heat exchanger and the building's PCW. This saves water and reduces the risk of flooding in the lab.

If you'd like to explore using PCW in your lab, contact CU Green Labs!






Low Flow Aerators for Lab Sinks

lab sinkDoes the water from your lab's sink come out too quickly, splashing inside the basin and splashing the objects surrounding the sink? Perhaps you need to reduce your water flow! This can save significant water for laboratories, and is beneficial for scientists too because there is less splashing of glassware or other items drying next to the sink.

Reducing the flow of water from your sink can be done with a low flow aerator, which is affixed to the faucet of your sink. These reduce water flow to 1 or 1.5 gallons per minute instead of 2 or 3 gallons per minute. Use of a low flow aerator on a splashy sink can reduce water consumption by 50%! If you have a sink that splashes, contact CU Green Labs to see if a low flow aerator might work for your lab.