"Room-temperature fire?! Egads man, what's the point?"
The Tick
Scientists have created a new type of water... that isn't wet. Supposedly it's going to help fight fires without damaging fragile property -- like art and books -- but I'm not sure how it's going to work.
Water fights fire in two ways, and both depend on getting stuff wet. First, water has a high specific heat capacity, which means it can absorb a lot of energy and heat up only a little. When the water used to fight a fire heats up enough it will evaporate and carry the energy it has absorbed away, up into the air. Secondly, water helps douse a fire by engulfing it and restricting its access to oxygen.
Water that isn't "wet" won't stick to things and won't be where it needs to be to absorb heat and block oxygen. Fire is lighter than air and tends to move upward in a structure; water is heavier than air and moves downward. Regular water wets everything it passes as it moves down, but this "new and improved" pseudo-water won't be effective anywhere but at its initial point of delivery (if applied in a continuous stream) and at its final resting place where it pools.
Update:
Ray points to a New Scientist article that explains how the chemical works around my objections.
The fluid, produced by 3M, has weak molecular bonds and vapourises at just 49° Celsius, half the temperature at which water boils. It stops fires before they get out of control by soaking up heat from the nascent blaze.So it evaporates more quickly and absorbs less energy in doing so, which is a weakness and would indicate that the chemical can't fight fire as well as water can."This is a chemical agent that absorbs heat and vapourises better than water," says Joe Behnke, a manager at Tyco Fire & Security. According to 3M's web site, Novec 1230 requires 25 times less energy than water to evaporate.
The enclosed spaces are also necessary to corral the gas in the concentrations needed to extinguish a fire. Tyco launched its first fully engineered systems in January, but on Wednesday the company released new information about the system.The need for an enclosed space wasn't revealed in the original article, and this restriction changes everything. It sounds like the gas that results from the chemical's evaporation is a key component to its fire-fighting ability.
The chemical still sounds neat, and will likely be useful in some limited applications, but it won't be nearly as effective as plain old water for the vast majority of fire situations.
The first thing I thought when I read your blurb was: This reminds me of Ice 9 (quick, what's the reference).
Except this isn't "water", but a liquid chemical. My guess it has an extremely quick evaporation rate, so it doesn't damage books, but won't have the specific heat capacity of water, meaning you'll need more of it.
This is simply an engineering trade-off, except that it should be compared to halogen and other gas suppression systems that are used in depositories and computer areas and not water.
DM: I don't know, there are many details in the article. There are non-wetting liquids though, and this piece says that, not merely that it evaporates quickly.
It's a fluorinated ketone, according to New Scientist. Technovelgy.com also spotted the ice-9 connection.
Ray: Thanks for the pointer. It doesn't sound nearly as neat now, but will probably be useful for some limited applications.
I know this is digressing from the topic a little bit but I figured I might share this information in case anyone's interested based on personal experience working with the product. As mentioned above, Novec 1230 is made by 3M for use as a fire protection extinguishing agent - namely, a halon alternative. It is one of many chemical compounds that have excellent environmental properties when compared with other clean agents (ie. halon alternatives). As for price, this is negotiated with thier OEM's but you could easily guesstimate anywhere between $12-20 per pound depending upon quantity. At 13 lbs/gallon, it won't be cheap for the common home or even power computer user.
With that said, there are a number of other chemical compounds that would be appropriate for this application that might be a bit more reasonable. I have some personal contacts that work on the Research & Development side at 3M on products used for refridgeration/cooling and would be willing to help anyone interested on a particular application and is something that my firm is starting research on. In fact, the Crayes supercomputer is operated in a 3M di-electric cooling fluid....
As for experience with pumps, we have just completed two years of research pumping Novec 1230 and I can attest that flows beyond 50 gpm are possible provided the right choices in piping and pump selection are performed to compensate for the slight vapor pressure. With a SG=1.6, it's a 'bit' heavier than water but with dielectric strength up near 60 KV, contact with electronics is not an issue. Similar 'engineering' is necessary for the other non-fire protection products but pumping shouldn't be a problem for smaller flows as long as you can prevent cavitation.
CAPS Fire Inc. manufactures 'patent pending' pump technology used for the delivery of clean agents or halon alternatives used in fire protection systems and cylinder fill station operations and can be sourced globally. Clean agent pumps are available as components through all OEM’s and allow greater flexibility in system design.