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Join Date: Oct 2016
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Polyester Resin Polymerization

10/18/2016 9:56 AM

my question is concerning polyester resin polymerization in overflow traps from the infusion process used in wind turbine blade manufacturing. Information from the local landfill is that these block of resin would cause fires.

My first question is How long does this polymerization process last ex: days or hours ?

My next question is how much heat is generated during this phase Peak heat to end of this process ?

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#1

Re: Polyester resin polymerization

10/18/2016 11:11 AM

Maybe you could ask them to be more specific....

http://www.aoc-resins.com/images/uploads/K733%20Series_us.pdf

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#2

Re: Polyester resin polymerization

10/18/2016 1:33 PM

Maybe this paper will help.

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#3

Re: Polyester resin polymerization

10/18/2016 1:48 PM

The question above are about accumulated resin in resin traps approximately 18kg,

these are discarded but there is a residual polymerization that generates heat. I am inquiring in the level of heat and how long it last. I have a idea on how to use these discarded blocks since I was told that these would catch fire in landfills the heat could be harnessed but I need data to confirm its potential.

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#4
In reply to #3

Re: Polyester resin polymerization

10/18/2016 3:21 PM

The heat is generated from a chemical reaction that is a one shot deal....the shorter the period of reaction the higher the temperature...typical reactions last for maybe 7-15 minutes and peak temperature at 325-360°F with full catalyst saturation....So if you would calculate btu's and spread it over an extended time, you could approximate an answer...You might just take one of these 18kg lumps and put it in a tub of water, measure and record the temperature....Probably enough heat to make a nice bath....

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#5

Re: Polyester Resin Polymerization

10/18/2016 11:14 PM

Don't waste your time. These materials are hazardous and you are probably not qualified to work with them.

The duration of polymerization is far too complex to answer with "18 kg of resin in traps.

Start by studying " exothermic reactions in polyester resin".

I have experienced urethane foam exothermic reactions that melted HDPE mixing buckets, epoxies that caught fire and over catalyzed polyester that smoked, it was so hot. But none weeks later.

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#6

Re: Polyester Resin Polymerization

10/19/2016 12:13 AM

The rein once catylized will generate curing heat for many hours. After a week it is pretty much done but the resin may not be entirely hard as it can be. This takes weeks. In a landfill, the waste resin in the form of blocks or other waste gets attacked by the naturally occurring MEK and Acetone in the land fill. It breaks down the resin and teactivates the thermal reaction. This time around it has an endless supply of this set of solvents which continues to feed the ectothermic values. In the end it becomes a massive smoldering brick of intense heat that can start underground fires. To dispose of the resin waste it must be captured in a thick block of concrete at least one inch thick on all sides. The blocks must be scattered in different locations, within the compaction dirt layer that seals off the BENCH, or next level at the land fill.not as a group, just in case they were to rupture. Hope this helps. Mike W.

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#7
In reply to #6

Re: Polyester Resin Polymerization

10/19/2016 6:12 AM

Gotta be a way to use all of this waste energy.

Perhaps by concentrating it into one spot and using the heat to drive steam turbines,to help offset the operating costs of the landfill.

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#8
In reply to #6

Re: Polyester Resin Polymerization

10/19/2016 9:22 AM

I don't know that I agree with much that is said here.

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#19
In reply to #8

Re: Polyester Resin Polymerization

10/21/2016 1:01 PM

I don't either...If it's resin waste it would be classified toxic or hazardous, and not subject to landfill disposal...If it's fully catalyzed it's past any heat generation stage....Now if the blocks are being cut by the people at the landfill or the disposal crew , then there is a danger that some uncatalyzed material was trapped internally and now exposed would have the potential for chemical reaction....but with that knowledge precautions would or should be taken...The landfill operators may fear the crushing of the blocks would expose the possibility of fires, and quite rightly...If that is the case then the waste material is classified as hazardous/toxic and should be disposed of as such....

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#9

Re: Polyester Resin Polymerization

10/19/2016 9:29 AM

Sounds like another in a never ending list of products where proper disposal or recycle processing was never part of the plan before implementation.

I wonder if there is, or why is there not some type of law or regulation in place to prevent the manufacturer of any product without having a process to effectively deal with the manufacturing waste byproducts.

The idea presented to encase waste in concrete shells might seem like a good idea today, but what happens 50 years from now when all of those blocks are found in some long abandoned mine shaft, with half of them broken down, polluting the water table and no one knows how to deal with the mess.

Here is an example of putting the cart in front of the horse. Clearly windmills are being manufactured, you can't shutdown the assembly line. Is it possible that management, engineering or government oversight was lax in this enterprise.

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#11
In reply to #9

Re: Polyester Resin Polymerization

10/19/2016 12:58 PM

If the resin/catalyst ratio is correct and the proper stoichiometric balance is achieved, and the two parts are properly mixed the reaction should be complete.

This would leave little or no reactants for any further heat generation.

Stoichiometry - Wikipedia

The "wet lay-up" process is prone to generate a lot of excess resin and glass fiber (usually glass) that must be somehow discarded. Maybe chopping it to use as filler for another process is viable?

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#12
In reply to #11

Re: Polyester Resin Polymerization

10/19/2016 2:15 PM

That might work in some non-critical applications, however, in advanced airfoil construction as wind turbine parts, I would not think it wise to do that.

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#14
In reply to #12

Re: Polyester Resin Polymerization

10/19/2016 4:54 PM

You would not think it wise to do what?

If you mean use as a filler for another process, I meant like concrete filler.

Heavens no, not for use in turbine blade a lay-up.

A group of 10 co-workers helped one of our buddies pour a patio years ago. (1980)

Well the beer started flowing before the redi-mix truck even arrived.

He didn't order enough concrete, so the sound technical decision was made to chunk a bunch of rocks in to stretch the concrete.

When we were done, none of the rocks were exposed, yet.

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#16
In reply to #14

Re: Polyester Resin Polymerization

10/20/2016 1:35 PM

OK, I agree with your modified comments. I mainly meant only use virgin materials in the airfoils.

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#18
In reply to #16

Re: Polyester Resin Polymerization

10/21/2016 11:48 AM

Agreed. And the other elephant in the room is the glass/resin ratio.

The final product is mostly glass.

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#10

Re: Polyester Resin Polymerization

10/19/2016 10:44 AM

Answer No.1 : Do not send this to the landfill. Shred it and send it through one of those microwave plasma disintegrators, and recover the useful chemicals at the outlet, such as gases that can be used to power the disposal process plus excess power to the grid.

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#13

Re: Polyester Resin Polymerization

10/19/2016 4:29 PM

..." Typically, liquid resins and gel coats are chemically catalyzed immediately before application, and thus, have a limited useful product life. As the resin/gelcoat and catalyst mixture bonds together, the reaction eventually proceeds to a point where the mixture hardens into a solid that cannot be further processed or utilized. These nonhazardous, solid wastes are typically disposed of in offsite industrial landfills"...

The resins are toxic before catalyzation, but after hardening are no different than regular fiberglass, they are landfill unless you can find a way to recycle them....

https://www.pca.state.mn.us/sites/default/files/4_50.pdf

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#15
In reply to #13

Re: Polyester Resin Polymerization

10/20/2016 12:44 PM
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#17
In reply to #15

Re: Polyester Resin Polymerization

10/21/2016 10:49 AM
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