Sciencemadness Discussion Board

Weeping Dynamite (syneresis)

Bender84 - 11-3-2017 at 11:52

Hello World,

I try to find information about possible ways/ procedures to deal with weeping dynamite. Recently we experienced a problem with our product due to poor homogenization and gelatinization of the mixture. We think it was caused most probably by a major temperature fluctuations (it became very cold within few hours which affected the gelatinization process). Whatever the cause, the dynamite started to weep.

Of course we have internal procedures to deal with such situations, but I was wondering if anyone of you knows other solutions for such issue. The standard procedure is to absorb the spilled NG with an inert material (e.g. wood meal) and then burn it. In case of spillage we wash the place with a base solution.

I would like to ask You two questions:

1. Are there any alternative (and safe) processes to deal with the spillage (small quantities of NG in the bags with faulty product) ? I read about a mixture of triethylene glycol, acetone and hydrogen peroxide (it was called NG killer) but when I asked my collegues about this idea, nobody had a clue.

2. Does anyone have any data about the kinetic of the NG neutralization process with the base solution? i.e. how quick it is/ how long will it take to render the spilled NG non-explosive?

Kind regards

Chemetix - 11-3-2017 at 13:01

Are you working at a commercial explosives manufacturing facility? The wording of your message makes it sound that way. I for one, am slightly horrified at the prospect of a site working with NG that needs a public forum to deal with batch defects and reformulation.

And you don't specify what kind of dynamite, there are so many specific formulas of dynamite that have their own inherent physical and chemical properties.

Bender84 - 11-3-2017 at 13:22

Yes, I work at a commercial explosives manufacturing plant. I have said that we DO HAVE procedures do deal with such issues. I'm just curious if there are any other not so common solutions to this type of problems, i.e. other than mentioned and well accepted absorbtion of NG in an inert material and burning it and washing the place with base solution.

As for the type of explosive, we produce gelatinous dynamite. That is why I mentioned syneresis in the topic. Obviously I cannot give you the exact formulation but the largest part of the product is ammonium nitrate ( >50%) and there is about 20 - 35% of blasting gelatine, depending on the formulation. The rest are other functional additives (fuel, plasticizer, stabilizers, etc.).

[Edited on 11-3-2017 by Bender84]

Chemetix - 11-3-2017 at 14:02

I was trained to use the standard neutralising solution of water and bi-carb soda when dealing with weeping dynamite, ammonium nitrate needs to be dissolved and washed away from the nitro ester component as much as possible and neutralise acid residue. Then absorb absorb absorb; I've heard of camphor and acetone being used to to make a waxy residue with the NG that allegedly made it safer to handle. But I think they were talking about straight dynamites not a gel with NC.

Once you are away from standard procedures that haven't been validated for the particular application, you're on your own really.

Bender84 - 11-3-2017 at 15:22

@Chemetix

Thank you!

May I ask if you have any knowledge about the kinetic of this process (neutralisation with water/bi-carb soda solution)? I'm asking this because we assume that the operation should take 24 hrs to completly render the NG harmless but to be honest, I couldn't find any data in our lab (and in the literature) to justify this statement. I have been told that it is just good practice based on the experience and I would like to take a look at the science behind it.

PHILOU Zrealone - 11-3-2017 at 19:41

Quote: Originally posted by Bender84  
@Chemetix

Thank you!

May I ask if you have any knowledge about the kinetic of this process (neutralisation with water/bi-carb soda solution)? I'm asking this because we assume that the operation should take 24 hrs to completly render the NG harmless but to be honest, I couldn't find any data in our lab (and in the literature) to justify this statement. I have been told that it is just good practice based on the experience and I would like to take a look at the science behind it.

It is just an hydrolytic reaction of an ester (can be easily followed with a pH meter if base in stoechiometric amount (3 moles/mole NG)...
--> the stonger the base into water solution, the faster it is so better use NaOH or eventually Na2CO3 than NaHCO3.
--> the better the homogeneisation (use of anionic soaps will do wonders), the better
--> the higher the temperature the best (but with NG better stay below 50°C)...
Usually then the hydrolysis of ester is acheived in less than an hour (even in 15 minutes).

Bender84 - 12-3-2017 at 02:09

@PHILOU Zrealone

Thanks!