Industrial Nitrator

[stanfield]

Anyone got a picture, photo, schema,... of an industrial nitrator ? I browsed google but found nothing interesting...

thanx !

[Eliteforum]

<img src="http://www.nobel.se/nobel/alfred-nobel/industrial/krummel/krummel6.gif" alt=" - " />

This what you looking for?

<a href="http://www.nobel.se/nobel/alfred-nobel/industrial/krummel/" target="_blank">http://www.nobel.se/nobel/alfred-nobel/industrial/krummel/</a>

[stanfield]

yeah, this is the (only) picture I've found on google. But this one is only for nitro and outdated, no ? what about a modern nitrator ? is this the same "schema" ?

thanx !

[stanfield]

futhermore, the cooling is assumed by water if I well understood the picture ? I never though nitration of nitroglycerin could only be cooled by water ! :) this nitrator mustn't be very reliable !

see ya !

[nbk2000]

It's usually not plain water, but rather refrigerated brine (water salted to allow cooling below 32*F without freezing).

[stanfield]

I think so !
nowaday, this may be liquid nitrogen, no ?

[rikkitikkitavi]

For pictures of reactors, I recommend any good book about chemical engineering, prefereably about reactor design. The picture is very typical.

Nitration is chemical engineeringwise not different from other exothermic reactions. You just have to have a very tight controll over reaction parameters like temperature, NOx evolving e t c or whatever you use as a signal to dump the nitration mixture into water. Or someother method of quenching it.

Most nitrations are made in batchreactors for obvious safety reasons. It is easier to controll them that way. And dumping is easier. You also have a limited amount incase of runaway.

When we add A+ B + C during stirring in a glass bowl and preciptate D and filter it of it is a perfect exampel of a batch process.

Only your imagination can tell how the reactor will look like. But the picture is very typical. Except from the missing dumping valve in the bottom (or sometimes in a large vessel above to flood it)

you can cool it with whatever you want as long as the cooling coil and cooling jacket is large enough to remove all the heat while keeping temperature down.

As NBK2000 pointed out, some sort of freezing point depressant is usually used as a coolant at sub-zero(Celcius) so that the apparatus can be compact bu yet a high heat transfer (high output).

heat transfer is proportional to tempdifference, area and heat transfer coefficient, which is a variable dependand on how vigourosly the nitration mixture is stirred...
And the hgiher the heat transfer the faster you can do your nitration and the more tonnes you can squezze out if your equipment.

Some reactors are stirred by pressurized air, like a jacuzzi.

Gas phase nitration of alkanes to nitroalkanes are made continiously in tube reactors. I have read about a similar method of NG-production where the niter acid was pumped into a tube in which you pumped glycerine aswell.

/rickard

<small>[ December 03, 2002, 02:01 PM: Message edited by: rikkitikkitavi ]</small>

[VX]

I wouldn't have thought that there is any need to use liquid Nitrogen. There is several ways to slow the reaction down to prevent excessive heat build up in the first place, ensuring a slow addition of reactants for example.

Although using liquid nitrogen would cool the vessel down faster, it would be inefficient as far as cost goes. Although NG could be made faster this way it would not compensate for the extra cost of liquid nitrogen. These 'compromises' are extremely common in industry.

In addition the whole manufacturing process will be computer controlled, always ensuring that reaction conditions are kept within very fine optimal limits. Such computer controlled processes would make it possible to make NG (for example) without using any cooling system at all, although it would take far longer to make a set amount of product as if a coolant system were used, as the reactants would be added VERY slowly to prevent heat build up.

Edit: rikkitikkitavi beat me to it. I mustn't type fast enough.

<small>[ December 03, 2002, 10:34 PM: Message edited by: VX ]</small>