This may be a little on the unusual side, but that’s a part of my new estimating position here. I need to locate what I believe would be a Thermodynamic Engineer or someone who could help with my issue.
Cliff notes:
We will be producing components of exhibits for a battle tank museum in Massachusetts in the spring. One of our tasks is to provide somewhere in the neighborhood of 300 tons of various quantities of aggregates (soil, sand, crushed concrete, and stone) which will be placed around the various tanks based on their era and / or particular battle. The most efficient way I can figure to logistically handle this is to supply all materials from local Massachusetts vendors / suppliers. Here’s the catch.
Our exhibit materials must be free from insects and microorganisms so we need to cook everything in an oven to a certain temp for a certain time. I’ve located a lumber yard with a kiln who will do the cooking. Problem is, he’s never done this and there’s one variable he doesn’t have data for. Time.
We are going to handle and transport materials in 3x3x3 bulk bags (holding approx. 1 cu.yd. of material). That being said, we need to know roughly how long it would take to heat each material so that the center or “core” of the bag would reach the desired temperature. Once that temp is reached we know how long we need in the kiln.
I’ve had no luck finding any data for this on line, as I doubt anyone would ever bother to work up figures for something like this. If anyone can help, or point me in the right direction, I would be eternally grateful. This is a paying gig if need be. Only other option would be to experiment with actual materials in their kiln, and we’d like to avoid that if at all possible. Thanks.
I think the toughest part of this is the fact that you’re looking to sterilize organic material without changing the composition. Stone and whatnot would be easier but the soil is the tough part due to the low combustion point of most organics.
I would say that before you start looking into the math/science route, I would reach out to any existing museums or science centers that have similar exhibits and see what they used. Instead of baking, maybe a there is a chemical spray that kills everything.
The crushed concrete and stone will be easy as there is 0/negligible water content. Your sand and soil will be a nightmare to replicate from batch to batch.
Most heat treatment applications I’ve been involved in require thermal recording. This can be done fairly easily/cheaply.
For under $1000 you could provide a chart with each batch. Youll easily save money versus paying someone for the calcs and for overrunning material in the kiln.
I thought about that too, as well as “zapping” it with microwaves, gamma rays, or cosmic rays. Not sure how they will feel about introducing chemicals into the idea.
I would go for a conveyor to transfer the material into the bags. Use ultraviolet light over the conveyor.
A quick look shows semi wet soil to have a specific heart of.25 btu/ lb. 300tons * 2000 lb/ton *.25 btu/lb = 150,000 btu per degree. If you take it from 50° to 200° multiply that by 150 to get an idea of the total energy required. Time will depend on the surface area, batch size and temperature of the kiln.
It’s not about the drying, it’s about the “living organisms” we can’t import into the building. Artificial interiors have been done before but it’s not what the boss wants. Boss gets what he wants.
Model trains are a little different. We’re talking about full size tanks with exhibits people can just about walk on. This may have to be done locally anyway. If I can’t get an aggregate supplier on board up there, even though I’ve told them to charge just about whatever they like, the whole exercise is kinda pointless. I’ll have to do real world testing with the local guys and just truck it all up there.
Appreciate the help. This is probably going to end up happening local and trucking up there. Seemed like the harder choice at first but may end being the best way.
