I have 300 gallon tank formerly filled with gas oil / 35 sec heating oil / medium diesel (not sure of the U.S. terminology). The only way I can remove it is by first cutting it up. Any suggestions / comments so as to do this safely?
Depends on how far away it is from valuable things like houses and such. How about pouring in about a quart of gasoline, let it sit in the sun for a few hours then toss in an M-80. It'll be real easy to cut up the big pieces. There are people on this NG that are figuring exactly how much gasoline, at what temp and how long to wait. Other people are figuring how to add servo motors and PLCs. There's no wrong way to blow it up! Somehow this will turn into a political issue and it'll be Bush's fault, or..."Hold my beer and watch THIS!"
Cutting up a heating oil tank is relatively easy and safe since heating oil / #2 diesel fuel isn't particularly volatile, however that is not the issue. The issue you will have is disposing of the oil coated metal pieces and worse yet the thick layer of sludge that is invariably on the bottom of the tank. The US had less stringent regulations on suck stuff than the UK and even here it's generally not worth the trouble of trying to remove and dispose of a heating oil tank yourself. It can be done, but if you attach any value to your time it's cheaper to have a properly equipped and insured company do it.
Fill it full of water. Introduce an oxidizer and let it rust. Back fill with dirt as necessary. Should not take more than a few years. And not much effort needed. If you get bored you can pull up a chair or old couch and have some beers while you wait.
Rob, years back I used to monitor the removal of gas and oil tanks in CA. Weren't allowed to use any steel tools (not even wrenches) due to spark danger. Everything had to be brass or equivalent non-sparking. Reg's required us to dump dry ice into the tank to displace the volatile stuff. After 3-4 hours we would finally get low enough readings with an electronic detector (sniffer) to allow tank removal and off-haul to a metal recycler.
NOTE: There are many documented cases of recyclers being blown to bits from cutting into tanks delivered as above. Reason? They would wait weeks or months to cut into the tank by which time the tank is again full of volatiles that came from the greasy insides. These tanks were all completely empty but for a tiny bit of product along with greasy, oily sides.
DO NOT cut into the tank with anything that is metal (saws-all etc.) unless you very recently have displaced the formed gases with either dry ice, water, or whatever you have that is heavier than the explosives.
Tried that when I was a teenager on a smaller scale. End of summer in Louisiana, five gallon container with lid. Used cotten cord soaked with saltpeter for fuse which went thru small hole in the cap. Small amount of gasolene, maybe a pint.
Anyway friends and I took it down by the bayou, parked the car ready to get out of there. Lite a match and brought it over the cap to get to the end of the fuse. And instantly had a small flame about two inches high from the fumes leaking around the fuse.
Thought OS, and then saw that a police car was coming down the dirt road that was the only way back to pavement.
Eventually while the police were lecturing on the dangers of gasolene, I took a clod of dirt and extinguished the flame.
The gasolene vapors had driven out all the air in the time between when we had put the gasolene in and when we had gotten out by the bayou.
The police took the names we gave them and let us go on our way. I forget the names we gave them.
I did an old cylindrical 350 gallon tank under an enclosed porch. Local companies wanted $1000+ 2$/gallon to dispose of the old oil. The only opening in the block wall to the tank was much smaller than the tank. The tank had ~ 250 gallons of 30+ year old fuel oil in it. I pumped it into drums with a air driven diaphragm pump and gave it to a local garage with a waste oil heater. He was glad to get it. I purged the tank with Nitrogen, but was still nervous, so I broke up 5 lbs of dry ice and dropped it into the tank, the vent was still connected and I was was getting a good flow of CO2 out of the vent when I started cutting it up with the Sawzall. Took about an hour to reduce the size to chunks small enough to remove through the small doorway. The wall thickness on this old tank was pretty heavy, and I was pleased to see after scraping the inch or so amount of sludge out of the bottom none of the corrosion went through the bottom of the tank which was resting on bare soil. Total weight at the scrap yard was an amazing 800 lbs. which more than paid for the Sawsall blades.
My first involvement in conversion of navigational aids to solid state in the mid '70s, we would pump out the underground diesel fuel tank and fill it with sand. By 1990, the tank had to be removed and the soil underneath hauled to a hazardous material handling facility until all traces of contamination were removed. At one point I did a survey of airports to list all underground fuel tanks. One former military field had at least two tanks at each hangar
- some still in use after 40+ years and just inside the former Base main gate, a storage tank for gasoline which was sold to civilian employees (gas was rationed during WWII and civilian staff were allowed to buy on base but couldn't drive on base unless they had car insurance, which most did not). In this case, all evidence of the fueling facility had been removed for grounds maintenance but the tank was still there. I had stumbled on it's existence through review of old base records. Another case involved an abandoned fuel tank buried under an interior courtyard with no access for excavation equipment. Gerry :-)} London, Canada
"Rob" wrote in message news:Rw88m.11571$ firstname.lastname@example.org...
following this thread with interest. i had heard of someone who hand dug around a 1000 gallon tank, was in the ground since the 70's. was too heavy to pick up with a compact tractor so he plugged the tank and filled the trench with water and floated the tank up and rolled it out of the trench, he felt clever and was proud. after getting it out he cut a 2' x 2' square hole in one end with a bosch jigsaw and scooped out the inch or so (on the low end of the tank) of sludge. he said he was amazed there was only *slight* pitting at the bottom of the tank so it was obvious there couldn't've been any oil leaking at all, the tank was in good/excellent condition but the fear of a leak precipitated it's removal. the empty pit was entirely oil free, thank goodness. tank was made of (surprisingly) 3/16" thick plate. cut it up the rest of the way with a plasma cutter. no fire/smoke problem at all. second tank he cut up was dragged out of the woods from an abandoned farmer's road. 275 gal. tank had obviously been sitting there for like
15/20 years. actually had tiny holes rusted through in a couple spots. sniffing inside BARELY smelled at all of oil. figured it was safe to start cutting with the plasma and forego the hassle of starting with the sawzall/jigsaw. this person wasn't aware of the dry ice trick and was too cheap to go get a bottle of CO2, figured he'd chance it. figured whatever traces of fuel oil vapors that remained weren't volatile enough to ignite. there were mice nests inside the tank and when plasma cutting the tank the mouse nests started to smoke. was kinda scary because the smoke was like a funky green or brown color. he was worried there might be enough volatile material in the funky colored smoke to ignite, and there was great fear it might ignite explosively. scariest part was when he was spraying water into the open bung holes of the tank it actually seemed if the smoke increased! it didn't start to subside for a WHILE. there was a increasing fear that there might've been something in the tank other than old evaporated fuel oil. he attests it was really quite terrifying. i think he was very lucky that time(!). after cutting this tank had no sludge but organic (weeds, grass, straw) mouse nest materials (and two oil mummified mice). recently there was wondering if it would be possible to get a small (80cu.ft) tank of CO2 and empty the CO2 gas into a 275 gal. fuel oil tank to safely cut it up. now there is wondering how many pounds of dry ice would be enough to make enough CO2 gas to fill a 275 oil tank to safely cut it up. this person doesn't have the electronic sniffer tool mentioned in a post to this thread. there was something recently on-line about a local tank removal company writing they "inert" an 1000 gallon tank and then there were still photos of an access hole being cut with a demolition saw w/ abrasive wheel. the person cut the tank in half, lengthwise, and then trimmed the two halves so they could be used as a large "tray" or "scoop" on the forks of a "forklift" thingy on the three point hitch on back of a compact farm tractor. turns out they're really quite useful for hauling rocks (full bucket in front and a "full" tray on the rear). and hauling firewood from the area where his log splitter is to the woodshed, a 275 gal. fuel oil tank cut lengthwise holds more than the front bucket of a compact farm tractor, easier, less trips. i think the steel "tray" is possibly even lighter than if it were to be built of wood.
No, purge the tank with low-pressure Oxygen (with an 1/8" or so purge hole at the other end), then add in about 25 to 50% Acetylene by remote control and stay under 15 PSI at all times.
Concentration isn't critical, IIRC the LEL of Acetylene is anywhere from 4% to 96%, but there will be a sweet spot for max energy release.
Then pull a long string to close the purge valve, then activate your spark plug from the other side of the ridge and a good half-mile away. Be wearing earmuffs over earplugs.
HUGE Boom. Probably rank right up there with "Jamie's Disappearing Cement Truck".
You don't want to be in Line Of Sight of that fuel tank when you detonate it unless you are standing behind something really stout, that shrapnel is going to be /moving./ And I'm sure there are even more energetic fuel and oxidizer combinations out there you could use, but you don't want them too sensitive to where it blows before you are ready. Oh, and consider that some of the nicer ingredients are a wee bit hard to get, especially after 9/11/01