Cleaning out an old tank

[grien_machien Junior Member Find all posts View Profile Close grien_machien]

Hi all,

I have a 400litre fuel tank that was used for storing diesel (I believe). It was left neglected for years with the filler cap open. It was partly full of the worst smelling diesel/scunge I have encountered. Does anyone have any ideas on the best way to clean this tank for it to be suitable for storing B100?


Cheers,

GM

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Cleaning out an old tank

Presuming that you have reasonable access to the inside of the tank, using 20 litres of biodiesel, spray the insides of the tank, over a few days, at 4 - 6 hourly intervals to allow the biodiesel to work on the microbes. Drain the tank, filter the biodiesel and repeat the exercise a few times, or until the sludge stops coming out.
If the sludge stays put. or some is persistent, use a stiff broom to scrub those areas before repeating the exercise.
Filter and dry the biodiesel before using it in a (say 20% blend ) with clean new biodiesel, or just use the biodiesel to clean parts after this exercise.

I have not tried this on a large tank, but short of filling it with biodiesel, it is the best I can think of.

If you do not have good access, all I can think of is to lay the tank on one side at a time, and allow the biodiesel to flood that side. Repeat for each side and the bottom. If you can agitate the tank, do so, while the biodiesel works on that side. Pump out the biodiesel, and possibly use a pressure sprayer to work on the sludge in the tank. Drain out the water and sludge, and use some methylated spirits to dewater the tank. (after as much water as possible is removed.)
Biodiesel does clean out vehicle tanks, but there is a fair bit of sloshing in the tank, which may be impossible to replicate in a stationary, large tank.

[Robert Administrator Find all posts View Profile Close Robert]

Re: Cleaning out an old tank

Best way to clean dirty dino diesel sludge is with biodiesel
Biodiesel is an excellent natural solvent. I'd suggest swilling a few litres of B100 around it for a while. Repeat the process until you think the tank is clean.

Oh, looks like Tony posted a much better answer than mine only seconds ahead of my post - well in that case, what he said.

[Bill Biofuels Forum Newbie Find all posts View Profile Close Bill]

Re: Cleaning out an old tank

Biodiesel will also grow bugs. Those bugs grow on a fuel water interface. I suggest that after cleaning the petrodiesel deposits etc out of your tank, make it squeeky dry with dry alcohol (maybe isopropanol) and add some biocide to the biodiesel just to make sure.

[grien_machien Junior Member Find all posts View Profile Close grien_machien]

Re: Cleaning out an old tank

Some excellent suggestions, thankyou.

I have heard of people shaking nuts and bolts around in motorcycle tanks to knock off surface rust from inside the tank. I might try something like this also to remove the rust that surely must have built up in the tank.

I will update if I come up with any useful ideas.

Cheers,

GM

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Cleaning out an old tank

GM,
I was planning on suggesting something along those lines, but considered the B100 option to be a much easier first process. If you have any corrosion or other stubborn contaminants, you should consider nuts & bolts, blue metal (crushed rock >15mm mesh size) or other similarly sized sharp solids, placed in the tank and agitated vigorously to scour the inside surface of the tank. These must all be cleaned out of the tank once the process is complete, along with the contamination it removed.