EFFECTIVE BURIED TANK INACTIVATION
Traditionally, buried tanks are rendered inert with sand or concrete, except when these tanks are “temporarily” set off filling them with water.
Water mixes with the residual waste and the mud, forming a dangerous substance that requires treatment when retired.
The mixture with water in a tank during a long period of time increases corrosion and is a continuous environmental risk.
It is almost impossible to fill completely a tank with sand.
There are always empty spaces and corners..
Filling a tank with sand is very expensive. Not only sand must be transported, but the pipes must be taken off and also the manhole cover must be removed. A 10.000 l. tank filled with sand weights about 17 tons. In case of removing sand, it must be considered as a dangerous substance.
The weight of a concrete filled tank is a serious problem. A 10.000 l. filled with concrete weights about 27 tons. The concrete filling process is particularly difficult and expensive when the tank is placed in urban zones, under the building foundations, warehouses, parkings, garages, etc… Unbury a concrete rendered inert tank, is a very expensive work. Four or five solid concrete blocks under the ground, seriously harm the goods value.
La espuma para la inertización efectiva de tanques enterrados es una resina de la familia de los aminoplásticos.
Foam to effectively render inert buried tanks, is a resin of the amino plastics family.
The main advantage of this white foam is its ability to rapidly absorb different high specific weight substances.
This foam not only absorbs the whole hydrocarbons gamma, but also substances such as acetone, benzene, tricloroetilene, fluoro-benzene, alcohol-isobutyl….
The incrusted waste in the tank walls, is absorbed and fixed by the foam during the injection, what terminates all environmental risks.
Foam will absorb all the spilled hydrocarbons in case of a leak in the tank. Once the foam hardens, it goes over a lasting and stable state.
The hydrophobic inertization foam is recommended and applied in many different European countries as Holland, Germany, Belgium, France and England.
Thanks to a clean and fast application method, this foam is specifically appropriate to render inert subterranean tanks in urban zones, in buildings, car parkings, warehouses, garages, etc…
As well as to render inert buried tanks and pipes, the foam is also used to inactivate sewers and ground cavities.
A particular application of the foam is to absorb hydrocarbons poured out in rivers and channels.
application of the foam does not require any specific precautionary measure, except the common hygiene and safety procedures stated for working in fuel storage tanks.
So, it is not necessary to switch off any pipe or dismantle the manhole cover. It is only required a 2” opening to introduce the injector flexible hose.
Also, it is not necessary venting or clearing the tank. Air and vapours are evacuated trough the venting pipe.
The resin is mixed with a hardening product in the injector mixing chamber, in 7 bar pressure, and directly injected in the tank.
The foam expands and fills the tank completely without leaving any empty space. Once the tank is full of foam, the openings and the manhole are filled with foam.
- The foam is not toxic.
- Foam fills completely the tank, and no empty space remains
- The injector only needs a 2” opening and another one for the venting pipe. It is not necessary to dismantle pipes and the manhole cover.
- The injection is a fast, safe and very efficient process. The injection speed is 18 m3 per hour on each injector.
- Foam once it hardens, stays lasting and stable. The expected lasting of the foam is more than 150 years.
- Foam only weights 25 kg per 1.000 l.
- Removing foam from the tank is not a problem.
- Foam is environmentally stable.
- The use of an inhibitor in the foam, protects the tank walls from corrossion.
- Foam fulfills Rule IS 0844 and once it hardens, has a compression resistance of 230 k Pa/cm3.
- Foam resists high temperatures until 220ºC.
- Foam application is fase, clean and easy under any climatic condition. The risk of heavy weight trafficis terminated.
- A tank full of foam can be unburied and store don the floor, without any risk due to the vapours accumulation inside the tank.
- It is not toxic.
- It has a very easy appliance as well as around the tank as under it in a 200 to 500 mm layer. Application does not has a time schedule as cement mixers. The fast hardening allows to put the upper cover or the final concrete layer on the next 12 or 24 hours, depending on the outer temperature.
- The application of the foam is fast, easy and safe. It is possible to produce 18 m3 per hour of foam per injector.
- The foam has a high isolating power (thermal conductivity is 0,027 W/mK on a 25º C temperature) minimizing the temperature fall of the product after a delivery.
- A 200 mm foam layer around the tank is enough to assure that the product temperature won’t fall in more than 1º C in 7 days. If the layer is 500 mm, temperature variation extends to 14 days
- Foam, once it hardens, has a compression resistance of 300kPa/cm2. The imposed loads are transferred to the basis, without affecting the tank.
- Foam, once it hardens weights 30kg/m3. Foam is very easy to remove. Non contaminated foam is biodegradable by photosynthesis and if it is contaminated it can be packed and burned, where it is allowed..
- Foam absorbs and retains all hydrocarbons until an 80% of its volume.
This foam is a very interesting substitute of sand, as filling of the covertures of the simple wall tanks.
In case of an accidental overload of the tank or leak, foam can absorb hydrocarbons, protecting the waterproof of the bunded areas, preventing an environmental contamination, Foam can be easily removed and its treatment is less expensive than sand.
Our hardening foam for buried tanks filling is an amino plastic polymer chemically hardened, produced and applied in an watery environment.
This foam, without any solvent, is environmental and its special chemical and mechanical properties make it very suitable to fill buried tanks, as well as steel, polyester or fibreglass made tanks.
Foam has a hardening time of from 5 to 30 seconds, since it comes out from the injection nozzle. Once it hardens it is rigid and cohesive, holding firmly the tank, but without adhere to it.
The accelerated aging tests indicate thet there is no alteration of the material in a projected period of 150 years and in a temperature gamma of from -198 to +100º C. Foam does not burn but carbonize at temperature higher than 300º C.
Foam can be eliminated, with simple hand tools. Once eliminated, non contaminated foam is degradable by photosynthesis, reverting in nitrogen. If the foam is contaminated it can be packed and burned, where it is allowed.