"What is the best cleaning procedure for contaminated oil drums? We are starting a project for off-line purification of 80,000 liters of varnish-contaminated turbine oil. The oils arrive at our workplace in 55-gallon steel drums. The challenge is washing and cleaning dirty drums and filling them again with purified oil. Is there any standard procedure for cleaning tight-head drums, or should we dispose and replace them with new ones?"

There are several ways to address this situation, from the best practice of using a cleaned and properly sized container for housing and transporting the oil to the worst practice of rinsing and refilling the drum. All methods have pros and cons and will impact the reconditioned oil's life span. The worst thing to do is to recondition the turbine oil and then put it back into a drum that hasn't been properly cleaned. The same goes for putting new turbine oil into an already contaminated system. By doing so, the antioxidants will be attracted to these byproducts and be rendered useless before even being put into service.

Replacing each drum will save you time and energy. The process of cleaning an oil that has already led to a varnish problem can be labor-intensive and very time-consuming. Reconditioning used drums will not be easy, but it can be done. A number of systems on the market target varnish. The problem is that every drum will need to go through this cleaning process, which will take a significant amount of time.

Other factors that should play into your decision of which cleaning process to use include the type of failure that occurred within the lube oil, the type of varnish that is present and the equipment that is at your disposal. The process may be as simple as a wand flush using a filter cart or filtering the oil within the drum through an electrostatic process. Either way, it will be a slow process.

The best and most economical solution would be to use a larger container for transporting and cleaning. Larger containers allow you to filter the oil in the container while minimizing handling. This will eliminate the time involved transferring the oil from a 55-gallon drum to a larger container for filtering and reduce the environmental, health and safety risks. While this may not be the most cost-effective option at the front end of the project, it will yield considerable benefits in the long term.