Fuel Oils

Influence of the aging of middle distillates with alternative components on the functionality and assessment of additives according to No-Harm tests

To examine the effect of additives on fuel properties, as well as to identify possible interactions, the so-called no-harm tests can be applied. The DGMK published tests in their project 646-1, which can be used for the examination of additives in heating oil, and the AGQM developed criteria for additives for FAME in diesel fuels. In this project, the influence of different fuels and fuel types on the fulfilment of the no-harm criteria was tested for different additive types. Other examinations regarding stress tests on the fuels were conducted, in two different laboratory methods as well as in a test rig which mimics real conditions in a heating oil burner. Significant differences regarding the pass or fail of the different no-harm tests were found for the different fuels. Almost all the results of analyses for fuels with antioxidants were better than the corresponding sample without additive, however, increased amounts of sediments were found in the stress-tests. Flow and lubricity improvers showed less impact on the properties of fuels. During the runs of the test rig, sediments were found in several of the relevant components, but the amount decreased significantly in the samples where the antioxidant was used. All the results of the analyses conducted after the end of the test runs were better in the samples with the additive, compared to the sample without the additive. A simulation of refuelling processes showed no negative interactions between the additive and the autoxidation products. The additive fulfilled its purpose in the mixtures as well as in a fresh product.

The IGF project (17139 N) of the research association DGMK Deutsche Wissenschaftliche Gesellschaft für Erdöl, Erdgas und Kohle e.V., Überseering 40, 22297 Hamburg was funded by the Federal Ministry for Economic Affairs and Energy via the AiF within the framework of the programme for the promotion of joint industrial research (IGF) on the basis of a resolution of the German Bundestag.