Additive Evaluation in Venezuelan Diesel Formulations 1999-01-1480
Six commercial different additive packages to be used in the Venezuelan Internal Market Diesel formulations were evaluated in terms of their performance in corrosion inhibition, oxidation stability, injector cleanliness and emissions, as well as fuel economy improvement. Laboratory, field and bench tests were carried out. In laboratory tests, additives evaluated were added to four Venezuelan Diesel fuel formulations at the recommended supplier doses: corrosion (ASTM D665), oxidation stability (ASTM D2274), emulsification (ASTM D1094). Also, physicochemical properties required by Venezuelan Diesel fuel specifications were evaluated. Three different trucks (per additive) were run in fleet tests in order to determine injector cleanliness performance. Truck injector flow was measured in every injector, according to ISO 4010 procedure, before and after 5000-6000 km field accumulations. Two trucks were run without additive dosification, and were used for base line comparison. Injectors fouled (dirtied) from field and bench tests were cleaned up by detergent additive dosification in Diesel used in bench tests at four different loads and driving conditions. Emissions such as HC, NOx, CO, particulate (PM), and fuel economy tests were measured before and after injectors were cleaned. Laboratory results obtained show that all additive packages improved corrosion and oxidation stability. NACE scale A grade in corrosion inhibition was obtained in all samples evaluated, and a sediment reduction was observed between 60 and 90%. Three different performances in field test were observed: two additives cleaned more than 90% of injectors evaluated, other two cleaned around 56%, and the others only around 12% of total injectors evaluated. Bench tests showed that emissions were reduced between 13-24%(HC), 6-10%(CO) and 2-12% (PM) in two sets of six injectors evaluated. NOx increased around 2-3%. Fuel economy was improved around 0.5-1.0%, when injectors were cleaned by detergent additive.