Assessing the performance of oil interceptors at fuel service stations in Kampala.

Abstract

Globally, there has been an increase in the number of cars, which has led to an increase in the number of fuel service stations, especially in Uganda and a question arises as to whether these service stations have all the necessary requirements in place for example the oil interceptors, as mandated by regulatory bodies like the National Environment Management Authority, NEMA, therefore there is need to diversify knowledge and understanding on the use and performance of oil interceptors constructed at these stations. This research investigated and took an in depth look at some of the factors that affect the performance of oil interceptors at fuel service stations for example the number of cars serviced at the fuel service stations, the influent and effluent characteristics, type of construction, the covers used, the types of pipes used and presence of mud traps, the cleaning frequency and length to breadth ratio of the oil interceptors. Thirty branches of the main fuel service stations, Shell and Total, within Kampala district were taken into account, selecting at least one from each of Kampala’s divisions and choosing fifteen for both Shell and Total stations. All the thirty fuel service stations were found to have been constructed with oil interceptors as mandated by NEMA and the research showed that Total fuel service stations serviced 67% cars, higher than Shell which services 33%, 43% of the stations had Type A of interceptor construction and slab covers compared to the 57% of stations that had the Type B and grating covers. In regards to l: b ratio, 27% of the stations were above the mandated standard and 73% were below standard, and the stations with Type B construction, grating covers and l: b ratio below standard, had high concentrations of FOG, TDS, TSS, COD and other parameters in their effluent. From the analysis summarized above, the study recommends the use of Type A construction, solid slab covers and frequent cleaning and maintenance of these oil interceptors as these are the factors that affect their performance and require serious attention for the interceptors to function properly and effectively.