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Show • The flame remained stable during the whole test series, regardless of the fuel used. • Temperatures in the combustor showed an increasing trend with decreasing hydrogen content. The relative temperature rise of the combustor liner by fuel types, over the base value established with diesel oil, was moderate as illustrated in Figure 6. Temperatures in the hottest row of finned segments rose only 9 percent under the most adverse condition with PFO. PFO had 6 percentage points lower hydrogen content than the base case diesel fuel. This additional heat load, however, was easily accommodated because the combustor was originally designed for flame emissivities close to unity. Results concerning pollutants indicated: • Emission levels for CO, C02, UHC, PNA, smoke and particles were low and well within industrial practice. • Water injection was required to keep the NO emissions below the EPA Standard. • Fuel bound nitrogen made only small incremental contribution to the total NO emissions. x Detailed presentation of the results, their interpretation, emission control techniques used and the related efficiency losses suffered are the subject of the following two chapters. VI. POLLUTANT EMISSIONS One of the prime reasons for conducting the full scale BBC type 9 gas turbine combustion tests [9,10] was to establish the effect of selected fuel properties on emissions. Results from the base case diesel fuel combustion tests were directly compared to those obtained from PFO, shale oil and EDS firing and to some earlier test data. The selection of PFO represented a fuel with an extremely low hydrogen to carbon ratio but exempt of FBN, as 1.4.6 |