Lin Cherng-Yuan, Chen Wei-Cheng
Department of Marine Engineering, National Taiwan Ocean University, Keelung, Taiwan, ROC.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2004;39(1):281-97. doi: 10.1081/ese-120027384.
A marine furnace made of stainless steel. combined with an automatic small-size oil-fired burner, was used to experimentally investigate the influences of calcium oxide content in fuel oil on the combustion and emission characteristics under varying temperatures and humidity of the inlet air. Marine fuel oil generally contains various extents of metallic oxides such as CaO, Fe2O3, V2O5, etc which might affect its burning properties. In this study, an air-conditioner was used to adjust the humidity and temperatures of the inlet air to preset values prior to entering the burner. The adjusted inlet air atomized the marine diesel oil A containing a calcium oxide compound, to form a heterogeneous reactant mixture. The reactant mixture was thereafter ignited by a high-voltage electrode in the burner and burned within the marine furnace. The probes of a gas analyzer, H2S analyzer and a K-type thermocouple were inserted into the radial positions of the furnace through the eight rectangular slots which were cut in the upper side of the furnace. The experimental results showed that an increase of either humidity or temperature of the inlet air caused the promotion of the reaction rate of the fuel. The existence of calcium oxide compound in the diesel fuel also facilitated the oxidation reaction in the combustion chamber. The addition of CaO in the diesel fuel under the conditions of higher temperature or higher relative humidity of the inlet air produced the following: higher concentrations of CO2, SO2, and H2S emissions, an increased burning efficiency, a lowered O2 level, production of excess air and NOx emissions as well as a lower thermal loss and a lower burning gas temperature, as compared with the conditions of a lower temperature or a lower humidity of the inlet air. In addition, the burning of diesel fuel with added CaO compound caused a large variation in the burning efficiency, thermal loss, plus CO2, O2, and excess air emissions between the conditions of higher temperature/higher humidity and lower temperature/lower humidity inlet air compared with no CaO addition in the fuel. Moreover, the burning efficiency and the concentrations of excess air and O2 emissions increased, while the thermal loss, burning gas temperature and H2S, SO2, NOx, and CO2 emissions decreased with the increase of the axial distance from the measured location to the burner nozzle.
一个由不锈钢制成的船用熔炉，与一个自动小型燃油燃烧器相结合，用于实验研究燃油中氧化钙含量对不同进气温度和湿度下燃烧及排放特性的影响。船用燃油通常含有不同程度的金属氧化物，如CaO、Fe2O3、V2O5等，这些可能会影响其燃烧性能。在本研究中，使用空调在进气进入燃烧器之前将进气的湿度和温度调节到预设值。调节后的进气使含有氧化钙化合物的船用柴油A雾化，形成非均相反应物混合物。反应物混合物随后被燃烧器中的高压电极点燃，并在船用熔炉内燃烧。气体分析仪、H2S分析仪和K型热电偶的探头通过在熔炉上侧切割的八个矩形槽插入熔炉的径向位置。实验结果表明，进气湿度或温度的增加都会促进燃料的反应速率。柴油燃料中氧化钙化合物的存在也促进了燃烧室内的氧化反应。与进气温度较低或湿度较低的情况相比，在进气温度较高或相对湿度较高的条件下，柴油燃料中添加CaO会产生以下情况：CO2、SO2和H2S排放浓度更高，燃烧效率提高，O2水平降低，产生过量空气和NOx排放，以及热损失更低和燃烧气体温度更低。此外，与燃料中不添加CaO相比，添加CaO化合物的柴油燃料燃烧在进气温度较高/湿度较高和进气温度较低/湿度较低的条件之间，燃烧效率、热损失以及CO2、O2和过量空气排放有很大差异。而且，随着从测量位置到燃烧器喷嘴轴向距离的增加，燃烧效率以及过量空气和O2排放浓度增加，而热损失、燃烧气体温度以及H2S、SO2、NOx和CO2排放降低。
