Fuel oils firing temperature

The high-chromium casting alloys (50% nickel, 50% chromium and 40% nickel, 60% chromium) are designated for use at temperatures up to 900 C in furnaces and boilers fired by fuels containing vanadium, sulfur and sodium compounds (e.g., residual petroleum products). Alloys with lower chromium contents caimot be used with residual fuel oils at temperature above 6S0 C because the nickel reacts with the vanadium, sulfur and sodium impurities to form compounds that are molten above 6S0 C [27]. 

To date, the test program has consisted of two periods of No. 6 fuel oil firing, two periods of SRC-II firing, and two combustion runs on No. 2 oil. Each test period was preceded by a few brief tests to shake down the boiler and determine settings for the atomizing air flow, fuel preheat temperature, and fuel/air proportioning controller. To date, eight runs have been made with No. 6 oil five at about 23% excess air and three at about 11 excess air. Two runs have been completed on No. 2 oil one at 11% excess air and one at 20% excess air. Five SRC-II fuels have been tested a... 

A relatively new type of air heater is one that uses a thermal fluid, which is a special oil that transfers heat from a boiler to the air heater. The boiler may be gas or fuel oil fired. This type of heater may be used when steam is not available and the temperature of... 

In extremely cold environments, engines can quickly become difficult, sometimes nearly impossible, to start. If ordinary gasoline- or diesel-oil-fired heaters are used, the coolant circulation pump, air fan, etc, must be powered from the vehicle s batteries, thus curtailing the time the system can be used, especially at very low temperatures when it is needed the most. By adding PbTe thermoelectrics to such heater systems, about 2% of their thermal output can be turned into electricity to mn the heater s electronics, fuel pump, combustion fan, and coolant circulation pump, with stiH sufficient power left over to keep the vehicle s battery fliUy charged. The market for such units is in the hundreds of thousands if manufacturing costs can be reduced. 

Furnaces for Oil and Natural Gas Firing. Natural gas furnaces are relatively small in size because of the ease of mixing the fuel and the air, hence the relatively rapid combustion of gas. Oil also bums rapidly with a luminous flame. To prevent excessive metal wall temperatures resulting from high radiation rates, oil-fired furnaces are designed slightly larger in size than gas-fired units in order to reduce the heat absorption rates. 

The aniline clo d point is a measure of the paraffinicity of a fuel oil. A high value denotes a highly paraffinic oil while a low value indicates an aromatic, a naphthenic, or a highly cracked oil. The flash point represents the temperature to which a liquid fuel can be heated before a flash appears on its surface upon exposure to a test flame under specified conditions. A knowledge of the flash point is needed to ensure safe handling and storage without fire hazards. 

A valve that closes in case of fire should be inserted in the oil fuel line to the oil-burning equipment and fitted as close to the tank as possible. It may be held open mechanically, pneumatically or electrically. Temperature-sensitive elements should be arranged to close the valve at a fixed maximum temperature, and sited close to the oil-fired plant and well above floor level. The operating temperature of the heat-sensitive elements should not be greater than 68°C (155°F) except where ambient temperatures in the vicinity of the plant may exceed 418°C (120°F), in which case the operating temperatures may be 183°C (200°F). 

Where gas or oil appliances are used for heating and installed within the heated space, between 70 per cent and 90 per cent of the total energy content of the fuel input will be converted into useful heat. Table 27.15 gives particulars of some gas-fired equipment types and Table 27.16 gives similar details for some oil-fired heaters. The first three types of equipment detailed in Table 27.15 and the first two in Table 27.16 are usually used for local warming of individuals rather than to provide a particular temperature throughout the space. 

Condensing boilers are now available for both gas- and oil-fired plant, the advantage of these being that the flue gases are further cooled down to below 100°C so that the latent heat available in the flue gas water vapor is recovered. The condensate has to be removed and the boiler capital cost is higher than for conventional plant. However, the boiler plant efficiency is increased to the order of 90 per cent, based upon the fuel gross calorific value. Where the flue gas exit temperatures are in excess of 200° C a further economy can be obtained by the provision of a spray recuperator in the case of gas and flue gas economizers for oil and coal. 

The ground mixture is heated to about 750 °C under reducing conditions, normally in a batch process. This can be done in directly fired kilns with the blend in lidded crucibles of controlled porosity, or muffle kilns. The heating medium can be solid fuel, oil, or gas. The sodium carbonate reacts with the sulfur and reducing agent at 300 °C to form sodium polysulfide. At higher temperatures the clay lattice reforms into a three-dimensional framework, which at 700 °C is transformed to the sodalite structure, with entrapped sodium and polysulfide ions. 

Cleveland Open Cup (COC)-test (ASTM D 92) for determining the flash point and fire point of all petroleum products except fuel oil and products with flash points below 79oC (175oF). The oil sample is heated in a precisely specified brass cup containing a thermometer, specified intervals a small flame is passed across the cup. The lowest temperature at which the vapors above the cup briefly ignite is the flash point the temperature at which the vapors sustain combustion for at least five seconds is the fire point. See Tag open cup. 

In establishing the relative levels of PNA emissions from EDS fuel oils and petroleum fuels, all experiments were run in a 50 hp fire tube boiler under nominally identical combustion conditions. These were an excess 02 level of 2 percent, fuel feed rate of 0.45 kg/min., and a nozzle temperature such that the fuel viscosity was about 30 cSt to maintain equivalent atomization. 

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