Propane heating value

If the substitute fuel is of the same general type, eg, propane for methane, the problem reduces to control of the primary equivalence ratio. For nonaspiring burners, ie, those in which the air and fuel suppHes are essentially independent, it is further reduced to control of the fuel dow, since the air dow usually constitutes most of the mass dow and this is fixed. For a given fuel supply pressure and fixed dow resistance of the feed system, the volume dow rate of the fuel is inversely proportional to. ypJ. The same total heat input rate or enthalpy dow to the dame simply requires satisfactory reproduction of the product of the lower heating value of the fuel and its dow rate, so that WI = l- / remains the same. WI is the Wobbe Index of the fuel gas, and... 

There are direct substitutions of possible interest that would not be feasible without drastic changes in the feed system or pressure. Thus if the available substitute for natural gas is, eg, a manufactured gas containing much CO, there would almost always be a mismatch of the WIs unless the fuel could be further modified by mixing with some other gaseous fuel of high volumetric heating value (propane, butane, vaporized fuel oil, etc). Moreover, if there are substantial differences in eg, as a result of the presence of considerable H2 as well as CO in the substitute gas, the variation in dame height and dashback tendency can also make the substitution unsatisfactory for some purposes, even if the WI is reproduced. Refinements and additional criteria are occasionally appHed to measure these and other effects in more complex substitution problems (10,85). 

Another objective of gas processing is to lower the Btu content of the gas by extracting heavier components to meet a maximum allowable heating limit set by a gas sales contract. If the gas is too rich in heavier components, the gas will not work properly in burners that are designed for lower heating values. A common maximum limit is 1100 Btu per SCF. Thus, if the gas is rich in propane and heavier components it may have to be processed to lower the heating value, even in cases where it may not be economical to do so. 

When liquefied, propane has a Btu content of 91,044 per gallon (higher heating value). At ordinai y temperatures, propane is relatively unreactive with other chemicals such as acids, alkalis, or oxidizers. 

Propane is a more reactive paraffin than ethane and methane. This is due to the presence of two secondary hydrogens that could be easily substituted (Chapter 6). Propane is obtained from natural gas liquids or from refinery gas streams. Liquefied petroleum gas (LPG) is a mixture of propane and butane and is mainly used as a fuel. The heating value of propane is 2,300 Btu/ft. LPG is currently an important feedstock for the production of olefins for petrochemical use. 

Boiler Thermal Efficiency Traditionally, boiler thermal efficiency is calculated pour/pm, where in is the LHV (lower heating value) of the fuel. A rule of thumb for economizers is that boiler efficiency increases by 1 percent for every 22°C (40°F) drop in temperature of the dry flue gas. These two statements do not reveal the considerable quantity of additional heat, available to be recovered through condensation of the water vapor in the flue gas, which is lost to atmosphere with hot flue gas. Based on fuel HHV (higher heating value), the total latent heat loss can be substantial an additional 9.6 percent (natural gas), 8.0 percent (propane), 6.5 percent (heating ou). 

Liquefied propane is marketed as a fuel for outlying areas where other fuels may not be readily available and for portable cook stoves. In this form, the propane may be marketed as LPG (liquefied petroleum gas) or mixed with butane and pentane, the latter also constituents of natural gas (1.7% and 0.6%, respectively), LPG also is transported via pipelines in certain areas. The heating value ofpure propane is 2520 Btu/ft3 (283 Calones/m3) butane 3260 Biu/fL3 (366 Calories/m3) and pentane 4025 Btu/ft3 (452 Calories/m3). Propane and the other liquefied gases are clean and appropriate for most heating purposes, making them very attractive where they are competitively priced. 

Applications of IR analyzers include the measurement of ammonia, CO, C02, ethylene, hexane, methane, moisture, nitrous oxide, propane, and sulfur dioxide. NIR analyzers can detect the concentrations of benzene, caustic, cetane, gasoline boiling point, heating value, molecular weight, octanes, protein, and p-xylene. The measurement errors of these analyzers are IR—2% FS, NIR—1% FS. 

Calculate the gross heating value in Btu/lbmol for a combustible gas mixture of 75 mol % methane, 10 mol % propane, and 15 mol % n-butane. The following gross heating value data are available ... 

Burner System. A modified 5.28 GJ/h burner is also on site to combust the low heating value gas. The burner consists of a 15 cm special wide range burner, pressure pilot, flame rod, combustion air blower with motor, micro ratio valve assembly and an emergency shut off valve. The burner size has been increased compared to a normal burner operating with natural gas. The pilot is operated on propane to ensure adequate ignition. 

Ethane heat flux 23 to 28 kW/m at exit conditions with double values at inlet Propane heat flux 14 to 17 kW/m at exit conditions with double values at inlet Butane or naphtha heat flux 11 to 15 kW/m at exit conditions at inlet the values are twice as large. 

The fuel used for experiments was a typical LPG used by industry, composed of more fhan 98% propane, 0.9% ethane, and 0.8% butane with lower heating value equal to 93.2 MJ/Nm3. 

First, let s calculate the total amount of heat released (or firing rate) from the flame. The total heat release (HR) is calculated by multiplying the fuel flow rate, rh, by the lower heating value (LHV) of fuel. Knowing the LHV of propane is 21,500 Btu/lb the heat release can be determined ... 

Surrogates of LPG can be made by blending mixtures of propane, butane, and natural gas. The surrogate LPG fuel should closely match the heating value and molecular weight of the actual fuel. 

The endothermic cracking of hydrocarbons [see also Eq. (3.22) in Section 3.2], shown here for propane, consumes only about 5% of the lower heating value of this fuel ... 

Wood, a renewable source, is not an important industrial fuel today. However, its use continues in some mral areas where it is often supplemented with liquid propane. In some underdeveloped countries, wood is still the principal source of energy. Dry wood contains from 1% to 12% moisture whereas green wood contains from 26% to 50% water. The resinous woods, like pine or cedar, yield about 18.5 MJ/kg of air-dried wood or, allowing for the moisture content, about 21 MJ/kg on a dry weight basis. Hardwoods have a heating value of about 19.4 MJ/kg. The energy available in present forest stocks is estimated to be equivalent to about 270 x 10 t of coal or about 2/3 of the equivalent oil reserves. 

We have a new, proprietary catalyst, and the kinetics are included in Table C.17. We would also like you to consider the economics of our continuing to use propylene with 5% propane inpurity at 0.095/lb versus purer propylene feed. In preparing this preliminary design, you should assume that all steam made can be used elsewhere in the plant with the appropriate economic credit, that condensed steam can be returned as boiler feed water for the appropriate credit, and that fuel gas can be burned for credit at its LHV (lower heating value). Additional information is given in Table C.18. 

A method of maintaining a constant-pressure fuel gas of uniform calorific value is indicated in Fig. l4-5. Liquid propane or butane may be fed into the system (sometimes actuated by an automatic calorimeter) to maintain the heating value, and natural gas is a< tted to carry the main heating load if process gases are insufficient. When sufficient process gas is produced to maintain well over 30 lb pressure in the balance tank, all... 

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