Document qa9rye2xY06Kxq19GqgqGEdgK

!' lI1j iLi<\,1 ? ! L i i' '! ;yt- ! i 1956 Guide '-55 s,. ia ti. u9 \ & b- 6 O *5 .J a gn 3 D. . o tQzo a '. |o Ob o O aZ< . Eso oi . 'HtnZo JAD i 2 pa sSJ H o oia J Eto '-'H pe Gross Net Grosa Air 3950 14093 3983 5940 lT 1 0C5O 1 : CN tCoO 05 05 C3 0cq5 4 0C0O CO SI cq to coqo ccqo 0r5- . oCO. CcqO . 11 1 1 1 1 to o <N to eq o CO to CO to o to o to to CO 05 4 CO CO CO 'a r- r- o cq CO o o 05 0to0 CO to 4*. ep- csi CO Tl4 c-OH . C4O.- CO tr"o4 ' to to to eo CcOO cq oo OlO H o o 0055 CO ro* cq co .co CrOCO 05 r- r--1 r-H CcOo 0to0 co .co ocO s CO- .eo co cq I i i 1 (CNO CO o oo ciC*oHO 1499 1792 325 647 2590 3370 2520 3260 l i i 1 1 . o cq roCN 0<OcNq5 CO scq to to tcoo 00V55H o C0i--O5t to 0005 ...t0o5 23879 21500 21644 22320 60958" 7100 21661 21308 21560 '21180 CO. l 1 1 1 05 co- oCoOo. l S ico r-H 1 ct--o Cc*--Oqi I o0o5 0055 CCHOO ecooo 0ocO0 o0oH0 05 o ' it0o5 ocoq 00 ocoq 05 ooo A C5 2. .o 8s o 'to to tCoO *cq + + cOCoN to too 4* 4* 4- d oo(N II o<N '+ Cq cq o + &Q 4- <N oo + cq + oo D + g 4* s5 cq ocq u 6CO 4- to O o n 6r-- 4- cq to u .. T 2. tCoq. t0o4 o oeo a oto 4* to d o00 (I dCO fH 4- to' d. 5S |22; SCO IIII tge tdo ft! d Si d to 00 to &< . ft! o .ci g"a. M".S5 S oo o CO *'3oao2 s ao xj a c3 X2fl 6 -S < 0a3 . a a 'fl ObC MOl arf o Cahj 4; a 2 > > -2 CQ to W PM a o V 2o O t0--5 2 o2 O %% i g d(SJ9ad S<,>0 -g33 01 o 3-g* Sag ,S ! B 58; ">3 O8 ">3 0A O Fuels and Combustion 357 ing value so-determined is termed the gross or higher heating value, and this is what is ordinarily meant when the heating value of a fuel is specified. In burning the fuel, however, the products of combustion are not cooled to ' the dew-point and the higher heating value cannot be utilized. When combustion is complete, the carbon in the fuel unites with oxygen to form carbon dioxide, C0i, the hydrogen unites with oxygen to form water vapor, HiO, and the nitrogen, being inert, passes through-the re action without change.. When combustion is incomplete, some of the carbon may unite with oxygen to form carbon monoxide, CO, and some of the hydrogen and hydrocarbon gases may not be burned at all. When carbon monoxide or other combustible gases, are present in the flue gases, there is a loss of heat produced per unit of :fuel consumed, and a lower combustion efficiency is obtained. Incomplete combustion may result from any or all of the following three conditions: (1) inadequate air supply, (2) insufficient mixing of air and gases, and (3) a temperature too low to produce ignition or maintain combustion. AIR REQUIRED FOR PERFECT COMBUSTION Air requirements for combustion of solid and. liquid fuels are ordinarily expressed in pounds. On the other hand similar, requirements for gaseous fuels are usually-stated on a cubic foot basis. For solid and gaseous fuels this method of treatment corresponds to the standards of measurement commonly employed by these two industries. The weight of air required for perfect combustion, per pound of solid or liquid fuel may be calculated after substitution of the proper percentages by weight of the various elements obtained from an ultimate analysis of the fuel in Equation 2. For gaseous fuels see Equation 3 for volume of air required. Solid or Liquid Fuels: .. , 34.56 rC ( 0\ S' Pounds air required per pound fuel = ----- -- + I H -- -- 1 + - 100 13 \ o/o (2> For Gaseous Fuels: Cubic feet air required per cubic foot gas = 2.39 (CO + Hi) + 9.53 CH, + 16.68 CiH, + 23.82 CJI, + 30.97 C,HI0 + 11.91 CtH, + 14.29 CJI, + 7.15 HiS - 4.78 0,.+ 30.47 UluminantB (3) Gaseous fuels may contain a wide variety of components classified as illuminanls, which are not separated by the usual methods of gas analysis. The principal ones in addition to ethylene and acetylene which are included in Equation 3, with the air required per cubic foot of gas are: propylene, 24.44; butylene, 28.58; pentene, 35.73; benzene, 35.73; toluene, 42.88; and xylene, 50.02. Since toluene and xylene are normally scrubbed from the gas before distribution, they may be disregarded in computing air. required for a fuel gas. An approximate value of 30.47 (as shown in Equation 3) may, therefore, be employed. If ethylene and acetylene are included as illuminanls, it is suggested that the value 19.65 be used. If it is desired to make the gas calculations on a weight basis the equation is expressed as follows: Pounds air required per pound fuel = 2.47 CO + 34.34 Hi + 17.27 CH, + 16.12 C,H, + 15.70 C,H, + 15.49 CJIi0*+ 13.30.Cjff, +. .. (4) 14.81 CJI, + 6.10 HS - 4.32 0,