Page 476 - Boiler_Operators_Handbook,_Second_Edition

Appendices 461

This first worksheet converts the gas constituents from in the #/C cu. ft. column by the total and place the
volumetric to gravimetric portions. In other words, result in the % by weight column. Now that you know
it changes it from percent by volume to percent by the percent by weight of each gas you can convert those
weight. Insert the percent by cubic foot values for each values to pounds of carbon, hydrogen, etc. to develop
of the gases in the first open column. This tabulation is the gravimetric analysis using the next worksheet.
provided to accommodate a wide variety of gases and

Constituent % by wt. x = C x = H x = O x = N x = S
2 2 2 2
Methane % 0.7487 0.2513 0 0 0 0 0 0
Acetylene % 0.9226 0.0074 0 0 0 0 0 0

Ethylene % 0.8563 0.1437 0 0 0 0 0 0
Ethane % 0.7989 0.2011 0 0 0 0 0 0
Propylene % 0.8563 0.1437 0 0 0 0 0 0

Propane % 0.8171 0.1829 0 0 0 0 0 0
Butylene % 0.8563 0.1437 0 0 0 0 0 0
Butane % 0.8266 0.1734 0 0 0 0 0 0
Pentene % 0.8563 0.1437 0 0 0 0 0 0
Pentane % 0.8323 0.1677 0 0 0 0 0 0

Benzene % 0.9226 0.0774 0 0 0 0 0 0
Hexane % 0.8362 0.1638 0 0 0 0 0 0
Hydrogen % 0 1.0000 0 0 0 0 0 0

Ammonia 0 0 0.1776 0 0 0.8224 0 0
H S % 0 0.0592 0 0 0 0 0.9408
2
CO % 0.2729 0 0.7271 0 0 0 0
2
CO % 0.4288 0 0.5712 0 0 0
O % 0 0 1.0000 0 0 0 0
2
N % 0 0 0 0 1.0000 0 0
2
Totals %

Transfer the % by weight values from the first work- Always check your math by adding up the percentages.
sheet to the column in the second one. Multiply each They will seldom total 100% precisely but should be
value by the factors for carbon, hydrogen, oxygen, etc. very close to it.
in the succeeding columns then add them up. Add up
all the values for each element to get the totals for the The combustion calculation form has space for describ-
bottom of the worksheet and transfer those values to ing the fuel and indicating its source, and higher heat-
the combustion calculation sheet on the next page. Note ing value. The predicted stack temperature and excess
that moisture in percent by weight is included in the air percentage are used to determine the volume of the
first worksheet. flue gas. Additional instructions on its use follow the
combustion calculation form.