July 13, 1998
Revisions to Boiler Spreadsheet
Mike Goldman



A new version of the boiler calculation spreadsheet is available for use.

The file name is BOILER6.XLS and is located in the g:\group\engr\library\software
directory.  The old BOILER5.XLS spreadsheet has been moved to the
g:\group\engr\library\software\old_docs directory.


CHANGES TO VERSION 6 (July 13, 1998)

Major changes to the revised macro-driven spreadsheet include:

-  Revised the default HHV for natural gas and field gas to 1020 Btu/scf per USEPA
AP-42 Supplement D (March 1998).  Note: The relevance of this is that to obtain the emission factors in units of "lb/MMBtu", one must use the default HHV of 1020 Btu/scf.  

-  Modified the Firing Type label to allow for selection of Tangential firing in all classes due to the addition of new NOx and CO emission factors for Tangential fired natural gas boilers.

-  Revised the emission factor over-ride choice menu to allow for the selection of Tangential gas-fired uncontrolled NOx and CO emission factors per USEPA AP-42 Supplement D (3/98).  This applies to all firing rates.  

-  Revised the natural gas and field gas emission factors based on USEPA AP-42 Supplement D update of 3/98.  Uncontrolled NOx, CO, TSP, PM10, ROC all changed. Specifically, categories were revised and the EFs themselves were updated.

-  Revised the Propane/Butane uncontrolled NOx, CO, TSP, PM10, ROC emission factors based on USEPA AP-42 Supplement D update of 3/98.

-  The ROC fraction for natural gas fired units was changed to 0.5 ROC/TOC based on USEPA AP-42 Supplement D (VOC/TOC = 5.5/11 = 0.5) and EPA defn of VOC equals APCD defn of ROC.



CHANGES TO VERSION 5 (March 6, 1997):

Major changes to the revised macro-driven spreadsheet include:

-  The Main Menu (dialog box) has been revised to eliminate errors that occured when trying to
save the spreadheet.  Now, to Save or print the spreadsheet, you must either Cancel or ESCcape out
of the macro.  To Print, simply click on the Print button on the Main Menu. To save, use the Excel
File|SaveAs feature off the Excell Toolbar.  To re-enter the macro, hit CTR-M.

-  Takes into account EPA's new classification cut-off for Commercial at 0.3 MMBtu/hr versus the 
older cut-off of 0.5 MMBtu/hr

-  ROC emission factors were revised for NG fuel for the Residential and Commercial categories

-  The default NOx and CO emission factors are now uncontrolled.  A dialog box has been added
that allows the user to select whether the NOx/CO emission factors should be RACT (Gas-Fired), 
RACT (Liquid-Fired), BACT (Small Gas-Fired) or Uncontrolled/User-Defined.  The Uncontrolled/User-
Defined option simply leaves the user's EF input as it was selected (the dialog box appears after
you are initially prompted to enter the EFs).    

-  Propane/LPG fuel EFs have been revised

-  The Fuel Type now allows the user to enter "Other".  This allows you to input data for a generic
fuel (ie, allows you to use the built in calculations).  If chosen, the user will need to provide all
relevent information such as: EFs, HHV and units, sulfur content and units).

-  Updated the density of diesel #2 from 7.13 to 7.05 lb/gal

-  Updated the HHV of propane from 2518 to 2522 Btu/scf
  

Please see me if you have any questions on using the spreadsheet or if you find any bugs.


mg