Coal fired package boiler

A coal fired shop assembled water tube steam boiler comprising:

• A. means defining a radiant heating section with upper and lower headers and tubes lining its walls and connecting the upper and lower headers;
• B. a curtain wall formed of substantially vertically oriented tubes connecting the upper and lower headers and dividing the radiant heating section vertically into primary and secondary combustion zones;
• C. a grate at the bottom of said primary combustion zone to support a bed of burning coal;
• D. means defining a gas outlet from the lower portion of the secondary combustion zone through which combustion gases and products of combustion emanating from the bed of burning coal may leave the radiant heating section after rising in the primary combustion zone and descending in the secondary combustion zone;
• E. means defining a convection heating section with vertically spaced steam and mud drums connected by external downcomer means and internal vertically oriented tubes;
• F. means defining a gas inlet near the bottom of the convection heating section and a gas outlet near the top thereof;
• G. pipe means for connecting the steam and mud drums of the convection heating section respectively with the upper and lower headers of the radiant heating section;
• and
• H. duct means for connecting the gas outlet of the radiant heating section with the gas inlet of the convection heating section,
• said pipe means and said duct means comprising separable sections respectively fixed with respect to said two heating sections so that the two heating sections can be independently fabricated and transported to an installation site and then mounted with the separable sections of the pipe means and the duct means in mating alignment for subsequent connection.