Solar Boiler System

A solar boiler system comprising:

• a boiler for burning fossil fuel;
• a primary air draft fan for generating air for transportation which allows pulverized fossil fuel to be pneumatically transported to the boiler;
• a primary air heater for preheating the air for transportation sent from the primary air draft fan;
• a forced draft fan for generating air for combustion of the boiler;
• a secondary air heater for preheating the air for combustion sent from the forced draft fan;
• and
• a secondary air superheater for superheating the air for combustion at an outlet of the secondary air heater by using solar thermal energy as a heat source.

A method of retrofitting an existing boiler system, the existing boiler system including:

• a boiler for burning fossil fuel;
• a primary air draft fan for generating air for transportation which allows pulverized fossil fuel to be pneumatically transported to the boiler;
• a primary air heater for preheating the air for transportation sent from the primary air draft fan;
• a forced draft fan for generating air for combustion of the boiler;
• and
• a secondary air heater for preheating the air for combustion sent from the forced draft fan;
• the method comprising the step of additionally installing:
• a solar heat recovery apparatus for collecting solar thermal energy;
• and
• a secondary air superheater for further superheating the air for combustion at an outlet of the secondary air heater by using solar thermal energy collected by the solar heat recovery apparatus as a heat source.