How does mechanical draft differ from natural draft in boilers?

Mechanical draft utilizes fans to actively move air through the boiler system, which enhances combustion by controlling the airflow precisely. This allows for better regulation of air supply, leading to improved combustion efficiency and the ability to maintain desired operating conditions regardless of external factors. On the other hand, natural draft is based on the natural buoyancy of warm air, which creates a pressure difference that draws air into the boiler. This method relies heavily on temperature differences and stack height, making it less controllable compared to mechanical draft. Therefore, the fundamental distinction lies in how the air is moved: mechanically through fans in mechanical draft and naturally through buoyancy in natural draft.