A hot air blower, including: an air channel for blowing a main stream of air therethrough by an electric fan; a gas tank, for supplying burning gas; a gas burner, including: an air inlet, disposed within the air channel, for receiving a first portion of the main air stream; a burning gas inlet for receiving the burning gas; and an outlet, disposed within the air channel, thereby the gas burner produces a flame at the outlet within the air channel, for heating the main air stream; and a mechanism, for automatically fitting a size of the air inlet to an extent of the main air stream and consequently to an extent of the second portion thereof.

An example flow regulation system for a biochar kiln includes an air inlet port of the biochar kiln. The example flow regulation system also includes a port cover coupled to the air inlet ports. The example flow regulation system also includes an external flow regulation assembly coupled with the port cover. The example flow regulation system also includes a controller operating the external flow regulation assembly based on monitoring conditions of the biochar kiln to open and close the air inlet port.

An example flow regulation system for a biochar kiln includes an air inlet port of the biochar kiln. The example flow regulation system also includes a port cover coupled to the air inlet ports. The example flow regulation system also includes an external flow regulation assembly coupled with the port cover. The example flow regulation system also includes a controller operating the external flow regulation assembly based on monitoring conditions of the biochar kiln to open and close the air inlet port.

A coal-fired power generation system may include a boiler outputting flue gas, a coal pulverizer associated with the boiler, and a heat exchanger. The heat exchanger may be configured to exchange heat from the flue gas to a primary air path and a secondary air path. The primary air path is coupled to the coal pulverizer, and the secondary air path is coupled to the boiler. The coal-fired power generation system may include a controllable air recirculation path coupled from an output of the primary air path to an input of the secondary air path.

A coal-fired power generation system may include a boiler outputting flue gas, a coal pulverizer associated with the boiler, and a heat exchanger. The heat exchanger may be configured to exchange heat from the flue gas to a primary air path and a secondary air path. The primary air path is coupled to the coal pulverizer, and the secondary air path is coupled to the boiler. The coal-fired power generation system may include a controllable air recirculation path coupled from an output of the primary air path to an input of the secondary air path.

A system for operating a damper comprises a flue pipe assembly, and a damper movable between an open position and a closed position within the flue pipe assembly. At least one thermoelectric generator is coupled to a surface of the flue pipe assembly. Operation of the damper is achieved by the thermoelectric generator harvesting thermal energy from the flue pipe assembly and converting it into usable electrical energy for actuation of the damper.

A system for operating a damper comprises a flue pipe assembly, and a damper movable between an open position and a closed position within the flue pipe assembly. At least one thermoelectric generator is coupled to a surface of the flue pipe assembly. Operation of the damper is achieved by the thermoelectric generator harvesting thermal energy from the flue pipe assembly and converting it into usable electrical energy for actuation of the damper.

An example exhaust system for a biochar kiln includes a chimney of the biochar kiln. The example exhaust system for a biochar kiln also includes a first forced air inlet on the chimney to draw smoke through the chimney during a preheating stage to prime the chimney. The example exhaust system for a biochar kiln also includes a second forced air inlet operatively coupled with the chimney. The second forced air inlet activated to increase airflow when air naturally occurring in a smoke stream in the chimney is insufficient, the second forced air inlet deactivated when there is sufficient air.

An example exhaust system for a biochar kiln includes a chimney of the biochar kiln. The example exhaust system for a biochar kiln also includes a first forced air inlet on the chimney to draw smoke through the chimney during a preheating stage to prime the chimney. The example exhaust system for a biochar kiln also includes a second forced air inlet operatively coupled with the chimney. The second forced air inlet activated to increase airflow when air naturally occurring in a smoke stream in the chimney is insufficient, the second forced air inlet deactivated when there is sufficient air.

An example flow regulation system for a biochar kiln includes an air inlet port of the biochar kiln. The example flow regulation system also includes a port cover coupled to the air inlet ports. The example flow regulation system also includes an external flow regulation assembly coupled with the port cover. The example flow regulation system also includes a controller operating the external flow regulation assembly based on monitoring conditions of the biochar kiln to open and close the air inlet port.