Heat Recovery of Industrial Exhaust Gases

Heat Recovery of Industrial Exhaust Gases

Heat recovery and utilisation of industrial waste gases is an important means of improving energy efficiency and reducing environmental impact. By recovering and utilising the heat carried by high-temperature gases through the heat exchange principle, the temperature of the gases can be effectively lowered while providing thermal energy for industrial production and life.

1. Types of heat exchangers

Air-air heat exchanger: Used to recover heat from exhaust gases and transfer it to fresh air.

Air-water heat exchanger: transferring heat from exhaust gases to water, which can be used to heat industrial water or domestic hot water.

Flue gas heat recovery boiler: Converts the heat in the exhaust gases into steam or hot water, which is supplied to the production process or for heating.

2. Heat recovery process

Exhaust gas collection: High-temperature exhaust gas is guided to the heat exchanger through a pipework system.

Heat exchange:

The high temperature exhaust gas flows through the pipework of the heat exchanger and exchanges heat with the cooling medium (e.g. air or water) and the temperature of the exhaust gas is reduced.

The cooling medium absorbs the heat from the exhaust gas and the temperature increases.

Heat energy utilisation:

Industrial use: heating raw materials, preheating furnaces or boilers to reduce energy consumption.

Domestic use: Provide hot water for hot water system to meet the demand of domestic water.

3. Application examples

Metallurgical industry: In the process of blast furnace and steel making, the waste gas passes through the heat exchanger, and the recovered heat is used to preheat the fuel or heat the furnace material to improve efficiency.

Chemical industry: After the exhaust gas passes through the heat exchanger, the recovered heat is used to heat the reaction kettle or drying equipment to reduce energy consumption.

Power industry: flue gas passes through the heat exchanger, and the recovered heat is used to generate electricity or heat, which improves the thermal efficiency of the power plant.

Food industry: In the process of food processing, the heat of exhaust gas can be recovered for heating water or other production heat, improving production efficiency.

4. Advantages

Energy saving and environmental protection: by recovering the heat in the exhaust gas, it reduces the dependence on external energy sources and lowers energy consumption and carbon emissions.

Economic benefits: reduce production costs, improve energy utilisation and increase enterprise competitiveness.

Temperature control: effectively reduce the temperature of the exhaust gas, reduce the heat load on the subsequent processing equipment, and improve the safety of the equipment.