Boiler Energy Saving and Waste Heat Recovery

A burner that utilizes flue gas waste heat for air preheating, also known as a high-temperature burner, high-temperature resistant gas burner, air preheating burner, boiler high-temperature burner, boiler high-temperature burner, energy-saving high-temperature burner, boiler flue gas waste heat recovery, gas boiler energy saving, gas waste heat recovery, boiler energy-saving air preheating burner, thermal oil boiler burner, heat carrier boiler burner. Depending on the application site, it can save 4-10% of energy.

In recent years, energy shortages and rising fuel costs have significantly increased the operational costs of equipment across various industries! Energy conservation and emission reduction have become goals for corporate reform, with waste heat recovery and utilization being a top priority. However, most conventional burners cannot withstand excessively high temperatures, limiting the recovery and utilization of flue gas waste heat. We have dedicated extensive efforts to research and develop

high-temperature resistant air preheating burners in a full series: air preheating oil burners, air preheating gas burners, air preheating dual-fuel (oil/gas) burners. We have developed combustion systems focused on energy conservation and emission reduction, with numerous successful applications to date, highly praised by users.

Industrial processes often discharge high-temperature flue gas at 200–300°C or above. Conventional combustion systems primarily use ambient temperature air for combustion support. If the combustion air temperature can be increased by over 100°C, fuel consumption can be relatively reduced, significantly lowering costs. This is particularly advantageous in regions where low-pressure air atomization combustion methods are used and heavy oil quality is relatively unstable,

offering substantial benefits for corporate energy savings and cost reduction. We install air preheaters at the chimney outlet, significantly increasing the boiler's intake air temperature. This technology enhances combustion efficiency, improves combustion conditions, and reduces chimney exhaust temperature, achieving energy savings (4–10%)

effects.

An air preheating burner is a high-temperature resistant burner with an intake air temperature of up to 150°C. It is a fully automated, load-adjusting forced-draft burner that can use liquid (fuel oil) or gaseous (gas) fuels.

An air preheating burner is also an energy-saving burner that effectively conserves fuel and reduces exhaust gas temperature. The combustion air is drawn from the environment (ambient temperature: 20°C–30°C). It utilizes the waste heat from combustion flue gas to preheat the combustion air via a heat exchanger. Preheated air mixed with fuel enhances combustion efficiency and quality, effectively saving fuel (a 100°C increase in combustion air temperature saves approximately 3.9% energy) while reducing exhaust gas temperature and carbon emissions.

The working principle of an air preheating burner is similar to that of a conventional fully automated forced-draft oil, gas, or dual-fuel (oil/gas) burner. The key difference lies in utilizing flue gas (waste gas) waste heat to preheat the combustion air.

The typical combustion air temperature range for an air preheating burner is from 50°C to 250°C, and in个别 cases, it can exceed 300°C.

As the temperature increases, the density of combustion air decreases. The air/fuel flow ratio of an air preheating burner differs from that of a conventional forced-draft (ambient temperature) burner.

Conventional forced-draft oil or gas burners draw combustion air from the environment (ambient temperature). After mixing with fuel, the combustion temperature exceeds 1000°C, used to heat the medium within thermal energy equipment. The high-temperature flue gas (waste gas) produced after combustion is discharged into the atmosphere through the chimney, polluting the environment.

For example:

1. Steam boiler: medium temperature ~160°C; flue gas temperature ~250°C

2. Thermal oil heater (heat medium boiler): medium temperature ~300°C; flue gas temperature ~380°C

Such equipment discharges a significant amount of thermal energy through flue gas (waste gas). Effective thermal energy recovery solutions can conserve energy.

Installing a flue gas/air heat exchanger at the flue gas outlet of such equipment reduces exhaust gas temperature while increasing combustion air temperature, thereby saving fuel. However, the burner must be high-temperature resistant.

Note:

1) The combustion air required for natural gas combustion = 1.234 (kg/hr)/kW (theoretical air-fuel ratio, λ=1.0); during operation (λ=1.15), the combustion air required for natural gas ≈ 1.419 (kg/hr)/kW

2) For every 100°C increase in combustion air temperature, fuel savings of approximately 3.9% can be achieved, while reducing carbon emissions (calculated based on natural gas combustion) by approximately 0.05 (kg/hr)/(°C-M