Basic Technical Requirements Of Dual Fuel Burner
Basic Technical Requirements Of Dual Fuel Burner
Dual fuel burner is a device that enters the furnace in a certain proportion, speed, and mixing mode to realize timely ignition and efficient and clean combustion. The equipment has a fully automatic combustion device with automatic ignition, flame monitoring, and automatic adjustment devices. At present, most of the oil and gas burners used in domestic industrial kilns belong to fully automatic burners.
Dual fuel burner is an important piece of equipment for oil and gas industrial furnaces. The combustion fuel can be divided into oil burner and gas burner, and there are also oil-gas dual-purpose burners with the function of burning two fuels (oil and gas or two different gases). A fuel burner mainly includes a fuel injector (atomizer), air regulator, etc., while a gas burner mainly consists of a gas nozzle or orifice, regulator, etc.
In order to meet the requirements of the combustion process in the furnace and ensure the safety, reliability, high efficiency, and low pollution emission of the equipment, the burner should have the following main technical performances:
(1) High combustion efficiency
In order to ensure combustion efficiency during high-speed operation, the fuel burner is required to have a good atomization effect within a certain working range, that is, after atomization by oil droplets, the particle size of oil droplets is uniform, the atomization angle is appropriate, the flow density distribution of oil mist along the circumference is consistent with that of air distribution, and the mixing effect of oil mist and the air is good.
Under the rated gas pressure, the gas burner shall be able to fully burn through the rated gas volume to achieve the rated heat load production.
(2) Reasonable air distribution, stable and sufficient fuel combustion
The root of the atomizing torch should be supplemented with an appropriate amount of air in time to prevent the decomposition of oil and gas into carbon black through high temperature and low oxygen conditions, and form a reflex area with the appropriate size and location at the outlet of the combustion airflow and place the fuel and air in a higher temperature field to ensure rapid and stable ignition. In the middle and late stages of combustion, the air and oil mist should be mixed quickly and evenly to ensure complete combustion, And minimize the harmful substances (CO, no, etc.) produced in the combustion flue gas.
(3) The shape and length of the combustion flame should be consistent with the furnace, the flame has good fullness, and the flame temperature and blackness should meet the requirements of the furnace. Do not let the flame wash the convection heating surface of the furnace wall, furnace bottom, and outlet window.
(4) Good regulation performance. The burner shall be able to meet the requirements of furnace load regulation, that is, between the minimum load and the maximum load of the furnace, the burner can work stably without tempering and de ignition.
(5) The less energy the nozzle consumes in the atomization process, the better.
(6) The air regulating device has small wind resistance and low operating noise.
(7) Ignition, speed regulation, and other operations are convenient, safe, and reliable.
(8) The structure is simple, compact, reliable, highly automated, and easy to maintain.
The combustion condition of oil-gas boilers and kilns mainly depends on the working performance of burners. Poor atomization quality of oil burner or unreasonable air flow distribution will lead to the following adverse consequences:
(1) Incomplete combustion pollutes the heating surface at the tail of the boiler, and the smoke temperature rises, even causing secondary combustion.
(2) The heat loss of incompletely burned combustible gas increases.
(3) The heat loss of flammable solid combustion increases.
(4) Coking at the burner outlet or in the furnace.
(5) Accidents such as flameout, blasting and even furnace explosion occur.