“Environmental Boiler” is a relatively general concept. In a broad sense, it refers to the emission of emissions such as waste gas and waste, and it is a boiler that does not only refer to a certain type of boiler.

According to China's latest air pollutant emission standards in some areas, the minimum emission standards for nitrogen oxides in Beijing, Zhengzhou and Xi'an have dropped to 30 mg/m³.

For fuel gas boilers, it is an “environmental boiler” by using advanced combustion technology or an environmentally friendly burner to achieve nitrogen oxide emissions of less than 30 mg/m³.

Electric boilers need not be elaborated. Because of the use of electricity as a power source, there is no emission of waste gas, which is even more of an "environmental boiler" type.

Most of the environmentally friendly boilers use FGR, full premixing and other advanced combustion technologies to reprocess the flue gas, reuse the flue gas waste heat, and reduce the flue gas temperature. It can not only improve the thermal efficiency of the boiler, but also reduce the emission of harmful substances in the flue gas, and realize the social and economic benefits of environmental protection and energy conservation.

FANGKUAI Boiler has many years of experience in clean boiler manufacturing and sales, and has a number of patented R&D technologies. The boilers produced meet the most stringent air pollution emission standards in China. If you have any needs or problems with the "environmental boiler", you can get in touch with our company directly, and the professional technical engineer will answer your questions in real time.

Nitrogen oxide is one of the main sources of pollution causing air pollution. It is extremely destructive to human body, animals and plants, and the environment. Excessive emission of nitrogen oxides will directly threaten our lives.

Nitrogen and oxygen are not actively mixed together, but when the temperature reaches 1600 ° C, nitrogen and oxygen in the air are mixed to form nitrogen oxides.

At present, the low-nitrogen combustion technology of the gas boiler with better effect has full premixing and FGR.

First, full premixed combustion technology.
       Before the fuel is sent to the furnace for combustion, it is thoroughly mixed with the air beforehand, and the optimal ratio is achieved through precise adjustment and control. After adding surface combustion technology, the combustion temperature in the furnace is further reduced to reduce the role of nitrogen oxides.

Second, FGR combustion technology.
       FGR combustion technology is the flue gas recycling technology. The flue gas generated after the boiler is operated enters the furnace through the connecting pipe to participate in the combustion, and reduces the combustion temperature of the fuel in the furnace to reduce the role of nitrogen oxides.

If you are in the low-nitrogen reform of the headache boiler or want to buy a low-nitrogen boiler at this time, you can contact the FANGKUAI Boiler through the free service hotline above, we will be happy to help you.

Natural circulation and forced circulation are two kinds of circulation states during the operation of the boiler, and the two are essentially different. Fang Kuo Xiaobian will compare and compare these two cycle states, so that you can better understand the boiler operation knowledge.

First, the natural circulation.
       Working principle: The operation mode of actively promoting the water circulation by relying on the density difference caused by the heating of the working medium between the falling pipe outside the furnace and the rising pipe in the furnace. The circulation circuit is composed of a drum, a down pipe, a header, a riser pipe, a steam water introduction pipe and the like. The pot water descends from the outer down pipe of the furnace into the lower header of the water wall, and then is heated into a steam-water mixture (containing steam rate of 5-25%) through the furnace water wall (ie, the riser pipe), and then enters the drum through the soda water introduction pipe to perform steam-water separation. The saturated steam is sent to the superheater, and the pot water still returns to the down tube to continue the circulation.
       The main features of natural circulation boilers are:
       1. Work only under sub-critical pressure. Under the subcritical pressure, the natural circulation boiler with the flue gas parameter of 16.6~18.2 MPa and the working pressure of the drum reaches 18.6~20.6 MPa, and the natural circulation still has sufficient water circulation driving force to achieve safe and reliable operation.
          2. Has a fixed evaporation section end point. The drum separates the two sections of evaporation and superheating, which serve as the heat accumulator and water reservoir of the boiler respectively.
        3. Under the normal operating conditions, the design is correct, can maintain the appropriate circulating water flow rate or cycle rate (the ratio of the circulating water volume entering the rising pipe to its steam production), and has good self-compensation ability, that is, the heat absorption of the circuit increases. The circulating water flow rate also increases.
       4. Under the subcritical pressure, the water-cooled wall often adopts an internally threaded pipe to ensure the ability to effectively prevent the working fluid in the pipe from deviating from the nuclear boiling (DNB).
         5. The salt water concentration and steam quality of the pot water can be maintained by continuous sewage discharge in the drum. The quality of the feed water can be lower than that of the DC boiler, which can reduce the cost of the chemical water treatment part.
        6. The resistance of the steam-water system is small, and the water supply pressure is not high, which can reduce the power consumption of the feed pump.
        7. The drum is thick-walled, the cost is high, and there is a problem of temperature difference between the upper and lower sides and the inner and outer walls, and the starting and stopping time is extended.

Second, the mandatory cycle.
      Working principle: Under the action of the water pump head, the working medium passes through the preheating, evaporation and overheating heating surfaces, and is preheated, evaporated and superheated to the required temperature.
       The water or steam in the forced circulation boiler is not only powered by the difference in density between water and steam, but also requires a certain pump work to circulate in the heating pipe. Due to the good water circulation, the forced circulation furnace has a very low requirement for the water supply speed; the working pressure is generally large, and the material and the wall of the boiler tube are required to be high. The drum of the forced circulation boiler is no longer necessary. It can have a drum and can have no drum. However, the pump head has higher requirements and consumes more electricity. When the pump stops running, the flow of water in the pot also stops, and a reliable method is needed to prevent the water from vaporizing the water.

The difference between the forced circulation boiler and the natural circulation boiler is that the circulation between the downcomer of the natural circulation boiler and the heating surface is generated by the natural indenter between the two, and the forced circulation boiler is forced by the furnace water circulation pump. The forced circulation boiler on the equipment has a furnace water circulation pump (compulsory circulation pump), while the natural circulation boiler does not.
The horizontal boiler evaporation section is generally forced circulation, and the vertical boiler evaporation section is not necessarily a natural circulation, but may also be a forced circulation.

1. Rated thermal power: The thermal energy that the boiler can provide in a unit of time under rated conditions, generally expressed in megawatts (MW) or large calories (Kcal/H).
For boilers with thermal efficiency ≤1.4 MW, the exhaust gas temperature shall not be higher than the inlet medium temperature of 50 °C.
For boilers with a thermal efficiency >1.4 MW, the exhaust gas temperature must not exceed 170 °C.

2. Circulating water volume: The amount of water recycled in the boiler circulating water system.

3. Standard atmospheric pressure: The pressure of sea level at standard atmospheric conditions is 101.325 KPa.
Pressure: The air pressure is higher than the standard atmospheric pressure.
Vacuum: The pressure is below the standard atmospheric pressure.

4. Heating surface: The surface that absorbs heat from the heat release medium and transfers it to the surface of the heat medium, such as the furnace of the boiler, the cylinder, the tube, and the like.
Radiation heating surface: The heating surface that mainly absorbs heat from the heat release medium by radiation heat exchange, such as water wall, furnace gall, and lower abdominal wall of the drum.
Convective heating surface: The heating surface that mainly absorbs heat from high-temperature flue gas by convective heat transfer method, generally the heating surface of flue gas flushing, such as smoke pipe and convection pipe bundle.

5. Boiler thermal efficiency: The percentage of heat that is effectively used by the boiler and the amount of heat consumed by the fuel per unit time. The higher the thermal efficiency, the better the heat transfer performance.

6. steam quality: steam cleanliness, generally saturated steam with more or less traces of saturated water, with a quality of steam exceeding the standard amount of water.

7. Fuel consumption: The amount of fuel consumed by the boiler per unit time.

8. Discharge amount: The amount of sewage discharged when the boiler is discharged.

9. Natural circulation: the boiler boiler that actively pushes the water circulation by the difference of the working medium density between the down pipe outside the furnace and the rising pipe in the furnace. The circulation circuit consists of the drum, the down pipe, the header, the riser pipe, the soda water introduction pipe and the like. composition.
Forced circulation: Water or steam in the boiler should not only be driven by the difference in density of water vapor in the water, but also need to provide some pump power to circulate in the heating pipe.

10. Small boiler: steam boiler with water volume ≤ 50L and rated steam pressure ≤ 0.7MPa; hot water boiler with rated outlet pressure not exceeding 0.1MPa and hot water boiler with tap water pressure.

When the boiler is in the auxiliary machine configuration, the water treatment will be placed in the first place. What is the meaning of water treatment?
Simply put, boiler water treatment refers to pre-softening the water flowing into the boiler and then flowing into the boiler for related use.
Natural water contains various salts. These salts are dissolved in cations and anions, mainly composed of calcium and magnesium ions, and are collectively referred to as "hard water". The minerals contained in these hard water boiled in the container and gradually form a white block or powdery solid, which is what we often call "scale".

First, the main hazard of scale.
       1. Due to the extremely poor thermal conductivity of scale, heat absorption is reduced during heating, boiler thermal efficiency is reduced, fuel utilization is reduced, and boiler operating costs are increased. 2. Fouling will cause the temperature of the furnace wall to increase exponentially. The stress of the steel is destroyed and the strength is reduced. In severe cases, the bursting phenomenon will occur, which will seriously reduce the service life of the boiler.
         2. The calcium and magnesium ions in the water will be integrated into the water during the heating process, which will directly affect the steam quality. At the same time, if the boiler parts such as safety valves, pressure gauges and pressure controllers are scaled, it will cause blockage.

Second, the method of water treatment.
       Boiler water treatment usually uses a combination of a resin tank and a salt tank. When the raw water containing hardness passes through the resin layer of the exchanger, calcium ions and magnesium ions in the water are adsorbed by the resin while releasing sodium ions. The water that flows out of the exchanger is the demineralized water from which the hardness ions are removed. When the resin adsorbs a certain amount of calcium and magnesium ions, it must be regenerated. In the regeneration process, the resin layer is washed with a high-concentration sodium oxide solution in the salt can, and the hardness ions on the resin are replaced, and the resin is restored to the softening exchange function as the recycled waste liquid is discharged out of the tank.

Third, on-site practice.
       1. Check the inlet water pressure (0.2-0.4MPa); check whether the high-concentration brine in the pipe is sufficient; check whether the salt pipe and the sewage pipe are blocked; if there is any abnormality, start it after cleaning.
         2. Close the tap water bypass valve.
       3. Open the salt water inlet pipe valve and open the outlet pipe valve; open the demineralized water to the soft water tank manual and electric valve.
       4. The control valve is energized and the cycle water quantity parameter is set.
       5. start running.

When you purchase boiler equipment, you will pay attention to many problems, how much thermal efficiency, whether it is energy-saving and environmental protection, whether boiler manufacturers have special equipment installation and manufacturing certificates, etc., are the key points you need to pay attention to. At the same time, it is also important that the boiler is regularly maintained during use.

The gas boiler with regular maintenance can effectively extend the service life of the boiler, improve the working efficiency of the boiler, and reduce the incidence of failure, which is conducive to the normal and safe operation of the boiler. Gas-fired boilers that are regularly maintained have better service life, energy savings and failure rates than boilers that are not regularly maintained (especially those that have been in operation for more than one year).

Commonly used boiler maintenance methods are: pressure maintenance, wet maintenance, dry maintenance, and aeration maintenance.

First, pressure maintenance.
       Pressure maintenance is required when the furnace is not to be used for more than one week. Before the shutdown process is terminated, the steam water system is filled with water, the residual pressure is maintained at 0.05~0.1 MPa, and the temperature of the boiler water is maintained above 100 °C, which can effectively prevent air from entering the boiler.

Second, wet maintenance.
       Wet maintenance is required when the shutdown time is less than one month. Fill the boiler soda system with soft water containing lye, leaving no steam space. This is because an aqueous solution having an appropriate alkalinity forms a stable oxide film with the metal surface to prevent corrosion.

Third, dry maintenance.
       This method is used for maintenance when the furnace is stopped for a long time. The specific method is: after the furnace is shut down, the pot water is drained, the boiler is used to dry the boiler, and the residual scale and residue in the pot are removed in time, and then the tray containing the desiccant is placed in the drum and on the grate. Finally close all valves, manholes and hand hole doors. Regularly check the maintenance and replace the failed desiccant in time.

Fourth, inflatable maintenance.
       Inflatable maintenance can be used for long-term shutdown maintenance. After the boiler is shut down, do not release water, keep the water level at the high water level, take measures to deoxidize the boiler, and then isolate the pot water from the outside. After the helium or ammonia gas is introduced, the pressure after inflation is maintained at 0.2-0.3 MPa, and nitrogen and oxygen combine to form nitrogen oxide, so that the oxygen cannot be in contact with the steel plate; the ammonia is dissolved in water to make the water alkaline, and can be effective. Prevent the occurrence of oxygen corrosion.

Modular boilers refer to the connection of multiple boilers through joint control, according to the re-set heating demand curve and other parameters, and referring to the indoor and outdoor temperature difference, the system can carry out the number of boilers on/off intelligently, to realize the automatic adjustment operation mode. Modular boilers are widely used in many areas such as residential district heating and hot water supply, as well as industrial enterprise production. After two or more boilers are jointly controlled, the number of running boilers can be adjusted according to user needs. For example, if the residential building needs to adjust the supply temperature according to the seasons to adjust the number of running boilers, the industrial enterprises will adjust the number of running boilers depending on the quarterly workload and other factors.

When you purchase boiler equipment, you will pay attention to many problems, how much thermal efficiency, whether it is energy-saving and environmental protection, whether boiler manufacturers have special equipment installation and manufacturing certificates, etc., are the key points you need to pay attention to. At the same time, it is also important that the boiler is regularly maintained during use.

The gas boiler with regular maintenance can effectively extend the service life of the boiler, improve the working efficiency of the boiler, and reduce the incidence of failure, which is conducive to the normal and safe operation of the boiler. Gas-fired boilers that are regularly maintained have better service life, energy savings and failure rates than boilers that are not regularly maintained (especially those that have been in operation for more than one year).

Commonly used boiler maintenance methods are: pressure maintenance, wet maintenance, dry maintenance, and aeration maintenance.

First. pressure maintenance.
      Pressure maintenance is required when the boiler is not to be used for less than one week. Before the shutdown process is terminated, the steam water system is filled with water, the residual pressure is maintained at 0.05~0.1 MPa, and the temperature of the boiler water is maintained above 100 °C, which can effectively prevent air from entering the boiler.

Second. wet maintenance.
       Wet maintenance is required when the shutdown time is less than one month. Fill the boiler soda system with soft water containing lye, no steam space left. This is because an aqueous solution having an appropriate alkalinity forms a stable oxide film with the metal surface to prevent corrosion.

Third. dry maintenance.
       This method is used for maintenance when the boiler is stopped for a long time. The specific method is: after the boiler is shut down, the pot water is drained, the boiler is dried by left heat, and the residual scale and residue in the pot are removed in time, and then the tray containing the desiccant is placed in the drum and on the grate. Finally close all valves, manholes and hand hole doors. Regularly check the maintenance and replace the failed desiccant in time.

Fourth. aeration maintenance.
       Aeration maintenance can be used for long-term shutdown maintenance. After the boiler is shut down, do not release water, keep the water level at the high water level, take measures to deoxidize the boiler, and then isolate the pot water from the outside. After the helium or ammonia gas is introduced, the pressure after inflation is maintained at 0.2-0.3 MPa, and nitrogen and oxygen combine to form nitrogen oxide, so that the oxygen cannot be in contact with the steel plate; the ammonia is dissolved in water to make the water alkaline, and can be effective. Prevent the occurrence of oxygen corrosion.

Refer to auxiliary machine configuration, the water treatment will be placed in the first place. What is the meaning of water treatment?

Simply speaking, boiler water treatment refers to pre-softening the water flowing into the boiler and then flowing into the boiler for related use.

Natural water contains various salts. These salts are dissolved in cations and anions, mainly composed of calcium and magnesium ions, and are collectively referred to as "hard water". The minerals contained in these hard water boiled in the container and gradually form a white block or powdery solid, which is called "scale".

There are three major hazards in scale.
       1. Due to the extremely poor thermal conductivity of scale, heat absorption is reduced during heating, boiler thermal efficiency is reduced, fuel utilization is reduced, and boiler operating costs are increased.
        2. Fouling will cause the temperature of the furnace wall to increase exponentially. The stress of the steel is destroyed and the strength is reduced. In severe cases, the bursting phenomenon will occur, which will seriously reduce the service life of the boiler.
        3. The calcium and magnesium ions in the water will be integrated into the water during the heating process, which will directly affect the steam quality. At the same time, if the boiler parts such as safety valves, pressure gauges and pressure controllers are scaled, it will cause blockage.

Water treatment method.
       Boiler water treatment usually uses a combination of a resin tank and a salt tank. When the raw water containing calcium and magnesium ions passes through the resin layer of the exchanger, calcium ions and magnesium ions in the water are adsorbed by the resin while releasing sodium ions. The water that flows out of the exchanger is the demineralized water from which the hardness ions are removed. When the resin adsorbs a certain amount of calcium and magnesium ions, it must be regenerated. In the regeneration process, the resin layer is washed with a high-concentration sodium oxide solution in the salt can, and the hardness ions on the resin are replaced, and the resin is restored to the softening exchange function as the recycled waste liquid is discharged out of the tank.
         On-site practice:
       1. Check the inlet water pressure (0.2-0.4MPa); check whether the high-concentration brine in the pipe is sufficient; check whether the salt pipe and the sewage pipe are blocked; if there is any abnormality, start it after cleaning.
         2. Close the tap water bypass valve.
       3. Open the salt water inlet pipe valve and open the outlet pipe valve; open the demineralized water to the soft water tank manual and electric valve.
        4. The control valve is energized and the cycle water quantity parameter is set.
        5. start running.

Sometimes the boiler will suddenly have some conditions and face the emergency shutdown. Based on past experience, we have summarized the situation and treatment measures of boiler emergency shutdown to help you better understand the boiler.

First, emergency shutdown is required when the following conditions occur.
       1. The steam pressure exceeds the allowable safety pressure. After taking the natural gas supply, strengthening the water supply and reducing the wind, the pressure is still rising.
        2. the boiler is short of water, the water level table has not shown the water level, the water level is still not visible when the steam drum level valve is closed or the water supply is increased.
       3. The boiler is full of water and the water level has risen to the highest visible water level, but no visible water level appears after the water is released.
        4. All water level gauges or pressure gauges cannot be used normally.
        5. All safety valves and drain valves cannot be used normally.
       6. Boiler pressure parts, such as drums, furnace tubes, water wall tubes, etc., are damaged, when it is dangerous for people and equipment.
       7. The water supply equipment is faulty and there is no spare equipment.
       8. When there is a crack in the furnace wall, there will be collapse danger.
       9. The induced and forced draft fan are damaged and cannot continue to run.
       10. Other events seriously threaten the safe operation of the boiler.

Second, emergency shutdown process steps.
       1. Quickly turn off the heat treatment. First stop the burner, and close the natural gas supply valve to stop the supply of gas, then cut off the total air valve, and finally open the air valve or safety valve to exhaust steam and reduce precipitation.
       2. Rapidly cool the furnace water treatment. Do not continue to feed water into the boiler after the furnace has been shut down.
     When there is no water shortage or water leakage, the cooling time can be shortened, the cooling rate can be accelerated, and the water level can be lowered and lowered by the alternate method of water ingress and discharge.
     When the boiler is in a serious water shortage state, it is not allowed to adopt rapid cooling method. It is strictly forbidden to continue to supply water to the boiler, otherwise there is a risk of explosion.
      When the boiler is in full water state, it should weaken the combustion (the fire is considered to be changed into a small fire), open the drain valve to release the water, and open the steam trap on the main steam pipe and the sub-cylinder to prevent the steam from taking a lot of water and causing water washing.
       3. During the process of stopping the furnace, the furnace cooling rate should not be too fast, so as to prevent damage to the components such as flue, pressure parts and expansion ports due to sudden cooling.

With the elimination and transformation of large-scale coal-fired boilers, “coal to gas” and “coal to electricity” have become popular transformation methods. The electric boiler is clean, environmentally friendly and pollution-free, which helps to promote China's energy conservation and environmental protection policies, which can bring many benefits to both the country and the individual. For power consumption of electric boilers, it has become one of the most concerned issues for users. So, how can electric boilers be more energy efficient in use? FANGKUAI Boiler will share with you this knowledge.

Reasons for the large power consumption of electric boilers
       1. The house insulation effect is poor
       If the poor insulation effect of the room where the electric boiler is installed will directly lead to temperature loss, if you want to reach the predetermined temperature, you can only debug the boiler to reach a higher temperature to make up for the lost temperature, which will waste more energy.
       2. The house is much higher
    When the the house is much higher, the area of heat sharing will be larger, so that to achieve a higher indoor temperature, it is necessary to adjust to a higher indoor temperature.
       3. Unreasonable geothermal laying
      When the floor heat is laid, the insulation layer under the geothermal pipe is too thin (less than 3 cm), or the plane above the geothermal pipe is too thick (more than 5 cm). The heat does not conduct well, directly causing the loss of heat, so that the electric boiler needs to provide more heat.
       4. Electric boiler can not do intelligent regulation
      Some electric boilers are not equipped with intelligent control equipment. They need to be manually regulated during operation, and the operation steps are complicated and cannot be adjusted in time according to temperature requirements.

The electric boiler produced by FANGKUAI Boiler is mainly composed of boiler body, electric control box and intelligent control system. It can be fully automatic after power supply, and the user can adjust the running state according to the demand of temperature. The direct thermal heating tube is used in the structural design, which is convenient for replacement and maintenance.

For more information on electric boilers, you can contact the us directly via an online telephone.