Firstly, an introduction to sponge iron deaerator

The fully automatic room temperature sponge iron filter type deaerator uses sponge iron filter type as the filter material, and is equipped with both manual and fully automatic deaeration devices. The tank body is designed with a unique double backwash structure, which allows the reactants and trapped substances in the filter material to be fully flushed out. The boiler feed water has strict requirements, first of all, it needs to be softened or desalinated to prevent scaling inside the heating surface of the boiler. However, water still contains oxygen and other gases. Oxygen is a major depolarizing agent that can cause corrosion on the metal surfaces of boiler equipment and thermal systems. This corrosion is often localized ulcer corrosion, which can cause metal wall perforation in severe cases. It not only greatly shortens the life of boiler equipment, but also affects the safety of boilers and thermal systems. In order to ensure the safe and economical operation of boilers, the "Low pressure Boiler Water Quality Standard" (GB1576-85) issued by the state stipulates that all boilers with a rated evaporation capacity greater than 2T/H must be treated with deoxygenation equipment.

Secondly, the working principle of sponge iron deaerator

Room temperature filtration deoxygenation belongs to chemical deoxygenation, which uses specially produced active sponge iron filtration (direct reduction of iron) to remove dissolved oxygen from water. The main component of sponge iron filtration is iron, and its loose and porous internal structure provides a specific surface area that is 50000 to 100000 times that of ordinary iron filings. It can cause rapid and thorough oxidation reaction between oxygen and iron in water, stabilizing dissolved oxygen below 0.05mg/L. Its reaction formula is:

2Fe2++2H2O+O2 → 2Fe (OH) 2 4Fe (OH) 2+2H2O+O2 → 4Fe (OH) 3

The reaction products Fe (OH) 2 and Fe (OH) 3 are flocculent precipitates that are not easily soluble in water. When they pass through other sponge iron filter particles with water flow, they are intercepted and can be washed clean with a certain strength of backwash water flow (about 5 minutes).

The consumption of sponge iron filtration is very low, and it can be replenished every 3-6 months depending on the amount of treated water and water quality.

After deoxygenation, a small amount of iron ions are added, usually 0.2-0.5mg/L, which still meets the national water quality standards for hot water boilers. However, for steam boilers or feedwater deoxygenation with strict requirements for Fe2+, iron removal devices can be installed to remove Fe2+from the water. Our company has various specifications of ion exchange iron removal devices for users to choose from. )

The sponge iron filtration type, as a water deoxygenation agent, uses Fe3O4 powder with a particle size of -200 mesh or less to bond together, with a particle size of about 2-5mm. Due to the displacement reaction during its reduction process, a certain number of voids are formed, as well as voids during the bonding of powder particles, making the pores of the deoxidizer extremely high and the specific surface area large. Moreover, because it is directly reduced from primary ore and relatively pure, its activity is extremely high, and it reacts with oxygen in water to produce Fe3O4, thereby achieving the purpose of deoxidization. At the same time, the utilization rate has also been increased to over 90%.

Moreover, due to the presence of a certain amount of impurities, the particles can only form weak bond connections during the deoxygenation process, and they basically do not rust and die into clusters. After being used by multiple units, the effect of this product is very ideal. The oxygen content in the effluent is reduced to below 0.05mg/L, and only about 25g is consumed per cubic meter of water, truly achieving high-quality and low-cost operation.

Due to the fact that water without softening can easily passivate the surface of the deoxygenation agent, slowing down its oxidation and affecting the deoxygenation effect, it should be softened first before deoxygenation. After using for a period of time, it should be backwashed.

　　Thirdly, the technical characteristics of Zhongtian Jingyuan sponge iron deaerator

The technology and working principle used in sponge iron filter deaerator have the following characteristics:

Deoxygenation can be achieved at room temperature, and the inlet water does not require heating;

The system can supply water at any time without preparation time or the need for a deoxygenated water tank;

The deoxygenation effect is stable and reliable, and the dissolved oxygen content in the effluent is stable at ≤ 0.05mg/L, which meets the water quality standards for low-pressure boilers;

There are no special requirements for installation, overcoming the inconvenience of high-level installation for thermal and vacuum deoxygenation;

The equipment can be arranged in a low position, with a simple process and no high height requirements.

Fourthly, the characteristics of sponge iron deaerator products

The new type of sponge iron filter deaerator has been introduced in China for several years. The early designed equipment structure and process have gradually exposed some shortcomings in actual operation, sometimes causing significant impact on system operation. Based on the practical experience of several users and addressing the shortcomings of early design, our company adopts a new design concept, original imported components, and advanced control technology to design and produce a sponge iron filter deaerator with the following characteristics:

The process is simpler and more reasonable, the equipment structure is simple and compact, and easy to operate and maintain;

The control automation level is high, and the system can automatically backwash according to time or working pressure loss without manual operation. Timely backwashing eliminates the agglomeration of deoxidizer, reduces water consumption, and keeps the equipment in good working condition at all times;

The equipment adopts a dual tank structure or a single tank dual chamber structure, which can continuously produce water. If the inlet pressure is sufficient, there is no need to interrupt the water production even during backwashing, making the operation of the downstream system more stable and reliable;

The equipment automatically uses anaerobic water for backwashing, further improving the backwashing effect and reducing water and oxygen consumption.

The automation system has extremely low power consumption and is equipped with manual operation devices. The backwash operation can be carried out with just one button.

Fifth, process principle flowchart

The process flow of sponge iron filtration deoxygenation system is simple and clear. The following explanation is for reference only:

1. It is recommended that the inlet pressure of the softening system be greater than 0.35MPa, so that the softened water can directly enter the deaerator. The process is as follows:

2. When the inlet pressure of the softener is less than 0.25MPa, the water pressure after softening is lower. If it is lower than 0.15MPa, it may not meet the backwash requirements of the filter type deaerator, and a booster pump should be added. The following process can be adopted:

Sixth, pictures of sponge iron filter deaerator equipment