HEDP Hydroxyethylidene Diphosphonic Acid Industrial Water Treatment Applications

HEDP (1-Hydroxy Ethylidene-1,1-Diphosphonic Acid) plays a vital role in industrial water treatment. The following is a detailed analysis of HEDP in industrial water treatment:

I. Chemical properties of HEDP

• Molecular formula: C2H8O7P2
• Molecular weight: 206.02
• Appearance: white crystalline powder or transparent liquid
• Solubility: soluble in water, soluble in alcohol and other organic solvents
• Stability: stable in a wide range of pH, high temperature resistant.

Second, the functional properties of HEDP

1. Scale inhibition performance:

• HEDP can form stable complexes with metal ions in water (e.g. calcium, magnesium, etc.), thus inhibiting these metal ions from combining with anions in water (e.g. carbonate, sulfate, etc.) to form insoluble scale.
• The molecular structure of HEDP contains a number of phosphonic acid groups, which can interact with the suspended particles in the water and the tiny scale particles that have been formed, improve the dispersion of the particles in the liquid, and prevent them from aggregating into larger scale pieces.
• HEDP can be adsorbed on the crystal growth point of scale-forming ions, interfering with their normal crystal growth pattern, resulting in the formation of a loose and fragile scale structure, which is not easy to adhere to the surface of the equipment.

Corrosion inhibition performance:

• HEDP can form a protective film on the metal surface, inhibiting the occurrence of cathodic reaction (such as the precipitation of hydrogen) and anodic reaction (such as the dissolution of metal ions), thus slowing down the corrosion rate of the metal.
• This protective film also physically shields the metal surface from the direct contact of corrosive media (e.g., oxygen, acids, etc.) with the metal.
• HEDP may also change the electrochemical environment of the metal surface, such as through the formation of a stable oxide film or change the potential, thereby inhibiting the corrosion reaction.

Third, the application of HEDP in industrial water treatment

HEDP is widely used in industrial circulating cooling water system of electric power, chemical industry, metallurgy, chemical fertiliser, etc., as well as scale and corrosion inhibition of medium and low pressure boiler, oil field water injection and oil pipeline. Specifically:

1. Circulating cooling water system: HEDP can effectively prevent the scaling of inorganic salts such as calcium carbonate and calcium sulphate, and keep the system clean and efficient operation.
2. Boiler water treatment: HEDP can prevent scale formation, improve thermal efficiency and extend the service life of boiler.
3. Oil field water injection and oil pipeline: HEDP can reduce the scale in oil wells and pipelines, and guarantee the smooth production.

Fourth, the environmental protection of HEDP

HEDP is relatively easy to biodegradation, friendly to the environment, and suitable for occasions with high requirements for environmental protection. In addition, HEDP can also be used to treat wastewater containing heavy metal ions, reduce the concentration of heavy metal ions in wastewater to meet environmental emission standards.

V. Precautions for HEDP

1. Compatibility: Before adding HEDP to the water treatment system, it is necessary to ensure its compatibility with other water treatment chemicals to avoid unnecessary chemical reactions.
2. Dosage control: the correct dosage is to ensure that HEDP to play the best effect of the key, too much or too little will affect the treatment effect. As a scale inhibitor _, the general use of _{110mg/L, as a corrosion inhibitor, the general use of 1050mg/L concentration}.
3. Safety: When storing and using HEDP, you should follow the safety operation procedures, avoid direct contact with skin and eyes, and take appropriate protective measures.