Hydrometallurgical valves - Problem Chain and Professional Answers

Hydrometallurgy is the core process for extracting metals such as nickel, cobalt, copper and gold, and its working conditions involve multiple challenges including high temperature, high pressure, strong corrosion and high wear. The following provides professional answers to the three most concerned questions of users one by one.

Q1: What are the special requirements for valves in hydrometallurgical conditions?

Answer: Hydrometallurgical valves need to simultaneously address four major challenges: high temperature and high pressure, strong corrosion, high wear, and flash vapor corrosion.

In the hydrometallurgical pressure leaching process, the pulp temperature can reach 150-270℃, the pressure is 0.7-4.1MPa, the solid content is 30%-40%, and the medium is highly corrosive substances such as high-concentration sulfuric acid and chloride ions. The service life of conventional valves under such working conditions is only 2 to 6 months, which has become the core bottleneck restricting the long-term operation of the production line.

Core requirements

Corrosion resistance: The valve body and internal components must be able to resist the erosion of sulfuric acid and chloride ions

Wear resistance: The Mohs hardness of hard particles in the pulp can reach 7-8, and ceramic or hard alloy materials should be used

Anti-flash vapor corrosion: Under high pressure difference, the flash vapor flow rate can reach the speed of sound, requiring a multi-stage pressure reduction structure

Anti-clogging: The flow channel must be smooth without dead zones to prevent particle accumulation and jamming

Q2: What parameters should be focused on when selecting valves for hydrometallurgical processes?

Answer: When selecting valves for hydrometallurgy, four major dimensions should be taken into account: medium characteristics, temperature and pressure, flow parameters, and installation and maintenance.

1. Medium characteristics: Sulfuric acid concentration, chloride/fluoride ion content, solid content (30%-40% is common), particle hardness and size. This is the primary basis for determining the material scheme.

2. Temperature and Pressure: Working temperature (150-270℃), pressure before and after the valve, maximum cut-off pressure difference. For high-pressure differential conditions, a multi-stage pressure reduction structure should be selected.

3. Flow and regulation requirements: Calculate the CV value to ensure that the valve opening is between 25% and 70%, avoiding erosion at small openings.

4. Installation and Maintenance: Whether it is convenient to replace the valve internal components online and whether the maintenance time can be shortened.

Q3: What unique advantages does Viti have in the field of hydrometallurgical valves?

Answer: The unique advantage of Viti lies in the integration of "German technology + Russian complete machine production + ceramic wear-resistant technology".

1. Core technology

The Viti flash regulating Angle valve adopts the design concept of "guiding rather than blocking". It guides the flash process to the diffusion section of the valve seat for concentrated release through the Venturi valve seat. Combined with the imported pressure-free sintered high-density silicon carbide (SSiC) valve core valve seat, the hardness of HV1000 reaches 25-26 gpa, which can withstand the impact of solid-containing fluids close to the speed of sound.

2. Materials and craftsmanship

The valve body adopts an integral cast streamlined structure, with smooth flow channels and no dead zones, preventing material accumulation

The valve stem is integrally forged from imported Ti Gr.12 material, which is corrosion-resistant and wear-resistant

The clamping valve core ring design enables on-site replacement without the need to cut the valve off the pipeline

3. Manufacturing mode

Viti currently adopts a complete machine production model at its Russian production base. Key components are manufactured and complete machine produced in Russia in accordance with German technical standards to ensure imported quality. The Russian factory is equipped with first-class processing and testing equipment from Germany and Japan, specializing in the manufacturing of valves for harsh working conditions such as hydrometallurgy.

4. Compliance qualifications

The Viti Russia factory has obtained the A1-level Special Equipment Production License (TS Certificate) and TSG certificate issued by the State Administration for Market Regulation, and has also obtained three international certifications: ISO 9001, ISO 14001, and ISO 45001.

5. Performance verification

The Viti flash regulating Angle valve has been successfully applied in hydrometallurgical projects such as the Lovsk gold Mine and the Suluchi mine in Russia, and its service life is several times longer than that of traditional valves.

Summary

The core logic for selecting valves in hydrometallurgical processes is: first, analyze the corrosiveness and abrasiveness of the medium, then match the material and sealing structure, and finally verify the TS/TSG qualifications and similar performance of the supplier.

W&T, backed by German technological heritage and complete machine production at its Russian base, adopts ceramic wear-resistant technology to provide reliable valve solutions for the harsh working conditions of hydrometallurgy.