1. Process Background and Core Challenges

In the wet smelting process of rare metals such as molybdenum, tungsten, cobalt, nickel, etc., chemical precipitation (usually pH adjustment to generate hydroxides) is a key step in separating and purifying the target metal. The filtration and washing effects of the hydroxide precipitation slurry produced in this process are directly related to:

• Metal recovery rate: The mother liquor carried in the filter cake contains valuable metals that have not precipitated, and the washing efficiency determines the recovery rate..

• Product purity: Impurity ions mixed in the hydroxide filter cake (such as NaE, ClE, SOE²); ⁻, etc.) must be removed by thorough washing, otherwise it will affect the grade of the final metal product or chemical product (such as molybdenum trioxide, ammonium paratungstate, electrolytic cobalt/nickel).

• Production cost and environmental compliance: This process faces many severe challenges:

Pain points of traditional filtration equipment (such as plate frames and ordinary vacuum filters) in this scenario:

• High material value, fatal loss: Hydroxide precipitation is mostly in the form of gel or fine particles, with serious filtration and leakage phenomena, causing direct loss of precious metals..

• Strong corrosive environment: The precipitation process is usually carried out under strong acidic or strong alkaline conditions, and the slurry is highly corrosive to equipment, shortening its service life..

• The washing requirements are extremely high: a large amount of efficient washing is needed to replace the mother liquor. Traditional equipment has uneven washing, high water consumption, and low efficiency.

• Environmental and occupational health pressure: Stimulating and harmful gases such as ammonia and acid mist may be generated during the process, and open operation can harm employee health and pollute the environment..

• Low degree of automation: High labor intensity, and manual operation is prone to introduce pollution, affecting product consistency..

2. Solution Core: XU Fully Sealed Vacuum Filter

2.1 Design Concept
Zhejiang Hexu Machinery XU Fully Sealed Vacuum Filter provides a set of solutions to the above challenges.; “ Fully enclosed, efficient washing, corrosion-resistant and wear-resistant, resource recycling;   The integrated solution aims to achieve ultra-high recovery rate, ultra-high purity, intrinsic safety, and clean production.

2.2 Core Technical Principles of Zhejiang Hexu Machinery XU Fully Sealed Vacuum Filter

• Fully enclosed negative pressure operation: The entire filtration, washing, and unloading process is carried out in a completely enclosed system, with stable driving force provided by a vacuum pump.. This not only prevents the leakage of harmful gases, but more importantly, it prevents the atomization, volatilization, and dust dispersion of valuable materials.

• High efficiency multi-stage countercurrent washing: After the filter cake is formed, multi-stage (such as 3-5 stages) high-efficiency countercurrent washing can be carried out in a closed system. Using a small amount of high-quality washing solution (such as pure water, dilute ammonia water, etc.), through spraying and permeation, the impurity content in the filter cake is gradually reduced, and the washing efficiency is increased by more than 30% compared to traditional equipment.

• Targeted material selection: Components that come into contact with materials can use advanced stainless steel (such as 316L), Hastelloy alloy, titanium, or polypropylene (PP)/PTFE liningbased on process characteristics (pH value, chloride ion concentration, etc.) to fundamentally solve corrosion problems..

• High precision filtration guarantee: Adopting high-precision and leak free filter element design, it ensures that fine hydroxide particles are completely intercepted, effectively solving the problem of“ Filter” Problem, ensure the recycling rate.

2.3 Zhejiang Hexu Machinery XU Fully Sealed Vacuum Filter System Integration Process

[leachate]→ [Neutralization precipitation]→ [Hydroxide slurry]→ [XU Fully Sealed Filter Core Unit]→ [Pure Hydroxide Filter Cake]→ [Downstream smelting/roasting] ↓ (Efficient countercurrent washing) [Washing wastewater]→ [Wastewater treatment/valuable component recovery] ↓ [Vacuum System]→ [Gas liquid separator]→ [Condenser]→ [Exhaust Gas Purification Tower]→ [Standard emissions] ↓ [Recycled ammonia/acid mist condensate]→ [Reuse to Process]

3. The core value of Zhejiang Hexu Machinery's XU fully sealed solution

• 3.1 Ultimate Economic Benefits: Improved Recovery and Purity

  • Maximizing Recovery: Closed systems and precision filtration minimize mechanical losses of metals, and are expected to increase system recovery rates by 0.5% -1.5%. For high-value rare metals, the economic benefits are enormous..

  • Product purity leap: Efficient countercurrent washing ensures extremely low impurity content in the filter cake, laying a solid foundation for the production of high-purity metals (such as cobalt and nickel above 4N5) and significantly increasing product prices..

  • Reduce subsequent costs: The low and uniform moisture content of the filter cake significantly reduces the energy consumption of subsequent roasting or smelting..

• 3.2 Intrinsic Safety and Green Environmental Protection

  • Gas“ Zero” Evacuation: A completely enclosed operating environment that allows harmful gases such as ammonia and acid mist to be 100% collected and processed, achieving clean production and easily responding to environmental inspections.

  • Wastewater reduction and resource utilization: Counter current washing itself is a water-saving process, and the concentration gradient of the washing wastewater produced is distinct, which facilitates targeted recovery or treatment of valuable components..

• 3.3 Automation and Stability

  • Full process PLC/DCS control, achieving one click operation and online monitoring (such as filter cake thickness and washing solution pH), ensuring batch stability and reducing human intervention, is a step towards“ Intelligent Metallurgy” The crucial step.

  • The equipment runs stably and has a long maintenance cycle, providing reliable support for continuous large-scale production.

4. Detailed explanation of typical metal application scenarios

• Scenario 1: Precipitation filtration of calcium molybdate/iron molybdate (extracting molybdenum from molybdenite roasting dust)

  • Challenge: The sediment particles are fine and viscous, traditional filtration is prone to clogging, and molybdenum loss is severe..

  • XU Solution: Fully enclosed to prevent molybdenum dust loss, stable high vacuum degree overcomes filter cake resistance, efficient washing and removal of soluble impurities, providing high-quality raw materials for subsequent ammonia leaching preparation of ammonium molybdate.

• Scenario 2: Cobalt hydroxide/nickel hydroxide precipitation filtration (deep purification and purification from cobalt/nickel solution)

  • Challenge: The product has extremely high value and strict requirements for impurities (such as zinc and copper) content; Co/Ni hydroxide is a gel like substance that is extremely difficult to filter and wash.

  • XU Solution:

    • Using specially designed pre coated layers or filter aid systems to prevent colloid from filtering through.

    • Multi stage hot water or dilute alkaline solution washing thoroughly removes impurities and ions, and can directly produce battery grade precursor materials.

    • The entire process is sealed, preventing the product from being contaminated by the environment.

• Scenario 3: Filtration of precursors of synthetic scheelite (synthesized calcium tungstate) or ammonium paratungstate (APT)

  • Challenge: Extremely strict requirements for impurities such as phosphorus, arsenic, and silicon in the product; Tungsten has a high value, and any loss is unacceptable.

  • XU Solution: Precise filtration ensures complete retention of microcrystals; The efficiency of countercurrent washing is extremely high, and it can achieve the purity index required by the process with the least amount of water, significantly reducing the load of wastewater treatment.

5. Investment Return Analysis

Taking an XU fully sealed filter machine for processing cobalt hydroxide as an example:

Project	Value Analysis
Equipment investment	Assuming XXX million yuan (depending on material and scale)
Annual metal recycling value	Due to a 0.8% increase in recovery rate, the annual additional value of cobalt metal recovered is approximately XX million yuan
Product Premium	Due to the increase in purity, the selling price of the product has increased by YY yuan per ton, with an annual appreciation of approximately ZZ million yuan
Saved washing water and wastewater treatment costs	Approximately 150000 to 300000 yuan per year
Saved energy consumption for subsequent roasting	About 100000 to 200000 yuan per year
Expected investment payback period	About 1-3 years (depending on processing scale and metal prices)

Conclusion: This equipment is not simply used in rare metal smelting.; Cost Center; But rather a powerful '; Profit Center; Its investment return is clear and substantial.

6. Our Service Commitment

We provide services from; “ Small/medium scale trial certification - Process package design - Customized material selection and manufacturing - Automation system integration - Installation and commissioning - Operation training - Lifetime maintenance”   Our full lifecycle services ensure the successful implementation and continuous creation of value for your project.

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Summary

In the high-tech and high-value field of rare metal hydrometallurgy, Zhejiang Hexu Machinery's XU fully sealed vacuum filter machine; It is the ultimate solution to the core problem of hydroxide precipitation filtration. It directly translates into higher metal recovery rates, better product quality, lower operating costs, and stronger environmental compliance through its unparalleled sealing, washing efficiency, and reliability. Choosing XU means choosing to embed a strong and reliable“ Craft Heart” To help you win the dual advantages of technology and economy in the fierce market competition.