Continuous Washing of High-Solid Slurries

The washing and solid-liquid separation of high-solid-content slurries has long been a process pain point in the chemical, metallurgy and new energy materials industries. As slurry solid content rises, system viscosity increases exponentially, and conventional plate-and-frame filtration, sedimentation or centrifugation easily lead to problems such as incomplete washing, high water consumption, easy filter cloth clogging and the inability to achieve continuous production.

Relying on deep expertise in ceramic membrane material development and membrane integration technology, Jiuwu Hi-Tech has provided a standardized breakthrough solution through an integrated membrane process. Centred on "cross-flow filtration" and "counter-current displacement", the solution achieves efficient continuous impurity removal under high-solid conditions while greatly reducing washing water consumption.

Industry Status: The Challenge of Separating High-Solid-Content Materials

To reduce costs and increase efficiency, enterprises continue to raise reaction concentrations, leading to substantial increases in slurry solid content and system viscosity. Facing such materials, conventional plate-and-frame or centrifugation processes expose three major problems:

High water consumption, high cost: Conventional rinsing consumes enormous amounts of water, and the massive saline wastewater generated greatly increases the energy consumption and equipment load of downstream evaporation treatment.

Dead zones, easy residue: High filter cake resistance causes washing water to form "short circuits", creating internal washing dead zones where impurities cannot be thoroughly displaced, affecting product purity.

Easy clogging, difficult to run continuously: Extremely fine particles easily block filter cloth pores, requiring frequent shutdowns for cleaning or manual cake discharge, unable to meet the demands of automated continuous production.

The Jiuwu Solution: Four Steps to Continuous Impurity Removal Washing

Addressing the separation challenge of high solid content and high viscosity, Jiuwu Hi-Tech uses inorganic ceramic membranes as the core and adopts "cross-flow filtration" and "counter-current displacement" technologies, standardizing the process into four steps:

1. Pre-treatment and slurry conditioning

High-solid-content slurry (solid content 20%-40%) enters a buffer tank and is continuously dispersed by a specific stirring device to prevent particles with higher specific gravity from settling, ensuring uniform material concentration entering the membrane system.

2. Cross-flow concentration

The material is pumped into the ceramic membrane module and flows at high speed parallel to the membrane surface. Under pressure, interstitial water and soluble salts pass through the membrane pores, while the high-speed fluid scours the membrane surface, preventing particle adhesion and completing initial slurry concentration.

3. Multi-stage counter-current washing

Multi-stage membrane modules operate in series: the low-concentration permeate from the later stage is used as make-up water for the earlier stage, with fresh water added only at the final stage. The washing liquid and slurry are force-mixed and then filtered, displacing internal salts.

4. Product collection and recovery

Slurry that meets the washing target is pumped directly to downstream stages such as drying or centrifugation. The discharged high-concentration permeate is collected centrally and reused for slurry preparation or sent to the evaporation crystallization system.

Process Advantages and Material Adaptability

Through the above process design, Jiuwu Hi-Tech's membrane continuous washing process has changed the handling of high-solid-content slurries in three dimensions:

Lower water and energy consumption: Thanks to the cascade circulating counter-current washing mode, the system's overall washing water consumption is reduced by 40% to 60%, with a proportional reduction in steam consumption of the downstream wastewater evaporation system.

Higher purity, no dead zones: Dynamic cross-flow scouring and online mixing thoroughly break the "water short-circuit" phenomenon of conventional filter cakes; the washing liquid fully contacts microscopic particles, with soluble impurity removal above 99.5%.

Closed-loop, continuous and stable operation: The core ceramic membranes (alumina / zirconia material) feature high mechanical strength, high pressure resistance and resistance to acid and alkali corrosion; the entire system can withstand the pressure of high-viscosity materials, achieving 24-hour enclosed continuous operation without frequent manual dismantling and cleaning.

Through its integrated membrane process system, Jiuwu Hi-Tech has solved the solid-liquid separation obstacles in the washing of high-solid, fine-particle slurries at the fluid level. Based on actual factory operating data, this technology reduces water resource consumption and labour costs for relevant producers, improves production line continuity and finished product impurity control, and provides a standardized process route for the separation and purification of complex fluids.