Scraper Bottom Discharge Centrifuge for High-Chloride Salt Crystal Recovery

The Scraper Bottom Discharge Centrifuge is designed for batch dewatering, cake washing, and automatic bottom discharge of salt crystals recovered from high-chloride brine, evaporator concentrate, and crystallization mother liquor.

It is suitable for sodium chloride, potassium chloride, chloride-rich mixed salts, and other filterable crystals produced in high-salinity process streams. The centrifuge separates chloride-containing mother liquor from the crystal cake, reduces retained liquid through centrifugal drying, and automatically discharges the recovered salt through the bottom outlet.

Peony provides the solid-liquid separation section for high-chloride salt recovery after concentration, evaporation, and crystallization.

Evaporator / Crystallizer → Crystal Slurry Tank → Controlled Feeding → Scraper Bottom Discharge Centrifuge → Mother Liquor Recycle or Purge → Optional Cake Washing → Automatic Bottom Discharge → Dryer / Cooler / Screen / Storage

The configuration can include:

• Corrosion-resistant wetted material selection
• Crystal slurry buffer tank and agitator
• Stable and controlled slurry feeding system
• Filter basket and filter cloth selection according to crystal size
• Optional cake washing for reduced mother liquor carryover
• Filtrate collection and mother liquor recycle connection
• Automatic scraper discharge system
• PLC control with batch sequence and safety interlocks
• Connection to dryer, vibrating screen, cooling system, conveyor, silo, or packaging line
• Optional enclosed structure for corrosive or high-humidity operating environments

1. High-Chloride Crystal Slurry Feeding

Crystal slurry from the evaporator, crystallizer, or slurry tank is fed into the rotating basket through a controlled feed system.

Stable feeding is important to maintain even cake formation and avoid excessive crystal breakage.

2. Mother Liquor Filtration

Under centrifugal force, chloride-rich mother liquor passes through the filter medium and basket perforations.

The separated liquid is collected through the filtrate outlet and can be returned to the crystallization system, transferred to a mother liquor tank, or routed to a purge and recovery section.

3. Crystal Cake Formation

Salt crystals are retained inside the basket and gradually form a filter cake on the basket wall.

The cake permeability depends on crystal size, fines content, crystal shape, slurry solids concentration, and liquor viscosity.

4. Optional Cake Washing

A controlled wash liquid can be introduced to reduce chloride-rich mother liquor retained between crystals.

This step is useful when the recovered salt requires lower impurity carryover before drying, screening, storage, or further refining.

5. Centrifugal Spin Drying

After filtration and washing, the basket continues rotating to reduce free liquid remaining in the salt cake.

Lower retained mother liquor can reduce the drying load and improve downstream product handling.

6. Automatic Scraping and Bottom Discharge

At the end of the batch cycle, the scraper removes the dewatered salt cake from the basket wall.

Recovered salt crystals are discharged automatically through the bottom outlet and transferred to the next process stage.

Designed for High-Chloride Process Liquor

The centrifuge can be configured according to chloride concentration, operating temperature, pH, oxidizing conditions, and mother liquor chemistry.

Material selection is determined by actual process data rather than using a standard stainless-steel configuration by default.

Improved Salt Recovery from Mother Liquor

The filtration and spin-drying process separates recoverable crystals from high-chloride mother liquor, helping reduce salt loss to purge streams or wastewater treatment.

Lower Mother Liquor Carryover

Centrifugal dewatering reduces retained chloride-rich liquid in the cake before downstream drying, cooling, screening, or packaging.

Optional Cake Washing

An in-basket washing system can reduce mother liquor residues, soluble impurities, and unwanted salt carryover where product quality requires a cleaner crystal surface.

Automatic Bottom Discharge

The scraper discharge system removes the salt cake automatically, reducing manual handling and improving operating consistency in corrosive salt processing areas.

Can the centrifuge recover sodium chloride crystals from high-chloride brine?

Yes. It can be configured for sodium chloride crystal recovery when the slurry contains filterable crystals capable of forming a stable cake. The final configuration should be based on chloride concentration, temperature, crystal size, solids concentration, and mother liquor chemistry.

Is SS316L suitable for high-chloride salt crystal recovery?

SS316L may be suitable for selected applications, but it should not be assumed to be sufficient for all high-chloride environments. Higher chloride concentration, elevated temperature, oxidizing conditions, acid cleaning, and stagnant liquor zones may require a higher-grade material configuration.

Can the separated mother liquor be recycled?

Yes. The filtrate can be returned to an evaporator, crystallizer, mother liquor tank, brine concentration section, or controlled purge stream according to the salt recovery process.

Can salt crystals be washed inside the centrifuge?

Yes. An optional cake washing system can be installed to reduce residual mother liquor and soluble impurities on the recovered crystals. The wash liquid and washing sequence should be confirmed based on the product specification and salt solubility.

Can the centrifuge connect directly to a dryer?

Yes. The automatic bottom discharge can be connected with a dryer, fluidized bed cooler, vibrating screen, belt conveyor, screw conveyor, storage silo, or packaging system.