Huading Centrifuge Secondary Extraction Okara Washing Skid Maximizing Soy Protein Recovery

In a conventional soy milk line the okara leaving the primary decanter still carries between 8 and 15 percent of the protein that entered the process. That protein is not lost because it cannot be extracted, it is lost because there is no economical way to wash it out of the fibre. The Huading LW450D two stage system provides that way: a primary decanter separates the okara, the cake is re-slurried with water, and a second decanter presses the washed fibre to recover the dilute protein solution for return to the main stream.

Plants using this configuration routinely lift overall protein recovery from the mid 70s into the low 90s, which converts directly into more soy milk from the same tonnage of beans. The two stages run under a single PLC that balances wash water ratio against cake dryness, so the operator sets a recovery target and the system holds it while feed conditions drift.

• Above 92 percent protein recovery: washing the okara in counter current stages returns the soluble protein to the product stream, adding measurable yield without extra raw material.
• Two decanters, one control philosophy: a single PLC coordinates feed splitting, wash water dosing, differential speeds and cake dryness across both stages, removing the guesswork of manual washing.
• Tunable wash ratio: the operator sets 2 to 4 parts water per part okara, balancing water consumption and evaporation load against the marginal protein recovered.
• Consistent washed cake: the second stage presses the re-slurried fibre to below 68 percent moisture, keeping the okara light for transport and stable for feed use.
• Reduced BOD load: recovering protein from the fibre lowers the organic load in wash water and reduces the cost of downstream effluent treatment.
• Hygienic and drainable: both machines use radiused, fully drainable casings and food grade contact materials, allowing fast cleaning between production campaigns.
• Proven modular build: the two decanters, slurry tank, dosing pump and control panel are delivered as a pre piped module that fits beside an existing extraction line.

Primary decanter stage one receives the cooked soy slurry and separates okara from soy milk, discharging cake into the wash tank. There the cake is re-slurried with metered wash water and pumped to stage two, where the second decanter separates the dilute protein solution from the washed fibre. The dilute solution is returned to the primary feed, while the washed okara leaves as a low moisture cake. The PLC watches density and flow and adjusts water dosing and differential speed to hold the recovery target.

This system suits soy milk and tofu plants, soy protein concentrate lines, and beverage factories producing soy, rice, oat and nut milks where soluble solids remain trapped in the fibre after primary separation. It is also used to recover solids from fruit pulp wash and from starch fibre streams.

The module ships as two plywood cases for the decanters plus a crate for the wash tank, dosing pump and control panel, all with rust preventive treatment and internal bracing. Documentation covers P and ID drawings, electrical schematics, PLC backup, operating procedures, spare parts lists and material certificates, together with a commissioning checklist for the two stage loop.