# Horizontal Decanter Centrifuge for Fermentation Broth Clarification and Solid-Liquid Separation

Fermentation engineering is one of the core production technologies in modern biological industry, covering functional enzyme preparations, microbial active substances, amino acids, biological peptides and fermentation polysaccharides. After the completion of strain fermentation and cultivation, the original fermentation broth is a heterogeneous mixed system. The liquid phase contains target active metabolites such as enzymes, amino acids and polysaccharides, while the solid phase includes a large number of dead bacteria, active mycelium, broken cell debris, residual solid medium and suspended colloidal particles. If these solid impurities are not completely removed in the early stage, they will cause liquid turbidity, unstable quality and difficult subsequent refining, seriously affecting the purity, activity and shelf stability of finished biological products.

Traditional fermentation broth separation processes have obvious technical drawbacks and cannot adapt to modern large-scale biological production. Static sedimentation requires a long standing cycle, occupies a large number of tank equipment, and is easy to cause microbial re-proliferation and oxidative deterioration of active substances, resulting in reduced product activity. Plate-and-frame filter presses and belt filtration equipment rely on filter cloth interception, which requires frequent manual cleaning and replacement of consumables, resulting in high labor costs and low production efficiency. In addition, filter cloth shedding and incomplete interception of fine cell debris will cause secondary contamination of the filtrate, reducing the purification accuracy and final product yield.

The horizontal decanter centrifuge perfectly solves the common pain points of traditional fermentation liquid pretreatment. Based on the principle of density difference centrifugal sedimentation, the high-speed rotating drum forms a strong centrifugal force field. High-density mycelium particles, bacterial residues and cell debris rapidly settle to the inner wall of the drum. Under the push of the differential spiral, the solid slag is continuously discharged out of the machine, while the clarified fermentation liquid flows out stably from the liquid outlet to realize automatic continuous slag-liquid separation.

The whole separation process adopts fully enclosed low-shear operation, which effectively avoids liquid splashing, foam generation and active ingredient oxidation. Different from intermittent traditional filtration, the decanter centrifuge supports 24-hour uninterrupted feeding, separation and slag discharge, realizing continuous assembly-line production. By adjusting the rotating speed and differential speed, the equipment can flexibly adapt to different fermentation broth viscosity, mycelium density and solid content, ensuring stable separation effect for various microbial fermentation materials.

In standardized biological fermentation production lines, the decanter centrifuge is arranged as the primary clarification equipment before membrane refining and concentration. It removes more than 99% of mycelium slag and suspended particulate impurities in the fermentation broth, greatly reducing the impurity load of subsequent ultrafiltration and nanofiltration systems. Thorough removal of biological slag can effectively reduce membrane fouling frequency, extend membrane service life, stabilize the flux of membrane system, and significantly reduce the operating and maintenance costs of downstream fine refining processes.

Compared with traditional processes, centrifugal separation has no need for filter aids and disposable filter materials, eliminating solid waste generation and secondary pollution. The fully automatic control system realizes intelligent operation, reduces manual intervention and improves batch production consistency. The separated clear fermentation liquid has high purity and stable activity, which is conducive to improving the recovery rate of biological active ingredients and increasing enterprise economic benefits. The separated solid mycelium residue can also be comprehensively recycled and utilized to realize resource recycling.

With the continuous upgrading of the biological fermentation industry and the improvement of clean production standards, efficient, continuous and green solid-liquid separation technology has become an indispensable supporting process for fermentation product deep processing. The horizontal decanter centrifuge provides a reliable and efficient pretreatment solution for modern fermentation enterprises, helping enterprises achieve high yield, high purity and low-consumption intelligent production.