GEA ふん尿処理用デカンタ

What is a manure Decanter?

A manure decanter is a specialized decanter centrifuge designed for the continuous solid-liquid separation of liquid manure and fermentation residues (digestate) from dairy farms, breeding farms, and biogas plants. Unlike gravity separation or screening technology, a decanter centrifuge uses centrifugal force to efficiently remove solid particles from manure slurry, achieving superior separation efficiency compared to conventional screw press separators or filter presses.

The GEA manure Decanter is a horizontal solid-wall bowl centrifuge specifically engineered to address the challenges of modern manure management: reducing phosphate and nitrogen content to comply with fertilizer ordinances, minimizing storage capacities, and transforming waste into valuable resources such as natural fertilizer, compost, or feedstock for biogas plants.

How does a Decanter work?

Decanter centrifuges operate on the principle of centrifugal separation. Here's how the separation process works in a GEA manure Decanter:

1. Feed: Manure slurry or digestate is continuously fed into the rotating bowl via a stationary feed pipe.
2. Centrifugal force: The bowl rotates at high bowl speed (typically 3,000–4,000 rpm), generating centrifugal forces up to 3,000 times gravity. This force drives heavier solid particles to the bowl wall.
3. Solid conveyance: A scroll inside the bowl rotates at a differential speed relative to the bowl, transporting the settled solids toward the conical discharge end.
4. Liquid Clarification: The clarified liquid phase (centrate) flows in the opposite direction and is discharged over adjustable weirs, ensuring optimal liquid-solid separation.
5. Discharge: Dewatered solids exit as a stackable cake (20–35% dry matter), while the liquid phase – now significantly reduced in suspended solids – can be reused for irrigation, returned to storage capacities, or further treated in wastewater treatment plants.

The entire process is PLC controlled, enabling fully automated operation with minimal manual intervention. The GEA manure Decanter requires no chemical flocculants or polymers for standard applications, reducing operational costs and environmental impact.