FAQs for Decanter Centrifuge
1
FAQs for Decanter Centrifuge
Q: What is the difference between 2-phase and 3-phase decanter centrifuges, and what working conditions are they suitable for respectively?
A: A 2-phase decanter separates solid and one single liquid phase, which applies to sludge dewatering, grain lees treatment, starch residue dehydration, etc. A 3-phase decanter can separate solid, light liquid (oil) and heavy liquid (water) simultaneously, ideal for oily wastewater, waste cooking oil, ship bilge water and edible oil refining. We can provide free separation solutions based on your material samples.
Q: How does differential speed affect separation performance?
A: Differential speed refers to the rotational speed difference between the bowl and scroll, which controls solid residence time inside the machine. Higher differential speed leads to faster solid discharge with higher cake moisture content; lower differential speed extends material residence time to achieve drier cake but may cause blockage. Our equipment is equipped with dual frequency conversion to realize adjustable differential speed to cope with fluctuating feed concentration.
Q: What causes high cake moisture and turbid clarified liquid, and how to adjust the machine?
A: There are four common reasons: 1. Excessive feed flow leading to insufficient material residence time; 2. Overhigh differential speed setting; 3. Improper flocculant dosage; 4. Worn wear tiles on scroll. Corresponding solutions: reduce feed rate, moderately lower differential speed, optimize chemical dosage, and replace tungsten carbide wear tiles by factory service.
Q: The unit runs with severe vibration, can we keep it in continuous operation?
A: Continuous operation under heavy vibration is strictly prohibited, as it will damage bearings and gearbox. Root causes include uneven solid accumulation caused by fluctuating feed solid content, loose anchor bolts, aging bearings and unbalanced scroll. Solutions: stop the machine to clean the bowl thoroughly, fasten the base, inspect and replace faulty bearings, and redo dynamic balance for scroll.
Q: Can the decanter centrifuge operate automatically 24 hours a day? What control system is equipped as standard?
A: The whole machine is designed for 24/7 non-stop continuous operation, equipped with standard PLC and HMI touch screen automatic control system. It monitors real-time data including rotating speed, torque, bearing temperature, vibration and current. The system supports automatic alarm and shutdown under overload, over-temperature and excessive vibration, as well as automatic differential speed adjustment for unattended running.
Q: How to select proper material grade? What upgraded options are available for food, chemical and explosion-proof working conditions?
A: 304 stainless steel is adopted for general materials; 316L or duplex 2205 stainless steel for highly corrosive chemical media; mirror-polished sanitary 316L for food and pharmaceutical industries. For flammable and explosive sites, the explosion-proof version with Ex d II BT4 rated motor and control cabinet is optional, and CE & EAC-Ex certificates can be provided.
Q: What is the service life of core wearing parts? What is the regular maintenance cycle?
A: Tungsten carbide wear tiles have a normal service life of 8,000–12,000 hours; the design service life of main bearings reaches 15,000 hours. Gearbox lubricating oil shall be replaced every 2,000 operating hours. Daily inspection covers vibration, temperature and oil pressure; full bowl cleaning is required every six months. We offer a 12-month warranty for the whole machine.
Q: The machine is blocked and no solid is discharged from the slag outlet, how to handle the emergency?
A: Cut off feed and stop the machine immediately. Flush the interior of the bowl with clean water while jogging the unit at low speed to clear accumulated solids completely. Never force startup under blockage. An optional DN50 flushing pipeline can be installed for automatic cleaning during startup and shutdown to prevent blockage.
Q: What documents will be delivered together with the machine? Is FAT and SAT acceptance available?
A: Production will be completed within 50 days after receiving advance payment. Supplied documents include assembly drawings, P&ID diagrams, operation & maintenance manuals, material certificates, CE and EAC-Ex certification documents. Factory Acceptance Test (FAT) is available at our workshop. After delivery, our engineers can be dispatched to site for Site Acceptance Test (SAT), installation, commissioning and operator training.
Q: How to confirm the proper model specification (processing capacity, bowl diameter) for my project?
A: Three key parameters are required for accurate model selection: hourly total feed flow rate, solid content of feed material, and target cake moisture. We provide free laboratory sediment tests to match suitable bowl length-diameter ratio, G-force and power, and issue a complete quotation with full technical parameters.
Copyright © 2026 Shenzhou Machinery is a core subsidiary of Shenzhou Group | Sitemap