Centrifuge Operation and Scraper Centrifuge Separation Time Control

Operation steps for industrial centrifuge

When using the fully automatic industrial centrifuge, the centrifuge should first run empty. During the process of empty operation, follow the steps below:

1. Turn on the power air switch in the electrical control box.

   
   

2. Press the "medium speed" button by hand to run the centrifuge with no load. When the centrifuge gradually runs from stationary to "medium speed", pay close attention to whether there is abnormal vibration or abnormal noise. If there is any abnormality, stop the machine in time for inspection and elimination.

   
   

3. Press the "high speed" button by hand. The centrifuge will gradually accelerate from medium speed to high speed (the time is set by the frequency converter). At the same time, pay close attention to whether there is any abnormal vibration or abnormal noise. If there is any abnormality, stop the machine in time for inspection and elimination.

   
   

4. Press the "low speed" button by hand. The centrifuge will run from high speed to low speed. After reaching the scraping speed, the scraper operation can be carried out.

   
   

5. Press the "stop" button. The operation process of the centrifuge stops.

Separation time control for scraper centrifuge

The scraper centrifuge is a filter centrifuge with intermittent operation of the scraper lower discharge. It integrates a number of high-tech technologies, such as PLC or computer touch screen program control, variable frequency drive, electrical braking, RF inductive material level detection, controllable multiple automatic feeding, special feeding device. It can achieve uniform and smooth feeding and washing, customized damping and vibration reduction device, and can be applied to closed, explosion-proof occasions. The whole process can be divided into five stages. The motor drives the drum to revolve around the main shaft axis through the transmission system, forming a centrifugal force field, reaching the feeding speed, which can be called the start-up process.

The separated suspension enters the drum from the feeding pipe, is thrown towards the drum wall under the action of centrifugal force, which is called the feeding process. The liquid phase is thrown to the shell space through the filter net on the drum wall and the drum wall filter hole at a higher speed, and is collected in the chassis, and then discharged through the drainage pipe. The solid phase remains inside the filter cloth, which is called the dewatering process. If the material needs to be washed, the washing water is added through the washing pipe, which is called the washing process. After dewatering, the drum runs at low speed, then the compressed air is turned on, and the scraper rotates into the knife under the action of the cylinder piston, and the flat centrifuge moves down layer by layer to scrape the filter cake down, which is called the discharging process. After the discharging is completed, the scraper returns to the original position, the drum rises to the feeding speed, and the next cycle begins.

Several points for controlling the separation time of the scraper centrifuge:

• Under the same centrifugal force conditions, the separation time is inversely proportional to the difference in density of the separated substance in the test liquid. The larger the density, the shorter the separation time, and the smaller the density, the longer the separation time.

• In the same test solution, the separation time is inversely proportional to the centrifugal force. The larger the centrifugal force, the shorter the separation time, and the smaller the centrifugal force, the longer the separation time.

• The separation time of the scraper centrifuge is related to the minimum centrifugal radius. A longer suspension basket (test bottle) requires a longer separation time.

Therefore, the separation time of the scraper centrifuge is not fixed and difficult to calculate.

The separation process of scraper centrifuge includes the following stages:

• Mixing and accelerating stage: the slag-containing wastewater and flocculant are mixed and accelerated in the feeding chamber to ensure that the slag-containing wastewater enters the separation zone in the best state.

• Clarification stage: under the action of centrifugal force, the flocculation particles are rapidly separated and settled in the straight line section of the drum, and the separated clear liquid is discharged through the weir at the tail end of the drum.

• Compression stage: the spiral pusher pushes the settled solid to the discharge end. The sludge is further compressed under the action of centrifugal force and releases pore water.