What Is a Clarifier
A clarifier is a device used to separate solutions in which different substances are mixed and to extract the clear liquid (clarified liquid).
It is specifically used for solutions in which solids and liquids are mixed.
Since centrifugal force during rotation is used for separation, additives such as flocculants do not need to be added. Since there is no need to add anything extra, it is cost-effective and economical. It is also possible to suppress the deterioration of the solution.
By changing the speed of rotation, the clarifier can handle a variety of solutions, and the quality of the clarified solution can be freely changed.
Uses of Clarifiers
Here are some examples of clarifier applications.
1. Water Purification Equipment
Clarifiers are used in water purification systems in settling ponds.
Dirty water arrives at the settling pond. Dirty water contains mud and bacteria, and foreign matter must be removed to make the water clean.
Clarifiers allow foreign matter to settle out and clean water to be extracted. The extracted water is disinfected and transported to homes and facilities.
2. Foods
A typical example is milk. It is used to remove debris and bacteria from milk.
It is also used to remove oil from whey.
Principle of Clarifiers
Clarifiers use centrifugal force to separate solutions when the device is rotated.
Centrifugal force is the inertial force generated when the device is rotated. The inertial force causes an outward force in the direction of rotation. The outward force generated pulls heavy objects (solids) and makes them easier to settle.
Centrifugal force is affected by the rotation speed and the distance from the center of rotation to the object (rotation radius), and the larger the rotation speed and rotation radius, the greater the centrifugal force.
Although spontaneous sedimentation, in which the solution is simply left to settle, can be used for separation, it takes a long time to separate the solutions because they are sedimented by the force of gravity alone.
Sedimentation using a clarifier requires several thousand times the gravitational acceleration of natural sedimentation, making separation possible in a shorter time.
There are different types of clarifiers, the most typical of which are the separation plate type and the cylindrical type. Among them, they are finely divided.
The appropriate shape differs depending on the target solution and the degree of removal of clarified liquid. It is necessary to use it according to the purpose.