Effect Of Precoating On Filtering Effect Of Wedge Wire Diatomaceous Earth Filter
- Before beer filtration, the operation of depositing a layer of effective filter additives on the wedge wire screen diatomite filter element is called precoating. The purpose of precoating is to prevent impurity particles from blocking the filter screen and to obtain satisfactory clarity at the beginning of filtration.
- The greater the precoating amount, the better the kneading effect and the higher the clarity of the wine residue. However, the excessive precoating amount will affect the total amount of filter aid, shorten the filtration cycle and reduce the total amount of filtered wine. Therefore, it is very important to have a reasonable proportion of precoating, precoating amount, and fine soil.
- The first layer of precoating shall use Ying soil to support the second layer and avoid fine soil blocking the screen.
- After the circulating water of the first layer is clear, apply the second layer.
- The second layer is precoated with diatomite additives mixed in thickness (the thickness ratio is generally 1:1) to form an efficient filter layer and effectively intercept suspended particles and colloidal impurities. The thickness of precoating is generally about 3M and the precoating time is about 20 minutes.
- During precoating, the flow rate should not be too fast to avoid bubbles and uneven coating. After precoating, clean water can continue to reflux for 5-10 minutes to make the coating adsorb more firmly and prolong the filtration cycle.
- The addition of filter aid must be appropriate to ensure both high filtration accuracy and appropriate filtration speed. If the dosage is too large, the frame will be filled prematurely, resulting in shortening the filtering cycle and reducing the total filtering amount. If the addition amount is insufficient, the resistance will increase and the pressure will rise rapidly, resulting in the reduction of filtration efficiency and even affecting the service life of paperboard.
- Therefore, the addition proportion and quantity of additives must be adjusted at any time according to the concentration of impurity particles in the liquor. Only in this way can we not only ensure the liquor filtering accuracy but also prolong the liquor filtering cycle, improve the total amount of liquor filtering and improve the service life of wedge wire screen diatomite filter element.
Influence Of Adding Method And Amount Of Filter Aid On Filtering Effect Of Diatomite Wedge Wire Filter
- In the process of liquor filtering, the operation of continuously adding diatomite additives to the liquor to be filtered according to the concentration and properties of Jingfu particles and colloidal impurities contained in the liquor to be filtered is called adding additives. Its function is to make the filter aid particles form a mixed filter with ketone substances and impurity particles, so as to reduce the compressibility of the filter cake. In addition, the expanding “bridge structure” can not only improve the space of the filter cake, but also continuously update the filter bed, so as to keep the filtration fast and stable, and finally improve the filtration efficiency and periodic filtration capacity.
- The addition of filter aid must be appropriate to ensure both high filtration accuracy and appropriate filtration speed. As a result, the filtration cycle is shortened and the total amount of filtration is reduced. If the addition amount is insufficient, the resistance will increase and the pressure will rise rapidly, resulting in the reduction of filtration efficiency and even affecting the service life of the wedge wire filter element.