FILTER AIDS

LOW DENSITY = SAVINGS

  Humid density Kg/sack

Perfiltra's perlite

6 - 11

 12 / 61

Other perlites

 10 - 13 18 / 20

Diatoms

 23 27 / 24

 

As shown in the chart, Perfiltra's perlite is lower in humid density. One kilograme of such perlite will span a larger volume than other perlites or any diatom, which directly translates into a reduction in costs because filter aids are trade per unit of weight and used per unit of volume.


After expanding perlite, it is processed and classified to obtain 8 different degrees of additional filters. These meet the flow clarification-speed combinations that may be required by the various industries.
While filters are traded in the market per their weight, during the filtering process, filter aids are used per their volume, that is, their volume is what really matters, not their weight. Since Perfiltra's filter aids brand is very low in density, significant savings may be obtained, which are over 25% with respect to other perlites and up to 35% with respect to diatoms.

 
Some frequent uses
Wine Juices
Water Acids
Sider Molasses
Syrups Antibiotics
Alcohols Beers
Agar-agar Electroplating
Glucose - fructose Vegetable oils

 

 Properties 
 Chemical 
 SiO2  76  Fe2O3  0.3  MgO  0.04  Sulfates  free
 AI2O3  17  CaO  0.44  Na2O  2  Orgánic mat.  free

 

 Physical
 

degrees
   170  200  320  272  332 443  634  734  800  950

 Color

 white white white white white white white white white white

 pH

  6 - 8  6 - 8  6 - 8  6 - 8  6 - 8  6 - 8  6 - 8  6 - 8  7.6  7.6

 Maximum
humidity (1)

  5-8  4-5 2.8-3.2 2.0-2.2 1.8-2.0 1.55-1.80 1.4-1.55 1.0-1.4 0.8-1.0 0.3-0.5

 Reteined in 325 screen(1)

  >80 76-80 57-67 55-65 50-60 47-57 40-50 35-45 3-7 <5

Humid density (2)

 95/115 100/120 135/165 145/175 145/175 150/175 160/175 160/175 168/175 168/175

(1) weight percentage     (2) expressed in kg/m

How to use it

Filtration, which is the separation of solids from liquids, is one of the most commonly used operations in industrial processes. When systems contain low quantities of solids and resistance to filtration is high, filter aids are of primary importance to achieve an efficient and economical filtration. In this way, during the filtering process, the filtering means especially serves as support for the adobe roughcast. The filter aids forms a porous layer onto the filtering means, which mainly serves as support for the adobe roughcast formed by the solids to be divided. In this way, the filter aids traps solids, thus clarifying the liquid and protecting the filtering means from sealing.
Due to this mechanism, the volume spanned by the filter aids is important since such volume will form the porous layer taking part in filtration.
filter aids may be used in two ways:

In pre-layers: they are applied to an filter aid layer on the filter screen through which suspension to be filtered flows. A thickness of 1.5 to 3 mm may be used (for pressure filters), and, for doing so, from 200 to 500 grams of filter aid are required per square meter of the filtering area. The best flow speed during the pre-layer formation varies from 40 to 60 liters per minute and per square meter by using water.
Pre-layers ranging from 50 to 100 mm are used in rotary filters. For purposes of stiffening this thickness, suspension of an filter aid ranging from 2 to 6% is pumped into the filter (in weight).

In dosage: the addition of such filter to a liquid before it is sent to the filter is known as dosage. The quantity to be dosed depends on each application, ranging from 0.1% to 1% of the suspension weight, being able to reach up to 8% in the event of solids which filtration is difficult (colloids, compressible solids, etc.).

 

Permeability

 


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