Performance indicators of walnut shell filter media and precautions for use

Characteristic parameters of general walnut shell filter media
Test items Test data Test items Test data Oil removal rate 90-95% Backwash strength 25 Suspended solids removal rate 95-98% Water flushing pressure 0.32mpa Filtration speed 20-25m/h Maintenance method 5-10% replenishment every year Density 1.25 g /cm3 Bulk density 0.8 g/cm3
Parameters of Meiqi Industry and Trade Walnut Shell Filter
Filter material type Walnut shell is suitable for water purposes. Water filtration performance is acid-resistant, alkali-resistant, high-temperature resistant, and low-temperature resistant. High-efficiency brand Hengchang adsorption rate 98 (%) pressure resistance 0.32 (kgf) density 1.5 (g/cm3) porosity 96 ( %) Abrasion rate 0.35 Hardness 95 Chemical composition Walnut shell hydrochloric acid soluble rate 0.35 (%)
(1) The number of possible contacts between suspended particles and a filter layer of unit thickness is proposed. The number of suspended particles retained by the filter layer has a positive relationship with the number of contacts;
(2) The smaller particle size of the walnut shell filter material is beneficial to ensure the quality of the filtered water, but it may cause the water flow shear force and the head loss to increase too fast, resulting in low pollution content of the filter layer, short filtration cycle, low filtration speed, and water production. Small problems, generally not conducive to filtering
(3) Under the condition of ensuring the quality of the filtered water, it is advisable to choose a walnut shell filter material with a larger particle size;
(4) The thickness of the filter layer increases as the particle size of the walnut shell filter material increases;
(5) The smaller the average particle size of the walnut shell filter material, the larger the unevenness coefficient can be, the larger the average particle size of the walnut shell filter material, the smaller the unevenness coefficient;
(6) Increasing the porosity of the filter layer is beneficial to the filtration process, but the porosity of the walnut shell granular filter material is mainly determined by the arrangement of the filter material particles under the premise of uniform particle size, and has little relationship with the particle size .