Preparation method for iron phosphate powder by microporous filtration and concentration and preparation device thereof

A preparation method for iron phosphate powder by microporous filtration and concentration, wherein the preparation method is applied to a preparation device for iron phosphate powder by microporous filtration and concentration;

• the preparation device for iron phosphate powder by microporous filtration and concentration comprises
• a reactor (1) and a filter concentrator (2);
• a slurry circulating tube (4) with a slurry circulating valve (3) and a feed tube (6) with a feed valve (5) are arranged between the reactor (1) and the filter concentrator (2);
• the filter concentrator (2) comprises a filtration and concentration tank body (7);
• an inner cavity of the filtration and concentration tank body (7) is provided with a stirring shaft (8) connected with a motor;
• the stirring shaft (8) is provided with an upper stirring blade (9) and a lower stirring blade (10) arranged up and down;
• a plurality of upper microporous filtration tube groups (11) and a plurality of lower microporous filtration tube groups (12) arranged on one side of an inner cavity of the filtration and concentration tank body (7) corresponding to the upper stirring blade (9) and the lower stirring blade (10) respectively;
• an upper liquid inlet end of the upper microporous filtration tube groups (11) is located above the upper stirring blade (9), and an upper liquid inlet end of the lower microporous filtration tube groups (12) is located between the upper stirring blade (9) and the lower stirring blade (10);
• lower liquid outlet ends of the upper microporous filtration tube groups (11) and the lower microporous filtration tube groups (12) are provided with a blowback and recoil tube (13) and a filtrate tube (14) connected with the upper microporous filtration tube groups (11) and the lower microporous filtration tube groups (12) and extended to the outside of the filtration and concentration tank body (7);
• and the blowback and recoil tube (13) and the filtrate tube (14) are respectively provided with a blowback and recoil valve (15) and a filtrate valve (16);
• the preparation method comprises:
• (1) putting raw materials into the reactor to react for nucleation,
• (2) a mother liquor generated after raw materials reaction entering the filter concentrator,
• (3) controlling and starting of the stirring shaft for driving the upper stirring blade and the lower stirring blade to rotate for grinding and scaling;
• (4) when a mother solution level exceeds the upper liquid inlet end of the lower microporous filtration tube groups, controlling and starting the filtrate valve of the filtrate tube of the lower microporous filtration tube groups, and
• (5) when the mother solution level exceeds the upper liquid inlet end of upper microporous filtration tube groups, controlling and starting of the filtrate valve of the filtrate tube of the upper microporous filtration tube groups;
• (6) after the filtrate valves of the filtrate tubes of the upper microporous filtration tube groups and the lower microporous filtration tube groups are all started, turning on and turning off the filtrate valves of the upper microporous filtration tube groups and the lower microporous filtration tube groups successively with a same period of time, and
• (7) during each period, a group of the upper microporous filtration tube groups or the lower microporous filtration tube groups is in a state of restarting and discharging the filtrate;
• and
• (8) returning the filtered slurry into the reactor through the slurry circulating tube to continue to grow crystals, and extracting iron phosphate powder from a solid product.