TiO2 BASED SCRUBBING GRANULES, AND METHODS OF MAKING AND USING SUCH TiO2 BASED SCRUBBING GRANULES
TiO 2 based scrubbing granules, and methods of making and using such TiO 2 based scrubbing granules are described. TiO 2 -based scrubbing granules include granulated TiO 2 and about 0.5% to about 20% dry weight inorganic salt binder. Other TiO 2 based scrubbing granules include unsintered granulated TiO 2 and about 0.5% to about 20% dry weight inorganic salt binder. Inorganic salt binder include sodium aluminate. Methods of making TiO 2 based scrubbing granules include i) combining TiO 2 particles with inorganic salt binder to form TiO 2 -binder mixture comprising from about 0.5% to about 20% dry weight binder; ii) granulating the TiO 2 -binder mixture; and drying the granulated TiO 2 -binder mixture to form TiO 2 -based scrubbing granules. Methods of using such TiO 2 -based scrubbing granules include introducing TiO 2 -based scrubbing granules to remove adherent deposits on an inner surface of a reactor or heat exchanger during processes of forming TiO 2 particles and finishing the formed TiO 2 particles into finished pigment products.
1 . TiO 2 -based scrubbing granules comprising:
i. granulated TiO 2 ;
ii. sodium aluminate binder comprising from about 0.5% to about 20% by dry weight of the TiO 2 -based scrubbing granules.
2 . TiO 2 -based scrubbing granules of claim 1 , wherein the TiO 2 -based scrubbing granules are dispersible in a TiO 2 slurry during a process of making finished TiO 2 pigment.
3 . TiO 2 -based scrubbing granules of claim 1 , wherein the TiO 2 -based scrubbing granules are unsintered.
4 . TiO2-based scrubbing granules of claim 1 , further comprising an inorganic salt.
5 . TiO 2 -based scrubbing granules of claim 1 , further comprising an inorganic metal salt selected from the group consisting of sodium sulfate, sodium phosphate, sodium silicate, sodium chloride, sodium hexametaphosphate, aluminum sulfate, and combinations thereof.
6 . TiO 2 -based scrubbing granules of claim 1 , wherein the TiO 2 -based scrubbing granules have an average size from about 1 mm to about 25 mm.
7 . A method of making TiO 2 -based scrubbing granules comprising:
i. combining TiO 2 particles with sodium aluminate binder to form a TiO 2 -binder mixture comprising from about 0.5% to about 20% dry weight binder; and
ii. granulating the TiO 2 -binder mixture;
iii. drying the granulated TiO 2 -binder mixture to form TiO 2 -based scrubbing granules.
8 . The method of claim 7 , wherein the binder further comprises an inorganic metal salt.
9 . The method of claim 7 , wherein the binder further comprises an inorganic metal salt selected from the group consisting of sodium sulfate, sodium phosphate, sodium silicate, sodium chloride, sodium hexametaphosphate, aluminum sulfate, and combinations thereof.
10 . The method of claim 7 , further comprising compacting the TiO 2 -binder mixture under pressure to form the TiO 2 -binder mixture into compacted briquettes.
11 . The method of claim 10 , further comprising breaking the compacted briquettes into TiO2-binder granules having an average size in a range of from about 1 mm to about 25 mm.
12 . The method of claim 7 , wherein drying the TiO 2 -binder mixture comprises heating at a temperature in a range of from about 100° C. to about 700° C.
13 . The method of claim 7 , wherein the TiO 2 particles are produced by a chloride or sulfate TiO 2 manufacturing process.
14 . The method of claim 7 , wherein the TiO 2 -based scrubbing granules are unsintered.
15 . A method comprising:
i. introducing TiCl 4 into a TiO 2 reaction zone of a reactor to form TiO 2 particles;
ii. introducing TiO 2 -based scrubbing granules into the reactor or a heat exchanger, thereby resulting in a TiO 2 product stream comprising the TiO 2 -based scrubbing granules and formed TiO 2 particles;
wherein the TiO 2 based scrubbing granules comprise:
a. granulated TiO 2 ; and
b. sodium aluminate binder comprising from about 0.5% to about 20% by dry weight of the TiO 2 -based scrubbing granules; and
iii. cooling the TiO 2 product stream via the heat exchanger, wherein the TiO 2 -based scrubbing granules in the TiO 2 product stream removes deposits on an inner surface of the heat exchanger as the TiO 2 product stream comprising the TiO 2 -based scrubbing granules passes through the heat exchanger.
16 . The method of claim 15 , wherein the introduced TiO 2 -based scrubbing granules are unsintered.
17 . The method of claim 15 , further comprising introducing TiO 2 -based scrubbing granules comprising an inorganic salt selected from the group consisting of sodium sulfate, sodium phosphate, sodium silicate, sodium chloride, sodium hexametaphosphate, aluminum sulfate, and combinations thereof.
18 . The method of claim 15 , further comprising recovering the cooled TiO 2 particles and TiO 2 -based scrubbing granules from the heat exchanger.
19 . The method of claim 18 , further comprising finishing the recovered TiO 2 particles into finished TiO 2 pigment via a wet finishing process.
20 . The method of claim 19 , comprising finishing the recovered TiO 2 particles by introducing the recovered TiO 2 particles and recovered TiO 2 -based scrubbing granules into a slurry tank to form the finished TiO 2 pigment.
21 . The method of claim 19 , further comprising not removing the TiO 2 -based scrubbing granules from the finished TiO 2 pigment.
22 . The method of claim 15 , further comprising introducing a nucleating agent to the TiO 2 reaction mixture before, during, or after the TiO 2 -based scrubbing granules are introduced.
23 . The method of claim 22 , wherein the nucleating agent comprises a salt or halide of a group IA metal.
24 . The method of claim 22 , wherein the nucleating agent is selected from the group consisting of potassium, cesium, and combinations thereof.
25 . The method of claim 22 , wherein the nucleating agent is selected from a group consisting of KCl, CsCl, and combinations thereof.
26 . The method of claim 15 , wherein the TiO 2 -scrubbing granules are free flowing.
27 . The method of claim 15 , further comprising altering a selected characteristic of the introduced TiO 2 based scrubbing granules in response to a change in a predetermined scrubbing efficiency.
28 . The method of claim 27 , further comprising increasing or decreasing the amount of introduced TiO 2 based scrubbing granules in response to a change in the predetermined scrubbing efficiency.
29 . The method of claim 15 , wherein the TiO 2 -based scrubbing granules are introduced in an amount in range from about 1% to 10% weight percent of the total TiO 2 production rate in the reactor.
30 . TiO 2 -based scrubbing granules of claim 1 , wherein the TiO 2 -based scrubbing granules have a bulk density in a range of from about 800 to about 1800 kg/m 3 .
31 . TiO 2 -based scrubbing granules comprising:
i. granulated TiO 2
ii. binder comprising from about 0.5% to about 20% by dry weight of the TiO 2 -based scrubbing granules; and
iii. wherein the TiO 2 -based scrubbing granules are unsintered.
32 . TiO 2 -based scrubbing granules of claim 31 , wherein the TiO 2 -based scrubbing granules are dispersible in TiO 2 slurry during a process of making finished TiO 2 pigment.
33 . TiO 2 -based scrubbing granules of claim 31 , wherein the binder comprises an inorganic metal salt selected from the group consisting of sodium aluminate, sodium sulfate, sodium phosphate, sodium silicate, sodium chloride, sodium hexametaphosphate, aluminum sulfate, and combinations thereof.
34 . TiO 2 -based scrubbing granules of claim 31 , wherein the binder comprises sodium aluminate.
35 . TiO 2 -based scrubbing granules of claim 31 , wherein the TiO 2 -based scrubbing granules have an average size in a range of from about 1 mm to about 25 mm.
36 . TiO 2 -based scrubbing granules of claim 31 , wherein the TiO 2 -based scrubbing granules have a bulk density in a range of from about 800 to about 1800 kg/m 3 .