Purification device
The present invention aims to provide a compound purification apparatus capable of providing a high purity compound in high yield and at low cost. The present invention relates to an apparatus for purifying a compound, the purification apparatus including: a crystallizing unit including a crystal forming section; and a wash column including a mechanism that forcibly transfers crystals, the crystallizing unit including N tanks connected in series, wherein N is 2 or greater, a 1st tank is a most downstream tank, a (N)th tank is a most upstream tank, at least the 1st tank is a crystallization tank including a cooling mechanism, and a 2nd and subsequent tanks are each a crystallization tank or a ripening tank, the purification apparatus including a line that feeds a compound-containing liquid to be purified to at least one of the N tanks, the wash column including: a line that sends a product out; and a line that returns a mother liquor to the crystallizing unit, with the line that returns a mother liquor to the crystallizing unit being connected to at least the (N)th tank, the crystallizing unit including: a line that feeds a slurry from the (N)th tank to the wash column; a line that sends a slurry from a tank among the 1st to (N−1)th tanks to the next upstream tank; and a line that is provided to each of the 1st to (N−1)th tanks and that sends thereto a mother liquor withdrawn from an upstream tank, wherein at least one of the lines that send a slurry from a tank among the 1st to (N−1)th tanks to the next upstream tank is a line that sends a slurry from a tank to the next upstream tank via a solid-liquid separator and that has a line that returns a mother liquor from which crystals are removed in the solid-liquid separator to the tank where the slurry came from, and wherein the line that is provided to each of the 1st to (N−1)th tanks and that sends thereto a mother liquor withdrawn from an upstream tank is a line that directly sends a mother liquor withdrawn from a tank one upstream or a line that sends a mother liquor withdrawn from a tank one upstream via a solid-liquid separator, the purification apparatus further including a line that sends a mother liquor to the outside of the purification apparatus.
1 . An apparatus for purifying a compound, the purification apparatus comprising:
a crystallizing unit including a crystal forming section; and
a wash column including a mechanism that forcibly transfers crystals,
the crystallizing unit including N tanks connected in series, wherein N is 2 or greater, a 1st tank is a most downstream tank, a (N)th tank is a most upstream tank, at least the 1st tank is a crystallization tank including a cooling mechanism, and a 2nd and subsequent tanks are each a crystallization tank or a ripening tank,
the purification apparatus including a line that feeds a compound-containing liquid to be purified to at least one of the N tanks,
the wash column including:
a line that sends a product out; and
a line that returns a mother liquor to the crystallizing unit, with the line that returns a mother liquor to the crystallizing unit being connected to at least the (N)th tank,
the crystallizing unit including:
a line that feeds a slurry from the (N)th tank to the wash column;
a line that sends a slurry from a tank among the 1st to (N-1)th tanks to the next upstream tank; and
a line that is provided to each of the 1st to (N-1)th tanks and that sends thereto a mother liquor withdrawn from an upstream tank, and
a line that returns a mother liquor from the wash column to the (N)th tank of the crystallizing unit without passing through any other crystallization tank or ripening tank,
wherein at least one of the lines that send a slurry from a tank among the 1st to (N-1)th tanks to the next upstream tank is a line that sends a slurry from a tank to the next upstream tank via a solid-liquid separator and that has a line that returns a mother liquor from which crystals are removed in the solid-liquid separator to the tank where the slurry came from, and
wherein the line that is provided to each of the 1st to (N-1)th tanks and that sends thereto a mother liquor withdrawn from an upstream tank is a line that directly sends a mother liquor withdrawn from a tank one upstream or a line that sends a mother liquor withdrawn from a tank one upstream via a solid-liquid separator,
the purification apparatus further including a line that sends a mother liquor to the outside of the purification apparatus.
2 . The purification apparatus according to claim 1 ,
wherein each of the 1st to (N-1)th tanks in the crystallizing unit includes a line that sends a slurry from a tank to the next upstream tank via a solid-liquid separator and a line that returns at least a portion of a mother liquor discharged from the solid-liquid separator to the tank where the slurry came from.
3 . The purification apparatus according to claim 1 ,
wherein at least one of the lines that are provided to the 1st to (N-1)th tanks and that send thereto a mother liquor withdrawn from an upstream tank is a line that sends a mother liquor withdrawn from a tank one upstream via a solid-liquid separator.
4 . The purification apparatus according to claim 1 ,
wherein at least one of solid-liquid separators each provided in a line that sends a slurry from a downstream tank to an upstream tank includes a line that returns a mother liquor to the tank where the slurry came from, and at least one additional line that sends a mother liquor,
wherein the at least one additional line is connected to a tank that is downstream from the tank where the slurry came from and/or to the outside of the purification apparatus.
5 . The purification apparatus according to claim 1 ,
wherein at least one of the 1st to (N-1)th tanks in the crystallizing unit includes a line that directly sends a mother liquor withdrawn from a tank one upstream.
6 . The purification apparatus according to claim 1 , further comprising a line that sends a mother liquor from the 1st tank in the crystallizing unit to the outside of the purification apparatus via a solid-liquid separator.
7 . The purification apparatus according to claim 1 ,
wherein the cooling mechanism is of a type that contents of the tank are cooled outside the tank.
8 . The purification apparatus according to claim 1 ,
wherein the wash column includes a mechanical mechanism that scrapes off a crystal bed.
9 . The purification apparatus according to claim 1 ,
wherein the wash column does not include a mechanical mechanism that scrapes off a crystal bed.
10 . The purification apparatus according to claim 1 ,
wherein the compound is (meth)acrylic acid.
11 . The purification apparatus according to claim 1 ,
wherein in the crystallizing unit, at least a line that sends a slurry from the (n-1)th tank to the (N)th tank among lines that send a slurry from a tank to the next upstream tank is a line that sends a slurry from a tank to the next upstream tank via a solid-liquid separator, and
wherein the solid-liquid separator in the line that sends a slurry from the (n-1)th tank to the (N)th tank is a basket centrifuge or a decanter centrifuge.
12 . The purification apparatus according to claim 1 , wherein the (N)th tank included in the crystallization apparatus has a larger capacity than any of the downstream tanks, and further wherein the (N)th tank has a structure in which the mother liquor is overflowed and directly sent to the downstream tanks.