CN110882552A

CN110882552A - Air stripping type DTB evaporative crystallizer

Info

Publication number: CN110882552A
Application number: CN201911256503.4A
Authority: CN
Inventors: 王斌
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-12-10
Filing date: 2019-12-10
Publication date: 2020-03-17

Abstract

The invention relates to the technical field of industrial crystallization, and discloses an air stripping type DTB evaporative crystallizer which comprises a crystallizer, a guide cylinder, a supersaturated feed liquid inlet, a solution outlet, a steam outlet and an elutriation column, wherein the guide cylinder extends into the crystallizer. Compared with the prior art, the invention leads gas into the crystallizer through the inflatable stirring device, drives the feed liquid to rotate and rise, increases the circulation rate of the gas, can increase the stirring of the feed liquid, increases the flow rate of the feed liquid, increases the nucleation and crystal growth efficiency of solute, effectively reduces the mechanical collision of the crystal, reduces the damage of the crystal, improves the quality of the crystal, and simultaneously can reduce the contact point and time of the inner wall of the inflatable stirring device due to the gas flowing out of the inflatable stirring device, effectively reduces the formation rate of crystal scale on the inner wall of the inflatable stirring device, reduces the maintenance times of instruments and reduces the maintenance cost.

Description

Air stripping type DTB evaporative crystallizer

Technical Field

The invention relates to the technical field of industrial crystallization, in particular to an air stripping type DTB evaporative crystallizer.

Background

The DTB evaporative crystallizer 1 is a fine-grained slurry circulating crystallizer 1, as shown in fig. 1, supersaturated feed liquid flows into the crystallizer 1 from a supersaturated feed liquid inlet 5, and is delivered to the liquid surface along a cylindrical baffle 3 by a slowly rotating stirring device 4, the supersaturated feed liquid is evaporated and cooled on the liquid surface, and reaches a supersaturated state, wherein a part of solute is deposited on the surface of suspended particles, so that crystals grow up, a settling zone is formed between the crystallizer 1 and a guide cylinder 2, large particles settle in the settling zone, small particles are discharged from a solution outlet 6 along with mother liquid, enter a circulating pipe and are heated and dissolved, and the crystals sink into an elutriation column 8 from the bottom of the crystallizer 1, but some defects exist in the crystallization process:

when agitating unit 4 stirs the feed liquid, when rotation rate is slower, stirring effect to the feed liquid is not good, can't make the feed liquid rise and accelerate feed liquid flow rate, when agitating unit 4 rotation rate is faster, its rotating blade causes the shearing collision to the crystal in the feed liquid, lead to the crystal breakage in the feed liquid, make the quality of crystal descend, stir the in-process simultaneously and make the feed liquid and the inner wall formation collision of cylindric baffle 3, increase feed liquid and cylindric baffle 3's area of contact, make the inner wall of cylindric baffle 3 very easily form crystal dirty, cause the inner space of cylindric baffle 3 to reduce, cause very big reduction to the flow of feed liquid.

Disclosure of Invention

The invention provides an air stripping type DTB evaporative crystallizer, which has the advantage of greatly increasing the crystallization rate and solves the problems in the background art.

The invention provides the following technical scheme: the utility model provides an air stripping formula DTB evaporative crystallizer, includes crystallizer, draft tube, supersaturated feed liquid import, solution outlet, steam outlet and elutriation post, the draft tube stretches into the inside of crystallizer, and forms the settlement zone between the two, the top fixed mounting of draft tube has the air guide, the heat-resisting pump of top fixedly connected with of air guide, the bottom fixedly connected with air guide cylinder of air guide, heat-resisting pump, air guide and air guide cylinder are located the center department of crystallizer and draft tube.

Preferably, the air guide device comprises connecting pipe, cavity drum and air duct, the top and the heat-resisting pump intercommunication of connecting pipe, the other end and the top intercommunication of cavity drum of connecting pipe, cavity drum and draft tube direct welded seal the air duct has four even and evenly distributed in the bottom of cavity drum and intercommunication, the one end of air duct and the upper surface connection of air duct.

Preferably, the air guide cylinder includes air guide cylinder outer wall, air guide cylinder inner wall and air guide hole, the top and the bottom of air guide cylinder outer wall and air guide cylinder inner wall are fixed connection respectively and form the cavity layer between the two, the air guide cylinder has been seted up on the air guide device heat-resisting pump is connected through the welded mode with the air guide device.

Preferably, the air guide holes are eight layers and six layers, the air guide cylinders are uniformly distributed at the middle lower part of the air guide device and communicated with the hollow layer, and the openings of the air guide cylinders are upward and thirty degrees are formed between the air guide cylinders and the air guide device.

The invention has the following beneficial effects:

1. compared with the prior art, the invention leads gas into the crystallizer through the inflatable stirring device, drives the feed liquid to rotate and rise, increases the circulation rate of the gas, can increase the stirring of the feed liquid, increases the flow rate of the feed liquid, increases the nucleation and crystal growth efficiency of solute, effectively reduces the mechanical collision of the crystal, reduces the damage of the crystal, improves the quality of the crystal, and simultaneously can reduce the contact point and time of the inner wall of the inflatable stirring device due to the gas flowing out of the inflatable stirring device, effectively reduces the formation rate of crystal scale on the inner wall of the inflatable stirring device, reduces the maintenance times of instruments and reduces the maintenance cost.

2. Promote and stir the feed liquid through letting in gas for the gas that lets in and feed liquid contact cool off the feed liquid, reduce the solubility of feed liquid, accelerate the feed liquid from supersaturated solution to reach saturated solution, accelerate crystal to separate out, improve crystal formation rate, break when the bubble reachs the liquid level simultaneously, improve liquid level solution rate of motion, accelerate evaporation cooling rate, increase crystal and separate out and growth rate.

Drawings

FIG. 1 is a schematic diagram of a prior art structure;

FIG. 2 is a schematic front view of the present invention;

FIG. 3 is a partial schematic view of the pneumatic stirring device of the present invention;

FIG. 4 is a schematic view taken from A-A in FIG. 2 according to the present invention;

FIG. 5 is a schematic view of the present invention at B-B in FIG. 2.

In the figure: 1. a crystallizer; 2. a draft tube; 3. a cylindrical baffle; 4. a stirring device; 5. a supersaturated feed liquid inlet; 6. a solution outlet; 7. a steam outlet; 8. elutriation column; 9. an air-filled stirring device; 91. a heat resistant inflator; 92. an air guide device; 93. an air guide cylinder; 931. the outer wall of the air guide cylinder; 932. the inner wall of the air guide cylinder; 933. and air vents.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 2-5, an air stripping DTB evaporative crystallizer includes a crystallizer 1, a draft tube 2, a supersaturated feed liquid inlet 5, a solution outlet 6, a steam outlet 7, and an elutriation column 8, wherein the draft tube 2 extends into the crystallizer 1, a settling zone is formed between the draft tube and the draft tube, an air guide 92 is fixedly installed at the top of the draft tube 2, a heat-resistant air pump 91 is fixedly connected to the top of the air guide 92, an air guide 93 is fixedly connected to the bottom of the air guide 92, and the heat-resistant air pump 91, the air guide 92, and the air guide 93 are located at the centers of the crystallizer 1 and the draft tube 2.

The gas guide device 92 is composed of a connecting pipe, a hollow cylinder and a gas guide pipe, the top end of the connecting pipe is communicated with the heat-resistant inflator pump 91, the other end of the connecting pipe is communicated with the top of the hollow cylinder, the hollow cylinder is directly welded and sealed with the guide cylinder 2, the guide cylinder 2 can be effectively sealed, effective control can be carried out on the pressure and the gas flow rate in the crystallizer 1, intelligent integrated production is achieved, four gas guide pipes are evenly distributed at the bottom of the hollow cylinder and communicated, one end of each gas guide pipe is connected with the upper surface of the gas guide cylinder 93, the heat-resistant inflator pump 91 fills gas into the hollow cylinder from the connecting pipe, and the gas guide pipes are conveyed into the gas guide cylinders 93 through the gas guide pipes, so that blocking of the gas guide pipes to liquid flowing is effectively reduced, a liquid.

The gas guide cylinder 93 comprises a gas guide cylinder outer wall 931, a gas guide cylinder inner wall 932 and a gas guide hole 933, the top and the bottom of the gas guide cylinder outer wall 931 and the top and the bottom of the gas guide cylinder inner wall 932 are fixedly connected respectively, a hollow layer is formed between the gas guide cylinder outer wall 931 and the gas guide cylinder inner wall 932, the gas guide cylinder 93 is arranged on the gas guide device 92, air enters the hollow layer and then is transmitted to the liquid material through the gas guide cylinder 93, the air is compressed by the gas guide cylinder 93 and then impacts the liquid material at a certain speed, the liquid material is lifted, breakage and damage caused by collision of crystals in the liquid material and machinery are reduced, the quality of the crystals is improved, the heat-resistant inflator 91 is connected with the gas.

The gas guide holes 933 are eight layers and six layers, the gas guide cylinders 93 are uniformly distributed at the middle lower part of the gas guide device 92 and are communicated with the hollow layer, the openings of the gas guide cylinders 93 are upward and thirty degrees are formed between the gas guide device 92, so that the liquid in the gas guide cylinders 93 can be effectively impacted and lifted upwards, the liquid can be rotated, the stirring effect on the liquid is improved, the cooling rate is increased, and the formation of crystals is accelerated.

According to the working principle, supersaturated feed liquid flows into the crystallizer 1 from a supersaturated feed liquid inlet 5, the feed liquid in the gas guide device 92 ring is pushed to rotate by gas entering from the gas-filled stirring device 9 and is pushed to rise to the liquid surface, the supersaturated feed liquid is evaporated and cooled on the liquid surface to reach a supersaturated state, part of solute is deposited on the surface of suspended particles to grow the crystals, a settling zone is formed between the crystallizer 1 and the guide cylinder 2, large particles settle in the settling zone, small particles are discharged from a solution outlet 6 along with mother liquid, enter a circulating pipe and are heated and dissolved, the crystals sink into the elutriation column 8 from the bottom of the crystallizer 1, the gas is in contact with the feed liquid and rapidly takes away heat in the feed liquid, and the gas is broken out from the liquid surface and then is discharged from a steam outlet 7 to form dynamic balance in the crystallizer 1.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides an air stripping formula DTB evaporative crystallizer, includes crystallizer (1), draft tube (2), supersaturated feed liquid import (5), solution outlet (6), steam outlet (7) and elutriation post (8), draft tube (2) stretch into the inside of crystallizer (1), and form the settling zone between the two, its characterized in that: the top fixed mounting of draft tube (2) has air guide device (92), the top fixedly connected with heat-resisting pump (91) of air guide device (92), the bottom fixedly connected with gas guide tube (93) of air guide device (92), heat-resisting pump (91), air guide device (92) and gas guide tube (93) are located the center department of crystallizer (1) and draft tube (2).

2. The air stripping DTB evaporative crystallizer of claim 1, wherein: the air guide device (92) comprises a connecting pipe, a hollow cylinder and an air guide pipe, the top end of the connecting pipe is communicated with a heat-resistant inflator pump (91), the other end of the connecting pipe is communicated with the top of the hollow cylinder, the hollow cylinder is directly welded and sealed with a guide cylinder (2), the air guide pipe is provided with four pieces of air which are uniformly distributed at the bottom of the hollow cylinder and communicated with the bottom of the hollow cylinder, and one end of the air guide pipe is connected with the upper surface of the air guide cylinder (93).

3. The air stripping DTB evaporative crystallizer of claim 1, wherein: air guide cylinder (93) include air guide cylinder outer wall (931), air guide cylinder inner wall (932) and air guide hole (933), the top and the bottom of air guide cylinder outer wall (931) and air guide cylinder inner wall (932) are fixed connection respectively and form the hollow layer between the two, air guide cylinder (93) have been seted up on air guide device (92) heat-resisting inflator pump (91) are connected through the welded mode with air guide device (92).

4. An air stripping DTB evaporative crystallizer as claimed in claim 3 wherein: the air guide holes (933) are eight layers and six layers, the air guide cylinders (93) are uniformly distributed at the middle lower part of the air guide device (92) and are communicated with the hollow layer, and the openings of the air guide cylinders (93) are upward and thirty degrees are formed between the air guide device (92).