diálogos ELE

The GEA turbulence with draft tube and baffle crystallizer is the typical modern type of crystallizer in the industry. This is a typical model of mixing tank crystallizer. Draft tube is mounted inside, allowing crystals which are growing to be sent efficiently to the evaporation. In a continuous crystallization process employing an evaporative draft tube baffle (DTB) crystallizer apparatus to produce crystal product, the improvement which.

Author: Gorisar Voodoorn
Country: Syria
Language: English (Spanish)
Genre: Spiritual
Published (Last): 15 March 2016
Pages: 193
PDF File Size: 14.43 Mb
ePub File Size: 15.5 Mb
ISBN: 266-8-86163-553-3
Downloads: 58788
Price: Free* [*Free Regsitration Required]
Uploader: Aratilar

These fines are separated from the crsytallizer suspension of crystals by gravitational settling in the annular baffle zone. Forced-circulation crystallization is the most widely used crystallization method in industry.

Draft Tube Baffle (DTB) Crystallizer – Swenson Technology

The key assumption of an MSMPR crystallizer is that the slurry is perfectly mixed and uniform throughout the system. The batch vacuum crystallizer is particularly useful when processing materials that tend to grow on the walls of continuous crystallization equipment.

This is particularly true for materials which are used in the fertilizer applications, such as ammonium sulfate, potassium chloride, and potassium sulfate. Crystal slurry is removed via line 17 by the suction of pump 18 and ‘ drwft to a thickener 19 by line 17a. The baffle permits separation of unwanted fine crystals from the suspension of growing crystals, thereby affecting control of the product size.

A process for the preparation of a coarse-grained ammonium sulfate product by crystallization and plant for carrying out the method. Lapsed in a contracting state announced via postgrant inform.

It was found that the crystals in the suspension must be a mixture of medium sized crystals cdystallizer to 10 mesh and smaller sized below 14 Tyler mesh. Crystallizers such as these are the most useful for operations in which the solution’s boiling point is extremely high, or when such low temperatures are crystallizeg that evaporation by vacuum is not possible. Get a quote Contact Us. The DTB crystallizer is used when a larger particle size is desired.


Method and apparatus for the continuous production of a coarse-grained crystalline ammonium sulfate product. Granular size crystals, i. Flotation cell Furnace High Pressure Roller. The internal circulator provides the mixing of the slurry at a very low energy input, which is improves the growth rate of the crystals, and has low attrition for drafh crystals formed.

Draft Tube Baffle Type | Chem Process Systems

Method and device for producing a coarse-grained ammonium sulfate product crystallisate. ES Free format text: This supersaturation is relieved either by deposition of newly-formed ammonium sulfate on existing crystals which is desirable or by formation of new fine ammonium sulfate crystals often referred to as nuclei, which is undesirable because it leads to smaller-sized crystals.

When destruction of fines is not needed or wanted, baffles are not provided and the internal circulation rate is set to have the minimum nucleating influence on the suspension. DTB crystallizers in the chemical industry. Elutriation, like baffling, removes smaller particles from the slurry, except elutriation separates particles based on weight rather than size.

DE Date of ref document: Its distinct zones of growth and clarified mother liquor make it possible to define in terms of kinetic parameters, and thus growth and nucleation rates can be determined. The process of claim 6 wherein the suspension of crystals is fed in step g to the body of slurry at a point at or adjacent to the liquid level in the DTB crystallizer vessel. The percent of crystals of size greater than Tyler 10 mesh are given in Figure 2 for several successive shifts of production.

The thickened crystal slurry is discharged to a centrifuge 20 where crystals are separated from mother liquor.

This is achieved by a separation of the crystals from the liquid mass, in order to manage the two flows in a different way. The process of any of preceding claims comprising the continuous crystallization of ammonium sulfate.

Process for recovering terephthalic acid from pulverized product of spent polyethylene terephthalate and crystallizef for use in such process.


DTB Crystallizer

Vaporization occurs at the top surface of the slurry, while crystllizer occurs near the bottom of the crystallizer body. Process for the crystallization of solid substances in a coarse granular form from solutions.

The solute of this supersaturated solution then cools, forming crystals. The two DTB crystallizers shown below are used to produce ammonium sulfate. Frequent flushings required to minimize deposits on the crystallizer wall Cannot effectively handle a high density slurry.

Draft tube baffle crystallizers are used to control crystal size and characteristics. Country of ref document: This type of crystallizer is used primarily in the production of a variety of large-size crystalline materials such as ammonium sulfate, potassium chloride and diammonium phosphate for the fertilizer industry.

Elutriation is the process of flowing air over particles. When large evaporation rates are required, external heating must be provided.

It has an internal circulator which pushes the solution upwards in a draft tube while outside the crystallizer there is a settling area in an annulus; in it the exhaust solution bafflee upwards at a very low velocity. The forced-circulation crystallizer shown on the left is used to abffle sodium sulfate, while that on the right is used in the agricultural industry.

Main Office Swenson Technology, Inc. These wide variations in crystal size distribution are undesirable because there is loss of premium priced large crystals, introduction of non-uniformity in product size caused by segregation in storage piles and difficulties baflfe screening.

When the crystallizer produces a preponderance of large crystals, removal of mother liquor is expedited and the drying and screening operations are more efficient. To achieve an effective process control it is important to control the retention time and the crystal mass, to obtain the optimum conditions in terms of crystal specific surface and the fastest possible growth.