Optimized process for producing super absorbent resin

Abstract

The invention relates to the technical field of preparation of super absorbent resin, and discloses an optimized process for producing super absorbent resin by a polymerization method, which comprises the following steps of: flattening gel by a flattening roller in a drying process of the production process, adjusting the flattened gel to a specified thickness, drying the flattened gel in a drying machine, crushing the dried material by a crushing shaft, and drying the crushed material by a drying machine; the drying and crushing efficiency is higher, the size and shape of obtained powder particles are more controllable, and the product quality and yield can be improved. Due to the fact that the ground and screened materials can form the water-absorbent resin with the excellent performance only through the post-treatment procedure, in the post-treatment procedure, the materials in the intermediate product bin pass through the rotary valve and are metered through the powder flowmeter, the purpose is to calculate the needed post-treatment additive amount through accurate metering, the production process is more accurate, and the production efficiency is improved. And the produced super absorbent resin has better performance. According to the optimized process, the product yield is higher, the product performance is more excellent, the production efficiency is higher, and the use amount of production materials is saved to the greatest extent.

Description

Technical Field

[0001] The present invention relates to the technical field of producing superabsorbent resins, and specifically to the process optimization of producing superabsorbent resins by a polymerization method. Background Art

[0002] Superabsorbent resin is a kind of polymer with a certain degree of crosslinking. Due to having a large number of hydrophilic groups and a network polymer structure, it can quickly absorb hundreds of times its own weight of water to form a gel, and this gel can still hold the water without separation under a certain pressure. These characteristics enable this new material to have a wide range of applications. It is used in paper diapers, sanitary napkins, and napkins in the papermaking process, bringing great convenience to people's daily lives. In the agricultural and gardening fields, superabsorbent resin can be used for soil water retention, and it can also be used as a water absorbent and a preservative for fruits and vegetables in the food industry. The excellent performance of superabsorbent resin has enabled it to be widely used. The polymerization method is a common method for producing superabsorbent resins. However, the existing process has the disadvantages of slow drying, difficult control of the particle size and shape of the resin particles after crushing, resulting in low production efficiency, difficult control of the crosslinking degree and quality of the final product, resulting in affected performance of the resin product, and difficult control of the additive dosage, resulting in waste of materials.

[0003] We optimized the process of preparing superabsorbent resin by the polymerization method, making the drying efficiency higher during the drying process, and the particle size of the resin after crushing more suitable and concentrated, with a more regular shape. In the post-treatment process, the dosage of the post-added treatment agent is determined by measuring the addition amount of the intermediate material, so that the crosslinking degree is well controlled, and the excessive use of additives is prevented, saving the material usage amount and making the production more precisely controllable. Summary of the Invention

[0004] The purpose of the present invention is to provide the process optimization of preparing superabsorbent resin by the polymerization method to solve the problems of slow drying, difficult control of the particle size and shape after drying and crushing, difficult control of the crosslinking degree and quality, resulting in poor product performance, etc. mentioned in the above background art.

[0005] To achieve the above purpose, the present invention provides the following process optimization:

[0006] Optimization 1: In the drying process, before the gel enters the dryer, it is first leveled and adjusted to a specified thickness. The purpose of this is to make the gel easier to dry, with higher drying efficiency, and the particle size distribution of the resin particles after drying and crushing more concentrated and meeting the particle size requirements, and the shape is easier to control, so the product quality is higher.

[0007] Optimization 2: In the post-treatment process, the amount of intermediate product material metered and added by a powder flowmeter is used to determine the amount of post-treatment additive to be added, thereby precisely controlling the crosslinking degree of the product, improving the product quality, and most precisely controlling the dosage of the additive to make the production more economical.

[0008] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0009] The gel after leveling and thickness adjustment dries faster in the dryer, resulting in an overall improvement in drying efficiency.

[0010] 2. When the gel dried after leveling and thickness adjustment is crushed, the particle size distribution of the powder is more concentrated and appropriate, and the shape is more regular. Therefore, the crushing efficiency of the product is higher, leading to a great improvement in the overall production efficiency.

[0011] 3. In the post-treatment process, before the intermediate product material is mixed with the post-treatment additive, the amount of intermediate product material metered and added by a powder flowmeter is used to determine the dosage of the post-treatment additive to be added, thereby more precisely controlling the crosslinking degree of the product resin, and accurately calculating the dosage of the post-treatment additive to be added, making the product quality higher and the production more economical. Specific embodiments

[0013] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0014] Example 1: The gel is distributed to the inlet of the Petri dryer through a gel distributor. The gel at the inlet is leveled and adjusted to a specified thickness by a leveling roller, then enters the Petri dryer for drying. The dried material is crushed by a crushing shaft, and the crushed material is conveyed by a screw conveyor to a coarse crusher for coarse crushing. The particle size after coarse crushing is <12 mm, and then it passes through a rotary valve and is sent to the coarse crushed product bin by a fan.

[0015] Example 2: The materials in the intermediate product bin pass through a rotary valve and are metered by a powder flow meter. They are added to the rotary valve tank, and at the same time, post-treatment additives are added according to the calculated specified addition amount. The mixed materials are transported to a Hof dryer through a screw conveyor. The Hof dryer controls the heating temperature through a hot oil system. The materials coming out of the Hof dryer are transported to a mixer through a screw conveyor. The materials are screened in a shaker screen. The large particles are cut off and put into a ton bag, and the fine powder at the top of the shaker screen is recovered into a bag filter. The materials with qualified particle sizes are transported to the finished product bin by a fan through a rotary valve.

[0016] It should be noted that:

[0017] (1) After a polymer with a spatial network structure absorbs water, it will form a gel. A large amount of liquid is contained inside the formed gel. When we dry the gel, we will obtain a resin, and both the shape and volume change, and the volume will decrease significantly.

[0018] (2) Under specific shapes and thicknesses, due to the relatively thin thickness and fixed shape, the gel dries more evenly, with higher efficiency, and when broken, the particle size distribution is more concentrated and the shape is more fixed.

[0019] (3) The powder flow meter is a flow detection device that uses electrostatic measurement technology. When an air flow containing dust particles in a pipeline passes through a fixed sensor, the weak current generated by the dust particles during movement is collected by the sensor and transmitted to the transmitter. After being filtered, amplified, and processed by the transmitter, it becomes a standard output value linearly related to the dust flow, so as to obtain the amount of powder flowing through. This powder flow meter has high sensitivity, is not affected by vibration, has high reliability, and a long service life.

[0020] The above shows and describes the basic principles, main features, and advantages of the present invention. Technical staff in this industry should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only preferred examples of the present invention and are not used to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

[0021] Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. It relates to the optimization of the process for preparing superabsorbent resins by polymerization, characterized in that, Before drying, level the gel and adjust its thickness first, and accurately measure the qualified powder material through a powder flowmeter to accurately confirm the specified addition amount of the post-treatment agent, so as to make the quality of the produced superabsorbent resin higher, the production efficiency higher, and the maximum utilization of materials realized.

2. According to the process optimization described in claim 1, in the drying process, before the gel enters the dryer, the gel first passes through a leveling roller to be leveled and adjusted to a specified thickness, and then dried, and then pulverized. By controlling the shape and thickness before drying, the drying efficiency is higher, the particle size and shape of the pulverized powder are easier to control, and the quality of the produced resin is higher.

3. According to the process optimization described in claim 1, since the dosage of the post-treatment additive will affect the product quality, a specified amount of the post-treatment additive must be used to achieve the best post-treatment effect. Therefore, we first measure the amount of the intermediate material with a powder flowmeter before the post-treatment process, and then add a fixed amount of the post-treatment additive according to the measurement result, so that the crosslinking degree of the product is appropriate, the quality is higher, the performance is better, and the usage amount of the post-treatment additive is saved, making the production more economical.