CN112536144A

CN112536144A - Method for improving titanium dioxide dispersibility and crushing and feeding device thereof

Info

Publication number: CN112536144A
Application number: CN202011497386.3A
Authority: CN
Inventors: 唐臣成; 卢慧军; 王国锋; 鞠浩; 范双
Original assignee: Xiangyang Lomon Titanium Industry Co Ltd
Current assignee: Xiangyang Lomon Titanium Industry Co Ltd
Priority date: 2020-12-17
Filing date: 2020-12-17
Publication date: 2021-03-23

Abstract

The invention discloses a method for improving titanium dioxide dispersibility and a crushing and feeding device thereof, belonging to the technical field of titanium dioxide calcination production. On the basis of the prior art, although the change is small, the qualification rate of high stirring dispersity is about 95 percent, and is improved by 25 percent compared with 70 percent of the prior art; the yield of high-stirring dispersion is greatly improved by adopting the magnetic drive gear pump to convey the active agent, the guarantee premise is provided for the product quality of enterprises, the relative economic benefit is further improved, and compared with the same sulfuric acid method titanium dioxide manufacturers, the stability of the quality can bring great advantages to the companies and increase the competitiveness of the companies aiming at improving the yield of high-stirring dispersion.

Description

Method for improving titanium dioxide dispersibility and crushing and feeding device thereof

Technical Field

The invention belongs to the technical field of titanium dioxide calcination production, and particularly relates to a method for improving titanium dioxide dispersibility and a crushing and feeding device thereof.

Background

At present, the titanium dioxide industry develops faster, mainly sulfuric acid process titanium dioxide and chlorination process titanium dioxide, wherein the sulfuric acid process titanium dioxide is more mature than the developing chlorination process technology. SulfurTiO calcined in acid process₂Most are agglomerates of pigment particles, which are difficult to meet the requirements of current industrial applications, and require grinding, pulverization, etc. before product packaging (non-pigment grade). With the development of some manufacturing industries, particularly the demand of the paint industry for titanium dioxide is larger and larger, correspondingly, the quality requirement for the titanium dioxide is stricter and stricter, and titanium dioxide products with different properties are required according to different product characteristics. The pigment performance of titanium dioxide is a concrete embodiment of its optical properties, which depend on its particle size and particle size distribution. When the particle size of the titanium dioxide is 0.2-0.4 μm, the light scattering power is highest and the color is whitest.

In the production process of titanium dioxide, firstly, the acidolysis process requires proper fineness of mineral powder to control the reaction process; on the other hand, the fineness of the falling product is controlled to be appropriate. Therefore, the correct selection and reasonable utilization of crushing and grinding equipment are the crucial links in the titanium white production.

The metatitanic acid is calcined to obtain a kiln product which is an aggregate and a sinter with different sizes, and the kiln product is crushed to the original basic pigment particle size (0.2-0.3 mu m) to fully embody the optical property and the pigment performance of the metatitanic acid. The basic pigment particles are primary particles produced by a titanium liquid hydrolysis process, gradually grow into basic pigment particles during calcination, and are then sintered and aggregated at a high temperature, and the crushing process is only to break the aggregates of the primary particles, which cannot be obtained by mechanically crushing the primary pigment particles.

At present, the primary finished product crushing method of titanium dioxide in the industry can be divided into dry grinding and wet grinding. The main process flow of the dry grinding system is that TiO2 particles are sent into a grinder by feeding equipment to be ground and then sent to a classifier to be sorted by adopting a pneumatic conveying mode, and qualified TiO2 powder particle products are collected into a storage bin to be stored by a bag type dust collector; mixing the primary treated TiO2 powder particles and desalted water in proportion into slurry with a certain concentration, and using the slurry for a sand mill. Returning the unqualified TiO2 material to the mill for continuous grinding, discharging part of dust gas in the system after reaching the limit value regulated by the national discharge standard, and returning the rest gas to the mill system. Wet grinding is a grinding process newly developed by a titanium dioxide manufacturer abroad on the basis of production practice in recent years. The production process includes feeding titanium white powder particle from the feeding system, rolling and grinding into sheet, mixing with desalted water and dispersant in certain proportion inside a tangent mixer, re-grinding and mixing in a disperser to obtain slurry meeting the requirement of sand mill in certain reflux ratio.

In the existing production of titanium dioxide by a sulfuric acid method, crushing is the last step of a finished product, a liquid active agent is added in the crushing process, and the finished product of titanium dioxide can be obtained after the crushing is finished. Whether the titanium dioxide is qualified or not is measured, whether the titanium dioxide has high stir dispersibility or not is mainly considered, the particle size is usually required to be not higher than 40 micrometers, obvious particles cannot be seen by naked eyes when the titanium dioxide is stirred in water, namely, the titanium dioxide has good dispersion and high stir dispersibility, but in the existing production, the addition of an active agent or a dispersing agent is intermittent, the qualification rate of the obtained titanium dioxide with high stir dispersibility is only 70%, the requirements of customers cannot be met, and the titanium ore resource is wasted.

Disclosure of Invention

In the existing crushing production process of titanium dioxide falling products, a plunger pump is used for adding an active agent in long-time production, and the plunger pump is not easy to block due to large aperture. But the produced titanium dioxide is difficult to reach the standard on the particle size of powder, and the dispersibility and whiteness of the product are relatively poor.

The invention aims to provide a method for improving titanium dioxide dispersibility and a crushing and feeding device thereof, and aims to solve the technical problems of low percent of pass in the existing titanium dioxide production.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a method for improving the dispersity of titanium white powder is characterized by adding an active agent continuously and uniformly in the step of crushing the titanium white powder in a kiln.

Preferably, the active agent is added by means of a gear pump in a continuous, uniform manner.

A falling kiln product crushing system device for improving the dispersibility of titanium dioxide uses a gear pump as a dispersing agent or an adding device of an active agent in a traditional wet-method rolling and grinding system.

Compared with the prior art, the invention has the following beneficial effects:

1. on the basis of the prior art, the gear pump is adopted to replace the traditional plunger pump, the qualification rate of high stirring dispersity is about 95 percent, the qualification rate is improved by 25 percent compared with 70 percent in the prior art, the particle size is more uniform, the quality is higher, and the economic effect is obviously improved;

2. the invention has small modification on the basis of the existing process line, can be realized by changing the original plunger pump into a gear pump, has low modification cost, greatly improves the production efficiency, reduces the production cost and saves mineral resources;

3. the use amount of the active agent can be reduced in a mode of continuously adding the active agent at a constant speed under the same product quality requirement;

4. the invention uses the gear pump to convey the active agent, is relatively stable in the process of conveying liquid, has no pulsation in conveying, extremely small pump vibration, extremely low noise and high temperature resistance, ensures that the active agent can be stably and uniformly added, has small abrasion and longer service life;

5. the yield of high-stirring dispersion is greatly improved by adopting the magnetic drive gear pump to convey the active agent, the guarantee premise is provided for the product quality of enterprises, the economic benefit is relatively improved, and compared with the same sulfuric acid method titanium dioxide manufacturers, the stability of the quality can bring great advantages to the companies and increase the competitiveness of the companies aiming at improving the yield of high-stirring dispersion.

Detailed Description

The present invention is further illustrated by the following examples, which include, but are not limited to, the following examples.

The embodiment prepares two existing crushing devices with basically equivalent operating conditions, wherein one device is modified by equipment, and the specific modification is as follows: on the basis of the existing crushing device, the plunger pump for feeding is changed into a type: and OMP and Q are gear pumps of 80-1000 ml/min.

Under the same crushing time, respectively adopting two improved devices and two unmodified devices to carry out crushing operation, and respectively producing 10 batches of titanium dioxide, wherein the high stirring dispersity of each batch of titanium dioxide is as follows:

as shown in the table, the improved equipment produces powder with higher concentration of powder grain diameter and more stable quality compared with the equipment before improvement.

The parameters of the gear pump and the plunger pump in the conveying process are compared, the gear pump is continuous and stable in the conveying process and can ensure the uniform and stable addition of the active agent, the plunger pump is discontinuously added, the addition amount is not stable enough, the stable and uniform addition of the active agent is difficult to control, and the unstable addition of the active agent can cause disqualification of high-stirring dispersion; the gear pump can be just used for stably adding the active agent, so that the qualification rate of high stirring dispersion is ensured, and the qualification rate of the high stirring dispersion after equipment improvement is about 95 percent, which is improved by 25 percent compared with the prior plunger pump by 70 percent.

The above-mentioned embodiment is only one of the preferred embodiments of the present invention, and should not be used to limit the scope of the present invention, but all the insubstantial modifications or changes made within the spirit and scope of the main design of the present invention, which still solve the technical problems consistent with the present invention, should be included in the scope of the present invention.

Claims

1. A method for improving the dispersibility of titanium dioxide is characterized in that in the step of crushing titanium dioxide falling products, an active agent is added continuously at a constant speed.

2. The method for improving the dispersibility of titanium dioxide according to claim 1, wherein the active agent is added by means of a gear pump.

3. A kiln falling product crushing and feeding device for improving titanium dioxide dispersibility is characterized in that a gear pump is used as a dispersing agent or an active agent feeding device in a traditional wet-method rolling and grinding system.