Soluble aluminum hydroxide seed crystal preparation system

Abstract

The utility model belongs to the technical field of aluminum hydroxide production process, and relates to a soluble aluminum hydroxide seed crystal preparation system which comprises a sand mill and a blending tank, and the sand mill is connected with the blending tank. The soluble aluminum hydroxide seed crystal preparation system provided by the utility model can overcome the defects of an original carbon separation method seed crystal preparation process, the prepared seed crystal has the characteristics of high activity, high stability and narrow particle size distribution, the acid solubility of soluble aluminum hydroxide is effectively improved, and the effect is good.

Description

TECHNICAL FIELD

[0001] The utility model relates to aluminium hydroxide production process technical field especially relates to a kind of easily soluble aluminium hydroxide seed preparation system. BACKGROUND

[0002] Easily soluble aluminium hydroxide molecular formula is Al2O3.3H2O or Al(OH)3, molecular weight is 78, is new product specially developed according to polyaluminium chloride production process demand for the reaction residual quantity big, energy consumption high, process complex disadvantage of ordinary aluminium hydroxide production polyaluminium chloride, with superior solubility.

[0003] Polyaluminium chloride is an inorganic polymer coagulant, is the inorganic polymer water treatment agent of large molecular weight, higher charge due to the bridging effect of hydroxyl ion and the polymerization of polyvalent anion.Polyaluminium chloride is a water purifying agent, can remove bacteria, remove odor, decolorization etc., also can be used for the treatment of special water quality such as purifying drinking water and tap water supply, such as removing iron, removing cadmium, removing fluorine, removing radioactive pollutants, removing oil slick etc.

[0004] Ordinary aluminium hydroxide production polyaluminium chloride has the disadvantages of large reaction residual quantity, high energy consumption and complex process.Easily soluble aluminium hydroxide, its crystal structure is loose and irregular, acid leaching rate is high, residual is little, reaction speed is fast, efficiency is high, energy consumption is low at normal temperature, production process is pollution-free and dust-free, is high-performance green energy-saving raw material for producing polyaluminium chloride.Easily soluble aluminium hydroxide is obtained by adding active seed crystal to bayer liquor, controlling reasonable decomposition temperature and small temperature gradient, and not circulating seed.Easily soluble aluminium hydroxide is widely used in various aluminum salt, catalyst, filler and other industries due to its superior solubility, especially in water purifying agent industry, has incomparable advantage compared with ordinary aluminium hydroxide.Under the same conditions, raw material consumption is low, reaction speed is fast, equipment service life is long, production cost is low, and it is expected to replace ordinary aluminium hydroxide to become the main raw material for producing water purifying agent in the future.With the vigorous development of domestic water purifying agent industry, the industry competition is fierce, and the quality requirement is higher and higher.

[0005] The early preparation of the easily soluble aluminum hydroxide seed crystal adopts the sodium aluminate carbonation decomposition method. The method is a method for preparing the seed crystal by introducing carbon dioxide gas into a sodium aluminate solution. It is a complex multiphase reaction of three phases of gas, liquid and solid, including the absorption of carbon dioxide by the sodium aluminate solution and the chemical reaction therebetween and the crystallization of the aluminum hydroxide. In the early stage of the carbonation decomposition, the caustic alkali in the solution is continuously neutralized, but the aluminum hydroxide does not correspondingly precipitate with the decrease of the caustic coefficient of the solution. There is an induction period from the neutralization of the caustic alkali by the introduction of the carbon dioxide to the precipitation of the aluminum hydroxide. Without the seed crystal, due to the large interfacial tension between the sodium aluminate solution and the aluminum hydroxide, the new phase of the aluminum hydroxide generated during the decomposition becomes the crystal nucleus, the surface area thereof is extremely large, the decomposition process cannot provide such a large surface energy, the crystal nucleus is difficult to be spontaneously generated, and there is an induction period. However, with the continuous introduction of the carbon dioxide, when the caustic ratio decreases to a certain degree, the solution is in an extremely unstable state. The aluminum hydroxide is precipitated from the solution, and an autocatalytic process is formed. The carbonation decomposition adopts the lime furnace gas (containing about 38%-40% of CO2), the decomposition speed is fast, the content of the fine particles in the aluminum hydroxide is large, the average particle size of the carbonation product aluminum hydroxide is increased by prolonging the gas introduction time. The decomposition temperature is also a main factor affecting the particle size of the aluminum hydroxide. The increase of the temperature greatly increases the crystal growth speed. The decrease of the temperature can increase the saturation. Too low temperature can increase the secondary nucleation and make the product refined. The higher the temperature, the larger the particle size of the decomposition product. The preparation of the easily soluble aluminum hydroxide seed crystal by the carbonation decomposition method is affected by the carbonation decomposition process characteristics, temperature fluctuation, secondary nucleation and other factors in the actual production process. The seed crystal prepared by the carbonation decomposition method has a wide particle size distribution, a large specific surface area index fluctuation and unstable seed crystal activity. It is an important factor restricting the improvement of the acid solubility of the easily soluble aluminum hydroxide. Practical new type content

[0006] Therefore, the utility model provides a kind of easily soluble aluminum hydroxide seed crystal preparation system.

[0007] Specifically, the utility model is realized by the following technical scheme:

[0008] According to the first aspect of the utility model, an easily soluble aluminum hydroxide seed crystal preparation system is provided, comprising: a sand mill and a blending tank, wherein the sand mill is connected with the blending tank.

[0009] Optionally, it further comprises a buffer tank, and the buffer tank is connected with the sand mill.

[0010] Optionally, it further comprises a first conveying pump, and the first conveying pump is connected with the buffer tank and the blending tank respectively.

[0011] Optionally, it further comprises a second conveying pump, and the second conveying pump is connected with the buffer tank and the sand mill respectively.

[0012] Optionally, further comprising: a third delivery pump connected with the sand mill.

[0013] Optionally, further comprising: a dedicated hydrogen compressor underflow tank connected with the third delivery pump.

[0014] Optionally, further comprising: a fourth delivery pump connected with the dedicated hydrogen compressor underflow tank.

[0015] Optionally, further comprising: a carbon separation tank connected with the fourth delivery pump.

[0016] The technical scheme provided by the utility model has at least the following beneficial effects:

[0017] The easy-dissolving aluminum hydroxide seed crystal preparation system provided by the application can overcome the drawbacks of the original carbon separation method for preparing seed crystals, the prepared seed crystals have the characteristics of high activity, high stability and narrow particle size distribution, the acid solubility of the easy-dissolving aluminum hydroxide is effectively improved, and the effect is good. BRIEF DESCRIPTION OF DRAWINGS

[0018] The accompanying drawings, which are incorporated into and form part of the specification, illustrate embodiments consistent with the utility model and, together with the specification, serve to explain the principles of the utility model.

[0019] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, the accompanying drawings needed to be used in the embodiments or related technical description will be briefly introduced below, and obviously, other accompanying drawings can also be obtained by those skilled in the art without creative labor.

[0020] Figure 1 A structure schematic view of an easy-dissolving aluminum hydroxide seed crystal preparation system provided by the utility model embodiment. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical scheme and advantages of the utility model embodiments clearer, the technical scheme in the utility model embodiments will be clearly and completely described below in combination with the accompanying drawings in the utility model embodiments, obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.

[0022] Figure 1 A easy-dissolving aluminum hydroxide seed crystal preparation system suitable for the utility model embodiments is schematically shown.

[0023] REFERENCE Figure 1As shown, the application provides a preparation system of soluble aluminum hydroxide seed crystal, comprising: a sand mill and a mixing tank, wherein the sand mill is connected with the mixing tank.

[0024] In the embodiment of the application, the sand mill is used to prepare soluble aluminum hydroxide seed crystal from raw materials, and the soluble aluminum hydroxide seed crystal is gathered in the mixing tank.

[0025] Exemplarily, it further comprises a buffer tank connected with the sand mill.

[0026] In the embodiment of the application, the buffer tank is used to receive unqualified soluble aluminum hydroxide seed crystal, such as soluble aluminum hydroxide seed crystal with oversized size, discharged from the sand mill.

[0027] Exemplarily, it further comprises a first conveying pump connected with the buffer tank and the mixing tank respectively.

[0028] In the embodiment of the application, part of the unqualified soluble aluminum hydroxide seed crystal will enter the mixing tank, and at this time, the first conveying pump is needed to suck and convey it to the buffer tank.

[0029] Exemplarily, it further comprises a second conveying pump connected with the buffer tank and the sand mill respectively.

[0030] In the embodiment of the application, the second conveying pump sucks the unqualified soluble aluminum hydroxide seed crystal stored in the buffer tank and conveys it to the sand mill for reprocessing, so as to obtain qualified soluble aluminum hydroxide seed crystal.

[0031] Exemplarily, it further comprises a third conveying pump connected with the sand mill.

[0032] In the embodiment of the application, the third conveying pump is used to convey processing required substances, such as raw materials, to the sand mill.

[0033] Exemplarily, it further comprises a special hydrogen compressor underflow tank connected with the third conveying pump.

[0034] In the embodiment of the application, the special hydrogen compressor underflow tank is used to store processing raw materials, and the processing raw materials are conveyed to the sand mill via the third conveying pump.

[0035] Exemplarily, it further comprises a fourth conveying pump connected with the special hydrogen compressor underflow tank.

[0036] In the embodiment of the application, the fourth conveying pump is used to convey processing required substances, such as processing auxiliary materials, to the special hydrogen compressor underflow tank.

[0037] Exemplarily, the carbon separation tank is connected with the fourth conveying pump.

[0038] In the embodiment of the present application, the carbon separation tank is used for storing the processing auxiliary material, and the processing auxiliary material is conveyed to the bottom tank of the hydrogen compressor by the fourth conveying pump.

[0039] In the embodiment of the present application, the sand mill is used to grind the seed crystal, which can grind the seed crystal with finer, uniform, concentrated particle size distribution and higher activity. The sand mill has the most narrow grinding cavity, the smallest gap between the stirring rods and the most concentrated grinding energy. In combination with the internal high-performance cooling system and the automatic control system, the material can be continuously processed and discharged, greatly improving the production efficiency. The sand mill belongs to a wet ultra-fine grinding equipment and is developed from a ball mill. The slurry in the cylinder is ground to qualified slurry, which flows out through a filter gap or sieve hole smaller than the grinding medium particle size. The cylinder part is provided with a cooling or heating device to prevent the product quality from being affected by the heat generated by the mutual friction of the material, grinding medium and disc, or the grinding efficiency from being affected by the reduced flowability due to the condensation of the slurry. The sand mill has the effects of dispersion and mixing while refining the material. When the sand mill is applied to wet grinding of aluminum hydroxide, the closed continuous production has the advantages of uniform grinding and dispersion fineness, good quality and high production efficiency.

[0040] The seed crystal preparation system for easily soluble aluminum hydroxide provided in the present application can overcome the drawbacks of the original carbon separation method for preparing seed crystal, the prepared seed crystal has the characteristics of high activity, high stability and narrow particle size distribution, effectively improves the acid solubility of easily soluble aluminum hydroxide, and has good effect.

[0041] It should be noted that in the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "vertical", "horizontal", "transverse", "longitudinal" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0042] In addition, in addition to indicating the orientation or positional relationship, the above-mentioned terms can also be used to indicate other meanings, for example, the term "upper" can also be used to indicate a certain attachment relationship or connection relationship in some cases. For those skilled in the art, the specific meaning of these terms in the present application can be understood according to the specific situation.

[0043] In addition, the terms "mount", "set", "provided with", "connected", "linked" should be interpreted broadly. For example, it can be fixed connection, detachable connection, or integral structure; can be mechanical connection, or electrical connection; can be directly connected, or indirectly connected through an intermediate medium, or internal communication between two devices, elements or components. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0044] In addition, the terms "first", "second" and the like are mainly used to distinguish different devices, elements or components (the specific type and structure can be the same or different), and are not intended to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise stated, the meaning of "a plurality of" is two or more.

[0045] The above is only a specific embodiment of the present application, so that those skilled in the art can understand or implement the present application. Various modifications of these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features applied herein.

Claims

1. A system for preparing soluble aluminum hydroxide seed crystals, characterized in that: include: A sand mill and a mixing tank, wherein the sand mill is connected to the mixing tank; The system further comprises: a buffer tank connected to the sand mill; The system further includes: a first delivery pump, the first delivery pump being connected to the buffer tank and the mixing tank respectively; The system further comprises: a second delivery pump, the second delivery pump being connected to the buffer tank and the sand mill respectively; The system further comprises: a third delivery pump connected to the sand mill; The system further comprises: a dedicated hydrogen compressor underflow trough, the dedicated hydrogen compressor underflow trough being connected to the third delivery pump; The system further comprises: a fourth delivery pump connected to the bottom flow tank of the dedicated hydrogen compressor; The system further includes a carbon separation tank connected to the fourth delivery pump.

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