WO2009005411A2

WO2009005411A2 - Sorbent producing method and a device for carrying out said method

Info

Publication number: WO2009005411A2
Application number: PCT/RU2008/000521
Authority: WO
Inventors: Oleg Nikolaevich Krukovsky; Oleg Mikhailovich Flisyuk
Original assignee: Obschestvo S Ogranichennoi Otvetstvennostju 'areteech Solutions - Geoecologia'; Obschestvo S Ogranichennoi Otvetstvennostju 'intechproject'
Priority date: 2007-06-25
Filing date: 2008-08-15
Publication date: 2009-01-08
Also published as: WO2009005411A3; RU2343973C1

Abstract

The invention relates to methods for producing sorbents on mineral carriers which can be used for removing emulsified and dissolved petroleum products from water and for eliminating accidental petroleum product spills from water, ground and solid surfaces, and to a device for carrying out said method. The inventive sorbent producing method consists in supplying the particles of a carrier, in the form of an expanded perlite and/ or expanded vermiculite, and an organosilicon compound, in the form of an aqueous solution (oil-wetting agent), with compressed air for pulverising said organosilicon compound, to the drying area of a working chamber, in supplying a hot air stream to the working chamber to form, by said hot air stream, a spouted bed in the deposition and drying areas of the working chamber, in applying at least two layers of the organosilicon compound to the surface of the carrier particles by the interaction thereof with the organosilicon compound pulverised in the spouted bed in the deposition area and in drying the carrier particles provided with the applied organosilicon compound layer in the spouted bed of the working chamber drying area. A device for producing sorbents is also disclosed.

Description

METHOD FOR PRODUCING SORBENT AND DEVICE FOR ITS

IMPLEMENTATION

The invention relates to methods for producing sorbents based on mineral carriers and can be used to purify water from emulsified and dissolved oil products, as well as from accidental spills of oil products on water, soil and solid surfaces, as well as to a device for implementing this method.

Oil and products of its processing, falling into water, can be localized on its surface in the form of continuous films, disperse, forming emulsions such as "water in oil" and "oil in water", and partially dissolve. As a rule, water containing oil and oil products is purified by mechanical, physicochemical, chemical and biological methods, which, depending on the degree of water pollution, are included in the complex scheme of treatment facilities.

Among the most effective methods of purification of oily waters, ensuring the final content of oil products in water practically at the level of maximum permissible concentrations (MPC), adsorption on microporous sorbents plays an important role. Among the sorbents of this type, the most promising, in view of their availability and simplicity of manufacturing technology, are natural inorganic materials modified with organic compounds.

It is known that for the purification of waters contaminated with oil and oil products, expanded perlite is used, treated with a mixture of sodium polyorganosiliconate solutions in the following ratio, May: sodium methylsiliconate 40-60, sodium ethylsiliconate 10-40, sodium phenylsiliconate 5-30. The effectiveness of the adsorbent used is judged by

SUBSTITUTE SHEET (RULE 26) oil recovery capacity and water absorption in 24 hours, which are respectively 760-780 and 42-45 May. [USSR Copyright Certificate Ns 472109].

A hydrophobic adsorbent is known for collecting oil from the surface of water based on expanded perlite modified with sodium methylsiliconate and the sodium salt of adipic acid. The adsorbent is prepared as follows: 98.9 g of expanded perlite of the Aragat deposit with a bulk density of 100 kg / m ^{3 is} treated with 170 g of an aqueous solution containing 1.0 g of sodium methylsiliconate and 0.1 g of sodium adipate. The removal of solvent (water) is carried out by drying at 25O ⁰ C.

The oil absorption capacity and water absorption of the adsorbent are equal, respectively, to 920 and May 9. [Copyright certificate Ns 1193947].

The main disadvantages of the adsorbents made by the methods mentioned above are that they only retain floating and emulsified oil, and water-soluble oil products are not extracted from water.

A known method of producing a hydrophobic adsorbent for removing petroleum products from aqueous media, consisting in the fact that the expanded perlite is modified with polymethylhydridesiloxane with a volume ratio of W: T (0.3-0.6): 1 before applying 30-50% of the modifier by weight of perlite, and heat treatment is carried out at 320-380 ⁰ C for 0.3-0.5 hours

The perlite thus treated is thoroughly mixed and placed in a drying oven, where it is thermally oxidized in air at 320-380 ⁰ C for 0.3-0.5 hours, then the adsorbent is unloaded and cooled. The resulting modified perlite is ready for use.

SUBSTITUTE SHEET (RULE 26) The disadvantage of this method is the separation of the process at the stage of applying an aqueous solution of an organosilicon compound (water repellent) to the surface of the carrier particles and drying, which are carried out in different devices. For processing in two apparatuses, it is necessary to load and unload particles from the apparatuses twice, which leads to the destruction of carrier particles coated with a water repellent and the finished sorbent. This method allows to obtain on the surface of the carrier only a single layer film of an organosilicon compound (water repellent), which gives insufficient strength to the obtained sorbent particles. In addition, the use of high temperature in the drying process at 320-380 ⁰ C leads to high energy consumption.

Also known is a method of producing a sorbent for oil, oil products and liquid hydrocarbons, comprising applying an organosilicon compound (water repellent) to expanded perlite and / or vermiculite granules by means of mechanical stirring and drying, in which octyltriethoxysilane is used as an organosilicon compound, the application process which is carried out by mixing the granules of expanded perlite and / or vermiculite in a water-alcohol solution of octyltriethoxysilane to hydrolytic polycon ensatsii latter to form on the entire surface of the granule pores hydrolytically stable silicone film sorbent followed by drying in a stream of warm air or by natural means. (Patent for the invention of R.F. Ns 2255804, MPK: B01J20 / 32, publ. 10.07.05.) - prototype.

This method includes a large number of loading and unloading operations, which dramatically increases the processing time of the material and leads to its loss. Mechanical mixing of the carrier and the water repellent allows you to get on the surface of the carrier only a single layer film of an organosilicon compound (water repellent), which gives insufficient strength to the obtained particles of the sorbent.

SUBSTITUTE SHEET (RULE 26) This method does not allow for uniform drying of the sorbent particles from all sides, since the drying of the particles occurs when they are in a static state. This drying method can lead to clumping of particles of the obtained sorbent.

Thus, the disadvantage of this method is the high energy intensity, duration and technological complexity of the sorbent manufacturing process, the low degree of penetration of organosilicon compounds into the pores of the granules of the expanded medium.

The technical task of the present invention is the creation of such a method and device for its implementation, which would make it possible to obtain a multilayer film of a hydrophobizing agent on the surface of the carrier particles and ensure uniformity of drying of the obtained sorbent particles from all sides, which would make it possible to obtain a sorbent with high hydrophobic and sorption properties, and reduce energy consumption and the duration of the sorbent manufacturing process.

The problem is solved due to the fact that the proposed method for producing the sorbent includes feeding into the application zone in the working chamber particles of a carrier, which is used as expanded perlite and / or expanded vermiculite, and an organosilicon compound in the form of an aqueous solution (water repellent) together with compressed air providing spraying of said organosilicon compound, supplying a heated air stream to the working chamber to create a gushing layer in the working chambers by said heated air stream in zones of application and drying, applying to the surface of carrier particles of said silicon compound by reaction with an organosilicon compound in atomized spouted bed in a zone of application and drying of the carrier particles coated with a layer of the organosilicon compound spouted bed in the processing chamber in the drying zone.

SUBSTITUTE SHEET (RULE 26) According to the invention, in the working chamber in the application zone, at least two layers of water repellent are applied to the surface of the carrier.

In the working chamber in the application zone, the heated air stream has a temperature of 30-60 ⁰ C, and the residence time of the carrier with the silicon-organic compound in the flowing layer is 3-10 minutes, and in the drying zone the heated air stream has a temperature of 60-150 ⁰ C, and the drying time of the carrier particles is 3-10 minutes, while the velocity of the heated air in the application and drying zones is 0.2-0.8 m / s.

A device for producing a sorbent, contains a working chamber, consisting of a deposition zone and a drying zone, a hopper for loading into the working chamber in the zone of applying carrier particles, a first supply line for supplying an organosilicon compound in the form of an aqueous solution to the working chamber in the deposition zone, a second a supply line for supplying compressed air to the working chamber in the application zone, at least one nozzle connected to the specified first and second supply lines and spraying organosilicon connection in the working chamber in the application zone, the third supply line, designed to supply heated air to the working chamber, providing a flowing layer in the application and drying zones. The working chamber is made gutter-shaped and is located horizontally. In the bottom of the working chamber, you can make holes that will play the role of many air nozzles.

Due to the supply of heated air from 30 to 6O ⁰ C to the application zone in the working chamber and due to the presence of carrier particles with water repellent in the application zone for 3 to 10 minutes in the flowing layer, each carrier particle moves in an organized and cyclical manner and repeatedly enters the spray zone of the water repellent . The applied solution of the water repellent is absorbed into the pores of the carrier particles. This absorption process is accelerated.

SUBSTITUTE SHEET (RULE 26) b due to the temperature difference between the outer and inner layers of the particle (thermal diffusion), i.e. the degree of penetration of the organosilicon compound into the pores of the carrier granules increases, which leads to an increase in the hydrophobic and sorption properties of the obtained sorbent. At the same time, the water-repellent solution is dried on carrier particles at an average temperature in the flowing layer of 30-60 ⁰ C, i.e. a layer of water repellent is applied and then it is dried before applying the next layer and, thus, a multilayer coating is formed on the surface of the carrier particle. This method allows to obtain on the surface of each particle a more uniform and thicker coating of water repellent, protecting it from mechanical destruction, i.e. This method allows to increase the mechanical strength of the obtained sorbent particles.

Carrying out processes with certain parameters of temperatures and velocities of heated air, applying an aqueous solution of an organosilicon compound (water repellent) to the surface of the carrier particles and drying them in one continuous working chamber with a flowing layer created by a stream of heated air, reduces the loss of sorbent of substandard fraction by reducing the duration and technological complexity of the processes of applying an organosilicon compound to carrier particles and their drying and and exclusions of transhipment operations in the process. Since the drying process occurs with constant mixing of particles, clumping is eliminated and uniform drying of particles from all sides is ensured.

Due to the design of the working chamber in the form of a trough, carrier particles, which are used as perlite and / or vermiculite, 1-6 mm in size, which have a low density and a large surface, rise at high speed upward in the core of a heated fountain and then

SUBSTITUTE SHEET (RULE 26) scatter on the sides and slide down the inclined surface of the gutter down to the lower part of the fountain, and then are again picked up by the fountain jet.

The invention is illustrated by drawings, where: in FIG. 1 depicts a technological scheme for producing a sorbent; in FIG. 2 shows a diagram of a working chamber.

The technological scheme for producing the sorbent includes a working chamber 1, which consists of an application zone 2 and a drying zone 3, a hopper 4 for loading carrier particles into the working chamber 1 in the application zone 2, a supply line 5 to the application zone 2 of the organosilicon compound in the form of an aqueous solution, which includes a pump 6 for feeding a solution of an organosilicon compound (water repellent) from a container 7 to pneumatic nozzles 8, a supply line 9 to a zone 2 of applying a working chamber 1 of compressed air flow, which includes a compressor 10 for supplying compressed zduha to pneumatic nozzles 8, line 11 to feed the zones 2 and 3 of the processing chamber 1 of the heated air, which consists of a heater 12 and fan 13, discharge device 14 of the finished product from the processing chamber 1 in the hopper unloader 15 by a fan 16 pneumatic. The air from the working chamber 1 is dry cleaned in a direct-flow cyclone 17 and the exhaust fan 18 is released into the atmosphere. Bottom

19 of the working chamber 1 is made in the form of a gas distribution grill, with the help of which a gushing layer is created in the chamber 1. The working chamber 1 is made gutter-shaped. The separation into application zone 2 and drying zone 3 can be conditional, i.e. the first zone is due to the presence of nozzles 8 at the beginning of the chamber 1. Division into zones can also be done by installing a partition between the zones.

The method is as follows.

SUBSTITUTE SHEET (RULE 26) Particles of the carrier, which can be used as expanded perlite, expanded vermiculite or a mixture of expanded perlite and vermiculite with a particle size of 1-6 mm, are loaded into the hopper 4 of the feeder and fed through the device for loading particles of the carrier, made in the form of a screw, into zone 2 of application a working chamber 1 of continuous operation.

In zone 2 of the working chamber 1 through nozzles 8 from the hopper 7 using a pump

6, an aqueous solution of an organosilicon compound is supplied via line 5 (alkyl silicates, for example, sodium methyl silicate, sodium ethyl silicate, potassium methyl silicate, etc. can be used as an organosilicon compound (hydrophobizing agent) and compressed air through line 9 with a compressor 10. The supply of water-repellent and compressed air to the application zone 2 through nozzles 8 ensures that the water-repellent is sprayed in zone 2. Heated air is supplied to the working chamber 1 through line 11 through the openings in the bottom 19 of the working chamber 1, which creates a gushing layer consisting of carrier particles and water-repellent particles. In the gushing layer, the carrier particles rise up, then scatter on the sides and slide down the inclined surface of the chamber 1 into the lower part of the fountain and then rise up again, i.e. each particle repeatedly enters the spray zone of the water repellent. Since this process is carried out in a heated gushing layer, each layer of a hydrophobizing agent deposited on a carrier is dried due to its contact with a heated gas, which makes it possible to obtain a more uniform and thicker coating of a hydrophobizing agent on the surface of each carrier particle, which protects the particle from mechanical destruction, t. e. giving the particle strength.

The average temperature in zone 2 of the working chamber 1 is 30-60 ⁰ C and the residence time of the particles is 3-10 minutes.

Particles with a water-repellent deposited on their surface then fall into the drying zone 3 of the working chamber 1, in which the resulting sorbent particles are finally dried in a heated stream

SUBSTITUTE SHEET (RULE 26) flowing layer having an average temperature of 60-150 ⁰ C, and the residence time of particles in the drying zone is 3-10 minutes The speed of the heated gas in zones 2 and 3 of the working chamber 1 is 0.2-0.8 m / s. The finished product from the drying zone 3 through the discharge device 14 is discharged from the working chamber 1 into the hopper-unloader 15 by means of a fan 16 pneumatic conveying. The air from the working chamber 1 is dry cleaned in a direct-flow cyclone 17 and the exhaust fan 18 is released into the atmosphere.

The application of an aqueous solution of an organosilicon compound (water repellent) to the surface of the carrier particles and drying is carried out in one continuous working chamber 1. As a result, manual or mechanized transportation processes from one chamber to another are eliminated, and the possibility of mechanical destruction of particles is reduced. Particles rise at high speed upward in the core of the fountain, and then scatter along the sides and slide down the inclined surface of the gutter to the bottom of the fountain. This ensures a stable and organized mixing of particles in the layer, which eliminates the adhesion of particles, i.e. uniform drying of each particle occurs on all sides.

Particles of the carrier itself, which include expanded perlite, expanded vermiculite, or a mixture of expanded perlite and vermiculite, are very fragile and are easily destroyed during transportation, dosing and storage. The same thing happens with particles processed by known methods, i.e. with sorbent particles. Destruction of sorbent particles leads to the formation of a large amount of dust, which affects the environmental safety of working with sorbents and environmental pollution. Therefore, an increase in the mechanical strength of the particles of the finished sorbent is of fundamental importance.

SUBSTITUTE SHEET (RULE 26) Thus, with repeated coating of a particle with a hydrophobizing agent, a more uniform coating is formed, which gives the particles strength, the time for applying an aqueous solution of an organosilicon compound (hydrophobizing agent) to the carrier particles and their drying is reduced, and overload operations in the process are also excluded.

Example 1

As an organosilicon compound, sodium ethyl silicate (GKZh 11) is used, which is diluted with water so that the mass fraction of the basic substance is 4% and this solution is applied to perlite particles having a size of 3-5 mm in a continuous working chamber 1. The ingredients are taken in the proportion of 1 kg of solution per 1 kg of perlite, the average temperature in the flowing layer in zone 2 of applying the hydrophobizing solution to the carrier particles and drying the particles is 4O ⁰ C, the residence time of the particles in zone 2 was 5 minutes, and the heated gas velocity was 0.35 m / s. In zone 3 of the drying, the average temperature in the flowing layer was 8O ⁰ C, and the velocity of the heated gas was 0.35 m / s (sample 1).

Another sample of a sorbent based on perlite was obtained by applying a hydrophobizing solution, which was used sodium ethyl silicate (GKZh 11), with mechanical stirring at a temperature of 2O ⁰ C and subsequent drying in an oven at a temperature of 8O ⁰ C (sample 2). Then a 3-5 mm fraction was sieved and the obtained samples were compared by strength between each other and with the initial perlite carrier (sample 3) according to the standard method GOCT16188-70 “Copper, Methods for determining the abrasion strength” of determining the abrasion resistance. The samples were rotated in the drum for 3 minutes. at a speed of 85 rpm and then the fraction of the undisturbed initial fraction was determined. The results are shown in table 1.

SUBSTITUTE SHEET (RULE 26) 21

eleven

Tab. one

Example 2

As an organosilicon compound, sodium ethyl silicate (GKZh 11) is used, which is diluted with water so that the mass fraction of the basic substance is 3% and this solution is applied to vermiculite particles with a size of 2-6 mm in a continuous chamber 1 with a flowing layer , The working chamber 1 is made gutter-shaped and is located horizontally. The ingredients are taken in the proportion: 1 kg of solution per 1 kg of vermiculite, the average temperature in the flowing layer in the zone 2 of applying the solution and drying the particles is 4O ⁰ C, the residence time was 5 minutes, and the speed of the heated gas was 0.5 m / s.

In zone 3 of the drying, the average temperature in the flowing layer was 8O ⁰ C, and the velocity of the heated gas was 0.5 m / s (sample 1).

Another sample of sorbent based on vermiculite was obtained by applying a hydrophobizing agent solution, which was used sodium ethyl silicate (GKZh 11), with mechanical stirring at a temperature of 2O ⁰ C and subsequent drying in an oven at a temperature of 8O ⁰ C (sample 2). Then a 3-5 mm fraction was sieved and the obtained samples were compared in strength between each other and with the original vermiculite support (sample 3) according to the standard method GOCT16188-70 “Copper, Methods for determining the abrasion strength” for determining the abrasion resistance. In this case, the samples were rotated in the drum for 3 minutes. at a speed of 85 rpm and then the fraction of the undisturbed initial fraction was determined. The results are shown in table. 2.

SUBSTITUTE SHEET (RULE 26) 08 000521

12

Tab. 2

From tables 1 and 2 it is seen that the application of a water repellent on the surface of perlite and vermiculite particles leads to different degrees of hardening - samples 1 and 2.

According to the proposed method, when processing carrier particles in a heated gushing layer, including applying an aqueous solution of a hydrophobizing agent and partial drying in the application zone 2 in the working chamber 1, as well as subsequent drying in the drying zone 3 in the working chamber 1, a more uniform and a thicker coating consisting of at least two layers of a hydrophobizing agent protecting the obtained sorbent particles from mechanical destruction, i.e. This method allows to increase the mechanical strength of the obtained sorbent particles.

SUBSTITUTE SHEET (RULE 26)

Claims

CLAIM

1. A method of producing a sorbent, comprising the following steps: carrier particles are fed into a working chamber into a deposition zone, which include expanded perlite and / or expanded vermiculite, and an organosilicon compound in the form of an aqueous solution of water repellent together with compressed air, which atomizes the indicated organosilicon connections, a heated air stream is fed into the working chamber to create a specified flow of heated air of a gushing layer in the working chamber in the application and drying zones, on top of The particles of the carrier are applied to the indicated organosilicon compound by reacting these particles with the sprayed organosilicon compound in the gushing layer in the application zone, and the carrier particles with the deposited organosilicon layer are dried in the gushing layer in the drying zone.

2. The method of producing the sorbent according to claim 1, characterized in that in the working chamber in the application zone, the air flow has a temperature of 30-60 ⁰ C, and the residence time of the carrier with the organosilicon compound in the gushing layer is 3-10 minutes, and in the zone drying, the air flow has a temperature of 60-150 ⁰ C, and the drying time of the particles of the carrier is 3-10 minutes

3. The method of producing the sorbent according to claim 1, characterized in that the speed of the heated air in the application and drying zones is 0.2-0.8 m / s.

4. A device for producing a sorbent containing a working chamber consisting of a deposition zone and a drying zone, a hopper for loading carrier particles into the working chamber in the deposition zone, an unloading device for

SUBSTITUTE SHEET (RULE 26) unloading the finished product from the drying zone of the working chamber, the first supply line intended for supplying a silicon-organic compound in the form of an aqueous solution into the working chamber in the application zone, the second supply line intended for supplying compressed air to the working chamber in the application zone, at least one nozzle connected to the indicated first and second supply lines and providing atomization of the organosilicon compound in the working chamber in the application zone, a third supply line intended for feeding into the working chamber heated air flow, providing the creation of a gushing layer in the working chamber in the areas of application and drying.

5. A device for producing a sorbent according to claim 4, characterized in that the working chamber is made gutter-shaped and is located horizontally.

6. A device for producing a sorbent according to claim 4 or 5, characterized in that the bottom of the chamber is made in the form of a gas distribution grill.

SUBSTITUTE SHEET (RULE 26)