Recuperating ethylene and vinylacetate from stream of residual gas formed during synthesis of copolymer of vinyl ester and ethylene

FIELD: chemistry.

SUBSTANCE: invention relates to a method of recuperating unreacted monomers contained in a stream of residual gas formed during synthesis of a copolymer of vinyl ester and ethylene. Described is a method of producing copolymers containing vinyl ester or ethylene or ethylene unsaturated monomers via radical emulsion or suspension polymerisation in an aqueous medium at absolute pressure between 5 and 100 bars. At the end of polymerisation, the reaction mixture is throttled with reduction of its absolute pressure to 0.1-5 bars. Unreacted monomers are recuperated from the residual gas through multi-step fractionated condensation with deep cooling. At the first condensation step, water vapour is condensed at temperature ranging from -90 to -60°C, and at the third condensation step, ethylene is condensed at temperature ranging from 140 to 100 °C.

EFFECT: design of a method which enables extraction of valuable substances from the formed residual gas, where the said substances can be cheaply recycled.

9 cl, 2 dwg, 1 tbl, 1 ex

 

The present invention relates to a method of recovery of unreacted monomers contained in the residual gas stream generated in the process of obtaining a copolymer of vinyl ester and ethylene.

Polymers based on vinyl ester and ethylene is often used in the form of aqueous dispersions or holder in water powders in a variety of areas, for example, as materials for coating on a variety of bases or as adhesives for various foundations.

A characteristic feature of the polymerization processes carried out in industrial scale, is the high degree of transformation of the initial reagents. Usually in the processes of polymerization, the amount of residual monomers does not exceed 0.1 wt.%, mostly even not greater than 0.05 wt.%, and in the polymerization of vinyl chloride is not more than 0.01 wt.%. However, such a high degree of transformation is characteristic only of monomers, which in the conditions of polymerization are in the liquid state. Ethylene, the polymerization is a gaseous monomer, is not subject to such laws. First, the ethylene polymerizes more slowly than, for example, vinyl acetate, and secondly, a significant amount remains in the gas phase and therefore unable to react in the usual what's the conditions of emulsion polymerization.

To improve the economic efficiency of the polymerization process on an industrial scale its duration should be reduced to the lowest possible, which, however, inevitably leads to the impossibility of depletion only used ethylene. Typically, the polymerization is terminated by the ethylene content in the tail gas is less than 5 wt.%, mostly less than 2 wt.%, and the reaction mixture drossellied. The throttling process is to bypass the reaction mixture consisting of a polymer dispersion and residual gas from the pressure reactor under normal pressure reactor, the so-called expander, with the office of the residual ethylene. The resulting residual gas contains mainly ethylene, vinyl acetate, nitrogen and water vapor.

The resulting residual gas is commonly used as an energy source and disposed of by burning. However, due to the constant rise in the cost of raw materials economically much more feasible recovery of the individual components of the residual gas, including the contained unreacted monomers.

In the prior art there are known various methods of recovery of residual ethylene. For example, in WO 01/00559 A1 describes a method for the recovery of ethylene from a stream containing enertrag the gas, formed upon receipt of vinyl acetate. For this atlantagay inert gas is dissolved in the vinyl acetate by throttling the vacuum tank release ethylene gas and then re-compress it for reuse. In this publication also describes a method comprising dissolving thread atlantabased inert gas in acetic acid, in contact with which is then injected atlantagay residual gas in the Stripping column, from the top of which select the recovered ethylene, which is then again used in the synthesis of vinyl acetate.

In EP 0127253 A1 describes a method of removing residual monomers for obtaining copolymers of ethylene with higher olefins gas-phase polymerization. To do this, the solid copolymer under reduced pressure to remove the higher olefins, and then it is treated exhaust from the reactor gas, which does not contain an inert gas and which in the end return to the polymerization process.

In EP 1420034 A1 describes a method of producing a copolymer of vinyl ester and ethylene by radical polymerization, formed when atlantagay residual gas after compression is again dissolved in complex vinyl ether with subsequent return of the thus obtained mixture in the polymerization process.

All currently known from the Urals branch of the nya engineering methods inherent to the disadvantage of they are not allowed to dispose of the resulting residual gas.

Based on the foregoing, the present invention was based on the objective to develop a method, which would be separated from the resulting residual gas valuable substances for their cost-effective re-use.

This problem is solved using the proposed in the invention method, which allows the recycling of the residual gas fractionated condensation extract the contained valuable raw materials for their subsequent material reuse.

The object of the invention is a method for containing complex vinyl ether and ethylene or ethylenevinylacetate the monomers of the copolymers by radical emulsion or suspension polymerization in an aqueous medium at an absolute pressure in the range from 5 to 100 bar, wherein upon completion of the polymerization reaction mixture drossellied with lowering the absolute pressure of 0.1-5 bar and through a multi-stage fractionated condensation with deep cooling of the residual gas Recuperat unreacted monomers.

For polymerization, it is preferable to use a mixture of vinyl acetate and ethylene, and mixtures of vinyl acetate and other mixed in nilovic esters, such as vanillaware or vinyl esters of α-branched monocarboxylic acids with 9 to 13 carbon atoms, and ethylene.

The polymerization process can be carried out in a fully continuous or periodic mode.

The polymerization process is preferably completed after the conversion of at least 95-99 wt.% monomers, which in the conditions of polymerization are in the liquid state.

In one of the preferred options proposed in the invention of the method of installation for multi-condensation feature before creating a negative pressure in the extender vacuum pump with its suction side. The advantage associated with such installation location for multistage condensation and vacuum pump, is to eliminate the change in the composition of the residual gas from entering components resulting from the polymerization and formation of side products in the vacuum pump. Thereby it is possible to avoid the influence of factors that could prevent the reuse of the original substances, such as ethylene and vinyl acetate, especially in the polymerization process.

In the following a preferred embodiment of the proposed invention in the method of installation for multi-stage condensation have a compressor after it is part of the discharge. In this embodiment, the residual gas can be exhausted from the expander compressed ethylene, coming out of the jet compressor. Thereby it is possible to avoid the above disadvantages of the vacuum pump, for example, the liquid ring vacuum pump.

As the cooling medium, it is preferable to use liquid nitrogen or liquid air with operating temperature from -180 -170°C at the corresponding absolute pressure boiling in the range of 5 to 10 bar. Nitrogen is released from the system in gaseous form at room temperature and can be used in the dispersing installation to create an inert atmosphere or may be fed into the existing factory system.

In the implementation proposed in the invention method, the residual gas is separated into individual components by fractionated condensation, separation of substances based on differences in boiling points and freezing the main components of the residual gas, such as ethylene, vinyl acetate, water and nitrogen. The table below shows the boiling point and freezing some important basic components that may be contained in the residual gas.

ComponentsBoiling point, °C Freezing point, °C
Water1000
The vinyl acetate73-93
Ethylene103-169
The ethyl acetate77-84
Methanol65-97
The acetate57-98
Acetic aldehyde20-123

The selection of the individual components of the residual gas stream by condensation occurs when the implementation of the proposed in the invention of the method on an industrial scale in a cascade of at least two, preferably three, of the condensation stages. The temperature in each of these stages of condensation should not be below freezing condensation in it component.

One of the distinguishing features proposed in the invention method is that in the first stage of condensation condense water vapor at a temperature in ENISA least 1°C, preferably at a temperature in the range from 1 to 5°C.

Another distinctive feature proposed in the invention method is that the second stage of condensation condense vinyl acetate at a temperature in the range from -90 to -60°C. the thus Obtained liquid vinyl acetate return in the polymerization process, or served in the distillation system of the production unit for production of Monomeric vinyl acetate.

A distinctive feature of the proposed invention the method also lies in the fact that in the third stage of condensation condense ethylene at a temperature in the range from -140 -100°C. thus Obtained liquid ethylene is then returned to the polymerization process.

In yet another embodiment proposed in the invention method are obtained in liquid form ethylene evaporated at an absolute pressure in the range from 1 to 20 bar and then either shrink and return to the polymerization process or serves as a starting material in the reaction circuit manufacturing unit for production of Monomeric vinyl acetate.

Recyclable residual gas depending on the pressure and temperature at which carry out specific polymerization process, has the following composition: water in an amount of from 1 to 15 vol.%, the vinyl acetate in an amount of 5 to 20 vol.% and ethylene in an amount of from 60 to 90 is b.%. Other components of the residual gas is nitrogen and is present in trace quantities acetaldehyde, methanol, methyl, and ethyl acetate. Absolute operating pressure, prevailing by throttling emulsion is from 100 to 5000 mbar. The temperature ranges from 25 to 75°C.

Below proposed in the invention method is described in more detail with reference to two technological schemes shown in figures 1 and 2.

Figure 1 shows a process scheme with recirculation of gaseous ethylene, recuperated proposed in the invention method. Figure 2 shows the technological scheme with recirculation of liquid ethylene, recuperated proposed in the invention method.

In the following description, explanations apply to both technological schemes shown in figures 1 and 2. The polymerization process [P1] can be carried out in a continuous or periodic mode. Upon completion of the polymerization reaction mixture drossellied and the resulting residual gas [1] served on the fractionated condensation with deep cooling. First, the flow of the residual gas [1] served in the first stage of condensation [W1], from which emerged in the residual gas [2] and the condensate [3] go with a temperature at least 1°C. the Residual gas [2] serves further to the second stage condensation [W2]. Of e is th second stage condensation [W2] emerged in the residual gas [4] and the condensate [5] go out with temperatures ranging from -90 to -60°C. The residual gas [4] then served in the third degree of condensation of [W3], from which emerged in the residual gas [6] and the condensate [7] go with a temperature in the range from -140 -100°C. For removal of the necessary amount of heat in each of the steps of condensing cooling using liquid nitrogen. For heat dissipation in the third stage of condensation [W3] it serves liquid nitrogen [8] in countercurrent to the residual gas [4]. The nitrogen thus completely evaporates, and for heat removal in the second stage condensation [W2] serves it in the form of gaseous nitrogen [9] in countercurrent to the residual gas [2]. From the second stage condensation [W2] gaseous nitrogen [10] leaves heated to even higher temperatures. For removal in the first stage of condensation [W1] a sufficient amount of heat to the stream of nitrogen [10] additionally mixed into liquid nitrogen [11]. The thread then cooled by gaseous nitrogen [12] let in in the first degree of condensation [W1] in countercurrent to the residual gas [1]. After exiting the first stage condensation [W1] a flow of heated nitrogen [13] can be submitted for further use. The condensate [5], which is the main component contains vinyl acetate, you can either directly be submitted to distillation in [V1] to obtain Monomeric vinyl acetate, or send in expenditure capacity is e [V2]. In the supply tank [V2] with vinyl acetate can also be fed a stream of fresh vinyl acetate [14]. From the supply tank [V2] acetate [15] then served in the polymerization process [P1]. The condensate [7] contains as its main component ethylene, pumped the appropriate pump [E1].

Further, the phase state of flow of the condensate [7] depends on whether its subsequent use in the liquid or gaseous state.

Figure 1 shows a process scheme with recirculation of gaseous ethylene. Liquid ethylene [16] pumped [E1] vaporizer [E2]. Get it from a liquid to gaseous ethylene ethylene [17] serves for the intermediate storage in a buffer tank [E3], which optionally also serve fresh ethylene [18]. From this buffer capacity of gaseous ethylene [19] are served in the designed for compression compressor [E4], which compressed them ethylene [20] served in the polymerization process [P1]. In another embodiment, the compressed ethylene [21] can be fed into the reaction system loop [V3] to obtain Monomeric vinyl acetate.

Figure 2 shows the technological scheme with recirculation of liquid ethylene. Liquid ethylene [16] pumped [E1] drive [E5]. Then liquid ethylene [22] can be pumped [E6] high pressure for additional supply pipeline [2] in the polymerization process [P1]. Fresh ethylene [18] is fed through a buffer capacity [E3] for intermediate storage of gaseous ethylene. It gaseous ethylene [19] are served in the designed for compression compressor [E4], which compressed them ethylene [20] served in the polymerization process [P1]. In the implementation proposed in the invention method, you must create conditions that, when fractionated condensation with deep cooling in accordance with the process diagrams shown in figures 1 and 2, would provide a condensation predominant part of the water in the first stage of condensation [W1]. In order to avoid icing of the heat exchanger lowest temperature of the residual gas [2] in this stage condensation should not be below +1°C. Used in this stage condensation condenser shall be designed to discharge at least 90% of the water in the liquid state in the form of a condensate [3].

In the second stage condensation [W2] the lowest temperature depending on the concentration of acetate in the flow of residual gas [2] is in the range from -90 to -60°C. Used in this stage condensation condenser shall be designed for the removal of over 99% of vinyl acetate and other specified in table 1 of hydrocarbons, with the exception of ethylene in the liquid state in the form of a condensate [5].

Depending on the requirements for material re-use the Oia ethylene, after separation of water, vinyl acetate and specified in table 1 of hydrocarbons, the following options of application of the third stage of condensation [W3] in the implementation proposed in the invention method.

In the variant with recirculation of gaseous ethylene in the third stage of condensation of [W3], in which the temperature depending on the pressure is in the range from -140 -100°C, by condensation of ethylene is separated from the nitrogen and by the subsequent evaporation at an absolute pressure in the range from 1 to 120 bar is transferred into the gaseous state [17].

In the variant with recirculation of liquid ethylene in the third stage of condensation of [W3], in which the temperature depending on the pressure is in the range from -140 -100°C, by condensation of ethylene is separated from the nitrogen and receive in a liquid state (deeply refrigerated) [22].

In a preferred embodiment, the temperature in the third stage of condensation [W3] is from -140 to -120°C.

In yet another embodiment, the process of recovery of gaseous ethylene third degree of condensation of [W3] is not used when the relative content of nitrogen in atlantageorgia fraction, i.e. in the residual gas [4], leaving the second stage condensation [W2], is not significant for the subsequent application of ethylene.

There are several discussed below possibilities of material scraps the promotion of individual fractions, obtained by carrying out proposed in the invention method.

The condensate [5]obtained in the second stage condensation [W2], consists of at least 95 wt.% of vinyl acetate and contains trace quantities of water, acetaldehyde, methanol, methyl, and ethyl acetate. The mixture of these substances can either be used in the emulsion polymerization process [P1], or to apply for distillation processing in [V1] to obtain Monomeric vinyl acetate.

The condensate [7]obtained in the third stage of condensation of [W3], contains ethylene in an amount of at least 98 wt.%. It can either be used in the emulsion polymerization process [P1], or can be directed into the reaction circuit, for example, [V3] to obtain Monomeric vinyl acetate.

The residual gas [4], obtained in the second stage condensation [W2], contains ethylene in an amount of at least 95 wt.%. It can also be used in the emulsion polymerization process [P1] or can be fed into the reaction circuit, for example, [V3] to obtain Monomeric vinyl acetate. In this embodiment, the process of recovery of gaseous ethylene third stage condensation [W3] there would be.

Proposed in the invention fractionated condensation with deep cooling using heat exchangers, preferably the casing is of tubular heat exchangers. To prevent clogging of heat exchangers and pipelines at their design should avoid having narrow slits and stagnant zones in all places, through which the residual gas and condensates.

To ensure the long life of the installation for multi-stage condensation with deep cooling of each individual stage of condensation in one of the preferred options proposed to equip a spare stage condensation with the ability of the corresponding switch to it with the "main" stage of condensation. In one particularly preferred options appropriate replacement step condensation to equip only the second stage of condensation [W2]. Availability of spare condensation stages allows for the maintenance of the "core" of the condensation stages, without stopping the operation of the entire plant for multistage condensing at its long-term operation.

Examples

Discussed below corresponds to the invention of example refers to the portion shown in figure 1. technological scheme, which corresponds to the processing of residual gas formed during copolymerization of vinyl ester and ethylene, by the three-step condensation with deep cooling. This part of the process and therefore the s are the degrees of condensation [W1]-[W3], and flows[1]-[12].

The residual gas stream [1], which contains ethylene in an amount of 75 mol.%, the vinyl acetate in the amount of 11 mol.%, water in amount of 10 mol.%, ethane in the amount of 1.5 mol.%, as well as acetaldehyde and methanol in the amount of 0.1 mol.% (N2- else), processed with a flow rate equal under normal conditions of 60 m3/h (88 kg/h), in the three-step condensation with deep cooling. The temperature of the residual gas at an absolute pressure of 600 mbar up to 40°C.

In the first stage of condensation [W1] serves the flow of residual gas [1], from which it remove heat in an amount of about 4 kW, and from the first stage condensation [W1] take away the residual gas [2] and the condensate [3] with a temperature of 5°C. the water content of the residual gas [2] is reduced by 87%, the methanol content of 42%, and acetic aldehyde - 3.4%. Obtained in the first stage of condensation of the condensate [3] consists of 97 wt.% of water, 1.7 wt.% of vinyl acetate, 0.8 wt.% of methanol and 0.1 wt.% of acetic aldehyde.

In the second stage [W2] - condensing supplied to it from the residual gas heat disperses in the amount of approximately 5.8 kW, and from the second stage of condensation is taken of the residual gas [4] and the condensate [5] with a temperature of -70°C. the vinyl acetate Content in the residual gas [4] decreases while 99.8%, the content of acetaldehyde (99%, the content of water and methane is a - 100%and ethane - 5.5%. Obtained in the second stage of condensation of the condensate [5] consists of 2.4 wt.% from the water to 97 wt.% of vinyl acetate, 0.2 wt.% of methanol and 0.4 wt.% of acetic aldehyde.

Operating temperature in the third stage of condensation [W3] is -140°C, while it by heat dissipation in the amount of 9.7 kW gain ethylene in an amount of about 55 kg/h (the content of ethylene in the feed gas is more than 99,6%). The temperature of the residual gas [6] and condensate [7] at the output of the third stage of condensation is -140°C. Obtained in the third step of condensation of the condensate [7] consists of 98 wt.% from ethylene and 1.5-2 wt.% from ethane, and contains trace amounts of vinyl acetate and acetaldehyde. Coming out of the third stage of condensation of the residual gas [6] contains an inert gaseous N2.

For removal of the above amounts of heat at appropriate stages of condensation for cooling using liquid nitrogen. For heat dissipation in the third stage of condensation [W3] it in countercurrent to the residual gas [4] serves liquid nitrogen [8] with a flow rate of about 150 kg/h at an absolute pressure of 6.5 bar and at a temperature of -175°C. the Nitrogen completely evaporates and exits the third stage of condensation in the form of gaseous nitrogen [9] with temperature -118°C. For heat removal in the second stage condensation [W2] in which it serves gaseous nitrogen [9] in countercurrent to the residual gas [2]. From the second stage condensation [W2] comes gaseous nitrogen [10], which is already heated to a temperature of +13°C. For heat dissipation in the first stage of condensation [W1] 4 kW to this stream of nitrogen gas [10] additionally mixed into liquid nitrogen [11] with a flow rate of about 30 kg/h Due to this the temperature of the flow of nitrogen [12] on the first stage of condensation [W1] could be reduced to approximately -46°C, the temperature of the nitrogen [13] at the output of the first stage of condensation is 30°C.

1. The method of obtaining contain complex vinyl ether and ethylene or ethylenevinylacetate the monomers of the copolymers by radical emulsion or suspension polymerization in an aqueous medium at an absolute pressure in the range from 5 to 100 bar, wherein upon completion of the polymerization reaction mixture drossellied with lowering the absolute pressure of 0.1-5 bar and through a multi-stage fractionated condensation with deep cooling of the residual gas Recuperat unreacted monomers, provided that in the first stage of condensation condense water vapor at a temperature in the range from 1 to 5°C, in the second stage condensation condense vinyl acetate at a temperature in the range from -90 to -60°C, and in the third stage of condensation condense ethylene at a temperature in the range from -140 -100°is.

2. The method according to claim 1, characterized in that the liquid ethylene is evaporated at an absolute pressure in the range from 1 to 20 bar and then either shrink and return in the polymerization process, or served as source material into the reaction circuit manufacturing unit for production of Monomeric vinyl acetate.

3. The method according to claim 1, characterized in that the liquid ethylene return in the polymerization process.

4. The method according to claim 1 or 2, characterized in that the liquid vinyl acetate return in the polymerization process, or served in the distillation system of the production unit for production of Monomeric vinyl acetate.

5. The method according to claim 1 or 2, characterized in that the multi-stage condensation is carried out before the vacuum pump with its suction side.

6. The method according to claim 1 or 2, characterized in that the multi-condensation is carried out after the compressor with its discharge side.

7. The method according to one of claim 1 or 2, characterized in that the polymerization process is carried out in a fully continuous or periodic mode.

8. The method according to claim 1 or 2, characterized in that the polymerization stop after turning 95-99 wt.% monomers, which in the conditions of polymerization are in the liquid state.

9. The method according to claim 1 or 2, characterized in that the polymerization using MESI of vinyl acetate and ethylene, as well as a mixture of vinyl acetate and other vinyl esters, such as vanillaware or vinyl esters of α-branched monocarboxylic acids with 9 to 13 carbon atoms, and ethylene.



 

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10 cl, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to methods of producing perfluorinated polymers with sulfo-groups and is used in production of proton conducting ion-exchange membranes. The method involves copolymerisation of tetrafluoroethylene with perfluoro(3,6-dioxa-4-methyl-7-octene)sulfonylfluoride in the medium of an organic solvent - perfluoromethyl diethylamine at temperature 50°C and pressure 2.5-5 atm. The initiator used is bis(perfluorocyclohexanoyl)peroxide.

EFFECT: invention solves the problem of increasing molecular weight of a copolymer of tetrafluoroethylene with perfluoro(3,6-dioxa-4-methyl-7-octene)-sulfonyl fluoride and replacing the ozone-depleting solvent with an environmentally safe solvent.

2 dwg, 1 tbl, 13 ex

FIELD: chemistry.

SUBSTANCE: method is realised via copolymerisation of tetrafluoroethylene (TFE) and perfluro(3,6-dioxy-4-methyl-7-octene)sulfonylfluoride (FS141) in a medium of organic solvent. Copolymerisation is carried out in a medium of solvent - 1,2-dichlorohexafluorocyclobutane (RC 316) at pressure 2.5-5 atm using bis(perfluorocyclohexanoyl)peroxide as an initiator.

EFFECT: low explosion hazard of the process and replacement of the ozone-decomposing solvent by an environmentally safe solvent.

1 cl, 1 ex, 1 tbl

FIELD: chemistry.

SUBSTANCE: method is realised via copolymerisation of tetrafluoroethylene (TFE) and perfluro(3,6-dioxy-4-methyl-7-octene)sulfonylfluoride (FS141) in a medium of organic solvent. Copolymerisation is carried out in a medium of solvent - 1,2-dichlorohexafluorocyclobutane (RC 316) at pressure 2.5-5 atm using bis(perfluorocyclohexanoyl)peroxide as an initiator.

EFFECT: low explosion hazard of the process and replacement of the ozone-decomposing solvent by an environmentally safe solvent.

1 cl, 1 ex, 1 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to a method for gas-phase polymerisation of olefins, where polymerisation takes place in a reactor having interconnected polymerisation zones. The method for gas-phase polymerisation of α-olefins CH2=CHR, where R denotes hydrogen or a hydrocarbon radical, having 1-12 carbon atoms, is realised in first and second interconnected polymerisation zones. One or more α-olefins are fed in the presence of a catalyst. Growing polymer particles pass through the first of the said zones (a pipe going upwards) under fast fluidisation conditions, comes from the said pipe and enter the second of the said polymerisation zones (pipe going downwards), through which the go down in dense form, come out of the pipe going downwards and once again enter the said pipe going upwards. The gas mixture inside the pipe going upwards is completely or partially prevented from entering the pipe going downwards. The gaseous composition inside part of the pipe going downwards is kept essentially similar to the gaseous composition in the pipe going upwards.

EFFECT: wide range of polymer compositions, obtained using a polymerisation reactor, having interconnected polymerisation zones.

7 cl, 1 dwg, 3 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method for gas-phase polymerisation of olefins, where polymerisation takes place in a reactor having interconnected polymerisation zones. The method for gas-phase polymerisation of α-olefins CH2=CHR, where R denotes hydrogen or a hydrocarbon radical, having 1-12 carbon atoms, is realised in first and second interconnected polymerisation zones. One or more α-olefins are fed in the presence of a catalyst. Growing polymer particles pass through the first of the said zones (a pipe going upwards) under fast fluidisation conditions, comes from the said pipe and enter the second of the said polymerisation zones (pipe going downwards), through which the go down in dense form, come out of the pipe going downwards and once again enter the said pipe going upwards. The gas mixture inside the pipe going upwards is completely or partially prevented from entering the pipe going downwards. The gaseous composition inside part of the pipe going downwards is kept essentially similar to the gaseous composition in the pipe going upwards.

EFFECT: wide range of polymer compositions, obtained using a polymerisation reactor, having interconnected polymerisation zones.

7 cl, 1 dwg, 3 tbl, 3 ex

FIELD: organic chemistry, polymers, fertilizers.

SUBSTANCE: invention relates to new anionic, biodegradable, water-soluble polymers and their derivatives that can be used in agriculture. Invention describes a water-soluble biodegradable polymer comprising repeating dicarboxylic polymeric links consisting of at least two different fragments taken among fragment group A, B and C (see appendix). Above indicated polymeric links are formed by fragments A, B and C. Also, invention relates to a method for its preparing. Invention describes a fertilizer wherein its particles are in the tight contact with the indicated polymer. Also, invention discloses a method for improving the plant growth by using the composition comprising the indicated polymer, a method for reducing nitrogen evolving from the fertilizer by applying the indicated polymer, a method for enhancing availability of phosphorus involving a stage for applying the indicated polymer on fertilizer. Also, invention describes the composition for enhancing the plant growth, the priming product wherein the primer in the tight contact with polymer, and a method for enhancing abrasive stability of the solid fertilizer. Polymers prepared by such method show the significant effect on enhancing availability of phosphorus from ammonium-phosphorus fertilizers, promote to the plant growth enhancing and enhance the abrasive stability of fertilizer particles.

EFFECT: valuable properties of polymers.

16 cl, 7 tbl, 26 ex

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