RU2508283C1 - Method of producing hydrocarbon propellants - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method of producing hydrocarbon propellants involves combined drying and cleaning of hydrocarbon material and separating the hydrocarbon propellant composition. The hydrocarbon material used is propane, a butane fraction or isobutane or n-butane or propane or a mixture of propane and n-butane. Drying and cleaning is carried out by passing the material in liquid-phase through sorbents in three series-arranged adsorbers. The first adsorber on the process path is filled with aluminium oxide, the second adsorber is filled with zeolite NaA and the third adsorber is filled with zeolite NaX. The given propellant composition is obtained after the third adsorber, wherein if the hydrocarbon material used is a mixture of propane and n-butane, the given propellant composition is obtained in a mixer by mixing propane and n-butane in weight ratio of 0.96.

EFFECT: obtaining a product of high quality with low content of moisture and sulphur compounds, low operational and capital costs on implementing the process.

2 dwg, 1 tbl

Description

Technical field

This invention relates to the chemical industry, specifically to a technique for producing environmentally friendly hydrocarbon gases - propellants used as a propellant gas for aerosol containers. A propellant gas is a liquefied hydrocarbon gas in the form of fractions and (or) their mixtures (compositions) and differs in saturated vapor pressure and fractional composition. The quality of drying and purification of the displacer gas determines its use in those industries where the gas requirements for the content of mercaptans and moisture are very high (perfumes and cosmetics, medical aerosols, production of car cosmetics, foam, paint and varnish products).

State of the art

The closest in its technical essence and the achieved technical result is the invention "Method for producing hydrocarbon propellants" [1], [patent RU No. 2115684, C1, publication date 07/20/1998]. According to this invention, in a method for producing hydrocarbon propellants, including rectification of hydrocarbon raw materials, purification, deodorization and drying, a mixture of hydrocarbons of a given composite composition with an excess pressure of saturated vapors corresponding to an excess pressure of saturated vapors of hydrocarbon propellants is isolated and subjected to preliminary purification and deodorization in the rectification process. activated carbon, and drying is carried out on synthetic zeolites. Moreover, drying and purification is carried out by passing a mixture of hydrocarbons through sequentially placed layers of zeolites NaA, CaA and NaX. When this regeneration is carried out with nitrogen or dried hydrocarbon gas.

As a raw material for the production of propellants, a C _{3 + 8} hydrocarbon mixture is used.

The main disadvantages of the prototype are:

- the use of layer-by-layer filling of zeolites NaA, CaA and NaX in adsorbers leads to mixing of the layers during adsorption drying and purification, which affects the selectivity of the process and, accordingly, the purity of the product propellant;

- the use of coal adsorbers increases the technological complexity and cost of installation;

- the use of pure nitrogen and adsorption blocks as a regeneration gas leads to high production costs.

The objective of the proposed method is to create an environmentally friendly technology for the production of hydrocarbon propellants, which will allow to obtain high quality products with low moisture and sulfur content up to 0.0001% and significantly reduce operating and capital costs for the implementation and implementation of the process.

Disclosure of invention

The problem is achieved in that in the method for producing hydrocarbon propellants, including drying and purification of hydrocarbon feed, separation of the hydrocarbon propellant composition, in contrast to the prototype, propane uses a butane fraction, or isobutane, or n-butane, or n-butane, drying and purification is carried out by passing raw materials in the liquid phase through sorbents in three sequentially arranged adsorbers. The first adsorber during the process is filled with alumina, the second adsorber during the process is filled with NaA zeolite, and the third adsorber during the process is filled with NaX zeolite. The desired propellant compositions are obtained after the third adsorber downstream or by mixing the resulting n-butane and propane compositions in a weight ratio of 0.96.

The proposed method for producing hydrocarbon propellants is carried out on the installation, which is presented in the drawings, where Fig. 1 shows a schematic diagram of a drying and cleaning unit, and in Fig. 2 a schematic diagram of a unit for producing a propellant composition.

Four adsorber units are included in the drying and cleaning unit. Block No. 1 is designed for drying and purifying the propane butane fraction. Block No. 2 is designed for drying and purification of isobutane. Block No. 3 is designed for drying and purifying n-butane. Block No. 4 is designed for drying and purifying propane. The piping tying scheme provides for the shutdown of any adsorber for the regeneration process. The regeneration process of the adsorbers in each block is carried out alternately. For the regeneration, the vapor phase of the purified hydrocarbon feed (propane butane fraction (PBP), isobutane, n-butane or propane) is used. The vapor phase is taken from the storage tank of the cleaned component propellant, compressed to a pressure of 0.6 MPa, and fed into the regenerated adsorber for the cooling process. The vapor phase of the propellant component, passing through a cooled adsorber, partially heats up and enters the regenerative heat exchanger. The recuperative heat exchanger is designed to recover heat from the regeneration gas. After the recuperative heat exchanger, the vapor phase of the propellant component is heated in the furnace to the regulated temperature and enters the upper part of the regenerated adsorber. The regeneration gas after the regenerated adsorber passing through the pipe part of the regenerative heat exchanger is partially cooled, giving off heat to the gas entering the regeneration. In winter, a regenerative heat exchanger is used to heat the hydrocarbon component supplied to the adsorption to 20 ° C, where it is heated by cooling the regeneration gas. In the summer, heating the hydrocarbon component before adsorption is not required, the heat exchanger is used for the final cooling of the regeneration gas due to the evaporation of the hydrocarbon component in the annulus. The heat exchanger is included in the work together with the separator. Cooled, moisture-containing and desorbed impurities regeneration gas enters a special container for collecting regeneration gas. Settled water from the recovery gas recovery tank is periodically drained. Dried and cleaned propellant components are pumped to the unit for producing the hydrocarbon component composition, which consists of the receiving tanks of the pumps and the mixer. As a mixer to obtain a commodity propellant composition from individual components - propane and butane, a turbo mixer is used.

The components of the hydrocarbon feed are metered into the mixer by pumps, the required amount of the component supplied to the mixing is set by the mass flow meter. As a result of the displacement, a propellant composition is formed with a certain saturated vapor pressure.

The drying and cleaning unit contains a container 1, a drain with which is connected to a pump 2, the discharge pipe of which through a heat exchanger 6 is connected to the entrance to the lower part of the adsorber 3. The output of the adsorber 3 is connected to the entrance to the upper part of the adsorber 4. The output of the adsorber 4 is connected to the entrance to the lower part of the adsorber 5. Adsorbers 3, 4, 5 work sequentially for deep drying and fine cleaning of the components of hydrocarbon propellants with adsorbents placed in them. The adsorber 3 is filled with active alumina. The adsorber 4 is filled with NaA zeolite. The adsorber 5 is filled with zeolite NaX. The hydrocarbon mixture exits from adsorbers 3, 4, 5 are connected to a filter 14 for fine purification of propellant components from zeolite dust, the outlet of which is connected to a finished product pipeline - a hydrocarbon propellant, which is sent to a tank 16. The circuit provides four adsorption purification units consisting of adsorbers 3, 4, 5 in order to disable any block or adsorber for the regeneration process. In this case, one of the blocks continues to operate in the mode of drying and purification of the hydrocarbon mixture. The pipeline 17 supplying regeneration gas to the upper part of the adsorbers 3, 4, 5 is connected to the regeneration gas preparation unit. As the regeneration gas, the vapor phase of the hydrocarbon propellant from the tank 16 is used, which from its upper part enters the compressor 15, is compressed to 0.6 MPa and enters through the pipeline 18 to the lower part of the adsorbers 3, 4, 5 to carry out the cooling process of the adsorbent, which passed high temperature regeneration. The vapor phase of the hydrocarbon propellant is partially heated and cools the hot adsorbent in the adsorbers 3, 4, 5 and enters from the top of the adsorbers to a recuperative heat exchanger 8. The recuperative heat exchanger is connected by a pipe to the furnace 9, in which the regeneration gas is heated to the operating temperature and piped to 17 the upper part of the adsorbers 3, 4, 5. The outlet of the regeneration gas from the lower part of the adsorbers 3, 4, 5 is connected to the filter 7, intended for cleaning from zeolite dust. The purified regeneration gas is connected through a pipeline to a recuperative heat exchanger 8 for partial cooling and is sent to an air cooler 10 for final cooling. The outlet from the air cooler is connected by a pipe to a tank 12 for collecting regeneration gas. In winter, the regeneration gas from the lower part of the adsorbers 3, 4, 5 is sent to a recuperative heat exchanger 6 to recover heat and preheat the hydrocarbon mixture entering the adsorption. The outlet of the heat exchanger 6 is connected by a pipe to a tank 12, which is connected by a drain line to the pump 13. The pipe from the pump 13 is designed to pump out the liquid hydrocarbon moist and contaminated propellant component for the needs of a gas station. The heat exchanger 6 is connected by pipelines to the separator 11.

The hydrocarbon component composition production unit contains containers 19, 21, 23, and 25 into which, from the pumps 18a of the adsorption units of the drying and purification units 1, 2, 3, and 4, are pumped, purified and dried components for preparing the compositions come through pipelines. The propane butane fraction from unit No. 1 enters the tank 19, the discharge of the tank 19 is connected to the pump 20, the discharge pipe of which is connected by a pipe to the inlet of the tank 28 for collecting commodity propellant grade No. 1, with a saturated vapor pressure of 0.3-0.4 MPa. Isobutane from block No. 2 enters the tank 21, the drain of the tank 21 is connected to the pump 22, the discharge pipe of which is connected by a pipe to the inlet of the tank 29 for collecting commodity propellant grade 2, with a saturated vapor pressure of 0.21-0.26 MPa. H-butane from unit No. 3 enters the vessel 23, the discharge of the vessel 23 is connected to the pump 24, the discharge pipe of which is connected by a pipe to the inlet of the vessel 30 for collecting commodity propellant grade No. 3, with a saturated vapor pressure of 0.11-0.16 MPa. Propane from block No. 4 enters the vessel 25, the discharge of the vessel 25 is connected to a pump 26, the discharge pipe of which is connected by a pipe to the inlet of the vessel 32 for collecting commodity propellant grade No. 4, with a saturated vapor pressure of 0.72-0.83 MPa. At the inlet of the mixer 27, butane is supplied through a pipeline from the pump 24, and propane after the pump 26. The outlet from the mixer 27 is connected to a tank 31 for collecting commodity propellant grade No. 5, with a saturated vapor pressure of 0.43-0.47 MPa.

Installation works as follows.

The liquid component of the hydrocarbon propellant is taken into the tank 1 and pump 2 is fed into the lower part of the adsorber 3, which is filled with active alumina for general use, intended for primary drying of the propane butane fraction. From the upper part of the adsorber, the hydrocarbon component enters adsorber 4, which is filled with NaA zeolite for deep drying. In the adsorber 5 filled with NaX zeolite, the component is deeply purified from hydrogen sulfide, mercaptans and other impurities. The obtained hydrocarbon component from the adsorber 5 is cleaned in the fine filter 14 from zeolite dust and enters the tank 16, designed to collect the hydrocarbon component. The scheme provides four adsorption purification units, consisting of adsorbers 3, 4, 5, in order to disable any unit or adsorber for the regeneration process.

The regeneration of adsorbents in adsorbers 3, 4, 5 is carried out by the vapor phase of the hydrocarbon component from the tank 16, which is compressed from its upper part by a compressor 15 to 0.6 MPa and fed to the lower part of the adsorbers 3, 4, 5 to carry out the cooling process of the adsorbent that has passed the high-temperature regeneration. The vapor phase of the hydrocarbon component of the propellant is partially heated and cools the hot adsorbent in the adsorbers 3, 4, 5 and flows from the upper part of the adsorbers to the regenerative heat exchanger 8. The regenerative heat exchanger is designed to utilize the heat of the regeneration gas. After the recuperative heat exchanger, the vapor phase of the hydrocarbon component of the propellant is heated in the furnace 9, to the operating temperature of 150-300 ° C and enters the upper part of the adsorbers 3, 4, 5. The regeneration gas after the regenerated adsorbers is sent to the filter 7, intended for cleaning from zeolite dust and it is then sent to a recuperative heat exchanger 8, partially cooled, transferring heat to the gas entering the regeneration. After the recuperative heat exchanger, the regeneration gas is finally cooled in the air cooler 10 and enters the tank 12 for collection and disposal. In winter, to heat the regeneration gas supplied to the adsorption unit, after the air cooler 10, it is sent to a regenerative heat exchanger 6, where it is heated by cooling the regeneration gas. The heat exchanger 6 is included in the work together with the separator 11.

Cooled, containing moisture and desorbed impurities, the regeneration gas enters a special tank 12 for collecting regeneration gas. The settled water from the tank 12 is periodically drained. The liquid hydrocarbon component is pumped out by a pump 13 for the needs of a gas station.

Dried and refined hydrocarbon components: propane butane fraction, isobutane, n-butane and propane are fed to the unit for producing the hydrocarbon component composition in containers 19, 21, 23 and 25 from the adsorption units of the drying and purification units 1, 2, 3 and 4 for preparing the compositions . The butane fraction from block No. 1 enters the tank 19 and is pumped to the tank 28 to the tank 28 to collect brand No. 1 commercial propellant. In the tank 21 isobutane enters from block No. 2 and the pump 22 is fed into the tank 29 to collect trademark propellant brand No. 2. In the tank 23 enters n-butane from the block No. 3 and the pump 24 is fed into the tank 30 to collect trademark propellant brand No. 3. The propane 25 enters propane from block No. 4 and is pumped into a container 32 to a container 32 for collecting commercial grade propellant No. 4. At the inlet of the mixer 27, butane is supplied through a pipeline from the pump 24, and propane after the pump 26. The outlet from the mixer 27 is connected to a tank 31 for collecting commodity propellant brand No. 5.

When used as a mixer for the preparation of a propellant composition of a turbo mixer, a Sulzer S-4000 mixer is used.

Examples 1-5 show the implementation of the present invention by a method for producing hydrocarbon propellants using various options for the composition of the propellant from the components of the hydrocarbon feedstock.

Example 1. This example illustrates the implementation of the method for producing a hydrocarbon propellant based on a hydrocarbon feedstock - propane butane fraction (PBP).

To obtain a hydrocarbon propellant with an excess vapor pressure of 0.3-0.4 MPa, which is necessary for aerosol packaging, the propane-butane fraction is dried and purified from sulfur impurities.

A method of producing hydrocarbon propellants is implemented on the installation (figure 1 and figure 2).

The liquid component of the hydrocarbon propellant - propane butane fraction (PBP) is taken into tank 1 and pump 2 is fed into the lower part of the adsorber 3, which is filled with general-purpose active alumina intended for primary drying of the PBP fraction. From the upper part of the adsorber, the hydrocarbon component enters adsorber 4, which is filled with NaA zeolite for deep drying. In the adsorber 5 filled with NaX zeolite, the component is deeply purified from hydrogen sulfide, mercaptans and other impurities. The obtained hydrocarbon propellant from the adsorber 5 is cleaned in the fine filter 14 from zeolite dust and enters the tank 16, designed to collect the hydrocarbon component. The scheme provides four adsorption purification units, consisting of adsorbers 3, 4, 5, in order to disable any unit or adsorber for the regeneration process.

The regeneration of adsorbents in adsorbers 3, 4, 5 is carried out by the vapor phase of the hydrocarbon component from the tank 16, which is compressed from its upper part by a compressor 15 to 0.6 MPa and fed to the lower part of the adsorbers 3, 4, 5 to carry out the cooling process of the adsorbent that has passed the high-temperature regeneration. The vapor phase of the hydrocarbon component of the propellant is partially heated and cools the hot adsorbent in the adsorbers 3, 4, 5 and flows from the upper part of the adsorbers to the regenerative heat exchanger 8. The regenerative heat exchanger is designed to utilize the heat of the regeneration gas. After the recuperative heat exchanger, the vapor phase of the hydrocarbon component of the propellant is heated in the furnace 9, to the operating temperature of 150-300 ° C and enters the upper part of the adsorbers 3, 4, 5. The regeneration gas after the regenerated adsorbers is sent to the filter 7, intended for cleaning from zeolite dust and it is then sent to a recuperative heat exchanger 8, partially cooled, transferring heat to the gas entering the regeneration. After the recuperative heat exchanger, the regeneration gas is finally cooled in the air cooler 10 and enters the tank 12 for collection and disposal. In winter, to heat the regeneration gas supplied to the adsorption unit, after the air cooler 10, it is sent to a regenerative heat exchanger 6, where it is heated by cooling the regeneration gas. The heat exchanger 6 is included in the work together with the separator 11.

Cooled, containing moisture and desorbed impurities, the regeneration gas enters a special tank 12 for collecting regeneration gas. The settled water from the tank 12 is periodically drained. The liquid hydrocarbon component is pumped out by a pump 13 for the needs of a gas station.

The dried and purified propane butane fraction is fed to the unit for producing the hydrocarbon component composition in the tank 19 from the adsorption unit No. 1 of the drying and purification unit and pump 20 is fed into the tank 28 for collecting commodity grade 1 propellant.

Example 2. This example illustrates the implementation of the method for producing a hydrocarbon propellant analogously to example 1, characterized in that isobutane is used as a raw material for the production of a hydrocarbon propellant, with an excess vapor pressure of 0.21-0.26 MPa required for aerosol packaging.

Dried and purified isobutane enters the unit for obtaining the composition of the hydrocarbon component in the tank 21, from the adsorption unit No. 2 of the drying and purification unit and pump 22 is fed into the tank 29 for collecting commodity grade 2 propellant.

Example 3. This example illustrates the implementation of the method for producing a hydrocarbon propellant analogously to example 1, characterized in that n-butane is used to obtain a hydrocarbon propellant with an excess vapor pressure of 0.11-0.16 MPa required for aerosol packages.

Dried and purified n-butane enters the unit for obtaining the composition of the hydrocarbon component in the tank 23, from the adsorption unit No. 3 of the drying and purification unit and pump 24 is fed into the tank 30 for collecting commodity grade 3 propellant.

Example 4. This example illustrates the implementation of the method for producing a hydrocarbon propellant analogously to example 1, characterized in that propane is used to obtain a hydrocarbon propellant with an excess vapor pressure of 0.72-0.83 MPa required for aerosol packages.

Dried and purified propane enters the unit for obtaining the composition of the hydrocarbon component in the tank 25, from the adsorption unit No. 4 of the drying and purification unit and pump 26 is fed into the tank 32 for collecting commodity grade 4 propellant.

Example 5. This example illustrates the implementation of the method for producing hydrocarbon propellants similarly to examples 3 and 4, characterized in that the desired propellant composition with an excess vapor pressure of 0.43-0.47 MPa is obtained in a mixer by mixing propane and n-butane with mass a ratio of 0.96.

Dried and purified propane enters the unit for producing the hydrocarbon component composition in the tank 25, from the adsorption unit No. 4 of the drying and purification unit and is fed into the collector of the mixer 27 with the pump 26. The dried and purified n-butane enters the unit for producing the hydrocarbon component composition in the tank 23, from the adsorption unit No. 3 of the drying and cleaning unit and the pump 24 is supplied to the collector of the mixer 27. The flow of propane and butane are controlled by mass flowmeters. The mass ratio of propane to butane at the inlet to the mixer is 0.96. The finished composition from the mixer 27 is fed into a container 31 for collecting commercial grade 5 propellant.

The quality of hydrocarbon propellants is shown in table 1.

Table 1 Example No. Saturated vapor overpressure, MPa Mass fraction of hydrogen sulfide and mercaptan sulfur,% Mass fraction of nonvolatile substances,% Mass fraction of water,% Smell one 2 3 four 5 6 one 0.30-0.40 0,0003 0.02 0.0001 Corresponds to the smell of the reference sample 2 0.21-0.26 0.0001 0.02 0.0001 Corresponds to the smell of the reference sample one 2 3 four 5 6 3 0.11-0.16 0.0001 0.02 0.0001 Corresponds to the smell of the reference sample four 0.72-0.83 0,0002 0.02 0.0001 Corresponds to the smell of the reference sample 5 0.43-0.47 0,0003 0.02 0.0001 Corresponds to the smell of the reference sample Prototype

Achievable technical result

The advantage of the claimed installation over the prototype are:

- drying of high quality hydrocarbon propellant with a low water content of up to 0.0001%;

- purification of high quality hydrocarbon propellant with a low content of sulfur compounds up to 0.0001%;

- implementation of the principle of comprehensive deep drying and purification of raw materials. Drying and purification of the hydrocarbon mixture occurs in three adsorbers connected in series;

- a loading scheme is proposed in the adsorber unit: the first adsorber along the way is filled with active alumina intended for primary drying of the hydrocarbon mixture; the second adsorber downstream is filled with NaA zeolite intended for deep drying of the hydrocarbon mixture; the third adsorber is filled with NaX zeolite, intended for deep purification of a hydrocarbon mixture from hydrogen sulfide, mercaptans and other impurities.

Claims (1)

A method for producing hydrocarbon propellants, including drying and purification of hydrocarbon feed, isolating a hydrocarbon propellant composition, characterized in that the propane is butane fraction or isobutane, or n-butane, or propane, or a mixture of propane and n-butane, drying and purification is carried out by passing raw materials in the liquid phase through sorbents in three sequentially arranged adsorbers; the first adsorber is filled with alumina during the technological process and the second is In the other process, the adsorber is filled with NaA zeolite, and the third adsorber is filled with NaX zeolite during the technological process, the desired propellant composition is obtained after the third adsorber, and if a mixture of propane and n-butane is used as the hydrocarbon feed, the desired propellant composition is obtained in the mixer by mixing propane and n-butane with a mass ratio of 0.96.

Images