RU2620266C1 - Method of processing oil wastes based on oil slime, fuel oil or their mixture with production of water-emulsion fuel - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: method for processing oily wastes based on oil slime, fuel oil or a mixture thereof to produce a water-emulsion fuel includes heating liquid oily wastes, cleaning followed by feeding a purified mixture of hydrocarbons with water for three-stage mixture homogenization in a vibro-cavitation homogenizer along with simultaneous feeding a coal fraction from 15 to 30% of the flow rate of the supplied liquid to produce hydrated fuel with a relative centrifugal acceleration of the rotor of not less than 1200 g and with a gap between the rotor and the stator of not more than 0.25 mm. The method is characterised in that, in the process of the three-stage homogenization of hydrocarbon mixture in the vibro-cavitation homogenizer, the fine powder is uniformly supplied as a coal fraction. The powder is solid waste obtained by thermal processing of rubber and tire wastes during pyrolysis in the absence of oxygen at a temperature of 500-1000°C. Simultaneously, at the first stage of the vibro-cavitation homogenizer, 0.1-2% of magnesium oxide and 0.1-1.0% of low alcohols of the total amount of solid waste are added to the solid waste.

EFFECT: obtaining a stable fuel emulsion, which is used as a boiler fuel, the combustion fuel provides a lower content of carbon monoxide and nitrogen oxides, the method ensures utilisation of pyrolysis waste.

1 tbl, 4 ex

Description

The invention relates to the field of oil production and oil refining industry, in particular to technological processes for the processing of oily waste (oil sludge or fuel oil), and can be used for their disposal in order to obtain a water-emulsion (hydrated) fuel.

A known method of processing liquid sludge into hydrated fuel according to patent No. 2535710 dated 09/27/2014, which consists in the fact that the purified heated mixture of hydrocarbons with water is fed into a working tank with separation of at least two streams. Separated streams for their homogenization are continuously fed into a vibro-cavitation homogenizer with a difference in the flow rate of one of the flows in relation to another of at least 1.5. Homogenization is carried out in a vibro-cavitation homogenizer with a rotating rotor with a perforated surface and a fixed stator with a specific mixture flow rate of not more than 2.5 g / cm ² of the rotor working surface per second and its peripheral rotation speed of at least 20 m / s. The processing is carried out three times: the primary processing is carried out until a fuel emulsion of hydrated fuel is obtained with a droplet size of water not more than 15 microns, repeated treatments are carried out to obtain water droplets with a size of not more than 5 microns. The invention improves the stability of the emulsion of hydrated fuel.

A known method of processing liquid oily waste according to the patent No. 2566306 from 10.20.2015.

The essence of the method lies in the fact that they carry out the heating of the flooded oil sludge to a temperature of 60-95 ° C, cleaning by filtration using a vibrating screen with a mesh size of 1-4 mm, separating sand in a hydrocyclone or by settling and feeding the resulting mixture of hydrocarbons with water into a working tank . From the working tank, the mixture is continuously fed into a vibro-cavitation homogenizer with a rotating working rotor and a perforated surface, and a stationary working element stator, while the circulation of the mixture of hydrocarbons with water through the vibro-cavitation homogenizer is at least three times. Simultaneously with the liquid mixture, a fine fraction of coal with a particle size of not more than 3 mm is uniformly fed into the homogenizer inlet pipe. At the same time, during the first pass through the vibro-cavitation homogenizer, the coal fraction is supplied in an amount of 5-10% of the flow rate of the supplied liquid mixture, during the second pass, the same amount of the coal fraction is added and also a similar amount of the coal fraction is fed during the third pass through the vibro-cavitation homogenizer.

Thus, the circulation of the resulting mixture through a vibrocavitation homogenizer is at least three times, and the content of the coal fraction is up to 15-30% of the hydrated fuel. The high rotor speed creates a centrifugal force that throws the mixture of liquid and solid phases onto the stator walls with high acceleration, not less than 1200 g. In this case, primary crushing of the solid phase into small fractions, less than 0.25 mm in the gap between the rotor and stator, which is not more than 0.25 mm, ensures the formation of a liquid film containing carbon dust, the thickness of this film does not exceed 0.25 mm . Intensive crushing of the liquid and solid phase mixture occurs in this film, which circulates along the circuit between the vibrocavitation homogenizer and the capacity of the initial mixture until a finely dispersed emulsion is formed, with a particle size of water and coal within 3-5 microns. The presence of solid particles in the emulsion contributes to its stability, as they prevent the coagulation of small drops of water.

The proposed method for processing a liquid mixture using a vibro-cavitation homogenizer, with the above-mentioned operating parameters, allows to obtain stable and structured fine emulsions based on heavy fuels and oil sludges with a small size of water droplets and coal particles, uniformly distributed over the volume of water-based emulsion fuel.

The disadvantages of the developed method include the presence of two complex operations for the preparation of coal chips, namely, cleaning from inorganic components, grinding to the required size and separation of the desired fraction.

The objective of the invention is to develop a method for producing highly efficient water-based emulsion fuel from oily waste based on oil sludge, fuel oil or a mixture thereof using a coal fraction based on solid waste rubber and tires.

The technical result from the use of the invention is to simplify the technology for producing water-based fuel with improved operational, environmental parameters and the possibility of waste disposal.

The problem is solved and the technical result is achieved by the fact that a method for processing oily waste based on oil sludge, fuel oil or a mixture thereof to produce an aqueous emulsion fuel includes heating liquid oily waste, purification, followed by supplying a purified mixture of hydrocarbons with water to triple homogenization of the mixture in a vibro-cavitation homogenizer with simultaneous supply coal fraction in an amount of from 15 to 30% of the flow rate of the supplied liquid to obtain hydrated fuel at a relative centrob intermeshing rotor acceleration is not less than 1200g, and with a gap between the rotor and the stator is not more than 0.25 mm.

At the same time, during the triple homogenization of the hydrocarbon mixture, a uniformly coal fraction is fed into the vibro-cavitation homogenizer, which is solid waste (coke) obtained by thermal processing of rubber and tire waste during pyrolysis in the absence of oxygen at a temperature of 500-1000 ° С, while adding at the first the passage of the homogenizer to solid waste 0.1-2% magnesium oxide and 0.1-1.0% lower alcohols from the total amount of solid waste.

Widespread thermal methods of disposal of waste rubber and tires, which include pyrolysis and burning. http://www.tkomplex.ru/en/products/pirotex at the pyrolysis recycling plant Pirotex: processing of tires, tires, rubber goods, plastics, PET, polyethylene, oil sludge, used oils.

As a result of pyrolysis, substances are obtained that resemble oil cracking products and, therefore, are a valuable raw material for petrochemical industries.

Depending on the design of technological equipment, both crushed rubber waste (separated from metal) and whole tires can be pyrolyzed. Pyrolysis occurs in the absence of oxygen at a temperature of 500-1000 ° C. The resulting product is a fine powder, which when used as a coal fraction does not require additional grinding.

Table 1 below shows the characteristics of the solid waste obtained by the thermal method of rubber waste disposal.

Currently, waste products for rubber and tires practically do not find qualified use due to the fact that they have quite a lot of impurities and an unstable composition. Our studies have shown that such substances can be successfully used as components of boiler fuel provided that they are evenly distributed in the composition and the particle size is not more than 50 microns. Both of these conditions are successfully solved using vibro-cavitation technology for the preparation of fuel compositions, given that in most cases the particle size of the product does not exceed a few microns.

When using carbon and oily waste as fuel components, a significant amount of sulfur and its compounds gets into the composition. Given the increasing requirements of environmental standards, it is advisable to neutralize them to reduce the content of sulfur oxides in flue gases. Our attention was drawn to the method of using magnesium oxide additives in the combustion of fuel oil. According to calculations, its content in the fuel depends on the sulfur content in the original fuel and the operating conditions of the boiler plant and is 0.1-2% of the mass of fuel. The required amount of magnesium oxide in the composition depends on the type of fuel and the design features of the boiler installation and is specified during operation based on the results of the analysis of flue gases.

The process of preparing suspensions includes the separation of agglomerates and aggregates of powder particles into primary particles, displacement of the absorbed air, wetting and enveloping the particles with a dispersed medium, uniform distribution of components throughout the composition. In the ideal case, each primary particle released upon dispersion also stabilizes against re-aggregation. The advantages inherent in the powder during its production (true dispersion) may be lost if the powder particles are not properly dispersed and stabilized in the substrate.

Of all the variety of technologies for producing suspensions, in our opinion, the vibro-cavitation technology is optimal. In this case, not only the destruction of bonds in the aggregates is achieved, but also the removal of particles from each other at significant distances. At the same time, the requirements for the reliability of stabilization of powder particles are somewhat reduced due to the formation of steric obstacles from the solvate layers of the dispersion medium molecules that prevent adhesion. It should be noted that such systems are not suitable for long-term storage. However, in this case, an additional effect on the quality of dispersion, reducing the time of the working cycle can be achieved by introducing surfactants into the system that improve the lyophilizing and stabilizing effect of the dispersion medium.

Currently, to increase the stability of suspensions, various methods of modifying the surface of the dispersed phase are used: irradiation, stress, grafting organic radicals on active centers, grinding in the presence of surfactants, heat and moisture treatment, etc. At the same time, researchers are striving to create optimal ones from the point of view of one or another the technological process of conditions for changing the nature of the surface of the solid phase, primarily its lyophilicity, given the wetting ability of the dispersion medium, its olyarnosti, especially education koagulyatsinnyh contacts between the particles of polydisperse and multimineral components.

1. With manual stirring of the investigated components of the suspension, a significant amount of particle aggregates remains.

2. The use of vibro-cavitation technology for the preparation of suspensions makes it possible to disaggregate conglomerates of particles and improve the distribution of the dispersed phase over the volume of the composition.

The experiments showed that the quality of the studied compositions can be improved by using additional components, such as lower alcohols. This effect is manifested when the alcohol content in an amount of not less than 0.1% of the amount of the carbon component. An increase in the percentage of alcohol of more than 1% practically does not lead to an improvement in the dispersion of the solid phase.

Below are examples of the preparation of aqueous emulsion fuels using the developed technology.

EXAMPLE 1

As oil-containing waste - NSO used flooded oil sludge, taken from map No. 2, bush 56 of the South Surgut field, the surface layer. Oil sludge (kinematic viscosity according to GOST 33-2000 is 64 cSt, oil content 82.7% (mass.), Water 9.2% (mass.), Mechanical impurities 8.1% (mass.)) Are heated to 65 ° C , subjected to cleaning through a mesh with mesh size of 1 mm and a hydrocyclone.

Then this mixture of hydrocarbons with water, in the amount of 6000 kg, is sent to the working tank and then fed with a flow rate of 6000 kg per hour into the vibro-cavitation homogenizer at a rotor speed of rotation, creating a centrifugal acceleration of 1600g, and the gap between the rotor and the stator, which is 0.25 mm The film thickness in which dispersion occurs in the specified gap will be 0.25 mm. At the same time, solid waste (coke), obtained by thermal methods of recycling rubber and tire waste during pyrolysis in the absence of oxygen at a temperature of 500-1000 ° С, is introduced into the pipeline supplying a mixture of hydrocarbons with water to the homogenizer (the composition of solid waste is given in table 1 ), in an amount up to 30% of the amount of the supplied liquid mixture. Simultaneously with the solid waste in the first pass serves 0.1% of magnesium oxide and 1.0% of lower alcohols of the total amount of waste supplied. The emulsification process is carried out in three passes. In the first pass, the coal fraction is introduced in an amount of -10% of the flow rate of the supplied liquid mixture, i.e. 600 kg / h In the second pass, the same amount is added, i.e. another 600 kg / h. A similar amount is served during the third pass of the mixture through a vibro-cavitation homogenizer. Thus, the total amount of coal fraction introduced into the liquid mixture in three passes is 1800 kg.

After four months of storage, the maximum droplet size does not exceed 10 microns, which makes it possible to obtain a stable fuel emulsion and use the resulting fuel as a boiler.

EXAMPLE 2

As oil-containing waste - NSO used flooded oil sludge, taken from map No. 2, bush 56 of the South Surgut field, the surface layer. Oil sludge (kinematic viscosity according to GOST 33-2000 is 64 cSt, oil content 82.7% (mass.), Water 9.2% (mass.), Mechanical impurities 8.1% (mass.)) Are heated to 65 ° C , subjected to cleaning through a mesh with mesh size of 1 mm and a hydrocyclone.

Then this mixture of hydrocarbons with water, in the amount of 6000 kg, is sent to the working tank and then fed with a flow rate of 6000 kg per hour into the vibro-cavitation homogenizer at a rotor speed of rotation, creating a centrifugal acceleration of 1600g, and the gap between the rotor and the stator, which is 0.25 mm The film thickness in which dispersion occurs in the specified gap will be 0.25 mm. At the same time, solid waste (coke), obtained by thermal methods of recycling rubber and tire waste during pyrolysis in the absence of oxygen at a temperature of 500-1000 ° С, is introduced into the pipeline supplying a mixture of hydrocarbons with water to the homogenizer (the composition of solid waste is given in table 1 ), in an amount up to 30% of the amount of the supplied liquid mixture. At the same time as solid waste, 1.0% magnesium oxide and 0.5% lower alcohols are fed from the amount of waste fed. The emulsification process is carried out in three passes. In the first pass, the coal fraction is introduced in an amount of -10% of the flow rate of the supplied liquid mixture, i.e. 600 kg / h In the second pass, the same amount is added, i.e. another 600 kg / h. A similar amount is served during the third pass of the mixture through a vibro-cavitation homogenizer. Thus, the total amount of coal fraction introduced into the liquid mixture in three passes is 1800 kg.

After four months of storage, the maximum droplet size does not exceed 10 microns, which makes it possible to obtain a stable fuel emulsion and use the resulting fuel as a boiler.

EXAMPLE 3

As an oil-containing waste, the NCO used flooded oil sludge taken from map No. 1-2, Neftegorsk (kinematic viscosity 86 cSt, oil product content 68% (mass.) Water content 32% (mass.)). The moisture content of the composition was brought to a moisture content of 20% by adding fuel oil brand M-100 (GOST 10585-99) (kinematic viscosity according to GOST 33-2000 is 98 cSt).

Then this emulsion in the amount of 6000 kg is sent to the working capacity and then fed with a flow rate of 6000 kg per hour into the vibro-cavitation homogenizer at a rotational speed of the rotor creating a centrifugal acceleration of 1600g and a gap between the rotor and the stator, which is 0.25 mm. The film thickness in which dispersion occurs in the specified gap will be 0.25 mm. At the same time, solid waste (coke), obtained by thermal methods of recycling rubber and tire waste during pyrolysis in the absence of oxygen at a temperature of 500-1000 ° С, is introduced into the pipeline supplying a mixture of hydrocarbons with water to the homogenizer (the composition of solid waste is given in table 1 ), in an amount up to 30% of the amount of the supplied liquid mixture. At the same time as solid waste, 0.1% magnesium oxide and 1.0% lower alcohols are fed from the amount of waste fed. The emulsification process is carried out in three passes. In the first pass, the coal fraction is introduced in an amount of -10% of the flow rate of the supplied liquid mixture, i.e. 600 kg / h In the second pass, the same amount is added, i.e. another 600 kg / h. A similar amount is served during the third pass of the mixture through a vibro-cavitation homogenizer. Thus, the total amount of coal fraction introduced into the liquid mixture in three passes is 1800 kg.

After four months of storage, the maximum droplet size does not exceed 12 μm, which confirms the receipt of a stable fuel emulsion containing a coal fraction.

EXAMPLE 4

As an oil-containing component, a sump emulsion based on fuel oil of the M-100 brand was used (GOST 10585-99, (kinematic viscosity according to GOST 33-2000 is 98 cSt, oil content 80% (mass.), Water 20% (mass.)) .

Then this emulsion in the amount of 6000 kg is sent to the working capacity and then fed with a flow rate of 6000 kg per hour into the vibro-cavitation homogenizer at a rotational speed of the rotor creating a centrifugal acceleration of 1600g and a gap between the rotor and the stator, which is 0.25 mm. The film thickness in which dispersion occurs in the specified gap will be 0.25 mm. At the same time, solid waste (coke), obtained by thermal methods of recycling rubber and tire waste during pyrolysis in the absence of oxygen at a temperature of 500-1000 ° С, is introduced into the pipeline supplying a mixture of hydrocarbons with water to the homogenizer (the composition of solid waste is given in table 1 ), in an amount up to 30% of the amount of the supplied liquid mixture. At the same time as solid waste, 2.0% of magnesium oxide and 1.0% of lower alcohols are fed from the amount of waste fed. The emulsification process is carried out in three passes. In the first pass, the coal fraction is introduced in an amount of -10% of the flow rate of the supplied liquid mixture, i.e. - 600 kg / h. In the second pass, the same amount is added, i.e. another 600 kg / h. A similar amount is served during the third pass of the mixture through a vibro-cavitation homogenizer. Thus, the total amount of coal fraction introduced into the liquid mixture in three passes is 1800 kg.

After four months of storage, the maximum droplet size does not exceed 10 microns, which makes it possible to obtain a stable fuel emulsion and use the resulting fuel as a boiler.

During preliminary tests of fuel compositions, the following results were obtained:

The equipment steadily functioned in all operating modes.

Switching the boiler system fuel system from the normal mode to the modes of operation on homogenized water-based emulsion fuel did not lead to the failure of the torch in the boiler.

Analysis of the concentration of components of harmful emissions in exhaust gases showed the following decrease in concentrations:

СО - by 33%;

NO - by 65%; NOx - by 70%.

The concentrations of the remaining components were below the sensitivity threshold of the gas analyzer.

Thus, from the above examples, it can be concluded that a stable aqueous emulsion fuel is obtained using a simpler technology compared to the prototype, which does not require additional grinding and separation of a specific coal fraction for feeding into a vibro-cavitation homogenizer. The resulting emulsion fuel has improved operational and environmental parameters.

Claims (1)

A method of processing oily waste based on oil sludge, fuel oil or a mixture thereof to produce water-based emulsion fuel, which includes heating the liquid oily waste, cleaning, followed by supplying a purified mixture of hydrocarbons with water to triple homogenization of the mixture in a vibration cavitation homogenizer with simultaneous supply of coal fraction from 15 to 30% of flow rate of the fluid to produce hydrated fuel with a relative centrifugal acceleration of the rotor of at least 1200 g and with a gap between the rotor and the stator n more than 0.25 mm, characterized in that at the same time, during the triple homogenization of the hydrocarbon mixture, a uniformly coal fraction is fed into the vibrocavitation homogenizer, which is solid waste obtained by thermal processing of rubber and tire waste during pyrolysis in the absence of oxygen at a temperature of 500-1000 ° C, with the simultaneous addition of a vibratory cavitation homogenizer to the solid waste during the first pass, 0.1-2% magnesium oxide and 0.1-1.0% lower alcohols from the total amount of solid waste.