阅读说明：本技术 一种适用于热解油的超声波雾化燃烧系统及方法 (Ultrasonic atomization combustion system and method suitable for pyrolysis oil ) 是由 姚宗路 郝晓文 赵立欣 贾吉秀 霍丽丽 赵亚男 于 2020-06-09 设计创作，主要内容包括：本发明公开了一种适用于热解油的超声波雾化燃烧系统及方法,属于涉及生物质热解油领域,以解决目前热解油燃烧系统在运行中容易出现的燃烧不完全而冒黑烟、污染物排放量高等问题。该系统包括超声波乳化罐、伴热油路、燃烧室、超声波发生器、超声波雾化喷嘴,所述超声波乳化罐一侧为进油口,另一侧接有伴热油路,超声波乳化罐的下方设有加热器；所述超声波雾化喷嘴包括雾化空气外腔、油腔、雾化空气内腔、超声波油气混合振荡腔。本发明利用超声波乳化罐在热解油雾化之前对热解油进行超声波乳化处理,改善了热解油的性质,降低热解油粘度。同时,伴热油路和特殊的雾化喷嘴结构都适用于粘稠的热解油。(The invention discloses an ultrasonic atomization combustion system and method suitable for pyrolysis oil, belongs to the field of biomass pyrolysis oil, and aims to solve the problems that incomplete combustion, black smoke emission, high pollutant discharge amount and the like easily occur in the operation of the conventional pyrolysis oil combustion system. The system comprises an ultrasonic emulsification tank, a heat tracing oil path, a combustion chamber, an ultrasonic generator and an ultrasonic atomization nozzle, wherein one side of the ultrasonic emulsification tank is provided with an oil inlet, the other side of the ultrasonic emulsification tank is connected with the heat tracing oil path, and a heater is arranged below the ultrasonic emulsification tank; the ultrasonic atomizing nozzle comprises an atomizing air outer cavity, an oil cavity, an atomizing air inner cavity and an ultrasonic oil-gas mixing oscillation cavity. According to the invention, the ultrasonic emulsification tank is used for carrying out ultrasonic emulsification treatment on the pyrolysis oil before the pyrolysis oil is atomized, so that the property of the pyrolysis oil is improved, and the viscosity of the pyrolysis oil is reduced. Meanwhile, the heat tracing oil circuit and the special atomizing nozzle structure are both suitable for viscous pyrolysis oil.)

1. An ultrasonic atomization combustion system suitable for pyrolysis oil comprises an ultrasonic emulsification tank (1), a heat tracing oil way (2), a combustion chamber (6), an ultrasonic generator (7) and an ultrasonic atomization nozzle (5), wherein the tail end of the heat tracing oil way (2) is connected with the ultrasonic atomization nozzle (5), the outlet end of the ultrasonic atomization nozzle (5) is inserted into the combustion chamber (6), and the ultrasonic atomization nozzle (5) is also connected with the ultrasonic generator (7); the method is characterized in that: an oil inlet is formed in one side of the ultrasonic emulsification tank (1), a heat tracing oil circuit (2) is connected to the other side of the ultrasonic emulsification tank, and a heater (11) is arranged below the ultrasonic emulsification tank (1); ultrasonic atomization nozzle (5) is including atomizing air exocoel (52), oil pocket (53), atomizing air inner chamber (55), ultrasonic wave oil gas mixture oscillation chamber (58), and outmost atomizing air exocoel (52) that is, the intermediate level is oil pocket (53), and the inlayer is atomizing air inner chamber (55), and the front end of atomizing air exocoel (52) is equipped with atomizing air through-hole (56), evenly arranges whirl shower nozzle (51) around the throat end inclined plane of oil pocket (53), and the outer wall of ultrasonic wave oil gas mixture oscillation chamber (58) is equipped with ultrasonic oscillator (57).

2. The ultrasonic atomizing combustion system for pyrolysis oil of claim 1, wherein: 8-12 swirl nozzles (51) are provided, and swirl grooves (50) are arranged on two sides of each nozzle.

3. An ultrasonic atomizing combustion system suitable for pyrolysis oil according to claim 1 or 2, wherein: the heat tracing oil circuits (2) are two, basket filters (3) are arranged on the heat tracing oil circuits, and oil pressure pumps (4) are further arranged on the heat tracing oil circuits.

4. The ultrasonic atomizing combustion system for pyrolysis oil of claim 3, wherein: the inside of the heat tracing oil circuit (2) is a pipeline, and the outside is provided with a heating insulation layer (21).

5. The method for atomizing combustion by using the ultrasonic atomizing combustion system for pyrolysis oil according to claim 1, characterized by comprising the steps of:

A. selecting 45-55% by volume of biomass pyrolysis oil, 10-20% by volume of auxiliary emulsion methanol and 35-45% by volume of diesel oil, uniformly mixing, adding into an ultrasonic emulsification tank, setting the heating temperature of a heater to be 80-100 ℃, and connecting an oil circuit; emulsifying the mixed solution into pyrolysis oil-diesel oil emulsion by ultrasonic emulsification;

B. an air compressor (10) and an air storage tank (9) are opened, and air is used as an atomizing agent and is filled into the ultrasonic atomizing nozzle (5) through a heat tracing air passage (8); opening an oil way and an oil pressure pump, and adjusting the atomization pressure of the biomass pyrolysis oil; turning on a switch of an ultrasonic generator connected with an ultrasonic oscillator (57) in the nozzle, and breaking the pyrolysis oil into liquid drop particles smaller than 10um after the pyrolysis oil enters the three-stage ultrasonic atomization nozzle; the first atomization is generated between an atomizing air outer cavity (52) and an oil cavity (53), pyrolysis tar is sprayed out by a cyclone spray head (51) which is annularly arranged after passing through the oil cavity (53), the second atomization is generated between an atomizing air inner cavity (55) and a nozzle shell (54), high-pressure air is mixed with liquid drops which are subjected to the first atomization after passing through the atomizing air inner cavity (55) to carry out secondary atomization on the liquid drops, and the oil drops which are subjected to the secondary atomization enter an ultrasonic oil-gas mixing oscillation cavity (58), are extruded and guided by the ultrasonic oil-gas mixing oscillation cavity (58) and an ultrasonic oscillator (57) under the action of the ultrasonic oscillator (57) to carry out third atomization, and are sprayed out by a main spray head (59);

C. spraying the liquid droplet particles into a combustion chamber of a combustor, and turning on an igniter for ignition and combustion; and (3) starting a high-pressure fan (66) and a tube heat exchanger (63) to exchange heat with the combustor and the flue gas, wherein the high-pressure fan and the temperature signal adopt a closed-loop control principle to ensure that the temperature of the flue gas outlet is below 200 ℃.

6. The method of claim 5, wherein: the mixed oil added into the ultrasonic emulsification tank comprises 55% of biomass pyrolysis oil, 10% of auxiliary emulsion agent methanol and 35% of diesel oil.

Technical Field

The invention belongs to the field of biomass pyrolysis oil, and particularly relates to an ultrasonic atomization combustion system and method suitable for pyrolysis oil.

Background

The biomass pyrolysis oil has higher calorific value and oxygen content, and is one of important objects of renewable energy technology research. However, the biomass pyrolysis oil has the problems of high viscosity, more impurities and the like, and resource utilization of the biomass pyrolysis oil is hindered. At present, the quality improvement and modification treatment methods of biomass tar mainly comprise an emulsification method, a chemical method and the like, wherein the chemical method has the problems of complex process, high modification cost and the like.

The ultrasonic emulsification method is an oil product modification method with simple process and low cost. Under the action of ultrasonic waves, the two immiscible liquids and the surfactant destroy the original intermolecular surface tension of the solution due to the ultrasonic cavitation effect, so that the two liquids are mutually dissolved to form stable emulsion, the viscosity of the pyrolysis oil can be reduced, and the combustion performance and the energy grade of the biological tar are improved.

For high-viscosity liquid fuels such as biomass pyrolysis oil, the nozzle technology is the core of the atomization combustion technology, the performance of the nozzle directly influences the atomization effect and the service life of the nozzle, and the normal and stable operation of the combustion process is related. Due to the characteristics of high viscosity, high density, high surface tension, difficult atomization and the like of the biomass pyrolysis oil, few nozzles which can be applied to the biomass pyrolysis oil are available at present.

Disclosure of Invention

The invention aims to provide an ultrasonic atomizing combustion system suitable for pyrolysis oil, and aims to solve the problems that the conventional pyrolysis oil combustion system is easy to burn incompletely, black smoke is emitted, the pollutant discharge amount is high and the like in the operation process.

The technical scheme of the invention is as follows: an ultrasonic atomization combustion system suitable for pyrolysis oil comprises an ultrasonic emulsification tank, a heat tracing oil way, a combustion chamber, an ultrasonic generator and an ultrasonic atomization nozzle, wherein the tail end of the heat tracing oil way is connected with the ultrasonic atomization nozzle, the outlet end of the ultrasonic atomization nozzle is inserted into the combustion chamber, and the ultrasonic atomization nozzle is also connected with the ultrasonic generator; an oil inlet is formed in one side of the ultrasonic emulsification tank, a heat tracing oil way is connected to the other side of the ultrasonic emulsification tank, and a heater is arranged below the ultrasonic emulsification tank; the ultrasonic atomizing nozzle comprises an atomizing air outer cavity, an oil cavity, an atomizing air inner cavity and an ultrasonic oil-gas mixing oscillation cavity, the outermost atomizing air outer cavity is provided, the middle layer is the oil cavity, the innermost atomizing air inner cavity is provided, the front end of the atomizing air outer cavity is provided with an atomizing air through hole, the periphery of the inclined plane of the necking end of the oil cavity is uniformly provided with a cyclone spray head, and the outer wall of the ultrasonic oil-gas mixing oscillation cavity is provided with an ultrasonic oscillator.

Furthermore, 8-12 swirl nozzles are provided, and swirl grooves are arranged on two sides of each nozzle.

Furthermore, the heat tracing oil paths are two, basket filters are arranged on the heat tracing oil paths, and an oil pressure pump is further arranged on the heat tracing oil paths.

Furthermore, the inside of the heat tracing oil circuit is a pipeline, and the outside of the heat tracing oil circuit is provided with a heating insulation layer.

The method for carrying out atomized combustion by using the ultrasonic atomized combustion system suitable for the pyrolysis oil is characterized by comprising the following steps of:

A. selecting 45-55% by volume of biomass pyrolysis oil, 10-20% by volume of auxiliary emulsion methanol and 35-45% by volume of diesel oil, uniformly mixing, adding into an ultrasonic emulsification tank, setting the heating temperature of a heater to be 80-100 ℃, and connecting an oil circuit; emulsifying the mixed solution into pyrolysis oil-diesel oil emulsion by ultrasonic emulsification;

B. opening an air compressor and an air storage tank, and filling air serving as an atomizing agent into the ultrasonic atomizing nozzle through a heat tracing air path; opening an oil way and an oil pressure pump, and adjusting the atomization pressure of the biomass pyrolysis oil; turning on a switch of an ultrasonic generator connected with an ultrasonic oscillator in the nozzle, and breaking the pyrolysis oil into liquid drop particles smaller than 10um after the pyrolysis oil enters the three-stage ultrasonic atomization nozzle;

the first atomization is carried out between the atomizing air outer cavity and the oil cavity, the pyrolysis tar is sprayed out by the annular swirl nozzle after passing through the oil cavity,

the second atomization is carried out between the atomizing air inner cavity and the nozzle shell, high-pressure air passes through the atomizing air inner cavity and then is mixed with the liquid drops atomized for the first time, the liquid drops are atomized for the second time, the oil mist after the second atomization enters the ultrasonic oil-gas mixing oscillation cavity,

under the action of the ultrasonic oscillator, the mixture is extruded and guided by the ultrasonic oil-gas mixing oscillation cavity and the ultrasonic oscillator to carry out third atomization, and then the mixture is sprayed out through the main spray head;

C. spraying the liquid droplet particles into a combustion chamber of a combustor, and turning on an igniter for ignition and combustion; and (3) starting a high-pressure fan and a tube heat exchanger, exchanging heat between the combustor and the flue gas, and ensuring the temperature of the flue gas outlet to be below 200 ℃ by adopting a closed-loop control principle of the high-pressure fan and a temperature signal.

Further, the mixed oil added into the ultrasonic emulsification tank comprises 55% by volume of biomass pyrolysis oil, 10% by volume of co-emulsion agent methanol and 35% by volume of diesel oil.

The mechanism of the invention is as follows: pyrolysis oil ultrasonic atomization combustion system reduces the viscosity of pyrolysis oil through ultrasonic emulsification with pyrolysis oil, improves the atomizing property of pyrolysis oil, utilizes the tertiary atomizing of ultrasonic wave formula to improve the atomization effect of pyrolysis oil emulsifier greatly, atomizes pyrolysis oil emulsifier for tiny liquid drop granule, and abundant burning and flue gas heat transfer can effectively realize high-efficient burning, low polluting emission in the combustion chamber.

The invention has the following characteristics:

(1) the ultrasonic emulsification tank is utilized to carry out ultrasonic emulsification treatment on the pyrolysis oil before the pyrolysis oil is atomized, so that the property of the pyrolysis oil is improved, and the viscosity of the pyrolysis oil is reduced. Meanwhile, the heat tracing oil circuit and the special atomizing nozzle structure are both suitable for viscous pyrolysis oil.

(2) The ultrasonic atomizing nozzle has a special three-level atomizing structure, and the atomizing mode combining internal mixing type air atomization and ultrasonic atomization makes pyrolysis oil atomized completely, atomized particles small and atomized uniformly. The pyrolysis oil burner adopting the ultrasonic atomizing nozzle has the advantages of easy ignition, uniform fire discharge, complete combustion and less black smoke.

(3) The ultrasonic wave ultrasonic atomization combustion system can continuously carry out three processes of ultrasonic emulsification, atomization and combustion of the pyrolysis oil, so that the continuity and integration of the modification combustion process of the pyrolysis oil are realized, and the pollution caused in the pyrolysis oil treatment and transportation process is reduced.

Drawings

FIG. 1 is a schematic diagram of an ultrasonic atomizing combustion system suitable for pyrolysis oil;

FIG. 2 is a schematic view of an ultrasonic atomizing nozzle for use in an ultrasonic atomizing combustion system for pyrolysis oil;

fig. 3 is a side view of fig. 2.

The reference numerals have the following meanings: 1-ultrasonic emulsification tank; 2-heat tracing oil way; 3-basket filters; 4-oil hydraulic pump; 5-ultrasonic atomizing nozzle; 6-a combustion chamber; 7-an ultrasonic generator; 8-heat tracing gas circuit; 9-a gas storage tank; 10, an air compressor; 11-a heater; 12-an ultrasonic transducer; 21-heating the heat insulation layer; 50-a swirl groove; 51-swirl nozzles; 52-atomizing air outer cavity; 53-oil chamber; 54-a nozzle housing; 55-atomizing air cavity; 56-atomizing air through holes; 57-an ultrasonic oscillator; 58-ultrasonic wave oil gas mixing oscillation cavity; 59-Total showerhead; 61-a combustion chamber; 62-heat exchange air outlet device; 63-shell-and-tube heat exchangers; 64-a flue gas outlet; 65-flame viewing aperture; 66-high pressure fan; 67-blower.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

As shown in figure 1, the ultrasonic atomizing combustion system suitable for pyrolysis oil comprises an ultrasonic emulsification tank 1, a heat tracing oil circuit 2, a combustion chamber 6, an ultrasonic generator 7 and an ultrasonic atomizing nozzle 5, wherein the tail end of the heat tracing oil circuit 2 is connected with the ultrasonic atomizing nozzle 5, the outlet end of the ultrasonic atomizing nozzle 5 is inserted into the combustion chamber 6, and the ultrasonic atomizing nozzle 5 is further connected with the ultrasonic generator 7. The left side of the ultrasonic emulsification tank 1 is an oil inlet, the right side of the ultrasonic emulsification tank is connected with a heat tracing oil path 2, and the heater 11 is arranged below the ultrasonic emulsification tank 1 and provides a higher temperature environment for an emulsifier in the emulsification tank. The ultrasonic generator 7 is connected with the ultrasonic emulsification tank 1 through an ultrasonic transducer 12. The inside of the heat tracing oil path is a pipeline, and the outside is attached with a heating insulation layer 21, so that the higher temperature of the emulsifier can be kept, the fluidity of the emulsifier is improved, and the condensation blockage is avoided. And the basket filters 3 are arranged on the two branches of the heat tracing oil circuit to filter the impurities of the emulsifier and prevent the nozzle from being blocked. An oil pressure pump 4 is also arranged on the heat tracing oil circuit to control the atomizing pressure of the emulsifier. The tail end of the heat tracing oil path 2 is connected with an ultrasonic atomizing nozzle 5.

The ultrasonic atomizing nozzle 5 comprises an atomizing air outer cavity 52, an oil cavity 53, an atomizing air inner cavity 55 and an ultrasonic oil-gas mixing oscillation cavity 58, the outermost layer is the atomizing air outer cavity 52, the middle layer is the oil cavity 53, the innermost layer is the atomizing air inner cavity 55, an atomizing air through hole 56 is formed in the front end of the atomizing air outer cavity 52, a swirl spray head 51 is uniformly arranged on the periphery of a reducing end inclined plane of the oil cavity 53, and an ultrasonic oscillator 57 is arranged on the outer wall of the ultrasonic oil-gas mixing oscillation cavity 58.

The outlet of the ultrasonic atomizing nozzle 5 is inserted into the combustion chamber 6. An igniter is provided below the ultrasonic atomizing nozzle 5 to ignite the oil mist, so that the oil mist is sufficiently combusted in the combustion chamber 61 in the combustion chamber. The top of the combustion chamber 6 is provided with a heat exchange air outlet device 62, the inside of the combustion chamber is provided with a tube heat exchanger 63, the side end of the combustion chamber 6 is provided with a flue gas outlet 64, hot flue gas flows through the inner side of the tube heat exchanger 63, and cold air flows through the outer side of the tube heat exchanger 63, so that the high-efficiency heat exchange of the flue gas is realized. The combustion chamber is also provided with a flame observation hole 65 for observing the flame length and checking the combustion state, and a high pressure fan 66 and a blower 67 are arranged below the combustion chamber, so that the contact amount of oxygen and atomized liquid drops can be increased, the atomized liquid drops can be more fully combusted, and the heat exchange of flue gas can be accelerated.

Ultrasonic atomizing nozzle principle: the integral structure of the ultrasonic atomization device is divided into an atomizing air outer cavity 52, an oil cavity 53, an atomizing air inner cavity 55 and an ultrasonic oil-gas mixing oscillation cavity 58 by adopting a mode of combining inner mixing type air atomization and ultrasonic oscillation atomization, the outermost layer is the atomizing air outer cavity 52, the middle layer is the oil cavity 53, the innermost layer is the atomizing air inner cavity 55 when viewed in the radial direction, and 8-12 swirl nozzles 51 are uniformly arranged around the inclined plane of the reducing end of the oil cavity 53. The first atomization is generated between an atomizing air outer cavity 52 and an oil cavity 53, pyrolysis tar is sprayed out by a cyclone spray head 51 which is annularly arranged after passing through the oil cavity 53, the two sides of each spray head are provided with a cyclone groove 50, high-pressure air of the atomizing air outer cavity collides with pyrolysis tar liquid drops sprayed out by the cyclone spray head 51 after passing through the cyclone grooves 50 to form primary atomization, secondary atomization is generated between an atomizing air inner cavity 55 and a nozzle shell 54, high-pressure air is mixed with the liquid drops which are primarily atomized after passing through an atomizing air inner cavity 55 to carry out secondary atomization on the liquid drops, oil mist after secondary atomization enters an ultrasonic oil-gas mixing oscillation cavity 58, is extruded and guided by the mixing cavity 58 and an ultrasonic oscillator 57 under the action of the ultrasonic oscillator 57 to carry out tertiary atomization, is further atomized into smaller particles, and is sprayed out by a main spray head 59, and the structural design forces the pyrolysis tar liquid drops to undergo a tertiary atomization process, achieving better atomization effect.