A method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water

Abstract

A method for treating high-concentration, low-boiling-point organic waste liquid containing solid phase and water, firstly, using an organic solvent to prepare non-flammable and water mass percentage exceeding 25% and boiling point below 200°C organic waste liquid into an organic solution with more than 75% combustible components; firstly, using hot air to heat the organic steam delivery pipeline, premixing tube, and combustion nozzle, then sending the organic solvent into an evaporation tank, filtering and premixing with hot air, and then sending it into the combustion nozzle together, after ignition and combustion, the generated flue gas is mixed with the air sent into the reactor, heated to above 1000°C, and then the flue gas is cooled, dehydrated, and then adsorbed by activated carbon. The present invention can effectively treat high-concentration, low-boiling-point organic waste liquid containing solid phase and water, and ensure that the combustion process is stable, complete, safe and reliable.

Description

Technical Field

[0001] The invention relates to the field of waste liquid treatment, and in particular to a method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water. Background Art

[0002] Laboratory research is an important way to explore new discoveries, synthesize new materials, and solve new problems. In the process of laboratory research, a large amount of organic waste liquid is generated. Some organic solutions react directly with solids, or solid catalysts are used to catalyze the reaction of organic solutions. After these experiments, some solid phases will remain in the organic solvent, becoming organic waste liquid containing solid phases. In the process of doing experiments, it is inevitable to use water to wash various containers. After washing, these washing waters must also be treated as waste liquid. Therefore, the organic waste liquid generated in the laboratory will contain a certain amount of solid phases and water to a greater or lesser extent.

[0003] There are many types of organic waste liquids, and their properties vary greatly. Most organic waste liquids are flammable, such as alcohols, ethers, alkanes with more than 4 carbon atoms, and aromatic hydrocarbons; in addition, some organic waste liquids are not only non-flammable, but also have flame retardant effects, such as chloroform and carbon tetrachloride. Most organic solvents have low boiling points, such as methanol, with a boiling point of 64.7°C; ethanol, with a boiling point of 78°C; tetrahydrofuran, with a boiling point of 66°C; decahydronaphthalene, with a boiling point of 186.7°C; petroleum ether, with a boiling point of 30-80°C; dichloromethane, 39.75°C; pyridine, with a boiling point of 115.2°C; pyrrole, with a boiling point of 65°C; ethanedithiol, with a boiling point of 144-146°C; chloroform, with a boiling point of 62°C; chloroform, with a boiling point of 76.8°C.

[0004] In general, in the laboratory, due to the working characteristics of conducting research on various situations, the organic waste liquids produced are of various types and small quantities. Some organic waste liquids contain elements such as nitrogen, sulfur, and chlorine, and some organic waste liquids contain solid phases. Most organic waste liquids are volatile, flammable, and explosive, but some organic matter is non-flammable and even has a flame retardant effect. Some organic waste liquids are also toxic, and the organic waste liquids that need to be treated also contain a certain amount of water. Therefore, it is difficult to effectively and harmlessly treat these organic waste liquids.

[0005] Incineration is an effective method for treating organic waste liquid, but most of the incineration methods for organic waste liquid are industrial treatment methods. Since there are many types of laboratory organic waste liquids, their properties vary greatly, and their combustion characteristics also vary greatly, industrial treatment methods are not applicable to organic waste liquids with laboratory characteristics. At the same time, organic matter containing nitrogen, sulfur, and chlorine during the incineration process will produce pollutants, which will be discharged along with the flue gas after incineration; in addition, changes in the composition of organic waste liquid will cause incomplete combustion, and then generate pollutants such as dioxins and carbon soot.

[0006] In order to solve the problem of organic waste liquid generated by laboratory research, application number 201810347273.1X discloses a laboratory organic waste liquid harmless treatment technology. According to the principle of inductive coupling, the high-temperature flame generated by inductively coupled plasma is used to incinerate the atomized organic waste liquid, so that organic matter and oxygen react instantly to generate carbon dioxide and water, thereby achieving the purpose of harmless discharge. Application number 201810421716.2 discloses a laboratory organic waste liquid far-infrared treatment technology. According to the principle of far-infrared radiation, infrared lamps, quartz iodine lamps and other far-infrared radiators are used to generate high temperatures to incinerate atomized organic waste liquid, so that organic matter and oxygen react instantly to generate carbon dioxide and water, thereby achieving the purpose of harmless treatment. However, these two technologies do not consider the problem of solid phases in organic waste liquids. The solid phases contained in organic waste liquids can easily clog the atomizing nozzles; they also cannot effectively treat non-flammable organic components. Summary of the invention

[0007] In order to solve the defects of the existing organic waste liquid treatment technology, the purpose of the present invention is to provide a method for treating high-concentration low-boiling point organic waste liquid containing solid matter and water.

[0008] To achieve the above object, the present invention adopts the following technical scheme: a method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water, comprising the following steps:

[0009] (1) Organic waste liquids with boiling points below 200°C generated in laboratory research are divided into combustible organic waste liquids and non-combustible organic waste liquids through chemical analysis;

[0010] (2) Further classify the combustible organic waste liquid into two parts: the mass percentage of water in the organic waste liquid is higher than 25% and lower than 25%;

[0011] (3) Mixing non-combustible organic waste liquid with an organic solvent that has good combustion characteristics, is cheap, and has strong miscibility to prepare a solution with a mass percentage of combustible components exceeding 75%;

[0012] (4) Mixing combustible organic waste liquid with a water mass percentage higher than 25% with an organic solvent having good combustion characteristics, low price and strong miscibility to prepare a solution with a combustible component mass percentage higher than 75%;

[0013] (5) Heating the air required for combustion and using hot air to heat the organic steam delivery pipeline, premixing pipe, and combustion nozzle, so that the organic steam delivery pipeline, premixing pipe, and combustion nozzle exceed 200°C;

[0014] (6) A solution containing a combustible component with a mass percentage higher than 75% is fed into an evaporator at a rate of 5-50 ml / min to evaporate the organic solvent. The temperature of the evaporator is maintained at above 200°C. The organic waste liquid is continuously fed into the evaporator until the pressure in the evaporator exceeds 0.3 MPa. The evaporated organic waste liquid vapor is filtered and pre-mixed with hot air. The combustible gas pre-mixed with the organic solution vapor and the hot air is fed into the combustion nozzle;

[0015] (7) Ignite the combustible gas premixed with organic solution vapor and hot air through an igniter;

[0016] (8) Excess air is introduced into the combustion reactor, and the combustion flue gas is further heated to above 1000°C by electric heating, so that the combustible components in the flue gas can be burned more completely;

[0017] (9) Use a heat exchanger to cool the flue gas generated after combustion to below 100°C;

[0018] (10) Eliminate moisture from flue gas;

[0019] (11) Use activated carbon to absorb pollutants such as NOx, SOx, HCl, dioxins, and carbon black in flue gas.

[0020] Preferably, in the method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water, the organic solvent with good combustion characteristics, low price and strong mutual solubility is anhydrous methanol or anhydrous ethanol.

[0021] Preferably, in the method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water, the temperature of the evaporation tank is maintained at 400-600°C.

[0022] Preferably, the method for treating high-concentration, low-boiling-point organic waste liquid containing solid matter and water heats the entire organic steam delivery pipeline and combustion nozzle by hot air, so that the temperature of the delivery pipeline, premixing pipe and combustion nozzle is above 400°C.

[0023] Preferably, in the method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water, after the pressure in the evaporation tank exceeds 0.5 MPa, the organic solution vapor is sent to mix with the hot air.

[0024] Preferably, in the method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water, the flue gas generated after burning the organic waste liquid is cooled to below 60°C.

[0025] Preferably, in the method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water, the evaporator, organic steam delivery pipeline, combustion nozzle, combustion reactor, heat exchanger, etc. are all made of stainless steel.

[0026] Compared with the prior art, the present invention has the following advantages.

[0027] 1. By mixing non-combustible organic waste liquid and organic waste liquid with high water content with anhydrous methanol or anhydrous ethanol, an organic solution with more than 75% combustible components can be prepared. This can decompose the non-combustible components under the high temperature conditions generated by combustion, and can also make the organic waste liquid with high water content more stable during combustion.

[0028] 2. After evaporating and filtering the organic waste liquid containing solid matter and water, maintain a high temperature environment to transport and burn the organic waste liquid vapor without arranging atomizing nozzles, which can prevent the solid phase from clogging the transportation pipeline and prevent the components of the organic waste liquid from condensing during the transportation process.

[0029] 3. Send the organic waste liquid into the evaporation tank, and then send gas into the evaporation tank for combustion after it reaches a certain pressure. This can effectively and stably control the steam flow of the organic waste liquid, which is conducive to the stability of the combustion flame process.

[0030] 4. The combustion-supporting air is heated before being sent into the burner, which effectively prevents the flameout during the combustion of organic waste liquid vapor.

[0031] 5. The flue gas produced by combustion is further mixed with air and heated to 1000°C, which helps to make the combustible components in the flue gas burn more completely. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The process flow chart of the present invention is a method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water.

[0033] Embodiment 1

[0034] In the hot melt extraction test of coal, organic solvents such as methanol, acetone, petroleum ether, and chloroform are often used for extraction. After the test, the mass percentage of coal powder and coal ash in the generated methanol waste liquid was 1.26%, and the mass percentage of water was 29%; the mass percentage of coal powder and coal ash in the acetone waste liquid was 0.58%, and the mass percentage of water was 13%; the mass percentage of coal powder and coal ash in the petroleum ether waste liquid was 1.35%, and the mass percentage of water was 22%; the mass percentage of coal powder and coal ash in the chloroform waste liquid was 0.62%, and the mass percentage of water was 6%.

[0035] First, the boiling points of the above four organic waste liquids are all less than 200°C. The four organic waste liquids are classified. The water content in acetone waste liquid and petroleum ether waste liquid is 13% and 22%, respectively, and no treatment is required; the mass percentage of water in methanol waste liquid is 29%, and the mass percentage of solid phase is 1.26%. By adding anhydrous methanol to the waste liquid at a mass ratio of 5%, the mass fraction of the combustible part in the methanol waste liquid exceeds 75%; chloroform is non-flammable, and the water contained in it is also non-flammable. Therefore, more than three times the mass of anhydrous methanol is mixed into the chloroform waste liquid to make the mass fraction of anhydrous methanol exceed 75%.

[0036] The premixed air required for combustion is heated to 400°C, and the hot air is used to heat the organic steam delivery pipeline, premixing pipe, combustion nozzle, etc., so that the temperature of the organic steam delivery pipeline, premixing pipe, combustion nozzle, etc. reaches above 400°C.

[0037] The prepared solutions with a mass fraction of combustible components exceeding 75% are treated separately. During the treatment, the solution is sent to the evaporator at a rate of 10 ml / min. The temperature of the evaporator is maintained at 400 ° C. A filter assembly is arranged at the outlet of the evaporator. When the pressure in the evaporator reaches 0.5 MPa, the organic vapor outlet valve is opened to allow the organic vapor to be sent to the premixing pipe after filtering, and then sent to the combustion nozzle after premixing with the heated air.

[0038] The combustible gas premixed with organic solution vapor and hot air is ignited by an igniter.

[0039] Excess air is introduced into the combustion reactor, and the combustion flue gas is further heated to above 1000°C using electric heating, so that the combustible components in the flue gas can be burned more completely.

[0040] A heat exchanger is used to cool the flue gas produced after combustion to below 100°C.

[0041] Eliminate moisture from flue gas.

[0042] Activated carbon is used to adsorb pollutants such as NOx, SOx, HCl, dioxins, and carbon black in flue gas.

[0043] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0044] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water, characterized in that: The following steps are involved: (1) The organic waste liquid generated by laboratory research is divided into two categories: combustible organic waste liquid and non-combustible organic waste liquid; (2) The combustible organic waste liquid is further classified by analysis into two parts: the mass percentage of water in the organic waste liquid is higher than 25% and the mass percentage of water in the organic waste liquid is lower than 25%; (3) mixing the non-combustible organic waste liquid with an organic solvent to prepare a solution having a combustible component mass percentage greater than 75%; (4) Mixing a combustible organic waste liquid containing more than 25% water by mass with an organic solvent to prepare a solution containing more than 75% combustible components by mass; (5) heating the air required for combustion, and using the hot air to heat the organic steam delivery pipeline, premixing pipe, and combustion nozzle, so that the organic steam delivery pipeline, premixing pipe, and combustion nozzle exceed 200°C; (6) A solution containing more than 75% by mass of combustible components is fed into an evaporator to evaporate the organic solvent. The temperature of the evaporator is maintained at above 200°C. Organic waste liquid is continuously fed into the evaporator until the pressure in the evaporator exceeds 0.3 MPa. The evaporated organic waste liquid vapor is filtered and pre-mixed with hot air. The combustible gas pre-mixed with the organic solution vapor and the hot air is fed into the combustion nozzle; (7) Ignite the combustible gas premixed with organic solution vapor and hot air through an igniter; (8) Excess air is introduced into the combustion reactor, and the combustion flue gas is further heated by electric heating to make the combustible components in the flue gas burn more completely; (9) Use a heat exchanger to cool the flue gas generated after combustion to below 100°C; (10) Eliminate moisture from flue gas; (11) Use activated carbon to adsorb NOx, SOx, HCl, dioxins and carbon black in flue gas.

2. The method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water according to claim 1, characterized in that The organic solvent is anhydrous methanol or anhydrous ethanol.

3. The method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water according to claim 1, characterized in that The temperature of the evaporation tank is maintained at 400-600°C.

4. The method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water according to claim 1, characterized in that The temperature of the organic steam delivery pipeline, premixing pipe and combustion nozzle is above 400°C.

5. The method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water according to claim 1, characterized in that Air is introduced into the combustion reactor, mixed with the flue gas generated by the combustion, and then heated to above 1000°C.

6. The method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water according to claim 1, characterized in that The heat exchanger cools the flue gas generated after combustion to below 60°C.

7. The method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water according to claim 1, characterized in that After the pressure in the evaporation tank exceeds 0.5 MPa, the organic solution vapor is sent to mix with the hot air.

8. The method for treating high-concentration low-boiling-point organic waste liquid containing solid matter and water according to claim 1, characterized in that The evaporation tank, organic steam delivery pipeline, combustion nozzle, combustion reactor, heat exchanger, etc. are all made of stainless steel.

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