System and method for treating BDO organic waste liquid

Abstract

The invention discloses a system and method for treating BDO organic waste liquid, and the main process is as follows: decomposing the BDO organic waste liquid to obtain gas micromolecules, adding a certain amount of oxygen into the gas micromolecules, carrying out gasification reaction to obtain a product, then separating the product, and finally electrolyzing oxygen by using a water electrolysis hydrogen production system to supply the oxygen to the gasification reaction. And selling the hydrogen. According to the device and the method for extracting the synthesis gas, energy consumption is lower, impurities can be better separated, large-scale production can be achieved, heat is transferred to low-temperature substances by high-temperature substances in the process, and heat waste is greatly reduced.

Description

Technical Field

[0001] The invention relates to the technical field of waste liquid recovery and treatment, and in particular to a system and method for treating BDO organic waste liquid, wherein the BDO organic waste liquid is treated by a gasification method in series with a water electrolysis method for producing hydrogen to achieve a maximum recovery rate. Background Art

[0002] BDO, also known as 1,4-butanediol, is an important organic chemical and fine chemical raw material, which can produce a variety of derivatives such as tetrahydrofuran (THF), polytetrahydrofuran (PTMEG), γ-butyrolactone (GBL), etc. BDO and its derivatives can be widely used in polybutylene terephthalate (PBT), plastics, spandex, polyurethane, pharmaceuticals, cosmetics and other fields.

[0003] The Reppe process for producing BDO generates a large amount of waste liquid containing BDO and sodium salt, which is generally incinerated at present, resulting in low utilization rate and economic benefits and causing environmental pollution. Summary of the invention

[0004] In order to overcome the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a system and method for treating BDO organic waste liquid. The present invention is a system and method for treating BDO organic waste liquid with lower energy consumption, more synthesis gas production, and large-scale production. In the process, water and oxygen are recovered, and the emission of pollutants is greatly reduced.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A system for treating BDO organic waste liquid, comprising a BDO organic waste liquid fixed bed gasifier 1, wherein the BDO organic waste liquid is introduced into the inlet of the BDO organic waste liquid fixed bed gasifier 1, the outlet of the BDO organic waste liquid fixed bed gasifier 1 is connected to the inlet of the BDO organic waste liquid fluidized flow gasifier 2, the outlet of the BDO organic waste liquid fluidized flow gasifier 2 is connected to the inlet of a product heat exchanger 3, the outlet of the product heat exchanger 3 is connected to the inlet of a heat exchanger 4, the outlet of the heat exchanger 4 is connected to the inlet of a gas-liquid-solid separation tank 5, waste is discharged from the top of the gas-liquid-solid separation tank 5, water separated from the middle of the gas-liquid-solid separation tank 5 is connected to a liquid mixer 8, and ash and carbonic acid are discharged from the bottom outlet of the gas-liquid-solid separation tank 5. Sodium, the top synthesis gas outlet of the gas-liquid-solid separation tank 5 is connected to the cold side inlet of the gas heat exchanger 6, the hot side outlet of the gas heat exchanger 6 is connected to the gas compressor 7, the compressed gas is packaged and sent to the user, the liquid mixer 8 mixes the water separated from the gas-liquid-solid separation tank 5 with fresh water and then connects it to the inlet of the electrolytic water hydrogen production system 9, the outlet of the electrolytic water hydrogen production system 9 is connected to the gas-liquid separation tank 10, the oxygen outlet at the top of the gas-liquid separation tank 10 is connected to the inlet of the BDO organic waste liquid fluidized flow gasification furnace 2, the liquid water outlet at the bottom of the electrolytic water hydrogen production system 9 is connected to the electrolytic water hydrogen production system 9, and the hydrogen produced by the electrolytic water hydrogen production is exported at the top of the gas-liquid separation tank 10.

[0007] The separation of synthesis gas and waste gas at the top of the gas-liquid-solid separation tank 5 and the separation of oxygen and hydrogen at the top of the gas-liquid separation tank 10 are achieved by setting different gas permeation membranes in the gas pipelines in the gas-liquid-solid separation tank 5 and the gas-liquid separation tank 10, and the separation of different gases is achieved according to the different permeation rates of different gases.

[0008] The BDO organic waste liquid fixed bed gasifier 1 is provided with a gasifier nozzle.

[0009] A quenching tank and an ash hopper are provided at the bottom of the gas-liquid-solid separation tank 5 .

[0010] The heat of the BDO organic waste liquid entrained flow gasification furnace 2 is transferred to the water electrolysis hydrogen production system 9.

[0011] The heat of the product heat exchanger 3 is transferred to the gas heat exchanger 6 .

[0012] The working method of the system for treating BDO organic waste liquid comprises the following steps:

[0013] Step 1: Treating BDO organic waste liquid by gasification: BDO organic waste liquid is introduced into BDO organic waste liquid fixed bed gasifier 1 to decompose BDO organic waste liquid macromolecules into BDO organic waste liquid small molecules, and the BDO organic waste liquid small molecules then enter BDO organic waste liquid fluidized flow gasifier 2 for gasification reaction, and are cooled by product heat exchanger 3 and heat exchanger 4, and separated by gas-liquid-solid separation tank 5. The top is the synthesis gas and part of methane and carbon dioxide wastes produced by the gasification reaction, and part of methane and carbon dioxide wastes are discharged. The synthesis gas produced at the top is heated by gas heat exchanger 6 and then enters compressor 7 for compression and then sent to users. The bottom of gas-liquid-solid separation tank 5 is the ash produced and sodium carbonate solid, which are packaged and sold;

[0014] Step 2: Electrolysis of water to produce hydrogen:

[0015] The water produced by the BDO organic waste liquid fluidized flow gasifier 2 is separated in the gas-liquid-solid separation tank 5 and enters the liquid mixer 8 together with fresh water, and then enters the water electrolysis hydrogen production system 9. The gas coming out of the water electrolysis hydrogen production system 9 enters the gas-liquid separation tank 10. The oxygen separated at the top of the gas-liquid separation tank 10 enters the BDO organic waste liquid fluidized flow gasifier 2 as a gasifying agent for gasification reaction. The hydrogen separated at the top of the gas-liquid separation tank 10 is sold. The liquid water that has not reacted completely in the water electrolysis hydrogen production system 9 is separated by the gas-liquid separation tank 10 and then returns to the water electrolysis hydrogen production system 9 to continue the reaction.

[0016] In step 1, the gasification reaction is carried out under normal pressure at a temperature of 600-1000°C, and the temperature of the synthesis gas after heat exchange in the gas heat exchanger 6 is 300°C.

[0017] In step 2, the efficiency of converting water in the water electrolysis hydrogen production system 9 into hydrogen and oxygen is more than 68% and is related to the water feed. The water separated by the gas-liquid-solid separation tank 10 is used as the raw material for water electrolysis hydrogen production. If the generated oxygen is not enough to supply the entrained flow gasifier 2 for gasification reaction, an appropriate amount of fresh water is added to the liquid mixer 8 according to the oxygen consumption, or an appropriate amount of oxygen is directly introduced into the BDO organic waste liquid entrained flow gasifier 2.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] 1. The purpose of the present invention is to provide a harmless, reduced and resource-based BDO organic waste liquid treatment system and method, so that the water electrolysis hydrogen production system is combined with the gasification method, so as to increase the recycling of resources, reduce economic costs and increase economic benefits.

[0020] 2. Compared with the existing incineration method, the method of treating BDO organic waste liquid by gasification in the present invention greatly reduces pollutant emissions, and significantly improves environmental protection level and economic efficiency.

[0021] 3. The present invention combines the water electrolysis hydrogen production system with the gasification method to treat BDO organic waste liquid, thereby achieving maximum utilization of heat, increasing resource recycling, and saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the system of the present invention.

[0023] Figure 2 The figure is a flow chart of the method of the present invention.

[0024] Description of Reference Numerals

[0025] 1. BDO organic waste liquid fixed bed gasifier, 2. BDO organic waste liquid fluidized flow gasifier, 3. Product heat exchanger, 4. Heat exchanger, 5. Gas-liquid-solid separation tank, 6. Gas heat exchanger, 7. Gas compressor, 8. Liquid mixer, 9. Water electrolysis hydrogen production system, 10. Gas-liquid separation tank. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention clearer and more concise, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] like Figure 1 and Figure 2As shown, after the BDO organic waste liquid passes through the BDO organic waste liquid fixed bed gasifier 1, the BDO organic waste liquid macromolecules are decomposed into BDO organic waste liquid small molecules, and the BDO organic waste liquid small molecules enter the BDO organic waste liquid fluidized bed gasifier 2 for gasification reaction, and a certain amount of oxygen gasifying agent is added to make it fully gasify at a temperature of 744° C. The product heat exchanger 3 and the heat exchanger 4 are used for cooling, and then enter the gas-solid-liquid separation tank 5 to separate the generated substances, and the gas flows out from the top of the gas-solid-liquid separation tank 5, and the sodium carbonate solid and ash flow out from the bottom of the gas-solid-liquid separation tank 5. The synthesis gas enters the gas heat exchanger 6. After the synthesis gas is heated by the gas heat exchanger 6, it enters the gas compressor 7 for compression and packaging, and can be sent to users. The waste discharged from the top of the gas-solid-liquid separation tank 5 is part of methane, carbon dioxide, etc., and the generated ash and sodium carbonate solid are discharged from the bottom. The water produced by the BDO organic waste liquid fluidized flow gasifier 2 is discharged from the middle of the gas-solid-liquid separation tank 5 and mixed with a certain amount of fresh water into the liquid mixer 8, and then enters the electrolytic water hydrogen production system 9. The produced substances are separated through the gas-liquid separation tank 10, and hydrogen and oxygen flow out from the top. The hydrogen is sold, and the oxygen enters the BDO organic waste liquid fluidized flow gasifier 2 as a gasifying agent to provide energy for the gasification reaction. The unreacted water flows out from the bottom of the gas-liquid separation tank 10 and returns to the electrolytic water hydrogen production system 9 to continue the reaction. The heat generated in the BDO organic waste liquid fluidized flow gasifier 2 is transferred to the electrolytic water hydrogen production system 9, and the heat required by the electrolytic water system is provided by the BDO organic waste liquid fluidized flow gasifier. The heat generated by the cooling of the product heat exchanger 3 is transferred to the gas heat exchanger 6 for heating the gas heat exchanger 6, so as to fully utilize the heat.

[0028] Example 1: BDO organic waste liquid is introduced into a BDO organic waste liquid fixed bed gasifier 1 at 200°C and 0.1 MPa, and the BDO organic waste liquid macromolecules are decomposed into organic small molecules such as C, H, O, and N, and then sprayed into a BDO organic waste liquid fluidized bed gasifier 2 with oxygen as the gasifying agent, and gasification reaction is carried out at 744°C and 0.7 MPa to generate CO, CO 2 , H 2 , CH 4 、N 2 、Na 2 CO 3 NH 3 , H 2O, HCL and other molecules enter the product heat exchanger 3 for heat exchange and cooling to 632℃, and then enter the heat exchanger 4 for further cooling to 33.61℃. After two steps of cooling, the product enters the gas-solid-liquid separation tank 5 to separate the product. Synthesis gas and waste flow out from the top of the tower, and sodium carbonate solid and ash flow out from the bottom of the tower. The synthesis gas at the top of the gas-solid-liquid separation tank 5 is heated to 300℃ by the gas heat exchanger 6 and then enters the 5MPa gas compressor 7 and is packaged and delivered to the user. The water produced by the BDO organic waste liquid fluidized flow gasifier 2 is discharged from the middle of the gas-solid-liquid separation tank 5 and mixed evenly with a certain amount of fresh water in the liquid mixer 8 and then enters the 0.6MPa water electrolysis hydrogen production system 9. The amount of fresh water is determined by the amount of oxygen produced by the water electrolysis hydrogen production system. The water electrolysis hydrogen production system mainly converts water into hydrogen and oxygen with a conversion rate of 0.8. The hydrogen, oxygen and unreacted water generated by the water electrolysis hydrogen production system 9 enter the gas-liquid separation tank 10 for separation, and the hydrogen and oxygen flow out from the top of the gas-liquid separation tank 10, the hydrogen is sold, and the oxygen enters the fluidized flow gasifier 2 as a gasifying agent to provide energy for the gasification reaction, and the unreacted water flows out from the bottom of the gas-liquid separation tank 10 and returns to the water electrolysis hydrogen production system 9 to continue the reaction. The heat generated by the temperature in the fluidized flow gasifier 2 is transferred to the water electrolysis hydrogen production system 9, and the heat provided by the fluidized flow gasifier 2 can completely meet the heat required by the electrolysis hydrogen production system 9. The heat generated by the product heat exchanger 3 is transferred to the gas heat exchanger 6 for heating the gas heat exchanger 6, and the heat provided by the product heat exchanger 3 can completely meet the heat required by the gas heat exchanger 6, so as to achieve full utilization of heat.

[0029] The results show that in the process of Example 1, the synthesis gas content reaches 64.9%, and the water recovery rate reaches 18.05%.

[0030] The present invention uses a gasification method to dispose of BDO tar residues and residual liquid. Compared with the traditional incineration method, no gaseous pollutants such as dioxins, nitrogen oxides, and sulfur oxides are generated during the process, and the emission of gaseous pollutants such as dust is also greatly reduced, and the environmental protection level is significantly improved. Recycling BDO in waste liquid can not only reduce the environmental pressure of waste liquid treatment, but also bring economic benefits to enterprises, which has important practical significance.

[0031] The present invention combines gasification with water electrolysis hydrogen production system to treat BDO organic waste liquid, which has great economic efficiency. Hydrogen produced by water electrolysis hydrogen production technology is widely used in energy chemical industry, aviation and aerospace, pharmaceutical, steel metallurgy and other fields. In addition, hydrogen will also have a huge market space in the fields of transportation, power generation, energy storage, etc. The produced oxygen can be supplied to the gasifier for use, realizing resource recycling.

Claims

1. A system for treating BDO organic waste liquid, characterized in that: The invention comprises a BDO organic waste liquid fixed bed gasification furnace (1), wherein the BDO organic waste liquid is introduced into the inlet of the BDO organic waste liquid fixed bed gasification furnace (1), the outlet of the BDO organic waste liquid fixed bed gasification furnace (1) is connected to the inlet of the BDO organic waste liquid fluidized flow gasification furnace (2), the outlet of the BDO organic waste liquid fluidized flow gasification furnace (2) is connected to the inlet of a product heat exchanger (3), the outlet of the product heat exchanger (3) is connected to the inlet of a heat exchanger (4), the outlet of the heat exchanger (4) is connected to the inlet of a gas-liquid-solid separation tank (5), waste gas is discharged from the top of the gas-liquid-solid separation tank (5), water separated from the middle of the gas-liquid-solid separation tank (5) is connected to a liquid mixer (8), ash and sodium carbonate are discharged from the bottom outlet of the gas-liquid-solid separation tank (5), and the gas-liquid-solid separation tank (5) is discharged from the bottom outlet. The top syngas outlet of the separation tank (5) is connected to the cold side inlet of the gas heat exchanger (6), and the hot side outlet of the gas heat exchanger (6) is connected to the gas compressor (7). The compressed gas is packaged and sent to the user. The liquid mixer (8) mixes the water separated from the gas-liquid-solid separation tank (5) with fresh water and then connects it to the inlet of the electrolytic water hydrogen production system (9). The outlet of the electrolytic water hydrogen production system (9) is connected to the gas-liquid separation tank (10). The oxygen outlet at the top of the gas-liquid separation tank (10) is connected to the inlet of the BDO organic waste liquid fluidized flow gasifier (2). The liquid water outlet at the bottom of the electrolytic water hydrogen production system (9) is connected to the electrolytic water hydrogen production system (9). The hydrogen produced by the electrolytic water hydrogen production is exported from the top of the gas-liquid separation tank (10).

2. The system for treating BDO organic waste liquid according to claim 1, characterized in that: The separation of synthesis gas and waste gas at the top of the gas-liquid-solid separation tank (5) and the separation of oxygen and hydrogen at the top of the gas-liquid separation tank (10) are achieved by arranging different gas permeable membranes in the gas pipelines in the gas-liquid-solid separation tank (5) and the gas-liquid separation tank (10), so as to achieve the separation of different gases according to the different permeation rates of different gases.

3. The system for treating BDO organic waste liquid according to claim 1, characterized in that: The BDO organic waste liquid fixed bed gasifier (1) is provided with a gasifier nozzle.

4. The system for treating BDO organic waste liquid according to claim 1, characterized in that: A quenching tank and an ash hopper are provided at the bottom of the gas-liquid-solid separation tank (5).

5. The system for treating BDO organic waste liquid according to claim 1, characterized in that: The heat of the BDO organic waste liquid fluidized flow gasification furnace (2) is transferred to the water electrolysis hydrogen production system (9).

6. The system for treating BDO organic waste liquid according to claim 1, characterized in that: The heat of the product heat exchanger (3) is transferred to the gas heat exchanger (6).

7. The operating method of the system for treating BDO organic waste liquid according to any one of claims 1 to 6, characterized in that: The steps include: Step 1: Treating BDO organic waste liquid by gasification: BDO organic waste liquid is introduced into a BDO organic waste liquid fixed bed gasifier (1) to decompose BDO organic waste liquid macromolecules into BDO organic waste liquid small molecules, and the BDO organic waste liquid small molecules then enter a BDO organic waste liquid fluidized flow gasifier (2) for gasification reaction, and are cooled by a product heat exchanger (3) and a heat exchanger (4), and are separated by a gas-liquid-solid separation tank (5). The top portion is the synthesis gas and part of the methane and carbon dioxide wastes produced by the gasification reaction, and part of the methane and carbon dioxide wastes are discharged. The synthesis gas produced at the top is heated by a gas heat exchanger (6) and then enters a compressor (7) for compression and is then delivered to a user. The bottom portion of the gas-liquid-solid separation tank (5) is the ash produced and the sodium carbonate solid is packaged and sold; Step 2: Electrolysis of water to produce hydrogen: The water produced by the BDO organic waste liquid fluidized flow gasifier (2) is separated in the middle of the gas-liquid-solid separation tank (5) and enters the liquid mixer (8) together with fresh water, and then enters the electrolytic water hydrogen production system (9). The gas from the electrolytic water hydrogen production system (9) enters the gas-liquid separation tank (10). The oxygen separated at the top of the gas-liquid separation tank (10) enters the BDO organic waste liquid fluidized flow gasifier (2) as a gasifying agent for the gasification reaction. The hydrogen separated at the top of the gas-liquid separation tank (10) is sold. The liquid water that has not reacted completely in the electrolytic water hydrogen production system (9) is separated by the gas-liquid separation tank (10) and then returns to the electrolytic water hydrogen production system (9) to continue the reaction.

8. The working method according to claim 7, characterized in that: In step 1, the gasification reaction is carried out under normal pressure at a temperature of 600-1000°C, and the temperature of the synthesis gas after heat exchange in the gas heat exchanger (6) is 300°C.

9. The working method according to claim 7, characterized in that: In step 2, the efficiency of converting water in the water electrolysis hydrogen production system (9) into hydrogen and oxygen is more than 68% and is related to the water feed. The water separated by the gas-liquid-solid separation tank (10) is used as the raw material for water electrolysis hydrogen production. If the generated oxygen is not enough to supply the entrained flow gasifier (2) for gasification reaction, an appropriate amount of fresh water is added to the liquid mixer (8) according to the oxygen consumption, or an appropriate amount of oxygen is directly introduced into the BDO organic waste liquid entrained flow gasifier (2).

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