阅读说明：本技术 一种废弃物焚烧/熔炼系统的环保经济化处理方法 (Environment-friendly and economical treatment method for waste incineration/smelting system ) 是由 李智 于 2021-07-16 设计创作，主要内容包括：本发明属于环保领域,其公开了一种废弃物焚烧/熔炼系统的环保经济化处理方法,所述方法涉及用于制备液氮和液氧的空气液化分离系统、用于焚烧和/或熔炼废弃物的炉体,所述炉体上设有与炉体相通的烟道,所述烟道的出口连接有除尘装置；所述方法具体为：将空气液化分离系统生产的液氧气化后与空气混合后注入炉体中用于助燃；将空气液化分离系统生产的液氮通过喷雾头喷入烟道内,使烟道内的烟气在2s内降温至200℃以下。该方法能够有效控制尾气二噁英的生成,能够有效降低设备投资、运行成本。(The invention belongs to the field of environmental protection, and discloses an environment-friendly and economical treatment method of a waste incineration/smelting system, which relates to an air liquefaction separation system for preparing liquid nitrogen and liquid oxygen and a furnace body for incinerating and/or smelting waste, wherein the furnace body is provided with a flue communicated with the furnace body, and an outlet of the flue is connected with a dust removal device; the method specifically comprises the following steps: liquid oxygen produced by the air liquefaction separation system is gasified and then mixed with air, and then the mixture is injected into the furnace body for supporting combustion; and liquid nitrogen produced by the air liquefaction separation system is sprayed into the flue through the spray head, so that the temperature of flue gas in the flue is reduced to below 200 ℃ within 2 seconds. The method can effectively control the generation of the tail gas dioxin, and can effectively reduce equipment investment and operation cost.)

1. An environment-friendly and economical treatment method of a waste incineration/smelting system relates to an air liquefaction separation system for preparing liquid nitrogen and liquid oxygen and a furnace body for incinerating and/or smelting waste, wherein a flue communicated with the furnace body is arranged on the furnace body, and an outlet of the flue is connected with a dust removal device; the method is characterized by comprising the following steps:

liquid oxygen produced by the air liquefaction separation system is gasified and then mixed with air, and then the mixture is injected into the furnace body for supporting combustion;

and liquid nitrogen produced by the air liquefaction separation system is sprayed into the flue through the spray head, so that the temperature of flue gas in the flue is reduced to below 200 ℃ within 2 seconds.

2. The environment-friendly economical treatment method of the waste incineration/melting system as set forth in claim 1, wherein the flue comprises a horizontally arranged flue cavity, baffles are alternately arranged in the flue cavity from top to bottom in sequence, and a spray head is arranged at the top of the flue cavity; one end of the flue cavity is an inlet and the other end is an outlet.

3. The method of environmentally friendly and economical treatment of a waste incineration/melting system according to claim 2, wherein a plurality of fly ash discharge ports are provided at the bottom of the flue cavity.

4. The environmentally friendly and economical process for treating a waste incineration/melting system as set forth in claim 1, wherein the dust removal device is a bag dust removal device.

5. The environmentally friendly and economical treatment method of a waste incineration/melting system according to claim 1, wherein the combustion-supporting gas injected into the furnace body includes not less than 70 vol% of oxygen and the balance of air.

6. The environmentally friendly and economical processing method of a waste incineration/melting system according to claim 1, wherein the furnace body is a furnace body of an oxygen-rich side-blown furnace.

7. The method of claim 1, wherein a first temperature sensor is disposed at an inlet of the flue, a second temperature sensor is disposed at an outlet of the flue, the spray head is collected in a liquid nitrogen supply pipe, a control valve is disposed on the liquid nitrogen supply pipe, and the first temperature sensor, the second temperature sensor and the control valve are electrically connected to a controller, respectively.

Technical Field

The invention relates to the field of environmental protection, in particular to an environment-friendly and economical treatment method of a waste incineration/smelting system.

Background

CN201610397500.2 discloses a treatment method and a device for treating dioxin in incineration flue gas. According to the treatment method, the flue gas and the smoke dust containing dioxin generated by incineration are introduced into the treatment device, the flue gas and the smoke dust are sufficiently oxidized, combusted and filtered through the liquid melt contained in the device, active carbon compounds such as carbon particles and CO are completely converted into inert carbon compounds such as CO2, and the treated flue gas is removed due to the active carbon compounds, so that the condition that the dioxin is jointly synthesized by elements such as carbon, chlorine, oxygen, hydrogen and the like in the flue gas in the temperature change process of the flue gas is avoided. Furthermore, flue gas and smoke dust containing dioxin generated by burning of boilers, incinerators, smelting furnaces and the like can be directly treated by the device; waste plastics containing chlorine, waste electronic circuit boards, and the like may be directly fed into the apparatus to be subjected to a combustion reaction.

CN201610194702.7 discloses a processing apparatus of dioxin class atmospheric pollutants in high temperature flue gas. Belongs to a method for removing organic halogen compounds in flue gas. The device is characterized in that the processing device is composed of the following devices which are connected in sequence: the system comprises a primary reinforced combustion furnace, a secondary reinforced combustion furnace, a silicon nitride porous ceramic filter, a countercurrent heat exchange waste heat boiler, a combined heat pipe heat exchanger, a filter bag dust removal system, an acid gas removal system, an active carbon adsorption tower and an induced draft fan; the utility model provides a processing apparatus of dioxin class atmospheric pollutants in high temperature flue gas that not only waste heat recovery is efficient, moreover can be to in the high temperature flue gas production and the processing procedure, the dioxin class (dioxins) atmospheric pollutants that carry on effectively administering. All items of the atmospheric pollutants are lower than the limit values specified in the table 4 of GB18485-2014 'control standard of municipal solid waste incineration pollutants'. Wherein the emission amount of dioxin-like atmospheric pollutants is less than or equal to 0.1ngTEQ/m 3.

The existing dioxin treatment mode mainly comprises two aspects, namely, firstly, the combustion temperature is high enough, and secondly, the tail gas is sufficiently treated.

Even if the combustion is carried out fully, dioxin is easy to generate when the temperature of the flue is reduced. The optimum temperature for producing dioxin is 300 ℃, but above 400 ℃, dioxin is still likely to be produced. The smoke exhaust temperature is generally 500 ℃. Therefore, if the generation of dioxin in the flue is to be suppressed, a high-speed temperature reduction is considered.

It is known that cooling by water or refrigerant is common. In the prior art, the flue gas is cooled mainly by water gasification and heat absorption. However, the adoption of water mist for cooling has many disadvantages:

the disadvantages are as follows: if the temperature is required to be quickly reduced, the water mist amount is large, and if the water mist amount is large, the phenomenon that a lot of water mist is intercepted by a cloth bag of the cloth bag dust remover or water vapor is condensed into water in the cloth bag dust remover to cause cloth bag blockage is avoided.

Namely, the water mist quantity has to take the cooling speed and the condensation speed into consideration, and the two have to find a delicate balance.

The disadvantages are as follows: the water mist needs to build a cooling tower with large floor area and the like, and the equipment investment is relatively large.

The use of other cooling agents, such as liquid nitrogen, is generally not so useful because the liquid nitrogen is very expensive and the use of liquid nitrogen to reduce the temperature can result in significant increases in the cost of tail gas treatment.

In solid waste treatment plants, more and more enterprises adopt an adsorption method to prepare oxygen. Because the adoption of the compressor and the distillation tower for preparing the liquid oxygen requires three shifts of workers on one hand and the one-time investment of equipment is relatively large on the other hand, the adoption of the compressor and the distillation tower for preparing the liquid oxygen is abandoned by small and medium-sized waste treatment enterprises.

The adsorption method for preparing oxygen is not beneficial and harmless, and the molecular sieve is expensive, the service life of the molecular sieve is limited, the oxygen preparation purity is not high, the oxygen preparation efficiency is low, and the integral cost ratio is not lower than that of a compressor and a distillation tower for preparing liquid oxygen with the same equivalent.

As a medium-large solid waste treatment enterprise, the Hunan gold environmental protection technology limited company of the department of China has the requirement of combustion-supporting gas of 700 cubic meters per minute for each smelting furnace.

From an economic point of view, it is desirable to have a very economical and environmentally friendly system for the relevant production.

Disclosure of Invention

The invention aims to provide an environment-friendly and economical treatment method for a waste incineration/smelting system, which can effectively control the generation of tail gas dioxin and effectively reduce equipment investment and operation cost.

In order to achieve the purpose, the invention provides the following technical scheme: an environment-friendly and economical treatment method of a waste incineration/smelting system relates to an air liquefaction separation system for preparing liquid nitrogen and liquid oxygen and a furnace body for incinerating and/or smelting waste, wherein a flue communicated with the furnace body is arranged on the furnace body, and an outlet of the flue is connected with a dust removal device; the method specifically comprises the following steps:

liquid oxygen produced by the air liquefaction separation system is gasified and then mixed with air, and then the mixture is injected into the furnace body for supporting combustion;

and liquid nitrogen produced by the air liquefaction separation system is sprayed into the flue through the spray head, so that the temperature of flue gas in the flue is reduced to below 200 ℃ within 2 seconds.

In the environment-friendly economical treatment method of the waste incineration/smelting system, the flue comprises a horizontally arranged flue cavity, baffles are sequentially and alternately arranged in the flue cavity from top to bottom, and the top of the flue cavity is provided with a spray head; one end of the flue cavity is an inlet and the other end is an outlet.

In the above method for environment-friendly and economical treatment of a waste incineration/smelting system, the bottom of the flue cavity is provided with a plurality of fly ash discharge ports.

In the above method for environment-friendly and economical treatment of a waste incineration/smelting system, the dust removal device is a cloth bag dust removal device.

In the above method for environmentally and economically treating a waste incineration/melting system, the combustion-supporting gas injected into the furnace body includes not less than 70 vol% of oxygen and the balance of air.

In the environment-friendly and economical treatment method of the waste incineration/smelting system, the furnace body is an oxygen-enriched side-blown furnace body.

In the above method for environment-friendly economical treatment of a waste incineration/melting system, a first temperature sensor is arranged at an inlet of the flue, a second temperature sensor is arranged at an outlet of the flue, the spray head is collected in a liquid nitrogen supply pipe, a control valve is arranged on the liquid nitrogen supply pipe, and the first temperature sensor, the second temperature sensor and the control valve are respectively and electrically connected to a controller.

Compared with the prior art, the invention has the beneficial effects that:

the invention takes the factors of production scale, production cost and the like into consideration, an air liquefaction separation system is arranged, long-term production can be realized by one-time investment, the produced liquid oxygen is mixed with air and added into an oxygen-enriched side-blown furnace for solid waste smelting, the furnace temperature is also increased, and the consumption of natural gas is reduced. The liquid nitrogen produced by the method is directly sprayed into a flue in an atomization mode, and the temperature is reduced to below 200 ℃ in a delay within 2 s.

Generally, it is difficult for those skilled in the art to think of using liquid nitrogen to rapidly cool and remove dioxin, on one hand, few plants have oxygen generation equipment, enterprises with large-scale oxygen generation equipment generally do not burn wastes which are easy to generate dioxin, and outsourcing liquid nitrogen is expensive, so that the scheme of the invention cannot be imagined by general people or can be eliminated in the first time.

Compared with the traditional flue gas water cooling and molecular sieve oxygen generation mode, the method has the following specific advantages:

1. the liquid oxygen generated by the air liquefaction separation system has high purity, the economy is similar to that of molecular sieve oxygen generation, and the economy is better under the condition of moderate large scale after the material cost and purity of the molecular sieve oxygen generation are considered;

2. liquid oxygen generated by the air liquefaction separation system is mixed with air to support combustion, so that dioxin generated by combustion can be effectively decomposed, and the production of dioxin in flue gas is reduced;

3. the liquid nitrogen directly cools the flue gas and can reduce the temperature of the flue gas from 500 ℃ to 200 ℃ within 2 s.

4. The liquid nitrogen belongs to a byproduct of an air liquefaction separation system, and meanwhile, a water cooling tower with large occupied area in the traditional method is not needed, so that the construction and operation and maintenance cost can be effectively reduced.

Drawings

FIG. 1 is a schematic structural view of embodiment 1 of the present invention;

FIG. 2 is a cross-sectional view of a flue of example 1 of the present invention;

fig. 3 is a control block diagram of embodiment 1 of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Referring to fig. 1-3, a method for environment-friendly and economical treatment of a waste incineration/melting system, the method relates to an air liquefaction separation system 1 for preparing liquid nitrogen and liquid oxygen, a furnace body 2 for incinerating and/or melting waste, a flue 3 communicated with the furnace body 2 is arranged on the furnace body 2, and a dust removal device 4 is connected to the outlet of the flue 3; the dust removal device 4 is a cloth bag dust removal device 4; the method specifically comprises the following steps:

liquid oxygen produced by the air liquefaction separation system 1 is gasified and then mixed with air, and then the mixture is injected into the furnace body 2 for supporting combustion; the combustion-supporting gas injected into the furnace body 2 comprises oxygen not less than 70 vol% and the balance of air, and the enterprise is a solid waste treatment enterprise, so the furnace body 2 is the furnace body 2 of the oxygen-enriched side-blown furnace, and the embodiment can also be applied to a garbage disposal plant, and is also applied to the furnace body 2 for garbage incineration under the condition.

The liquid oxygen and air are mixed in a mixer 11 in advance with air and gasified in the mixer 11. The oxygen and air mixed well in the mixer 11 are injected into the furnace body 2 to support combustion.

Liquid nitrogen produced by the air liquefaction separation system 1 is sprayed into the flue 3 through the spray head 5, so that the temperature of flue gas in the flue 3 is reduced to below 200 ℃ within 2 seconds.

More specifically, a first temperature sensor 6 is arranged at the inlet of the flue 3, a second temperature sensor 7 is arranged at the outlet of the flue 3, the spray head 5 is collected in a liquid nitrogen supply pipe, a control valve 8 is arranged on the liquid nitrogen supply pipe, and the first temperature sensor 6, the second temperature sensor 7 and the control valve 8 are respectively and electrically connected to a controller 9. According to the production condition of the company, the first temperature sensor 6 is generally 450-; the second temperature sensor 7 needs to monitor whether the temperature exceeds 200 ℃, and if the temperature exceeds 200 ℃, the opening degree of the control valve 8 is increased.

As a typical air liquefaction separation system 1, reference may be made to "method and apparatus for obtaining compressed oxygen and compressed nitrogen by cryogenic separation of air", patent application No. 201180039066.6.

The flow velocity of flue gas in the flue 3 is generally 6-9 m/s, the whole flue is about 12-15 m long, and the structure of the flue is as follows: the device comprises a flue cavity 10 which is horizontally arranged, baffles 13 which are alternately arranged up and down in sequence in the flue cavity, and a spray head 5 is arranged at the top of the flue cavity 13; one end of the flue cavity 10 is an inlet and the other end is an outlet.

In the above-mentioned environmental-friendly and economical treatment method of the waste incineration/smelting system, the bottom of the flue cavity is provided with a plurality of fly ash discharge ports 12.

The flue gas and the nitrogen gasified by the liquid nitrogen are mixed through the baffle, the effect of high-speed cooling is generated, and the generation of dioxin is effectively inhibited.

Through detection, the air inlet temperature is 550 +/-20 ℃, the air outlet temperature is 180 +/-20 ℃, and dioxin is not detected.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.