阅读说明：本技术 一种垃圾飞灰协同垃圾渗滤液的在线处置系统及其工艺 (Online disposal system and process for garbage fly ash and garbage leachate ) 是由 王漫笠 刘富君 刘正宁 张露璐 宋德奎 于 2021-07-28 设计创作，主要内容包括：本发明公开了一种垃圾飞灰协同垃圾渗滤液的在线处置系统及其工艺,包括飞灰输送系统、等离子熔融炉系统、排渣收渣系统、垃圾渗滤液输送系统、二燃室及燃烧系统、余热锅炉系统、急冷塔、垃圾焚烧厂烟气净化系统。本发明通过等离子熔融炉完成垃圾飞灰的熔融玻璃态化,垃圾飞灰中的二噁英分解,通过急冷塔的急冷降温避免了二噁英的再生成,即使有少量的二噁英再生成,也会在飞灰的再循环中继续去除,完全保证了垃圾飞灰的无害化处置。本发明处理垃圾飞灰的同时可以协同处置垃圾渗滤液,将垃圾渗滤液送至二燃室中燃烧,彻底解决垃焚烧电厂渗滤液的问题；垃圾渗滤液燃烧所产生的的二噁英以及重金属也能通过垃圾飞灰的再循环得到彻底解决。(The invention discloses an online disposal system and a process for garbage fly ash and garbage leachate, which comprises a fly ash conveying system, a plasma melting furnace system, a slag discharging and collecting system, a garbage leachate conveying system, a secondary combustion chamber and combustion system, a waste heat boiler system, a quench tower and a flue gas purification system of a garbage incineration plant. The invention finishes the melting glass fluidization of the garbage flying ash through the plasma melting furnace, decomposes the dioxin in the garbage flying ash, avoids the regeneration of the dioxin through the rapid cooling of the quench tower, can continuously remove the dioxin in the recycling of the flying ash even if a small amount of the dioxin is regenerated, and completely ensures the harmless treatment of the garbage flying ash. The invention can treat the garbage percolate in a synergic way while treating the garbage fly ash, and the garbage percolate is sent to a secondary combustion chamber for combustion, thereby thoroughly solving the problem of the percolate of the garbage incineration power plant; dioxin and heavy metals generated by the combustion of the landfill leachate can be thoroughly solved through the recycling of the landfill fly ash.)

1. An online disposal system of garbage fly ash and garbage leachate is characterized by comprising a fly ash conveying system, a plasma melting furnace system, a slag discharging and collecting system, a garbage leachate conveying system, a secondary combustion chamber and combustion system, a waste heat boiler system, a quench tower and a flue gas purification system of a garbage incineration plant; the fly ash conveying system, the plasma melting furnace system, the secondary combustion chamber and combustion system, the waste heat boiler system, the quench tower and the waste incineration plant flue gas purification system are sequentially communicated, the waste incineration plant flue gas purification system is communicated with the fly ash conveying system, a slag discharging port of the plasma melting furnace system is communicated with a slag discharging and collecting system, and the waste leachate conveying system is communicated with the secondary combustion chamber and the inlet end of the combustion system;

the fly ash conveying system conveys the garbage fly ash to the plasma melting furnace system;

the plasma melting furnace system melts the garbage fly ash under the high-temperature action of plasma and discharges the garbage fly ash as liquid slag, and simultaneously, the garbage fly ash is decomposed at high temperature to remove dioxin, and the flue gas carries a small part of fly ash to enter a secondary combustion chamber and a combustion system;

the slag discharging and collecting system collects liquid slag;

the garbage leachate conveying system conveys the garbage leachate into a secondary combustion chamber and a combustion system for combustion;

the secondary combustion chamber and the combustion system burn the received pyrolysis flue gas and the garbage percolate of the plasma melting furnace system;

the waste heat boiler system recovers the heat of the flue gas exhausted by the secondary combustion chamber and the combustion system;

the quenching tower rapidly cools the flue gas discharged by the waste heat boiler system;

the waste incineration plant flue gas purification system removes sulfur dioxide, nitrogen oxide and fly ash in the flue gas cooled by the quench tower.

2. The system of claim 1, wherein the fly ash conveying system comprises a bucket elevator and a screw feeder, the garbage fly ash is conveyed from the bucket elevator to a hopper storage bin at the upper part of the plasma melting furnace system, and the feeding amount of the garbage fly ash is controlled by the rotation speed of the screw feeder.

3. The system of claim 1, wherein the flue gas cleaning system of the waste incineration plant comprises a dust collector, and the dust collector captures and collects the waste fly ash and sends the waste fly ash to the fly ash conveying system for circulation.

4. The system of claim 1, wherein 2-4 afterburning nozzles are disposed in the second combustion chamber and the second combustion chamber of the combustion system.

5. The system of claim 1, wherein the secondary combustion chamber and the combustion system, the exhaust-heat boiler system, and the slag discharge port of the quench tower are communicated with a fly ash conveying system through a cooling device.

6. A process for the on-line disposal system of landfill fly ash in cooperation with landfill leachate according to any one of claims 1 to 5, wherein the process comprises the steps of:

s1: conveying the garbage fly ash: collecting fly ash in the waste incineration flue gas by a dust remover of a flue gas purification system of a waste incineration plant, and conveying the fly ash into a plasma melting furnace system by a fly ash conveying system;

s2: high-temperature melting treatment of the garbage fly ash: the garbage fly ash is sent into a plasma melting furnace system, unburned carbon is pyrolyzed and burned in the falling process, dioxin is decomposed again at high temperature, a small part of the garbage fly ash carried by flue gas enters a secondary combustion chamber system, most of the garbage fly ash is melted under the high-temperature action of plasma and is discharged as liquid slag, the liquid slag is collected by a slag discharging and collecting system, a vitreous body is formed after water cooling, and after heavy metals are separated and recovered, the vitreous body can be used as building materials or building material additives, so that the harmless treatment of the garbage fly ash is thoroughly realized;

s3: and (3) burning the garbage fly ash and the garbage percolate in a secondary combustion chamber: burning the received pyrolysis flue gas of the plasma melting furnace system and the garbage leachate sent by the garbage leachate conveying system in a secondary combustion chamber and a secondary combustion chamber of the combustion system;

s4: and (3) waste heat recovery process: flue gas combusted in the secondary combustion chamber enters a waste heat boiler system for waste heat recovery of the flue gas, and meanwhile, the exhaust gas temperature of the waste heat boiler system is set to be 550 ℃;

s5: quenching process: inputting the flue gas discharged by the waste heat boiler system into a quenching tower, and reducing the temperature of the flue gas from 550 ℃ to 180 ℃ by using atomized water carried by compressed air through a double-fluid spray gun;

s6: the flue gas enters a flue gas purification system of a waste incineration power plant for purification: and (3) sending the flue gas output from the quenching tower into a flue gas purification system of a waste incineration power plant to remove sulfur dioxide and nitric oxide in the flue gas, and simultaneously capturing a small amount of residual fly ash in the flue gas by a dust remover and then sending the captured fly ash to a fly ash conveying system for continuous circulation.

7. The process of claim 6, wherein in step S2, the temperature of the lower slag zone of the plasma melting furnace system is 1400-1600 ℃, the temperature of the flue gas outlet is 1100 ℃, and the plasma melting furnace system is filled with glass slag and limestone.

8. The process of claim 6, wherein in step S3, the residence time of the pyrolysis flue gas of the plasma melting furnace system in the secondary combustion chamber is 2-4S.

9. The process of claim 6, wherein in step S5, the time for reducing the temperature of the flue gas from 550 ℃ to 180 ℃ is 1S.

10. The process of claim 6, wherein in the steps S3, S4 and S5, the bottom slag dropped from the combustion chamber, the combustion system, the waste heat boiler system and the bottom of the quench tower is cooled and returned to the fly ash conveying system to be sent to the plasma melting furnace system for continuous circulation treatment.

Technical Field

The invention relates to hazardous waste disposal and comprehensive utilization in the field of environmental protection, in particular to an online disposal system and a process for garbage fly ash and garbage leachate.

Background

The fly ash of the waste incineration power plant is a highly toxic pollutant because the fly ash is enriched with dioxin and heavy metal with higher concentration, the fly ash of the waste incineration power plant is listed in a dangerous waste name book by the nation and can be discharged only by special treatment, the fly ash of the waste incineration power plant is mainly treated in a landfill form after the reaction of a chelating agent at present, but the common waste fly ash treatment technology can not meet the requirements along with the stricter environmental protection measures and the more and more difficult examination and approval of landfill sites; the leachate problem of the waste incineration plant is also one of the difficult problems to be treated by the waste incineration plant, and the common physical chemical or biological method has high treatment cost and high treatment difficulty.

In the actual operation process of the waste incineration power plant, the waste fly ash and the leachate are treated separately, and a new system or process is required to realize the reduction, harmlessness and resource final treatment of the waste fly ash and the leachate.

Disclosure of Invention

In order to solve the technical problems, the invention designs an online disposal system and a process for garbage fly ash and garbage leachate.

The invention adopts the following technical scheme:

an online disposal system of garbage fly ash and garbage leachate comprises a fly ash conveying system, a plasma melting furnace system, a slag discharging and collecting system, a garbage leachate conveying system, a secondary combustion chamber and combustion system, a waste heat boiler system, a quench tower and a flue gas purification system of a garbage incineration plant; the fly ash conveying system, the plasma melting furnace system, the secondary combustion chamber and combustion system, the waste heat boiler system, the quench tower and the waste incineration plant flue gas purification system are sequentially communicated, the waste incineration plant flue gas purification system is communicated with the fly ash conveying system, a slag discharging port of the plasma melting furnace system is communicated with a slag discharging and collecting system, and the waste leachate conveying system is communicated with the secondary combustion chamber and the inlet end of the combustion system;

the fly ash conveying system conveys the garbage fly ash to the plasma melting furnace system;

the plasma melting furnace system melts the garbage fly ash under the high-temperature action of plasma and discharges the garbage fly ash as liquid slag, and simultaneously, the garbage fly ash is decomposed at high temperature to remove dioxin, and the flue gas carries a small part of fly ash to enter a secondary combustion chamber and a combustion system;

the slag discharging and collecting system collects liquid slag;

the garbage leachate conveying system conveys the garbage leachate into a secondary combustion chamber and a combustion system for combustion;

the secondary combustion chamber and the combustion system burn the received pyrolysis flue gas and the garbage percolate of the plasma melting furnace system;

the waste heat boiler system recovers the heat of the flue gas exhausted by the secondary combustion chamber and the combustion system;

the quenching tower rapidly cools the flue gas discharged by the waste heat boiler system;

the waste incineration plant flue gas purification system removes sulfur dioxide, nitrogen oxide and fly ash in the flue gas cooled by the quench tower.

Preferably, the fly ash conveying system comprises a bucket elevator and a screw feeder, the garbage fly ash is conveyed to a hopper storage bin at the upper part of the plasma melting furnace system from the bucket elevator, and the feeding amount of the garbage fly ash is controlled by the rotating speed of the screw feeder.

Preferably, the flue gas purification system of the waste incineration plant comprises a dust remover, and the dust remover captures and collects waste fly ash and sends the waste fly ash to the fly ash conveying system for circulation.

Preferably, 2-4 afterburning nozzles are arranged in the second combustion chamber and the second combustion chamber of the combustion system.

Preferably, the second combustion chamber and the combustion system, the waste heat boiler system and the slag discharge port of the quench tower are communicated with a fly ash conveying system through a cooling device.

A process of an online disposal system for garbage fly ash and garbage leachate comprises the following steps:

s1: conveying the garbage fly ash: collecting fly ash in the waste incineration flue gas by a dust remover of a flue gas purification system of a waste incineration plant, and conveying the fly ash into a plasma melting furnace system by a fly ash conveying system;

s2: high-temperature melting treatment of the garbage fly ash: the garbage fly ash is sent into a plasma melting furnace system, unburned carbon is pyrolyzed and burned in the falling process, dioxin is decomposed again at high temperature, a small part of the garbage fly ash carried by flue gas enters a secondary combustion chamber system, most of the garbage fly ash is melted under the high-temperature action of plasma and is discharged as liquid slag, the liquid slag is collected by a slag discharging and collecting system, a vitreous body is formed after water cooling, and after heavy metals are separated and recovered, the vitreous body can be used as building materials or building material additives, so that the harmless treatment of the garbage fly ash is thoroughly realized;

s3: and (3) burning the garbage fly ash and the garbage percolate in a secondary combustion chamber: burning the received pyrolysis flue gas of the plasma melting furnace system and the garbage leachate sent by the garbage leachate conveying system in a secondary combustion chamber and a secondary combustion chamber of the combustion system;

s4: and (3) waste heat recovery process: flue gas combusted in the secondary combustion chamber enters a waste heat boiler system for waste heat recovery of the flue gas, and meanwhile, the exhaust gas temperature of the waste heat boiler system is set to be 550 ℃;

s5: quenching process: inputting the flue gas discharged by the waste heat boiler system into a quenching tower, and reducing the temperature of the flue gas from 550 ℃ to 180 ℃ by using atomized water carried by compressed air through a double-fluid spray gun;

s6: the flue gas enters a flue gas purification system of a waste incineration power plant for purification: and (3) sending the flue gas output from the quenching tower into a flue gas purification system of a waste incineration power plant to remove sulfur dioxide and nitric oxide in the flue gas, and simultaneously capturing a small amount of residual fly ash in the flue gas by a dust remover and then sending the captured fly ash to a fly ash conveying system for continuous circulation.

Preferably, in step S2, the temperature of the slag zone at the lower part of the plasma melting furnace system is 1400 to 1600 ℃, the temperature of the flue gas outlet is 1100 ℃, and the glass slag and the limestone are added into the plasma melting furnace system. During the reaction in the plasma melting furnace, a part of auxiliary materials (glass slag, limestone and the like) are added to improve the fluidity of the liquid slag.

Preferably, in step S3, the residence time of the pyrolysis flue gas of the plasma melting furnace system in the secondary combustion chamber is 2-4S.

Preferably, in step S5, the process time for reducing the temperature of the flue gas from 550 ℃ to 180 ℃ is 1S.

Preferably, in steps S3, S4, and S5, the bottom slag dropped from the bottom of the secondary combustion chamber, the combustion system, the exhaust-heat boiler system, and the quenching tower is cooled, returned to the fly ash conveying system, and sent to the plasma melting furnace system to continue the circulation treatment.

The invention has the beneficial effects that: (1) the invention treats the waste fly ash of the waste incineration power plant, the equipment can continuously run, the occupied area of the equipment is small, and the operation is convenient;

(2) the invention can completely complete the harmless treatment of the waste fly ash, the melting vitrification of the waste fly ash is completed through the plasma melting furnace, the dioxin in the waste fly ash is decomposed, the regeneration of the dioxin is avoided through the rapid cooling of the rapid cooling tower, even if a small amount of the dioxin is regenerated, the dioxin can be continuously removed in the recycling of the fly ash, and the harmless treatment of the waste fly ash is completely ensured;

(3) the invention can treat the garbage percolate in a synergic way while treating the garbage fly ash, and the garbage percolate is sent to a secondary combustion chamber for combustion, thereby thoroughly solving the problem of the percolate of the garbage incineration power plant; dioxin and heavy metals generated by the combustion of the landfill leachate can be thoroughly solved through the recycling of the fly ash;

(4) the invention does not need to add a separate flue gas purification treatment system, and the flue gas at the outlet of the system is connected into a flue gas purification system of a waste incineration power plant to remove a small amount of waste gas and fly ash generated by waste fly ash treatment and leachate combustion.

Drawings

FIG. 1 is a schematic diagram of one configuration of the system of the present invention;

in the figure: 1. a fly ash delivery system; 2. a plasma furnace system; 3. a slag discharging and collecting system; 4. a landfill leachate conveying system; 5. a second combustion chamber and a combustion system; 6. a waste heat boiler system; 7. a quench tower; 8. waste incineration factory gas cleaning system.

Detailed Description

The technical scheme of the invention is further described in detail by the following specific embodiments in combination with the attached drawings:

example (b): as shown in the attached figure 1, an online disposal system for garbage fly ash and garbage leachate comprises a fly ash conveying system 1, a plasma melting furnace system 2, a slag discharging and collecting system 3, a garbage leachate conveying system 4, a secondary combustion chamber and combustion system 5, a waste heat boiler system 6, a quench tower 7 and a flue gas purification system 8 of a garbage incineration plant; the fly ash conveying system, the plasma melting furnace system, the secondary combustion chamber and combustion system, the waste heat boiler system, the quench tower and the waste incineration plant flue gas purification system are sequentially communicated, the waste incineration plant flue gas purification system is communicated with the fly ash conveying system, a slag discharging port of the plasma melting furnace system is communicated with a slag discharging and collecting system, and the waste leachate conveying system is communicated with the secondary combustion chamber and the inlet end of the combustion system;

the fly ash conveying system conveys the garbage fly ash to the plasma melting furnace system;

the plasma melting furnace system melts the garbage fly ash under the high-temperature action of plasma and discharges the garbage fly ash as liquid slag, and simultaneously, the garbage fly ash is decomposed at high temperature to remove dioxin, and the flue gas carries a small part of fly ash to enter a secondary combustion chamber and a combustion system;

the slag discharging and collecting system collects liquid slag;

the garbage leachate conveying system conveys the garbage leachate into a secondary combustion chamber and a combustion system for combustion;

the secondary combustion chamber and the combustion system burn the received pyrolysis flue gas and the garbage percolate of the plasma melting furnace system;

the waste heat boiler system recovers the heat of the flue gas exhausted by the secondary combustion chamber and the combustion system;

the quenching tower rapidly cools the flue gas discharged by the waste heat boiler system;

the waste incineration plant flue gas purification system removes sulfur dioxide, nitrogen oxide and fly ash in the flue gas cooled by the quench tower.

The fly ash conveying system comprises a bucket elevator and a screw feeder, the garbage fly ash is conveyed to a hopper storage bin at the upper part of the plasma melting furnace system from the bucket elevator, and the feeding amount of the garbage fly ash is controlled by the rotating speed of the screw feeder.

The flue gas purification system of the waste incineration plant comprises a dust remover, and the dust remover catches and collects waste fly ash and sends the waste fly ash into a fly ash conveying system for circulation.

2-4 afterburning nozzles are arranged in the secondary combustion chamber and the secondary combustion chamber of the combustion system.

The second combustion chamber and the combustion system, the waste heat boiler system and the slag discharging port of the quench tower are communicated with a fly ash conveying system through a cooling device.

When the garbage fly ash is used in cooperation with the process of the on-line garbage leachate disposal system, a 200t/d household garbage incineration plant is taken as an example, and the daily fly ash treatment capacity is assumed to be 12 t. Lifting the garbage fly ash in the storage bin to a high-level hopper of a fly ash conveying system by a bucket elevator, wherein the storage capacity of the high-level hopper is set to be 250kg, the garbage fly ash is fed once in half an hour and is fed into a plasma melting furnace by a screw feeder at a set frequency; after the garbage fly ash enters a plasma melting furnace, unburned carbon in the fly ash forms pyrolysis gas at high temperature, most of the fly ash is melted at the high temperature of plasma to form liquid slag, and the liquid slag is discharged by water cooling to form a vitreous body; the flue gas discharged by the plasma melting furnace enters a secondary combustion chamber for continuous combustion, and the garbage percolate is conveyed into a combustor through a conveying system and is treated by 1m per hour³The secondary combustion chamber is provided with 2-4 afterburning nozzles, and the afterburning working medium can be natural gas or light diesel oil, so that the garbage leachate is prevented from generating unstable combustion due to too low heat value, the temperature of the hearth of the secondary combustion chamber is about 1100 ℃, andthe residence time of the flue gas in the secondary combustion chamber is about 2-4 s; the flue gas at the outlet of the secondary combustion chamber enters a waste heat boiler to exchange heat to about 550 ℃ so as to generate steam of about 1MPa and about 4t/h at 180 ℃; after the flue gas discharged by the waste heat boiler enters a quench tower, high-speed atomized water carried by compressed air is cooled to about 180 ℃ within 1s through a double-fluid spray gun, so that the regeneration of dioxin is avoided; the flue gas is sent into a flue gas purification system of a waste incineration plant through a pipeline for deep removal; after ash and slag dropping from the bottom of the secondary combustion chamber, the bottom of the waste heat boiler and the bottom of the quench tower are cooled, the ash and slag are collected and sent to the fly ash conveying system again to enter the plasma melting furnace for further treatment, and finally harmless, reduction and resource treatment and utilization of the garbage fly ash and leachate are completed.

The above-described embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention in any way, and other variations and modifications may be made without departing from the spirit of the invention as set forth in the claims.