CN216171284U - Safe and energy-saving RTO air inlet ammonium salt pre-removing device - Google Patents
Safe and energy-saving RTO air inlet ammonium salt pre-removing device Download PDFInfo
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- CN216171284U CN216171284U CN202122705236.3U CN202122705236U CN216171284U CN 216171284 U CN216171284 U CN 216171284U CN 202122705236 U CN202122705236 U CN 202122705236U CN 216171284 U CN216171284 U CN 216171284U
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Abstract
The utility model discloses a safe and energy-saving RTO (regenerative thermal oxidizer) intake ammonium salt pre-removing device, which comprises an acid washing pretreatment spray tower, a pre-mixing filter, an RTO incineration device, an alkali washing acid removal spray tower and an exhaust chimney, wherein the acid washing pretreatment spray tower is connected with the pre-mixing filter; the pre-mixing filter comprises a main pre-mixing filter and a standby pre-mixing filter which are connected in parallel; the two pre-mixing filters are correspondingly connected with the pickling pretreatment spray tower at the air inlet ends, are correspondingly connected with the RTO incineration device at the air outlet ends, and are respectively provided with an air inlet valve for waste gas to be treated at the air inlet ends. According to the device, free halogen in low-temperature flue gas after combustion and ammonia amine in waste gas to be treated are fully reacted and crystallized, so that ammonium salt is crystallized and separated out on a heat storage ceramic body of the filter in advance, the components such as ammonia amine in the waste gas can be effectively prevented from entering the RTO incineration device, the heat storage ceramic body in the RTO incineration device is prevented from being blocked by various substances such as ammonium chloride, ammonium sulfite and triethylamine hydrochloride, and the applicability and safety of the RTO incineration device are improved.
Description
Technical Field
The utility model relates to the technical field of organic waste gas purification treatment, in particular to a safe and energy-saving RTO (regenerative thermal oxidizer) intake ammonium salt pre-removing device.
Background
Heat accumulation formula thermal incinerator (RTO) among the prior art, because of it has adopted ceramic heat accumulation technique, when guaranteeing higher waste gas incineration temperature (steerable at 700 ~ 1000 ℃), greatly reduced the operation energy consumption, become the exhaust-gas treatment mode that is widely adopted at present, typical RTO among the prior art burns the device's work flow as follows:
and a first circulation step: low-temperature waste gas enters the oxidation chamber from the heat storage chamber 1, the oxidized smoke is discharged through the heat storage chamber 2, and meanwhile, the heat storage chamber 3 is purged;
and a second circulation step: low-temperature waste gas enters the oxidation chamber from the heat storage chamber 2, the oxidized smoke is discharged through the heat storage chamber 3, and the heat storage chamber 1 is purged at the same time;
and a third circulating step: low-temperature waste gas enters the oxidation chamber from the heat storage chamber 3, the oxidized smoke is discharged through the heat storage chamber 1, and meanwhile, the heat storage chamber 2 is swept;
the above three steps are continuously circulated, and in the process, the porous heat storage ceramic body plays the following role in the contact type heat storage heat exchanger: in the process of entering and exiting waste gas, a temperature gradient is formed from top to bottom by the heat storage ceramic body, the incineration temperature of the oxidation chamber can reach 700-1000 ℃, and the temperature of the bottom of the ceramic body can be lowered to below 60 ℃; the exhaust heat of the previous cycle is absorbed by the heat storage ceramic body and then is transferred to the intake air of the next cycle for heating; and the air inlet regenerator in the previous cycle step is used as an exhaust chamber of the next cycle after being purged by clean air because the concentration of the waste gas is relatively high.
A typical RTO incineration device can play a good energy-saving role in treating low-concentration organic waste gas, and is usually 800-1500 mg/m in a specific concentration range (according to the calorific value of organic substances3) In addition, the RTO incineration device can realize heat balance, namely, the temperature of the oxidation chamber is maintained to the maximum extent through the heat generated by the self-oxidation of the waste gas, and the consumption of other fuels or energy is reduced.
The RTO incineration device is widely used in the fine chemical industry and the pharmaceutical chemical industry at present, and because the waste gas components in the industries are often complex and usually contain ammonia (amine), hydrogen sulfide, halogenated hydrocarbon, sulfide (mercaptan, thioether) and other pollutants, the phenomenon that a heat storage ceramic body of the RTO incineration device is blocked by ammonium salt is often caused in actual field application, so that the RTO incineration device needs to be frequently stopped, cleaned and overhauled; if the cleaning is not timely, the bed pressure is too large, the heat exchange effect is poor, and the temperature at the bottom of the hearth is too high, so that fire, explosion and other dangers occur.
In the prior art, the waste gas before entering into the RTO is generally pretreated by adopting an acid/alkali spray tower, and the simple spray pretreatment can reduce the concentration of ammonia (amine) in the waste gas but cannot completely remove the ammonia (amine); the spraying pretreatment has lower effect on removing organic halide in the waste gas, and after the incineration treatment of the oxidation chamber, the organic halide/sulfide is oxidized and decomposed into free inorganic small molecules such as SO2 and CO2、HCl、H2O and the like, and a small amount of residual substances exist in the bottom chamber of the RTO furnace in the exhaust process(ii) a In the next gas inlet circulation, the ammonia (amine) -containing substances in the waste gas to be treated are easy to react with HCl and SO remained in the chamber due to the low temperature when passing through the bottom of the RTO furnace2And the reaction is carried out, so that substances such as ammonium sulfite, ammonium chloride, triethylamine hydrochloride and the like are generated, the heat storage ceramic body is blocked, and finally the equipment cannot normally operate.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a safe and energy-saving RTO (regenerative thermal oxidizer) intake ammonium salt pre-removing device aiming at the defects in the prior art, and the technical scheme is as follows:
a safe and energy-saving RTO air inlet ammonium salt pre-removing device comprises an acid washing pretreatment spray tower, a pre-mixing filter, an RTO incineration device, an alkali washing acid removal spray tower and an exhaust chimney which are sequentially connected; the pre-mixing filter comprises a main pre-mixing filter and a standby pre-mixing filter which are connected in parallel; the two pre-mixing filters are correspondingly connected with the pickling pretreatment spray tower at the air inlet ends, are correspondingly connected with the RTO incineration device at the air outlet ends, and are respectively provided with an air inlet valve for waste gas to be treated and an air outlet valve for pre-mixing filtration at the air outlet ends.
The RTO incineration device and the alkali cleaning acid spray tower are also provided with a backflow flue gas pipeline between, the end part of the backflow flue gas pipeline is connected with the two pre-mixing filters respectively through a backflow flue gas regulating valve, and the backflow flue gas pipeline is also provided with a backflow flue gas stop valve.
Further, each pre-mixing filter contains a bulk heat storage ceramic body, and a pressure difference meter is arranged in parallel on each pre-mixing filter.
Further, the concentration of the waste gas introduced by the return flue gas pipeline is set to be 5% -15% of the waste gas at the outlet end of the RTO incineration device.
Further, an explosion lower limit detector is further arranged at the gas inlet end of the pickling pretreatment spray tower.
Further, the inlet end of the RTO incineration device is also provided with an RTO front fan and a flame arrester, and the outlet end of the RTO incineration device is correspondingly provided with an RTO rear fan.
Furthermore, an oxidation chamber is arranged in the RTO incineration device, a burner and a plurality of regenerative chambers are arranged in the oxidation chamber, and waste gas from the premixing processor enters the regenerative chambers through circulation steps after being shunted.
Furthermore, a cleaning fan is further arranged in the RTO incineration device, and a plurality of cleaning pipelines are arranged on the cleaning fan and connected to the corresponding regenerative chambers.
Has the advantages that: the utility model has the following beneficial effects:
(1) the device is characterized in that a set of premixed filter containing heat storage ceramic in bulk and used for gas mixing is arranged on an inlet waste gas pipeline of an RTO incineration device, part of low-temperature halogen-containing smoke gas discharged by the RTO incineration device is led back to the premixed filter to be mixed with organic waste gas to be treated, free halogen in the low-temperature smoke gas after combustion is utilized to fully react and crystallize with ammonium amine in the waste gas to be treated, so that ammonium salt is crystallized and separated out on a heat storage ceramic body of the filter in advance, and the components such as ammonium amine in the waste gas can be effectively prevented from entering the RTO incineration device, prevents various substances such as ammonium chloride, ammonium sulfite, triethylamine hydrochloride and the like from blocking a heat storage ceramic body in the RTO incineration device, thereby further widening the application of the RTO incineration device in the field of waste gas treatment and improving the applicability and the safety of the RTO incineration device in the treatment of the waste gas with complex components in the fine chemical industry;
(2) the device is characterized in that at least one set of a used filter and one set of a spare filter are arranged on a premixing filter, pressure difference meters are respectively arranged at the front and the back of the premixing filter, when the front and the back pressure difference of the premixing filter exceed a set value for alarming, a gas circuit is switched to a spare table, when the front and the back pressure difference of the premixing filter rise, ammonium salt crystals on a filter medium are more, after the gas circuit is switched to the spare premixing filter, the used premixing filter accumulated with ammonium salt is cleaned, and a disassembly cleaning or online water washing mode can be selected according to the field condition; through the switching of the two pre-mixing filters, ammonium amine which is likely to form salt in waste gas and cause blockage of a heat storage ceramic body can be filtered out in advance under the condition that normal operation of the RT0 incineration device is not influenced, and the applicability and the safety of the RTO incineration device are improved.
Drawings
FIG. 1 is a schematic view of the structure of the present invention.
Detailed Description
The present invention will be further illustrated with reference to the accompanying drawings and specific examples, which are carried out on the premise of the technical solution of the present invention, and it should be understood that these examples are only for illustrating the present invention and are not intended to limit the scope of the present invention.
As shown in fig. 1, a safe and energy-saving RTO intake air ammonium salt pre-removing device comprises an acid washing pretreatment spray tower 1, a pre-mixing filter, an RTO incineration device 3, an alkali washing acid removal spray tower 4 and an exhaust chimney 5 which are connected in sequence; the pre-mixing filter comprises a main pre-mixing filter 21 and a standby pre-mixing filter 22 which are connected in parallel; the two pre-mixing filters are correspondingly connected with the pickling pretreatment spray tower 1 at the air inlet ends, and correspondingly connected with the RTO incineration device 3 at the air outlet ends, and the air inlet ends of the two pre-mixing filters are respectively provided with an air inlet valve 23 for waste gas to be treated, and the air outlet ends of the two pre-mixing filters are respectively provided with an air valve 24 for pre-mixing filtration.
Still be provided with backward flow flue gas pipeline 6 between RTO incinerator 3 and the alkali wash acid spray tower 4, this backward flow flue gas pipeline 6's tip again through the backward flow flue gas governing valve 7 that sets up with link to each other with two premix filters respectively, and still install backward flow flue gas trip valve 8 on the backward flow flue gas pipeline 6.
Each pre-mixing filter contains a bulk heat storage ceramic body, and a pressure difference meter 25 is also arranged in parallel on each pre-mixing filter; the concentration of the waste gas introduced by the return flue gas pipeline 6 is set to be 5-15% of the waste gas at the outlet end of the RTO incineration device 3.
An explosion lower limit detector 9 is also arranged at the gas inlet end of the pickling pretreatment spray tower 1; the inlet end of the RTO incineration device 3 is also provided with an RTO front fan 31 and a flame arrester 32, and the outlet end of the RTO incineration device 3 is correspondingly provided with an RTO rear fan 33.
The RTO incineration device 3 is internally provided with an oxidation chamber 34, a burner 35 and a plurality of regenerative chambers 36 are arranged in the oxidation chamber 34, and waste gas from the premixing processor enters the regenerative chambers 36 through circulation steps after being shunted; the RTO incineration device 3 is also provided with a cleaning fan 37, and the cleaning fan 37 is provided with a plurality of cleaning pipelines connected to the corresponding regenerative chambers 36.
The core technology of the device is that gaseous free halogen in low-temperature smoke discharged from an outlet of the RTO incineration device is mixed and pretreated with low-concentration ammonia (amine) in waste gas to be treated, and a specific bulk heat storage ceramic body is adopted to promote the reaction to form salt and crystallize and separate out, so that the applicability of the RTO incineration device to the waste gas with complex components is improved. The technology abandons the idea of removing ammonia (amine) by increasing the number of stages of the acid spray tower without limitation, and does not adopt the traditional idea of guiding high-temperature flue gas from the hearth of the RTO furnace to carry out warming pretreatment on the high-temperature flue gas, thereby avoiding huge energy consumption loss and potential safety hazard brought by the high-temperature flue gas.
The device adopts a gas premixing filter mode to solve the problem that a heat storage ceramic body is easily blocked by ammonium salt in the RTO incineration treatment process of organic waste gas containing ammonia (including inorganic ammonia and organic amine), halogen (organic matters containing halogen such as chlorine, bromine and the like) and sulfide, and the working process and the principle are as follows:
the organic waste gas containing ammonia (including inorganic ammonia and organic amine) and halogen (organic matters containing halogen such as chlorine, bromine and the like) and sulfide to be treated is pretreated by a front-end acid washing pretreatment spray tower, so that the concentration of ammonia (amine) in the waste gas is fully reduced.
The waste gas after acid washing pretreatment enters a pre-mixing filter; meanwhile, a certain proportion of waste gas is led out from the outlet flue gas of the RTO incineration device and is sent into a premixing filter, and the proportion can be adjusted according to the concentration of the waste gas, generally 5-15%.
Since chlorine (including other halogens) containing organic matters are generally difficult to remove by spray washing and the like, but after high-temperature incineration, organic molecules are destroyed, halogen/sulfide become free and are easy to combine with gaseous ammonia (amine) to form salt, and then ammonia (amine) in the waste gas to be treated reacts with acidic pollutants in the flue gas after incineration in the pre-mixing filter and is crystallized and precipitated.
Ammonia (amine) in the waste gas is subjected to one-stage or multi-stage acid washing pretreatment, and the concentration of the ammonia (amine) can be reduced to a lower level; however, the cost for completely removing ammonia (amine) is high, the blockage of the heat storage ceramic body in the RTO incineration device can still be caused after the acid pickling pretreatment, but free chlorine (halogen) and sulfide in the incinerated flue gas exist in a gaseous form, the molecular diffusion speed is higher, the effective molecular collision rate for promoting the reaction is higher, and the bulk heat storage ceramic body in the pre-mixing filter provides a good condition for the crystallization precipitation of ammonium salt, so that low-concentration ammonia (amine) in the waste gas can be more effectively removed
The pre-mixing filter of the device is internally provided with the bulk heat storage ceramic body, so that the gas can be fully mixed and salified to crystallize; and the premixing filter of the device is provided with one set for use and one set for standby, pressure difference meters are respectively arranged in front of and behind the filter, when the pressure difference in front of and behind the filter exceeds a set value for alarming, the gas circuit is switched to a standby table, when the pressure difference in front of and behind the premixing filter rises, ammonium salt crystals on the filter medium are more, after the gas circuit is switched to the standby table, the used filter with the accumulated ammonium salt is cleaned, and a disassembly cleaning or online water washing mode can be selected according to the field situation.
The specific switching working process is as follows: the waste gas to be treated enters a pre-mixing filter after being subjected to acid washing pretreatment on ammonia (amine) substances by a front-end spray tower; the device is only shown by a first-stage pickling spray tower, and can be adjusted according to the concentration condition of waste gas in engineering practice.
When the RTO incineration device is started, taking the main pre-mixing filter in fig. 1 as an example, the exhaust gas inlet valve at the front end of the main pre-mixing filter and the pre-mixing filtering outlet valve at the rear end are opened, the backflow flue gas stop valve is opened at the same time, the backflow flue gas regulating valve connected to the main pre-mixing filter is opened to the maximum, the exhaust gas to be treated after acid washing pretreatment and the backflow flue gas in the RTO incineration device are mixed in the main pre-mixing filter, and the exhaust gas passes through the main pre-mixing filter and then enters the RTO incineration device for incineration treatment.
In the operation process, the opening degree of the backflow valve can be adjusted according to the concentration proportion of ammonia (amine) containing substances in the waste gas components and acidic pollutants in the outlet flue gas, and the opening degree of the backflow flue gas adjusting valve is preferably 5-15% of the total exhaust gas quantity of the RTO incineration device.
When the main premixing filter and the RTO incineration device stably operate, the pressure difference representation number of the main premixing filter is recorded in real time, when the representation number of the pressure difference representation exceeds a preset alarm value, a waste gas inlet valve, a premixing filtering outlet valve and a backflow flue gas regulating valve at two ends of the standby premixing processor are opened, all valve bodies on the main premixing processor are correspondingly closed, the standby premixing filter is started, and then the main premixing filter is disassembled and cleaned or flushed by on-line water.
When the pressure difference representation number of the standby premixing filter exceeds the set high-order alarm value, the waste gas is switched back to the channel of the main premixing filter in the steps, and the standby premixing filter is cleaned, so that the standby premixing filter can be used continuously in a circulating mode.
Through the switching of the two premixing filters, ammonium salt (amine) which is possibly salified in waste gas and causes the blockage of the heat storage ceramic body can be filtered out in advance under the condition that the normal operation of the RTO is not influenced.
The ammonium salt pre-removing technology of the device fully utilizes the characteristics of the waste gas, and other anions except for waste gas pollution factors are not introduced in the ammonium salt removing process, so that the amount of waste ammonium salt is controlled to the minimum, and all the ammonium salt comes from pollutants contained in the waste gas; the application of the technology correctly grasps the mechanism of forming ammonium salt in the heat-storage ceramic body of the RTO incineration device, adopts low-temperature flue gas to remove ammonia (amine) substances in waste gas, and has stronger safety and feasibility in operation.
The above-mentioned embodiments are only preferred embodiments of the present invention, and are not intended to limit the scope of the utility model and the appended claims, and all equivalent changes and modifications made within the spirit and scope of the utility model as claimed should be included in the appended claims.
Claims (7)
1. The utility model provides a safe energy-conserving RTO air inlet ammonium salt is desorption device in advance which characterized in that: comprises an acid-washing pretreatment spray tower (1), a pre-mixing filter, an RTO incineration device (3), an alkali-washing acid-removing spray tower (4) and an exhaust chimney (5) which are connected in sequence; the pre-mixing filter comprises a main pre-mixing filter (21) and a standby pre-mixing filter (22) which are connected in parallel; the gas inlet ends of the two pre-mixing filters are respectively and correspondingly connected with the pickling pretreatment spray tower (1), the gas outlet ends of the two pre-mixing filters are respectively and correspondingly connected with the RTO incineration device (3), the gas inlet ends of the two pre-mixing filters are respectively provided with a waste gas inlet valve (23) to be treated, and the gas outlet ends of the two pre-mixing filters are respectively provided with a pre-mixing filtration gas outlet valve (24);
RTO incineration device (3) and alkali wash and remove sour spray tower (4) between still be provided with backward flow flue gas pipeline (6), the tip of this backward flow flue gas pipeline (6) again through backward flow flue gas governing valve (7) that set up with link to each other with two premix filters respectively, and still install backward flow flue gas trip valve (8) on backward flow flue gas pipeline (6).
2. The safe and energy-saving RTO intake ammonium salt pre-removing device according to claim 1, characterized in that: each pre-mixing filter contains a bulk heat storage ceramic body, and a pressure difference meter (25) is further arranged in parallel on each pre-mixing filter.
3. The safe and energy-saving RTO intake ammonium salt pre-removing device according to claim 1, characterized in that: the concentration of the waste gas introduced by the return flue gas pipeline (6) is set to be 5-15% of the waste gas at the outlet end of the RTO incineration device (3).
4. The safe and energy-saving RTO intake ammonium salt pre-removing device according to claim 1, characterized in that: and an explosion lower limit detector (9) is also arranged at the air inlet end of the pickling pretreatment spray tower (1).
5. The safe and energy-saving RTO intake ammonium salt pre-removing device according to claim 1, characterized in that: the inlet end of the RTO incineration device (3) is also provided with an RTO front fan (31) and a flame arrester (32), and the outlet end of the RTO incineration device (3) is correspondingly provided with an RTO rear fan (33).
6. A safe and energy-saving RTO inlet air ammonium salt pre-removing device according to claim 5, characterized in that: the RTO incineration device (3) is internally provided with an oxidation chamber (34), a burner (35) and a plurality of regenerators (36) are arranged in the oxidation chamber (34), and waste gas from the premixing processor enters the regenerators (36) through a circulation step after being shunted.
7. A safe and energy-saving RTO inlet air ammonium salt pre-removing device according to claim 6, characterized in that: the RTO incineration device (3) is also provided with a cleaning fan (37), and the cleaning fan (37) is provided with a plurality of cleaning pipelines connected to corresponding regenerators (36).
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| Application Number | Priority Date | Filing Date | Title |
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| CN202122705236.3U CN216171284U (en) | 2021-11-05 | 2021-11-05 | Safe and energy-saving RTO air inlet ammonium salt pre-removing device |
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| CN202122705236.3U CN216171284U (en) | 2021-11-05 | 2021-11-05 | Safe and energy-saving RTO air inlet ammonium salt pre-removing device |
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