CN111569529A - Method for rapidly processing faults of dry quenching discharge device - Google Patents
Method for rapidly processing faults of dry quenching discharge device Download PDFInfo
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- CN111569529A CN111569529A CN202010311509.3A CN202010311509A CN111569529A CN 111569529 A CN111569529 A CN 111569529A CN 202010311509 A CN202010311509 A CN 202010311509A CN 111569529 A CN111569529 A CN 111569529A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D39/00—Filtering material for liquid or gaseous fluids
- B01D39/02—Loose filtering material, e.g. loose fibres
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
- C10B41/00—Safety devices, e.g. signalling or controlling devices for use in the discharge of coke
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Abstract
The invention discloses a method for rapidly processing faults of a coke dry quenching discharge device, and belongs to the field of coke dry quenching. The provided method comprises the following steps: the method can quickly process faults to restore production, ensure the personal safety of workers, protect the property safety of enterprises and has wide popularization and application prospect.
Description
Technical Field
The invention belongs to the field of dry quenching, and particularly relates to a method for rapidly processing faults of a dry quenching discharge device.
Background
The dry quenching technology is mainly characterized in that red hot coke at the temperature of about 1000 ℃ is pushed into a coke tank from a coke oven carbonization chamber, the coke tank filled with the red hot coke is lifted to the top of a dry quenching furnace by a lifter, and the red hot coke is loaded into the dry quenching furnace by a loading device. And hot coke is loaded from the upper part of the dry quenching furnace, is conveyed to a cooling chamber through a pre-storage chamber, directly exchanges heat with circulating inert gas, the inert gas after heat exchange of the dry quenching furnace is heated to 900-980 ℃, and enters a dry quenching boiler for heat exchange after dust removal of a primary dust remover. High-temperature and high-pressure steam generated by the dry quenching boiler is conveyed to a steam turbine generator unit for power generation or other uses. The coke after heat exchange is cooled to below 180 ℃, discharged by a coke discharging device at the bottom of the dry quenching furnace and sent to a coke table coke conveying belt.
The coke dry quenching discharge device is an important component in the production of a coke dry quenching system, the continuous and stable coke discharge amount is one of the most main conditions for the stability of the technological parameters of the whole coke dry quenching system, and plays an important role in the water supply and steam production of a coke dry quenching boiler and the stable operation of a coke dry quenching power generation system. The discharging device requires automatic, continuous and uniform discharging, and no circulating gas and dust escape during coke discharging. The device consists of an electric gate, a vibration feeder, a rotary sealing valve, a coke discharging chute and other equipment. If the discharging device has faults and can not be timely discharged in a short time, the coke cooled by the dry quenching furnace can not be discharged, so that the dry quenching furnace is in a high material level and the coke can not be loaded, and the dry quenching integral production system can not stably run. In addition, the dry quenching discharge device is positioned at the positive pressure section of the circulating gas system, great potential safety hazards exist in the overhauling process, toxic, harmful, flammable and explosive gases such as carbon monoxide, hydrogen sulfide and nitrogen oxide can be leaked due to improper operation, personal injury is caused to operators, and even the life safety is threatened.
The dry quenching discharge device fault is one of the chronic diseases of dry quenching production and is an important factor influencing the dry quenching rate and the improvement of the power generation quantity. The key to rapidly process faults and recover production is to realize the safety control of the whole process on the basis of process control and assist with careful production organization. From the aspect of accident prevention, the coke dry quenching and the last process are managed intensively, impurities such as ironware and the like are prevented from entering the coke dry quenching furnace from the source, and the method is a fundamental measure for avoiding blockage of the rotary sealing valve.
Disclosure of Invention
In view of one or more of the problems in the prior art, the present invention provides a method of rapidly handling a dry quenching discharge device failure, comprising the steps of:
1) treatment of exhaust device circulating gas leakage
Firstly, a central control room is contacted to check whether the pressure of a dry quenching furnace and a gas circulation system is abnormal, if so, the pressure is adjusted to a normal range according to the abnormal reason, and then whether the circulation gas is still leaked is continuously observed;
secondly, checking whether the circulating gas leaks from the discharge device by a soapy water smearing method, and if so, immediately repairing after finding a leakage point; if the leakage amount of the circulating gas is large, replacement of spare parts is immediately organized to remove faults;
2) ejector rotary seal valve plugging process
Firstly, a continuous circulating fan treatment mode is adopted, and when the size of foreign matters is small, the foreign matters can be discharged through field reversal operation or combination of positive and negative rotation of the rotary sealing valve; if the coke can not be discharged, stopping coke charging, and closing the vibration feeder and the nitrogen charging point of the rotary sealing valve; when the rotary sealing valve is powered off, stopping the belt from running, and closing the coke-loading dust removal valve; fully opening the rotary valve to seal the upper dust removal point valve; after the process adjustment is completed and the personnel are in place, monitoring the content of the circulating gas at any time by using CO alarm or sensing whether the pressure at the position of the personnel is positive by using hands, and if the pressure is positive, withdrawing the personnel and continuing to perform the process adjustment; if the pressure is negative, gradually opening the manhole, and wearing an air respirator before entering the rotary sealing valve to take out the foreign matters until the fault treatment is finished;
secondly, a circulating fan stopping treatment mode is adopted, a power generation adjusting system is informed, and the circulating fan is stopped after wind is gradually reduced; closing all nitrogen charging points of the vibration feeder and the rotary sealing valve; according to the actual situation on site, after confirming that safety matters are adopted in production, immediately opening an inspection manhole at the upper part of the rotary sealing valve to observe the specific blocking situation; determining a processing mode according to a specific jam condition; and after the foreign matters are taken out and no abnormity is observed, the coupler and the upper and lower manhole cover parts are installed immediately, and normal production is recovered.
The above method further comprises the steps of:
3) prevention of clogging of a rotary seal valve of a discharge device
Firstly, reinforcing maintenance and point inspection of a dry quenching coke tank and a loading device, and preventing a lining plate and a distributor sealing plate from entering a dry quenching furnace;
secondly, in the coking process, tools, furnace wall graphite and locomotive devices are prevented from entering a coking chamber or a coke tank in the production management; when the ironware enters the coke tank in the coke pushing process, the coke dry quenching system is informed in time so that the coke dry quenching system can estimate the discharge time of the ironware according to the entering time of the ironware, prepare for treating jamming, reduce the influence on production and rapidly treat faults.
The method for rapidly processing the faults of the dry quenching discharge device based on the technical scheme can rapidly solve the problem of the faults of the dry quenching device, furthest reduce the influence on the dry quenching rate and the power generation amount from the perspective of a production process, and reduce the quality reduction and the economic loss of coke. Meanwhile, through careful production organization, the process is simple, toxic, harmful, flammable and explosive gas is prevented from leaking in the overhauling process, the personal safety of workers is ensured, the property safety of enterprises is protected, and the popularization and application prospects are wide.
Drawings
Fig. 1 is a schematic view of a dry quenching discharge device.
Detailed Description
The invention aims to provide a method for rapidly processing faults of a coke dry quenching discharge device so as to guide the rapid solving of the faults of the coke dry quenching device in actual production.
The present invention will be described in detail with reference to specific examples, which are provided only for better understanding of the present invention and do not limit the present invention.
As shown in fig. 1, a schematic structural diagram of a coke dry quenching discharge device is shown, which mainly comprises an electric gate 1, a vibratory feeder 2, a rotary sealing valve 3 and a coke discharging chute 4, and when the discharge device fails, the failure of the discharge device can be quickly handled according to the following steps, specifically comprising:
1. exhaust device circulating gas leakage treatment
1.1, when a circulating gas leakage accident occurs, safety warning measures should be taken immediately, and maintenance personnel entering a gas leakage area must wear effective protective equipment such as a respirator and the like.
1.2, when the circulating gas leakage accident happens and the safety protection of maintenance personnel is well guaranteed, firstly, the central control room is contacted to check whether the pressure of the dry quenching furnace and the gas circulating system is abnormal, if so, the pressure is adjusted to a normal range according to the abnormal reason, and then whether the circulating gas leakage still exists is continuously observed.
1.3, secondly, checking whether each flange interface, a compensator, a sealing ring and a casing of the discharging device equipment leak by using a soapy water smearing method, checking whether a lower-section lining plate fixing bolt hole and a material blocking rod mounting hole of the gas supply device leak, and immediately repairing after finding a leakage point.
1.4, if the leakage amount of the circulating gas is large, replacement spare parts should be immediately organized to remove faults.
2. Ejector rotary seal valve plugging process
2.1 adopting a non-stop circulating fan processing mode
a. Generally, when the size of the foreign matter is small, it can be discharged by the field reverse operation or the combination of the forward and reverse rotation of the rotary seal valve.
b. And if the sealing valve is manually rotated in the positive and negative directions twice, the temperature of the motor of the sealing valve is monitored, and if the sealing valve is found to be increased, the operation is stopped immediately.
c. When the sealing valve is manually operated, a specially-assigned person is arranged to monitor the belt corridor, and when a foreign body falls on the belt, the belt is immediately stopped to run, so that the belt is prevented from being damaged.
d. And after manual operation has no effect, closing the overhaul gate valve at the bottom of the dry quenching furnace.
e. Stopping coke charging, and reducing the circulating air volume to 10 ten thousand meters3And h, adjusting other parameters according to needs and informing a power generation system to adjust the power generation load so as to ensure the stability and the durability of power generation.
f. And closing all nitrogen filling points of the vibration feeder and the rotary sealing valve.
g. And the rotary sealing valve is powered off, and the belt stops running.
h. And closing the dust removal gate valve on the coke discharging chute and closing the coke loading dust removal valve.
i. The environmental dust removal air quantity is improved to 20 ten thousand meters3/h。
j. The fully opened rotary valve seals the upper dust removing point valve.
k. After the process adjustment is completed and the personnel are in place, carrying a CO alarm, drilling one bolt at an interval, monitoring the content of the circulating gas at any time by using the CO alarm or sensing whether the positive pressure exists at the manhole by using a hand in the process of loosening the bolt, if so, withdrawing the maintainer from the process to continue the adjustment, and if so, gradually opening the manhole.
m, if the foreign matter is taken out, the maintenance personnel enters the sealing valve to take out the foreign matter, CO and O are used2The content O in the rotary seal valve is monitored by an alarm2When the concentration is more than 20% and the CO content is less than or equal to 50ppm, the gas can enter the rotary sealing valve to process faults; meanwhile, the maintainer has to tie the safety belt and at least two people nearby monitor the safety belt. Meanwhile, a measure for preventing the sealing valve from being scalded by high temperature is made.
Preparing an air respirator as an emergency protection tool, and wearing the air respirator once a foreign body needs to be taken out by entering the rotary sealing valve; and after the maintenance worker arrives, the operation personnel assist the maintenance worker to process until the fault processing is finished.
2.2 adopt the treatment mode of stopping the circulating fan
a. And informing an operator of the power generation adjusting system to stop the circulating fan after the wind is gradually reduced.
b. The on-site necessary tools comprise a hook, a U-shaped buckle, a lighting lamp, 4 12-inch wrenches, 1 guide chain table of 2 tons, 2 rope buckles, 2 shovels, 1 crowbar and 1 silicon plate with the thickness of 4mm2Or 6 meters of 12mm graphite packing, 1 flashlight, 1 axial flow fan, 2 CO alarm instruments and O 22 alarm instruments, 1 warning sign, 1 maintenance tablet.
c. The maintainer can replace the labor protection product in the shortest time and arrive at the appointed site to participate in the first-aid repair.
d. And closing all nitrogen filling points of the vibration feeder and the rotary sealing valve.
e. According to the actual situation on site, after the safety matters are confirmed to be adopted in production, the upper overhaul manhole of the rotary sealing valve is immediately opened to observe the specific blocking situation.
f. According to the specific jam condition, determining different processing modes:
a) in the first case, the coke between the vanes of the rotary seal valve contains large foreign matters, and the operation in the forward and reverse directions is disabled.
The failure processing method is that the foreign matters are taken out by a hook or other methods, and the manhole cover is recovered.
b) The second situation is that the metal at the front end of the blade of the rotary sealing valve is loosened or the fastening bolt falls off, so that when the rotary sealing valve rotates forwards, the metal moves outwards and is clamped, the operation cannot be performed, and when the rotary sealing valve operates backwards, the metal falls back and operates normally.
The fault processing method is to rotate the rotor reversely to a proper position to make the loose front metal fall back to a normal position, and the front metal is firmly welded with the blade body by electric welding. And installing the manhole cover plate and recovering normal production.
c) The third situation is that the upper manhole door is opened for inspection, no foreign matter or abnormality is found, and the rotary sealing valve cannot operate in the forward and reverse directions, so that the rotary sealing valve blade and the shell are plugged by the foreign matter at the most.
The fault processing method comprises the following steps: 1) and immediately arranging and disassembling the connecting bolt of the coupling and the lower manhole door. 2) And arranging a chain block at a preset position. 3) The blade is clamped on the blade by a preset clamp and firmly scraped by a chain block. 4) Confirming that the coupling has been disengaged. 5) And operating the chain block to strive for making the blades rotate in the opposite direction. 6) In the process of operating the chain block, personnel at the upper inspection manhole pay close attention to the rotation condition of the blade and the existence of foreign objects. 7) And immediately stopping the chain rewinding operation after the foreign matters appear. 8) And after the foreign matter is taken out, the operation of chain rewinding is continued. 9) And after the observation is continued, the parts such as the coupling, the upper manhole cover and the lower manhole cover are installed immediately. 10) And recovering normal production.
2.3 prevention of jamming of Rotary seal valves
1) The maintenance and point inspection of the coke dry quenching tank and the loading device are enhanced, and a lining plate, a distributor sealing plate and the like are prevented from entering the dry quenching furnace.
2) In the coking process, tools, furnace wall graphite, locomotive (coke pusher, coke guide, coal charging car) devices and the like are prevented from entering a coking chamber or a coke tank in production management.
3) If the ironware and the like enter the coking chamber during coal charging, the record should be timely recorded, and the wet quenching operation should be carried out on the coking chamber, and if the ironware enters the coking chamber during coke pushing, the dry quenching operation should be immediately stopped and the wet quenching operation should be changed into the wet quenching operation.
4) When ironware and the like enter the coke tank in the coke pushing process, the coke dry quenching system is informed in time so that the coke dry quenching system can estimate the discharge time of the ironware according to the entering time of the ironware, prepare for treating jamming and reduce the influence on production as much as possible.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (2)
1. A method of rapidly handling dry quenching discharge device failure, comprising the steps of:
1) treatment of exhaust device circulating gas leakage
Firstly, a central control room is contacted to check whether the pressure of a dry quenching furnace and a gas circulation system is abnormal, if so, the pressure is adjusted to a normal range according to the abnormal reason, and then whether the circulation gas is still leaked is continuously observed;
secondly, checking whether the circulating gas leaks from the discharge device by a soapy water smearing method, and if so, immediately repairing after finding a leakage point; if the leakage amount of the circulating gas is large, replacement of spare parts is immediately organized to remove faults;
2) ejector rotary seal valve plugging process
Firstly, a continuous circulating fan treatment mode is adopted, and when the size of foreign matters is small, the foreign matters can be discharged through field reversal operation or combination of positive and negative rotation of the rotary sealing valve; if the coke can not be discharged, stopping coke charging, and closing the vibration feeder and the nitrogen charging point of the rotary sealing valve; when the rotary sealing valve is powered off, stopping the belt from running, and closing the coke-loading dust removal valve; fully opening the rotary valve to seal the upper dust removal point valve; after the process adjustment is completed and the personnel are in place, monitoring the content of the circulating gas at any time by using CO alarm or sensing whether the pressure at the position of the personnel is positive by using hands, and if the pressure is positive, withdrawing the personnel and continuing to perform the process adjustment; if the pressure is negative, gradually opening the manhole, and wearing an air respirator before entering the rotary sealing valve to take out the foreign matters until the fault treatment is finished;
secondly, a circulating fan stopping treatment mode is adopted, a power generation adjusting system is informed, and the circulating fan is stopped after wind is gradually reduced; closing all nitrogen charging points of the vibration feeder and the rotary sealing valve; according to the actual situation on site, after confirming that safety matters are adopted in production, immediately opening an inspection manhole at the upper part of the rotary sealing valve to observe the specific blocking situation; determining a processing mode according to a specific jam condition; and after the foreign matters are taken out and no abnormity is observed, the coupler and the upper and lower manhole cover parts are installed immediately, and normal production is recovered.
2. The method of claim 1, further comprising the steps of:
3) prevention of clogging of a rotary seal valve of a discharge device
Firstly, reinforcing maintenance and point inspection of a dry quenching coke tank and a loading device, and preventing a lining plate and a distributor sealing plate from entering a dry quenching furnace;
secondly, in the coking process, tools, furnace wall graphite and locomotive devices are prevented from entering a coking chamber or a coke tank in the production management; when the ironware enters the coke tank in the coke pushing process, the coke dry quenching system is informed in time so that the coke dry quenching system can estimate the discharge time of the ironware according to the entering time of the ironware, prepare for treating jamming, reduce the influence on production and rapidly treat faults.
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| CN112079063A (en) * | 2020-09-11 | 2020-12-15 | 科世茂机械设备（兴化）有限公司 | Dry quenching rotary seal valve |
| CN113403091A (en) * | 2021-05-21 | 2021-09-17 | 五冶集团上海有限公司 | Method for online blocking blowby of vault masonry of primary coke dry quenching dust remover |
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| CN112079063A (en) * | 2020-09-11 | 2020-12-15 | 科世茂机械设备（兴化）有限公司 | Dry quenching rotary seal valve |
| CN113403091A (en) * | 2021-05-21 | 2021-09-17 | 五冶集团上海有限公司 | Method for online blocking blowby of vault masonry of primary coke dry quenching dust remover |
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