CN214120111U - System for replacing coal mill hot primary air with flue gas discharged by internal combustion engine - Google Patents

Abstract

The utility model relates to a hot primary air system for replacing a coal mill of a coal-fired unit by smoke discharged by an internal combustion engine, which comprises the internal combustion engine, wherein a smoke discharge port of the internal combustion engine is connected with a denitration device through a pipeline, the outlet end of the denitration device is connected with a booster fan through a pipeline, the outlet end of the booster fan is connected with a hot primary air pipeline through a pipeline, the smoke discharged by the internal combustion engine is sent to the hot primary air pipeline after being boosted by the booster fan after being denitrated, a smoke baffle door is arranged on the pipeline between the booster fan and the hot primary air pipeline, the system comprises a smoke regulating air door, a smoke damper, a hot primary air pipeline and a coal mill, wherein the outlet end of the smoke damper is connected with the inlet end of the smoke regulating air door, the smoke damper is a shutoff door for isolated maintenance, the smoke regulating air door is a regulating air door for regulating the amount of smoke of an internal combustion engine entering the coal mill, the smoke regulating air door is used for controlling the amount of smoke entering the coal mill, and the hot primary air pipeline is connected with the coal mill; the utility model discloses both improved internal-combustion engine circulation efficiency, reduced the possibility of coal pulverizer natural explosion again, guaranteed the safe operation of unit.

Description

System for replacing coal mill hot primary air with flue gas discharged by internal combustion engine

[ technical field ]

The utility model belongs to the technical field of the internal-combustion engine smoke discharge technique and specifically relates to an internal-combustion engine discharges flue gas and replaces coal-fired unit coal pulverizer hot primary air system.

[ background art ]

At present, the heat of the smoke discharged by the internal combustion engine is directly discharged to the atmosphere through the smoke, and the temperature of the smoke discharged by the internal combustion engine is about 370 ℃, the oxygen content is about 10 percent, and the internal combustion engine has the characteristics of high temperature and low oxygen content. From data provided by various internal combustion engine plants, the cycle efficiency of the internal combustion engine with advanced technology is only about 46% under the condition of direct emission of flue gas at 370 ℃ in actual operation, and the power generation efficiency is poor. Meanwhile, the average annual utilization hour of the internal combustion engine is about 1500 hours, and the low power generation efficiency and the low power generation hour result in low investment income. If a waste heat boiler and a turbine generator are newly built like a traditional gas turbine unit for recovering the part of heat, the investment is high and the loss is not paid.

The coal-fired unit powder process system is mostly the malleation of cold primary air fan directly blows the system now, and the coal pulverizer is used to hot primary air from the primary air fan and get into the coal pulverizer from the air intake tangential of coal pulverizer lower part after the preheater heating, dry and carry the buggy, and this hot primary air oxygen content is higher for 21%. Meanwhile, in order to improve economic benefits, the coal-fired unit purchases more combustible and explosive coal types with lower standard coal unit price, and the coal types are extremely easy to naturally explode even if not controlled properly in the coal pulverizing process of the coal pulverizer.

[ contents of utility model ]

The utility model aims at solving foretell not enough and providing an internal-combustion engine discharges flue gas and replaces coal-fired unit coal pulverizer hot primary air system, has both improved internal-combustion engine circulation efficiency, has reduced the possibility of coal pulverizer natural explosion again, has guaranteed the safe operation of unit, has reduced coal fired power plant operating personnel operating pressure.

In order to achieve the purpose, the hot primary air system for replacing the coal mill of the coal mill by the smoke discharged by the internal combustion engine comprises the internal combustion engine 1, wherein a smoke discharge port of the internal combustion engine 1 is connected with a denitration device 2 through a pipeline, a chimney 3 is connected on the pipeline between the internal combustion engine 1 and the denitration device 2, the outlet end of the denitration device 2 is connected with a booster fan 4 through a pipeline, the outlet end of the booster fan 4 is connected with a hot primary air pipeline through a pipeline, the smoke discharged by the internal combustion engine 1 is sent to the hot primary air pipeline after being denitrated and boosted by the booster fan 4, a smoke damper door 5 and a smoke adjusting air door 6 are arranged on the pipeline between the booster fan 4 and the hot primary air pipeline, the outlet end of the smoke damper door 5 is connected with the inlet end of the smoke adjusting air door 6, the smoke damper door 5 is a shutoff door for isolation and maintenance, the smoke adjusting air door 6 is an adjusting air door for adjusting the smoke volume of the internal combustion engine entering the coal mill 7, the flue gas damper 6 is used for controlling the amount of flue gas entering the coal mill 7, and the hot primary air pipeline is connected with the coal mill 7.

Further, a hot primary air pipeline of the coal mill 7 is connected with an air preheater 8, and the air preheater 8 is respectively connected with a primary fan 9 and a blower 10.

Further, the coal mill 7 and the air preheater 8 are respectively connected with the combustor 11 through pipelines.

Further, a hot primary air pipeline of the coal mill 7 is connected with a sealing fan 12 through a pipeline, the sealing fan 12 is respectively connected with a coal feeder 13 and the coal mill 7, and the coal feeder 13 is connected with the coal mill 7.

Compared with the prior art, the utility model, have following advantage:

(1) the utility model discloses after the hot primary air of a certain coal pulverizer of coal-fired unit is replaced to internal-combustion engine exhaust flue gas, because of the direct internal-combustion engine cycle efficiency that utilizes of flue gas heat can promote by a wide margin, use the flue gas that oxygen content is low to carry out the drying to the coal pulverizer buggy simultaneously, can make coal-fired unit buggy natural possibility reduce by a wide margin to avoid the coal pulverizer to take place the spontaneous combustion explosion's condition, guaranteed the safe operation of unit, reduced coal fired power plant operating personnel's operating pressure;

(2) the utility model discloses replace any one coal pulverizer hot primary air of long term operation with internal-combustion engine flue gas, calculate according to flue gas oxygen content 10%, in order to satisfy the required oxygen of burning, the coal pulverizer group helps burning with cold secondary air volume increase limited, coal pulverizer total flue gas volume also increases limitedly in addition, the change that produces from this is little to influence such as air preheater, furnace heating surface heat transfer, wearing and tearing, so this scheme has performability;

(3) the utility model discloses an analysis can know and replace a certain coal pulverizer hot primary air back at adopting internal-combustion engine to discharge the flue gas, has both improved internal-combustion engine cycle efficiency, has reduced the possibility of coal pulverizer natural explosion again, and more thermal power generating unit safe operation has laid solid basis, is worth popularizing and applying.

[ description of the drawings ]

Fig. 1 is a schematic structural diagram of the present invention;

in the figure: 1. the device comprises an internal combustion engine 2, a denitration device 3, a chimney 4, a booster fan 5, a flue gas baffle door 6, a flue gas adjusting air door 7, a coal mill 8, an air preheater 9, a primary air fan 10, a blower 11, a combustor 12, a sealing fan 13 and a coal feeder.

[ detailed description of the invention ]

As shown in the attached drawing 1, the utility model provides an internal-combustion engine discharges flue gas and replaces hot primary air system of coal-fired unit coal pulverizer, utilizes this system, send to the hot primary air pipeline of the arbitrary powder process system of coal-fired unit after booster fan steps up behind the flue gas denitration that the internal-combustion engine discharged, through newly-increased flue gas throttle, control entering coal pulverizer smoke gas volume. The system comprises an internal combustion engine 1, a flue gas discharge port of the internal combustion engine 1 is connected with a denitration device 2 through a pipeline, a chimney 3 is connected on the pipeline between the internal combustion engine 1 and the denitration device 2, an outlet end of the denitration device 2 is connected with a booster fan 4 through a pipeline, an outlet end of the booster fan 4 is connected with a hot primary air pipeline through a pipeline, flue gas discharged by the internal combustion engine 1 is sent to the hot primary air pipeline after being boosted by the booster fan 4 after being denitrated, a flue gas baffle door 5 is arranged on the pipeline between the booster fan 4 and the hot primary air pipeline, the coal pulverizer comprises a flue gas adjusting air door 6, wherein the outlet end of the flue gas damper 5 is connected with the inlet end of the flue gas adjusting air door 6, the flue gas damper 5 is a shutoff door for isolation and maintenance, the flue gas adjusting air door 6 is an adjusting air door for adjusting the amount of flue gas of an internal combustion engine entering the coal pulverizer 7, the flue gas adjusting air door 6 is used for controlling the amount of flue gas entering the coal pulverizer 7, and a hot primary air pipeline is connected with the coal pulverizer 7. Wherein, a hot primary air pipeline of the coal mill 7 is connected with an air preheater 8, the air preheater 8 is respectively connected with a primary fan 9 and a blower 10, and the coal mill 7 and the air preheater 8 are respectively connected with a combustor 11 through pipelines; the hot primary air pipeline of the coal mill 7 is connected with a sealing fan 12 through a pipeline, the sealing fan 12 is respectively connected with a coal feeder 13 and the coal mill 7, and the coal feeder 13 is connected with the coal mill 7.

According to the actual operation conditions and characteristics of the on-site internal combustion engine and the large-capacity coal-fired unit and the actual operation conditions of the coal mill of the coal-fired unit, the flue gas discharged by the internal combustion engine is designed to replace a hot primary air system of a certain coal mill of the coal-fired unit, the oxygen content of the primary air is reduced, the coal mill is prevented from spontaneous combustion explosion, and the circulation efficiency of the internal combustion engine is further improved by directly utilizing the flue gas. The comparison and selection find that the flue gas parameters of the internal combustion engine are in accordance with the temperature and flow of the hot primary air of the large coal-fired unit. Under a rated working condition, the temperature of hot primary air of the coal mill unit is about 320 ℃, the air volume of the coal mill is more than 70 tons per hour, the air volume is gradually increased along with the increase of the unit capacity and the power of the coal mill, meanwhile, the temperature of flue gas discharged by the internal combustion engine is 370 ℃, and the condition that the flue gas of the internal combustion engine provides the hot primary air of the coal mill has feasibility.

The utility model discloses a flue gas is sent to the hot primary air pipeline of arbitrary powder process system of coal-fired unit through newly establishing booster fan behind the internal-combustion engine denitration, replaces the former coal-fired unit that the oxygen content is 21% from the heat supply primary air with the internal-combustion engine flue gas of oxygen content 10%, adjusts the flue gas through installing the hot-blast accent door on newly-increased pipeline, satisfies the dry and air volume and the temperature needs of carrying of coal-fired unit coal pulverizer. By implementing the scheme, the natural possibility of the coal powder of the coal pulverizing system can be greatly reduced, so that the situation of spontaneous combustion explosion of the coal mill is avoided. This system needs to increase coal electric set hot flue gas pipeline, flue gas air damper, flue gas damper, booster fan, wherein, (1) hot flue gas pipeline: and the pipeline is used for connecting the flue of the internal combustion engine to the booster fan, the booster fan to the flue gas baffle and the air damper, and connecting the flue gas damper to the hot primary air main pipe of the coal mill. (2) Flue gas damper: and the air damper is used for adjusting the smoke quantity of the internal combustion engine entering the coal mill. (3) Flue gas baffle door: a shutoff door for isolating the overhaul. (4) A booster fan: the booster fan is additionally arranged to enable the pressure of the smoke of the internal combustion engine to be consistent with the pressure of a primary air main pipe of the original coal mill.

The invention will be further described with reference to the following specific examples:

the normal 18MW internal combustion engine rated working condition discharged smoke gas amount is 100 tons per hour, the rated air amount of the coal-fired unit coal mill is more than 70 tons per hour, and the method is feasible by replacing any coal-fired unit coal mill hot primary air with the internal combustion engine discharged smoke gas in the aspect of parameter matching when the coal-fired unit operates for a long time. The case is that after the part of the flue gas discharged by the 18MW internal combustion engine is subjected to denitration and then is pressurized by a booster fan, after the flue gas is adjusted by a flue gas adjusting air door according to the requirement of the coal mill, the flue gas with certain temperature and pressure is sent to a hot primary air pipeline of a coal-electric machine unit bottom powder preparation system, and according to the set value of the outlet temperature of the coal mill and the load condition of the coal mill, a newly-added flue gas damper and an original cold primary air damper of the coal mill are adjusted together to meet the requirements of the outlet temperature and output of the coal mill.

The smoke of the internal combustion engine with the oxygen content of 10 percent is used as hot primary air, so that the pulverized coal is not easy to reach the spontaneous combustion condition, the natural possibility of the pulverized coal of the coal-fired unit is greatly reduced, the coal mill operated by the internal combustion engine unit for a long time does not generate spontaneous combustion explosion, and the safety and the reliability of the coal-fired unit are greatly improved. Meanwhile, the circulation efficiency of the internal combustion engine can be greatly improved after the flue gas of the internal combustion engine is utilized, and the benefit of the whole power plant is improved. The implementation of the project has better economic benefit and safety benefit, and especially has application value when the coal price is higher and combustible, explosive and cheap coal with a large amount of volatile components and low high heat value needs to be combusted.

The present invention is not limited by the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be equivalent replacement modes, and are all included in the protection scope of the present invention.

Claims (4)

1. The utility model provides a hot primary air system of coal-fired unit coal pulverizer is replaced to internal-combustion engine exhaust gas, includes internal-combustion engine (1), the fume emission mouth of internal-combustion engine (1) passes through pipe connection denitrification facility (2), be connected with chimney (3) on the pipeline between internal-combustion engine (1) and denitrification facility (2), its characterized in that: the outlet end of the denitration device (2) is connected with a booster fan (4) through a pipeline, the outlet end of the booster fan (4) is connected with a hot primary air pipeline through a pipeline, the flue gas discharged by the internal combustion engine (1) is subjected to denitration and then is sent to the hot primary air pipeline after being boosted by the booster fan (4), a flue gas baffle door (5) and a flue gas adjusting air door (6) are arranged on the pipeline between the booster fan (4) and the hot primary air pipeline, the outlet end of the smoke baffle door (5) is connected with the inlet end of a smoke adjusting air door (6), the flue gas baffle door (5) is a shutoff door for isolated maintenance, the flue gas adjusting damper (6) is an adjusting damper for adjusting the amount of flue gas of the internal combustion engine entering the coal mill (7), the flue gas adjusting air door (6) is used for controlling the amount of flue gas entering the coal mill (7), and the hot primary air pipeline is connected with the coal mill (7).

2. The system of claim 1 for replacing the coal mill hot primary air with the flue gas discharged from the internal combustion engine, wherein: the hot primary air pipeline of the coal mill (7) is connected with an air preheater (8), and the air preheater (8) is respectively connected with a primary fan (9) and a blower (10).

3. The system of claim 2, wherein the system is characterized in that the system is arranged in a manner that flue gas discharged by the internal combustion engine replaces hot primary air of a coal mill of a coal-fired unit: the coal mill (7) and the air preheater (8) are respectively connected with the combustor (11) through pipelines.

4. The system of claim 1 for replacing the coal mill hot primary air with the flue gas discharged from the internal combustion engine, wherein: the hot primary air pipeline of the coal mill (7) is connected with a sealing fan (12) through a pipeline, the sealing fan (12) is respectively connected with a coal feeder (13) and the coal mill (7), and the coal feeder (13) is connected with the coal mill (7).

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