[Boutique] Thermal Power Plant Internship Report

Part 1: Thermal Power Plant Internship Report

Internship purpose

A few days of internships are both intense and fresh, because the units we visit are the places we will work in the future. Through the internship, we personally experienced the status of the work in the future, as well as the objects of the work to be carried out after work and the knowledge used. This not only stimulated my enthusiasm for the course, but also promoted our ability to use our knowledge constantly, recognizing Insufficient learning in the classroom. In my opinion, the internship has the following advantages:

First, understanding the internship can cultivate our ability to think comprehensively. To work properly in a power system, there are many factors to consider. For example, the tower supporting the transportation line is divided into a pull type, an upright type, a tensile type, and a span type, in order to adapt to different environments. Insulators and fittings are indispensable for transportation lines, in order to eliminate the effects of gravity and wind.

Second, understanding internships can foster our ability to think and solve problems flexibly. The input high voltage line of the substation visited has to pass through three relays and two transformers. With three different gears, you can control the working status of the two transformers for inspection and maintenance.

Third, internship training, we are strong in reading and practicing. Through internships, we learned more about how our professional staff work. Although we don’t know much about our expertise, we have a sense of what we have to do in the future. Understanding, this is more conducive to the study of theories in the future, and the perceptual knowledge rises to rational understanding.

Internship Content

Water injection station

I used to hear that underground oil was injected into the ground. However, before I visited the Xinsi Water Injection Station, I didn’t think that there was so much knowledge about water injection. What made me unbelievable was that the water injection also required uncontaminated water. The measure of using water injection wells to inject water into the oil layer to supplement and maintain the pressure of the reservoir is called water injection. After the oilfield is put into development, as the mining time increases, the energy of the oil layer itself will be continuously consumed, causing the pressure of the oil layer to continuously decrease, the underground crude oil will be degassed a lot, the production of the oil well will be greatly reduced, and even the production will stop spraying, resulting in a large number of underground residues. The oil can't be harvested. In order to make up for the underground deficit caused by the recovery of crude oil, to maintain or increase the pressure of the reservoir, and to achieve high yield and stable production of the oilfield, it is necessary to inject water into the oilfield. The function of the water injection station is to send the water supply system or the various low-pressure waters that meet the water quality requirements of the water injection to the high-pressure water required for oilfield development through the pump, and then send them to the water injection trunk line through the high-pressure valve group, and then send them through the water distribution room. Inject the oil well into the injection well. Generally, the source of water for oilfield water injection stations is generally water after refinery refinery and water from nearby rivers. The former generally needs to be purified to be transported to the major oil fields for injection into the ground, while the latter can be directly injected into the ground. The water injection station mainly consists of a water storage tank, a water supply pipe network, a water injection pump house, a pump unit, a high and low pressure water valve, and a power distribution, lubrication system and cooling water system. The water injection method is the injection and production system, which refers to the position of the water injection well in the reservoir and the arrangement relationship between the water injection well and the production well. The following water injection methods can be selected according to the characteristics of the oil field: edge water injection, which is divided into the outer water injection, There are three kinds of water injection on the edge and water injection in the edge; water injection for cutting; water injection in area, water injection by five points method, water injection by seven points method, water injection by seven points method, water injection by four points method and water injection by nine points method.

Substation and power supply training center

Our internship time is only a short five days, and the internship time in the substation has reached a long time. The internship in the power supply training center also took half a day. It can be seen that the understanding of electric power is important to our electrical majors. Sex.

A substation is a place in the power system that transforms, concentrates, and distributes the voltage and current of electrical energy. The power generated by the power station generally does not exceed one or two kilovolts. If it is directly transported over long distances, the line current will be large, which will cause a large loss of power on the line, uneconomical, and the line transmission power is very low. So use a transformer to raise the voltage to tens of thousands of volts or even hundreds of thousands of volts to reduce the line current. In order to connect power lines of different distances and powers into the grid to increase overall security, multiple substations are needed to match different levels of lines. Similarly, after the high-voltage power is delivered to the destination, in order to meet the needs of different users, it needs to be stepped down to several levels such as 10kV, 6kV, and 400V. Therefore, a lot of substations are needed in actual application. The role of the substation can be briefly summarized as five points: transforming the voltage level, collecting the current, distributing the electric energy, controlling the flow of the electric energy, and adjusting the voltage. In order to ensure the quality of electrical energy and the safety of equipment, voltage regulation, power flow control, and protection of transmission and distribution lines and major electrical equipment are also required in the substation. The substation consists of main wiring, main transformer, high and low voltage power distribution equipment, relay protection and control system, electrical and DC systems, telecontrol and communication systems, necessary reactive power compensation devices and main control room. Among them, the main wiring, main transformer, high and low voltage power distribution devices are primary systems; relay protection and control systems, DC systems, telecontrol and communication systems are secondary systems. The main wiring is the most important part of the substation. It determines the function, operating quality, maintenance conditions and power supply reliability of the substation. It is generally divided into several basic forms such as single busbar, double busbar, one and a half circuit breaker wiring and ring wiring.

The main wiring of the Shengli Oilfield Substation we visited is a single busbar segmentation structure. The main transformer is the most important equipment of the substation, and its performance and configuration directly affect the advancement, economy and reliability of the substation. The main transformer of the substation usually uses three-phase transformer. In addition, there are specific requirements for other equipment selection and site selection and overall layout of the substation. Substation relay protection sub-system protection and component protection two categories. The control methods of substations are generally divided into two categories: direct control and selective control. The former refers to the one-to-one button control. For the control substation, if the direct control mode is adopted, the number of control panels is too large, and the control monitoring surface is too large to meet the operation requirements. In this case, the selection control method is adopted. The selection and control method has the advantages of large control capacity, centralized control, and small control panel footprint; the disadvantage is that the intuitiveness is poor and there are many intermediate conversion links.

The substation introduces two high-voltage power supplies, which are controlled by three-way relays, so that the high-voltage power can be input through different standby devices, so that maintenance can be performed in the event of a fault. After the input voltage is transformed, the voltage is reduced from 110kv to 10kv. The transformer is the core equipment of the substation. The substation control room is equipped with control equipment, which controls all the equipment and equipment, as well as advanced alarm functions. At present, most of the substations use sulfur hexafluoride gas as the insulating medium. The substation is also equipped with lightning protection equipment, mainly including lightning rods and lightning arresters. The lightning rod is to prevent the substation from being subjected to direct lightning strikes to discharge the lightning to itself and to introduce lightning current into the earth. When lightning strikes on a line near a substation, lightning waves enter the substation along the wire, creating an overvoltage. In addition, circuit breaker operation and the like can also cause overvoltage. The function of the arrester is that when the overvoltage exceeds a certain limit, the automatic ground discharge reduces the voltage protection device and then automatically extinguishes the arc automatically to ensure the normal operation of the system.

The Power Supply Training Center is a place to train professionals in power. The training center we visited has trained many outstanding talents in power. Internship at the Power Training Center is a recognition of the basic skills that a senior electrician must possess. We visited the examination room in person and deeply felt the atmosphere of the school. The final safety ambulance has benefited us a lot. The advanced simulated human ambulance system gives us a preliminary understanding of the steps of electric shock ambulance.

Article 2: Thermal Power Plant Internship Report

In the thermal power plant, the boiler is burned, the chemical energy of the fuel is converted into heat energy conversion process, and the boiler unit's product is high temperature and high pressure steam. The energy conversion in a boiler unit involves three processes: the combustion process of the fuel, the heat transfer process, and the vaporization process of the water. The oxygen in the fuel and air is mixed in the boiler combustion chamber, oxidized and burned to generate high-temperature flue gas, and the process is burned.

I. Internship arrangements

On the afternoon of August 29th, I came to the XxXx International Xx Power Plant for a one-week internship.

On the morning of the 30th, the education of safety rules.

On the afternoon of the 30th, the master of the power plant gave the education of the Xx power plant production process.

On the 31st and the 1st, they were internships in the thermal workshop.

On the morning of the 2nd, I visited the furnace and visited the electrical in the afternoon.

On the morning of the 3rd, I visited the coal handling system and in the afternoon I visited the pump house in the chemical workshop.

Second, the internship content

1. Overall understanding of Xx power plants

The Xx Power Plant, a large state-owned enterprise, is affiliated to Beijing Xx Power Generation Co., Ltd., located in Kaiping District, Xx City, Hebei Province. It was built in December 1973 and was constructed in four phases. In October 1987, eight units were completed and put into operation. The capacity is 1550 MW. It has two 125 MW units, two 250 MW units and four 200 MW units.

2.Xx power plant production process

A thermal power plant is a plant that produces electricity from the chemical energy of coal, oil, natural gas, etc., that is, the chemical energy of the fuel → the thermal potential of steam → mechanical energy → electrical energy. In a boiler, the chemical energy of the fuel is converted into the thermal energy of the steam; in the steam turbine, the thermal energy of the steam is converted into the mechanical energy of the rotation of the wheel; in the generator, the mechanical energy is converted into electrical energy. Furnace, machine and electricity are the main equipments in thermal power plants, also known as the three mainframes. A device that works in conjunction with the three mainframes is called an auxiliary device. The host and auxiliary machines and their connected pipes and lines are called systems. The main systems of thermal power plants are combustion systems, soda systems, electrical systems, etc.

Raw coal for raw materials in thermal power plants. The raw coal is transported by train to the coal storage yard of the power plant, and then transported to the coal hopper by the coal conveyor belt. The raw coal is dropped from the coal and sent to the coal mill by the coal feeder to be ground into coal powder, and hot air is sent to dry and transport the coal powder. After the pulverized coal air mixture is separated by the separator, the qualified pulverized coal powder discharging machine is sent to the powder conveying pipe, and the burner is injected into the furnace of the boiler for combustion. The hot air required for fuel combustion is heated by the air blower into the air preheater of the boiler. The preheated hot air is sent to the coal mill for drying and powder feeding, and the other is directly led to the burner furnace. . The high-temperature flue gas generated by the combustion, under the action of the induced draft fan, first flows through the inverted U-shaped flue of the boiler through the furnace, the water wall tube, the superheater, the economizer, the air preheater, and the flue gas. The heat is transferred to the working air, and it becomes a low-temperature flue gas. The flue gas purified by the dust collector is extracted by the induced draft fan and discharged into the atmosphere through the chimney. If the power plant burns high-sulfur coal, the flue gas is discharged into the atmosphere after being purified by the desulfurization device. The ash generated after the combustion of coal, the large ash will be separated from the gas stream by its own weight, settled to the solid slag in the cold ash hopper at the bottom of the furnace, and finally discharged into the ash slag by the slag discharging device, and then pumped by the ash slag. Ash yard.

The fine ash particles are taken away with the flue gas and sent to the ash ditch after separation by the dust collector. The boiler feed water is preheated to near saturation temperature, and then heated to saturated steam by the heated surface of the evaporator, and the reheater is heated to superheated steam, which is also called main steam. The process completes the transportation and combustion of fuel, the generation of fuel and the discharge of steam. The main steam main steam pipe of the boiler superheated gas expands work, and the turbine is rushed to generate electricity. The exhaust steam discharged from the steam turbine is discharged into the condenser and is condensed and cooled into water. This condensed water is called main condensate. The main condensate condensate pump is sent to the low-pressure heater, and the steam turbine extracts the steam and then deaerator, and removes the gas dissolved in the water by heating. After the chemical workshop, the make-up water and the main condensate sink in the water tank of the deaerator, the feed water of the boiler, and then the feed pump is boosted and sent to the high-pressure heater, and the steam extracted by the high-pressure turbine is heated and then sent to the boiler, thereby Working fluid thermodynamic cycle. The circulating water pump sends the cooling water to the condenser, absorbs the heat of the exhausted air and returns to the river, which opens the circulating cooling water system. In a water-deficient area or a power plant far from the river. A circulating water cooling device such as a high-performance cooling tower or a fountain is required to close the circulating cooling water system.

The process is the process of converting the thermal energy of steam into mechanical energy, electrical energy, and boiler feed water supply. A thermal power plant is an energy conversion plant consisting of furnaces, machines, and electricity, and their respective auxiliary equipment and systems.

3.XX power plant equipment awareness

In the Xx power plant, the common boiler is recognized. In the thermal power plant, the boiler is burned, the chemical energy of the fuel is converted into heat energy conversion process, and the boiler unit's product is high temperature and high pressure steam. The energy conversion in a boiler unit involves three processes: the combustion process of the fuel, the heat transfer process, and the vaporization process of the water. The fuel and the oxygen in the air are mixed in the boiler combustion chamber, oxidized and burned to generate high-temperature flue gas, and the process is burned. The heat-receiving surfaces of the high-temperature flue gas boiler transfer heat, and the heat energy is transferred to the boiler's working fluid, water. After the water absorbs heat, it vaporizes into saturated steam, and the saturated steam absorbs heat to become high-temperature superheated steam, which transfers heat and vaporizes the water. About the water used in the boiler, the teacher introduced it, it is extremely pure. The Robust pure water is said to have undergone 27 layers of filtration, but in the face of boiler water is only pediatrics, the boiler water is much purer than it. During the internship, it was recognized that the feed water of the boiler flowed from bottom to top, and after heating, the steam drum was then lowered to the lower header of the water wall, and then the water wall was cooled. The water turns into a steam-steam mixture in the water wall. The soda-water mixture separates in the drum and the water remains in the next cycle of the package. The boilers use coal. It is the raw material of thermal power plants. In the Xx power plant, the master took a tour of the coal yard, and the power plant also had requirements for coal. The power plant uses a pulverized coal fire boiler. The reason is that the pulverized coal has good fluidity and can be burned. Before use, hot air is injected into the furnace and mixed with air, and suspended combustion in the furnace. The brother of Xx Power Plant said that the fineness of pulverized coal is large, mainly burning. Today's environmental problems have seriously hindered the development of human beings. In thermal power plants, the exhaust gas must undergo desulfurization before it can be discharged. The smoke in the chimney of the Xx power plant is desulfurized.

Third, the understanding summary

A thermal power plant is a very large whole consisting of many thermal and electrical equipment. In a sense, thermal equipment is more, more and more prone to failures and accidents. The relationship between heat and electricity is Close. Anyone who is engaged in thermal work is a certain knowledge of the heat. The internship has a clear understanding of the safe and economic operation of the power plant and a serious work style. In the future work, it should be organized, disciplined, team spirit and other good qualities.

Part 3: Thermal Power Plant Internship Report

The time at the university was very happy, and now the junior year’s learning journey is almost over, and the university’s second internship is coming. This internship we went to XXX Power Plant Co., Ltd. and Guangzhou Huangpu Power Plant. There are not many internship opportunities at the university, it is hard to get, and it is very important. Opportunities always have to be grasped by themselves, grasp the internship opportunities, pay attention to the internships, be good at thinking in the internships, and combine the knowledge learned with the actual ones to enhance their own knowledge and broaden their horizons. Learning ability.

Just like the first internship, I was fully prepared for the internship, prepared the questions, and prepared to think. One week before the internship, I read a lot of books about thermal power plants in the library, and I also learned about hydropower and nuclear power. This preparation before the internship has benefited me a lot.

First, the purpose of the internship and tasks

Production practice is an important part of the thermal energy and power engineering professional teaching program, and is an important practical teaching link. It is carried out after the students have basically completed the professional basic courses and have passed the exercises of the practical teaching links such as “Metalworking Internship”, “Understanding Internship” and “Electrical and Electronic Technology Training”. It is a necessary supplement to classroom teaching and an extension of practical teaching. It is a process of implementing the principle of linking theory with practice and deepening understanding. It is also an important way for students to get in touch with and understand society during their studies. The best opportunity for workers to learn is also a preview of the actual work after graduation. It plays an important role in achieving professional training goals. In production internships, students should go deep into the production site, earnest internships, gain direct knowledge, and consolidate the theory they have learned. Its main teaching purposes are:

1. By participating in actual production work, flexibly using the theoretical knowledge already learned to solve practical problems, and cultivating students' ability to analyze and solve problems independently.

2. During the internship process, the students constantly learn the excellent quality of the workers and field technicians. The tree immediately studies the idea of ​​science and technology contributing to the modernization of the motherland.

3. Through the production internship of thermal power plants, the basic principles of the thermal process of the thermal power plant and the process flow of the entire power generation process should be mastered.

4. Through the production internship of thermal power plants, understand the power plant centralized control operation system and transmission and distribution methods in the thermal power generation process.

5. Through the production internships of thermal power plants, understand the basic knowledge and capabilities necessary for electric power production, power installation and power design.

6. Through the production internship of the thermal power plant, collect technical data related to the major and carefully analyze it to prepare for the follow-up professional course study and graduation design.

Second, the total understanding

Basic production process of thermal power plants

See the diagram below for the power generation process of the thermal power plant:

The olefin coal is sent to the original coal hopper by a belt coal conveyor installed in the sloping shed, and then sent to the coal pulverizer to make pulverized coal, which is sent to the boiler for combustion through the powder discharging fan. The air required for the combustion of pulverized coal is sent by a blower to an air preheater arranged at the end of the boiler. A part of the hot air enters the coal mill through the powder exhaust fan to heat and dry the coal powder, and enters the furnace together with the coal powder through the burner; the other part directly enters the furnace through the burner to participate in the combustion. Coal powder converts chemical energy into heat energy when the furnace is burned, releasing a large amount of heat. The high-temperature flue gas generated by the combustion passes through the superheater, reheater, economizer and air preheater arranged in the horizontal flue and the tail flue of the top of the furnace, and finally discharged to the dust removal equipment, the induced draft fan and the chimney. At high altitudes. The ash in the combustion and the incompletely burned carbon particles will fall into the slag bucket at the bottom of the furnace, and will fall into the trench together with the fine ash removed from the dust collector and be washed away by the high pressure water, and finally sent to the ash field by the mortar pump.

The feed water as the working fluid is boosted by the feed water pump and sent to the boiler economizer through the high pressure heater of the steam turbine. The feed water absorbs the heat of the flue gas in the tail flue gas in the economizer and then enters the steam drum, and then is disposed outside the furnace wall. The descending pipe passes through the lower tank and enters the water wall disposed on the wall of the furnace to absorb the radiant heat when the pulverized coal is burned. When the feed water flows through the water wall, a part of the water evaporates into steam and flows into the steam drum in the form of a soda mixture. After the soda-water mixture is separated in the foreign devil's bag, the steam enters the superheater for overheating to form superheated steam. The superheated steam is sent to the steam turbine for work by the main steam pipe. For the intermediate reheating tear turbine, the superheated tears first enter the high pressure cylinder for work, and then the steam discharged from the high pressure cylinder is sent back to the boiler reheater for further work. Overheating, after the temperature is raised to the same temperature as the new steam, it is sent to the steam turbine, and the low-pressure cylinder continues to expand and work to drive the generator to generate electricity. The general steam that has worked in the steam turbine is finally discharged into the condenser and condensed into water, and flows into the hot well at the bottom of the condenser. The condensate pump and the low-pressure heating tears are sent to the deaerator to remove oxygen and fall into the water tank. Re-energized by the feed pump and sent to the boiler to absorb heat and tears for recycling.

Although there are many types of thermal power plants, the basic processes are the same from the perspective of energy conversion, namely: chemical energy of fuel → thermal energy → mechanical energy → electrical energy.

The major components of a thermal power plant:

A thermal power plant is a plant that uses the chemical energy of coal, oil, natural gas, or other fuels to produce electricity. The main components are:

Boilers and ancillary equipment ensure that the chemical energy of the fuel is converted into heat. Turbines and ancillary equipment ensure that thermal energy becomes mechanical energy. Generators and exciters ensure that mechanical energy becomes electrical energy. 4) The main transformer, which boosts the electric energy to high-voltage electricity to the transmission line.

First, the fuel system

China's coal resources are abundant, so the fuel of China's thermal power plants is mainly coal. The coal-fired power of the power plant is very large, so the thermal power plant has a coal-fired transportation system with a large volume of transportation and a high degree of mechanization automation.

The coal combustion of Xinhui Shuangshui Power Plant Co., Ltd. and Guangzhou Huangpu Power Plant are all shipped by ship, and the coal is transported to the terminal of the power plant and then discharged to the coal yard.

Coal handling system and coal yard equipment: Unloading coal: The equipment has loading and unloading bridges, door grabs and bridge grabs. All the coal is taken out and placed in the unloading equipment. Coal yard: In order to meet the needs of safe production of power plants, set up coal yards and reserve a certain amount of coal. Under the temporary interruption of external coal transportation, it can ensure the normal production of power plants; it can also be used for coal burning and coal transportation. It acts as a buffer when it is not balanced; it can also be used as a pre-matching and mixing site for different coal types. , coal: the main role is to complete the transportation, crushing, screening, sub-measurement of coal. Equipment includes: belt conveyor, coal screen, coal crusher, iron remover, wood block equipment, electronic belt scale and so on.

Milling System

The milling system is divided into a direct blowing type pulverizing system and an intermediate storage type pulverizing system. The direct-blowing pulverizing system is a pulverized coal pulverized by a coal mill directly blown into the furnace. The intermediate storage type powder milling system is that the coal powder milled by the coal mill is first stored in the coal powder bin, and then according to the combustion requirements of the boiler, the coal powder is fed from the coal powder bin to the powder machine | the primary air pipe is sent to the boiler combustion chamber Burning milling system.

Preparation of pulverized coal: The equipment is a coal mill. The coal mill can be divided into low speed coal mill, medium speed coal mill and high speed coal mill according to the rotation speed. The main working principle is: raw coal and air enter the body of the coal mill. When the cylinder rotates, the wave-type lining puts the steel ball to a certain height, then falls, and the coal is hit by the steel ball in the cylinder. It is also squeezed and milled by steel balls and eventually broken into pulverized coal. The air acts as a dry-drying effect on the raw coal and coal powder, and at the same time, the coal powder is taken out of the coal mill through the outlet hopper.

Third, the boiler

The boiler is one of the three main equipments of a thermal power plant. Its role is to turn water into high temperature and high pressure steam. A boiler is a summing device for three processes of fuel combustion, heat transfer, and vaporization of water.

The boilers of Xinhui Shuangshui Power Plant Co., Ltd. and Guangzhou Huangpu Power Plant, which were visited during the internship, were respectively circulating fluidized bed boilers and DC boilers.

Circulating fluidized bed boiler: The fixed grate furnace is to place coal on the grate, and air is introduced from below the grate to burn the coal seam. In the circulating fluidized bed boiler, the speed of feeding the air below the grate of the grate furnace is increased, so that the coal particles on the grate are blown up and boiled and suspended. At the same time, at the outlet of the furnace, the high-temperature flue gas is dedusted, and the collected fly ash containing more carbon is returned to the furnace and then burned. The boiler burned in this way is called a circulating fluidized bed boiler.

DC boiler: refers to the boiler that relies on the pressure of the feed water pump to make the feed water pass through the economizer, the evaporation heating surface, the superheater and all of the superheated steam.

Composition and arrangement of boiler equipment

The boiler equipment consists of two parts: the boiler body and auxiliary equipment. These devices were heard during our internship.

1 boiler body part of the steam water system 1 economizer. The economizer is arranged in a region where the flue temperature of the flue of the boiler is low. It consists of a number of rows of serpentine tubes, the inside of which flows water from the feed water pump, absorbs the heat in the flue gas, heats the water to a saturated temperature and then feeds it into the steam drum. 2 water wall. The water wall is a row of tubes arranged vertically inside the wall of the furnace. It absorbs the radiant heat released by the combustion of the fuel, heats the saturated water inside it, and turns it into a mixture of steam and water to protect the furnace wall from being burned out, preventing the slagging of the furnace wall and avoiding the slag on the furnace wall. erosion. 3 steam drums. The inside is equipped with a steam separator. In the soda circulation, it plays a central role. It has a large volume, which is both water and steam. 4 headers. There are upper and lower headers. 5 drop tube. It is the passage for the steam drum to supply water to the header below the water wall, and is arranged outside the furnace wall, free from heat, and does not generate steam 6 superheater. It is a device that raises the steam temperature and the internal energy of the steam, and is composed of a serpentine tube row. It is placed in the flue where the smoke temperature is higher after the exit of the furnace. 7 Reheater. After the steam is working in the steam turbine, the pressure and temperature are greatly reduced, and the heat is sent to the reheater to increase its temperature and its internal energy, and then return to the low pressure section of the steam turbine to work, thereby improving the thermal efficiency. It is generally placed across the high temperature zone of the flue with the superheater.

Combustion system 1 air preheater. It is a device that heats the air. It is arranged in the part of the flue where the temperature of the flue is low, which can further reduce the flue gas temperature, feed heat loss and improve the boiler thermal efficiency. 2 burner. It is the combustion equipment of the pulverized coal boiler. 3 Furnace and flue. The furnace wall is a large space surrounded by water-cooled wall pipes. There is a furnace wall outside the water-cooled wall pipe, and the furnace wall separates the entire boiler from the outside. The flue is a flue gas passage surrounded by a furnace wall, and the flue gas at the exit of the furnace is introduced into the precipitator as required.

2 boiler auxiliary equipment

1 blower 2 induced draft fan 3 row powder machine 4 to powder machine 5 fine powder separator 6 coal powder warehouse 7 powder machine 8 spiral powder feeder

Fourth, the steam turbine

This semester we just learned the course of steam turbine principle, and the internship made us feel the steam turbine more intuitively. The theory is not the same as the reality. During the internship, I compared the knowledge gained in class with the explanations of the power plant masters, and further understood the steam turbine.

The steam turbine is a rotary thermal power machine with steam as the working fluid. The main purpose of the steam turbine is as the prime mover for power generation. The steam turbine must be combined with boilers, generators, and mechanical equipment such as condensers, heaters, pumps, etc. to work together. The steam with a certain pressure and temperature comes from the boiler, enters the steam turbine through the main gas valve and the regulating gas valve, and flows through a series of annularly mounted nozzle grids and moving blade cascades to expand work, transforming its thermal energy into pushing the turbine rotor to rotate. The mechanical work is done by the coupling driving the generator. In a thermal power plant, the steam after the expansion work is introduced into the condenser by the exhaust portion of the turbine, and the cooling water is released and condensed. The condensed water is then pumped to the heater for heating and then used as boiler feed water to circulate.

The steam turbine includes a stationary portion and a rotating portion. The stationary part includes cylinders, nozzles and partitions, steam seals, bearings, and the like. The rotor consists of a large shaft, an impeller, blades on the impeller, and other components that are an important part of the turbine.

The figure below shows the structure of the steam turbine:

Turbines are divided into two categories according to their working principles: impulsive steam turbines and reaction steam turbines. The nozzle grid and its matched moving blade cascade form the most basic working unit "stage" in the steam turbine, and the different stages are sequentially connected in series to form a multi-stage steam turbine. The steam is converted in different ways in the stage to form steam turbines of different working principles, namely impulsive steam turbines and reaction steam turbines.

Impulse turbine. There is mainly an impulsive stage composition in which steam is substantially expanded in the nozzle grid, with only a small amount of expansion in the cascade.

Reaction turbine. There are mainly reaction stages, and steam has a moderate expansion in the turbine's stationary blade cascade and moving blade cascade.

Steam turbine auxiliary equipment

The auxiliary equipment of the steam turbine includes a condenser, a regenerative heater, a deaerator, a feed water pump, and a condensate pump.

Condenser: Its function is to cool the turbine exhaust and condense it into water to establish and maintain a high vacuum at the turbine exhaust.

Regenerative heater: The regenerative heater is set to reduce the loss of cold source and improve efficiency. Its function is to use the steam that is extracted from some intermediate stages of the steam turbine to heat the main condensate and the boiler feed water. The regenerative heater has a high-pressure heater and a low-pressure heater, and has the same structure.

Deaerator: Its working principle is: under a certain pressure, the higher the temperature of water, the smaller the solubility of gas, and the greater the solubility of gas. At the same time, the higher the partial pressure of the gas on the water surface, the greater the solubility, and vice versa, the lower the solubility.

Five, the generator

Turbine generator

Its basic working principle: According to the law of electromagnetic induction, the wire cutting magnetic line induces the electromotive force. The most basic components of a generator are: the stator and the rotor.

The stator consists of an iron core, a stator winding, a base, an end cover and a bearing.

The rotor is mainly composed of a rotor core, a field winding, a guard ring and a fan.

Six, two power plants comparison

1. The boiler of XXX Power Plant Co., Ltd. uses a circulating fluidized bed boiler; the boiler of Guangzhou Huangpu Power Plant uses a direct current boiler. The DC boiler has no steam drum part and can be used for all pressures. The water wall is freely arranged and the reaction is fast.

2. XXX Power Plant seeks cluster development and introduces papermaking base; Huangpu Power Plant is a key power plant in Guangzhou and has an important position.

3. The employees of XXXX Power Plant require all-round development. This requires employees to continue training after entering the factory. This increases the training cost, but improves the quality of employees and reduces the burden on users.

Internship harvest and experience:

The two-week internship is over soon, and although it is not long, it has benefited a lot for our students. Through this internship, I have generally recognized the thermal power plant and have a systematic and comprehensive understanding of the basic structure, working principle and performance of the main production equipment of the thermal power plant. The power plant has a complicated structure and a large number of equipments. It is so little to know the knowledge of the power plant. At school, we all seem to know what the boiler is, but when the power plant faces a tens of meters high boiler, I don't understand it. I see the pipes. It seems that the power plant is built with pipes. I don’t understand how those pipes are arranged. Learning is endless. If you know your own deficiencies, you will make up for it. If you know your ignorance, you will continue to study. Now you should study hard at school and you will come to the society to continue your studies. This internship gives me a deeper understanding of my major and provides the necessary perceptual knowledge and basic knowledge for the follow-up of professional courses. Today's technology is changing with each passing day. If you want to achieve something, you must continue to learn, constantly update your knowledge, broaden your knowledge, apply what you have learned, and apply knowledge to practice.