Scraper reclaimer

1. The bucket wheel stacker reclaimer is the main equipment of large-scale loose material stacker reclaimer, which is widely used in coal, mines, ports and other places. Due to the complex working conditions and the characteristics of large particle size and high speed in material transportation, the impact of materials is large. Therefore, wear-resistant lining plates should be set on the washout surface of materials such as coal chute and coal scuttle to prevent the wear and premature damage of metal structures. The wear-resistant lining plates mainly include stainless steel lining plate, ceramic lining plate and wear-resistant composite lining plate, According to the past experience, our company summarized as follows:
selection and performance comparison of wear-resistant lining plate
at present, there are many kinds of wear-resistant lining plate proced in China, but the performance is uneven. Based on years of practical experience and user feedback, the advantages, disadvantages and performance of six kinds of commonly used wear-resistant liners at the coal drop pipe and coal hopper of Bucket Wheel Stacker Reclaimer are roughly compared according to the selection principle of wear resistance, easy replacement and economy
the stainless steel liner has high water absorption and coefficient of thermal expansion, impact resistance, smooth surface, which is concive to material flow. It is a popular proct in bulk machinery instry. But in the practical application, because of its high price, it is difficult to be competitive in the project budget, and according to the user feedback information, in addition to the impact resistance performance has certain advantages over other procts, the overall cost performance is not high, and the actual application effect is not very superior
ceramic corunm rubber lining ceramic corunm rubber lining is a kind of lining formed by inlaying ultra-high wear-resistant corunm ceramic pieces in special rubber, and then curing with high-strength vulcanizing adhesive and steel plate under heating and pressure. With impact resistance, ultra-high wear resistance, anti-static, anti-corrosion performance, and easy installation. It is widely used in the transportation and batching system of bulk machinery instry, such as the center coal pipe and hopper of bucket wheel stacker reclaimer. The wear-resistant ceramic sheet in ceramic corunm rubber lining board is made of special ceramics with high wear resistance and high toughness. It is made of 95% Al2O3 and various wear-resistant materials. It is formed by 100 tons dry pressing. It has the characteristics of high density, high toughness and wear resistance. The wear resistance of wear-resistant ceramics is 266 times that of manganese steel and 171.5 times that of high chromium cast iron. The high temperature and anti-aging special adhesive can be molated according to the actual use requirements. The lining plate can be twisted and cut, which is suitable for installation on various special-shaped equipment, and has the characteristics of water resistance, weak acid-base resistance, etc. However, the process of ceramic corunm rubber lining is more complex than other lining, which requires higher ambient temperature and must be limited to the ambient temperature below 100 ℃. The price is relatively high, and the user's practical application is less
cast stone liner cast stone liner is a traditional wear-resistant liner with a long history and low price. It has the advantages of slightly better impact performance than microcrystalline liner, wear resistance, low water absorption and thermal expansion coefficient, simple construction, good material fluidity and high cost performance. But the lining plate is thick, and the surface and interior are not uniform. Due to many manufacturers, the price difference is also relatively large. Some manufacturers offer very low prices, in fact, they are shoddy bonding materials, resulting in lining is very easy to fall off. The difference of solid cast stone liner is big, so it should be chosen carefully
bimetallic wear-resistant composite steel plate
bimetallic wear-resistant composite steel plate is formed on ordinary steel plate, heat-resistant steel plate and stainless steel plate, and the main wear-resistant layer is Cr7C3 carbide with volume fraction of more than 50%. It has the properties of high wear resistance, impact resistance, deformability and weldability. It can be directly processed like steel plate, such as curling deformation, cutting and drilling. Its service life can be increased by 5-10 times. The processed liner can fully meet the requirements of high wear resistance at the drop pipe and coal hopper of bucket wheel stacker reclaimer. Compared with many wear-resistant lining plates, bimetal wear-resistant composite steel plate has its unique characteristics: (1) high wear resistance. Because of the high content of carbon and chromium in the alloy layer and the vertical distribution of carbide wear square phase, the wear resistance of the alloy layer is more than twice that of the cast alloy 2) Good impact resistance. The wear-resistant layer resists the wear of the wear medium, and the substrate bears the load of the medium, which fully embodies the advantages of bimetal and has good impact resistance 3) Good heat resistance. The wear-resistant layer of bimetal wear-resistant composite steel plate can be used under the condition of less than 600 ℃ 4) Good corrosion resistance. The alloy layer of wear-resistant composite steel plate contains a high percentage of metal chromium, so it has certain rust and corrosion resistance 5) High price performance ratio. Although the manufacturing cost of wear-resistant composite steel plate is high, its service life is also increased several times, which greatly reces the maintenance cost and shutdown loss. Its price performance ratio is about 2 ~ 4 times higher than that of ordinary materials 6) Convenient processing performance. Wear resistant composite steel plate can be cut, leveled, drilled, bent and curled
3 conclusion
practice has proved that when selecting the wear-resistant liner for the coal drop pipe and coal hopper of bucket wheel stacker reclaimer, not only the wear resistance and service life of the selected materials should be considered, but also the price, cost performance and other requirements should be considered. The enterprise should choose the wear-resistant liner reasonably according to the actual working condition and capital situation.

3.

Stacker reclaimer, also known as bucket wheel stacker reclaimer, stacker reclaimer and reclaimer, is a new type of high efficiency continuous loading and unloading machinery. Bucket wheel stacker reclaimer (stacker reclaimer) is a new type of high-efficiency continuous loading and unloading machine, which is mainly used in bulk cargo specialized wharf, steel plant, etc

after proction and practice, the performance and parameters of stacker reclaimer of various specifications and models have been serialized and standardized in both strip yard and circular yard. Users can choose the stacker reclaimer suitable for themselves according to the work nature and purpose of the Department

extended data:

in recent years, e to the strengthening of environmental protection awareness, for example, the chemical instry and cement instry often adopt closed circular stockyard stacking and reclaiming operation to rece the pollution of st to the surrounding environment, which not only occupies less area, but also has high utilization rate of stockyard space, and can realize all automatic operation, which is economical and practical, Therefore, the circular stockyard has become the development trend of stacker reclaimer and the leading proct of stockyard, and has a broad development prospect

At present, China can design and manufacture rocker type bucket wheel stacker reclaimer, stacker reclaimer; Portal stacker reclaimer, portal mixer reclaimer, bridge type double bucket wheel mixer reclaimer, rotary bridge type double bucket wheel reclaimer, circular yard stacker reclaimer, scraper type mixer reclaimer, etc

4. Is the scraper reclaimer used in cement plant? I have seen cj108, cj109 two models. Proction of this kind of mechanical general steel plate on the line, scraper blade teeth part slightly higher hardness, wear resistance, with 16Mn

5. The protective measures of bag st collector include temperature monitoring, gas analyzer, anti-static and explosion-proof valve
2. The main function of accumulator is to rece damping vibration and maintain pressure
3. Our coal mill models are mpf1713, mpf2116, mpf1713, and mpf2116, with a design capacity of 20t / h and 40t / h respectively; When the material layer is 60-100 mm, it is absolutely not allowed to start the empty mill. If the material layer in the mill is too low, it should be considered to use the material distribution in the mill
4. When the vibration value of the mill reaches 4mm, a low alarm will be given, and the mill will stop when the vibration value is 6mm
5. When the low pressure of the thin oil station is less than 0.12mpa, the standby pump starts, and when the pressure is more than 0.40MPa, the standby pump stops running
6. Vertical mill has five functions: drying, crushing, grinding, powder selection and conveying
7. Before the roots blower starts, the outlet baffle is opened, and before the centrifugal blower starts, the outlet baffle is closed
8. The coal mill separator (viewed from the bottom to the top) is counter clockwise, which is the same as the rotation direction of the grinding plate
9. Bag st collection and cleaning methods can be divided into mechanical type and pulse injection type
10. There are three corresponding types of fan baffle: baffle opening and actuator, actuator and central control, central control and baffle opening
11. Three level inspection includes on-site inspection, central control inspection and technical point inspection
12. There are two main effects of lubricating oil on recer: lubrication and cooling
13. The cycle load rate refers to the ratio of the return powder to the finished proct of the separator
14. The excessive slag discharge of the main mill is related to the cyclone direction and wind speed of the nozzle ring
15. In order to prevent the damage of nitrogen accumulator bladder, there is a 3:1 ratio between the working pressure of hydraulic tension and the nitrogen precharge pressure
16. The accumulator mainly uses rigidity and flow resistance to keep pressure and buffer the impact force of grinding roller< There are two sealed fans in mpf1713 coal mill, one for grinding roller and the other for separator
18. The three air lock valves are divided into three channels, each of which is mainly used to cut off the material and control the feeding quantity and time; The second air lock is not in contact with materials; The third one starts to lock and unload
19. The spontaneous combustion of raw coal must have sufficient oxygen and ignition point
20. On the one hand, the three tensioning rods connect the hydraulic cylinder, on the other hand, they transmit grinding pressure
21. Inform the site to adjust the fuel injection amount according to the heating curve, so that the flame is lively and powerful, and there is no oil dripping down
22. Mpf1713 coal mill feed particle size ≤ 30mm, feed maximum moisture ≤ 20%
23. Before the start-up of mpf1713 coal mill, the temperature in the mill should be increased to 65 ℃ slowly ± 5 ℃ for 0-1.5 hours. [Note: ring cold grinding, i.e. the mill is shut down for more than 24 hours and then heated for 1-1.5 hours], there is no need to warm up ring hot grinding, and the temperature rises slowly when starting grinding
25. In the normal operation of the mill, the fineness of the pulverized coal can be adjusted by adjusting the speed of the separator and the wind speed in the mill
26. When the hot blast stove is used, start the main exhaust fan and keep the negative pressure of grinding less than - 100Pa to prevent the flame from extinguishing after ignition
27. The drying heat source of the coal mill comes from the kiln head cooler, and the temperature is about 300-400 ℃. In any case, the temperature of the air entering the mill shall not exceed 350 ℃; Generally, it is between 250 ℃ and 300 ℃
28. In case of sudden kiln shutdown, close all valves on the silo and fill the silo with nitrogen. When the kiln shutdown lasts for more than 24 hours, cover the pulverized coal silo with about 5 tons of raw meal powder
29. Performance and reasons of non pressure maintaining in coal mill tension station system
A: the tension station does not maintain pressure, which is characterized by frequent motor starting, large pressure fluctuation and hot oil tank. Causes: (1) the seal of cylinder head or piston rod of hydraulic cylinder is damaged, resulting in leakage 2) The accumulator pressure is low or the bag is damaged and the return valve is damaged 3) The direct relief valve on the tension cylinder is out of order and in overflow state 4) The pilot relief valve on the hydraulic station is out of order and in overflow state
30. The equipment should be kept clean and "four no" and "six no leakage" should be achieved. The "four no" refers to no ash, no debris, no looseness and no oil stain“ "Six no leakage" refers to no oil leakage, no water leakage, no air leakage, no electric leakage, no air leakage and no ash leakage
31. The maximum working pressure of the tension hydraulic system of the first stage coal mill is 11.5MPa, and the oil pressure required when the mill roll is raised is 4.0Mpa
32. The pressure rise of Roots blower is the difference between the exhaust pressure and the inlet pressure of the blower. The pressure gauge of Roots blower is usually installed with the air inlet and outlet of the blower to detect the operation condition of the blower. A bypass branch is set on the exhaust pipe of Roots blower, and the exhaust can be divided by opening the bypass valve, so as to rece the flow into the system. The bypass regulation is divided into two situations: venting and backflow
33. Briefly describe the function of accumulator 1) As an auxiliary power source (2) to maintain pressure and supplement leakage (3) to mitigate impact and absorb pressure pulsation
34. Analyze the reason why the pulse valve of bag st collection doesn't work and the solution
A: the reasons may be (1) power failure or ash leakage controller failure 2) There are impurities in the pulse valve 3) The solenoid valve coil is burnt out 4) The compressed air pressure is too low
Troubleshooting: (1) restore the power supply and repair the st removal controller 2) Clean pulse valve carefully 3) Replace the solenoid valve 4) Check the air system and compressor to ensure the normal pressure
35. Try to analyze the reasons for the large resistance of bag st collection operation and the elimination methods
A: the possible reasons are (1) condensation of flue gas, st paste bag 2) Pulse valve does not work 3) When the pulse valve works, the lift valve is not combined with the valve 4) The pressure of compressed air is too low 5) One or more lifts are off
elimination methods: (1) block the air leakage and increase the flue gas temperature 2) Cleaning or replacement 3) Check the lifting valve or ash cleaning controller 4) Check the air system and air compressor 5) Check the lift valve or ash cleaning controller
36. Analyze the cause of excessive differential pressure of the mill
answer: (1) the feeding control device is faulty and the feeding is too much 2) The nozzle ring of grinding plate is blocked 3) The air volume is small or unstable 4) The Separator turns to reverse height
37. What are the functions of coal mill sealing fan
answer: (1) it can block large materials 2) The clearance between the spindle and the seal can be small enough to form a certain sealing air pipe pressure, so as to avoid dirt entering the bearing
38. What are the functions of coal mill tension station
answer: (1) apply proper grinding pressure to the grinding roller to raise and lower the grinding roller
39. Analyze the cause and treatment of high temperature in oil tank of coal mill tension hydraulic station
answer: the reasons are: (1) the seal of the hydraulic cylinder is damaged, which makes the motor of the tension station open all the time 2) The set value of the upper limit pressure of the oil pump in the tension station is greater than the set pressure of the relief valve, so that the oil pump motor is always on 3) The cooling water valve is broken, resulting in untimely cooling
treatment methods: (1) check the hydraulic cylinder without pressure maintaining, and select the machine to replace the hydraulic cylinder assembly or seal 2) Reset the upper limit of pressure to make it less than the set pressure of relief valve 3) Check the cause of cooling water valve failure and deal with it accordingly
40. What is the function of accumulator
A: a large amount of oil supply in the short term; System pressure maintaining; Emergency energy; Ease the impact pressure; Absorb pulsating pressure
41. What is the main function of overflow valve of coal mill
A: in the throttling speed regulation system of the constant displacement pump, it is used to keep the pressure at the outlet of the hydraulic pump constant and overflow the excess oil back to the oil tank, which plays a role of constant pressure and overflow. It plays a safety role in the system and protects the system from overload
42. What is the function of directional valve in hydraulic system
A: the directional valve uses the relative motion between the valve core and the valve body to change the direction of oil flow, or to connect and close the oil circuit, so as to change the working state of the hydraulic system
43. What is the reason for the abnormal sound of Roots blower
answer: (1) the position of synchronous gear and rotor is out of alignment 2) The bearing is worn seriously (3) the pressure rise fluctuates greatly (4) the gear is damaged (5) the safety valve is started repeatedly (6) the check valve is damaged
44. The process flow is described as follows:
the raw coal entering the plant is unloaded by the ship unloader at the loading dock, piled by the 3104 stacker through the 3101 belt conveyor, homogenized, and then taken out by the 3107 side reclaimer through the 3108 belt conveyor, After the iron is removed by 3110 iron remover, it is sent to 3123 belt conveyor. It enters 3801 raw coal bunker through 3124 iron remover or scrapes raw coal through 2107 side arm reclaimer, and then enters 3801 raw coal bunker through 2119, 2120, 3121 and 3123 iron remover
the raw coal in the raw coal bunker passes through the bar valve at the bottom of the bunker and then falls into the 3 (4) 802 quantitative feeder. The 3 (4) 802 three-way air lock valve feeds the 3 (4) 804 coal mill's grinding plate, and moves to the edge of the grinding plate by centrifugal force on the rotating grinding plate. During the movement, it is pressed into fine powder by the grinding roller. At the edge of overflow, the hot air from the grate cooler is blown out from the nozzle ring to lift the overflow fine powder and dry it. The fine powder is brought into the upper separator of vertical mill with hot air and separated by separator. The coarse powder falls to the grinding plate through the hopper. The fine powder and waste gas enter into 3 (4) 832 bag st collector. The pulverized coal collected by bag st collector is discharged into 3 (4) 820 (2) kiln head pulverized coal bin and 3 (4) 820 (1) calciner pulverized coal bin through 3 (4) 818 rotary feeder, 3 (4) 817 screw conveyor and 3 (4) 817 pneumatic gate valve, Then, the air is supplied by 3 (4) 827 and 3 (4) 825 roots blowers and measured by fester scale, which is continuously sent to the kiln burner and calciner. In order to prevent the coal bunker and bag st collector from fire, the system is equipped with N2 filled fire extinguishing device, which respectively extinguishes the coal bunker and bag st collector. At the same time, the explosion-proof valve is set on the bag st collector, the outlet air pipe and the pulverized coal bin
45. When operating with the hot blast stove:
1) close the hot blast baffle of the cooler; 2) Open the baffle of hot blast stove and start the outlet equipment and integrated control cabinet; 3) Start the main exhaust fan and keep the grinding negative pressure less than - 100Pa to prevent flame extinction after ignition; 4) Inform the site to point the hot blast stove, adjust the oil flow of the hot blast stove, and keep the outlet temperature of the mill above 65 ℃
46. Preparation before start-up
1) inform the on-site inspection personnel to check before start-up, and confirm that the equipment in the system has safe operation conditions
2) check the lubrication of on-site equipment, check whether the oil quantity and temperature of the oil station of recer and hydraulic system are appropriate, and whether each lubrication point is filled with oil. If the oil temperature is too low, start the oil pump and heater on site for circulating heating, which should be carried out 3 hours before the mill starts
3) whether there are sundries and spontaneous combustion in the field equipment, whether the manhole door is sealed, whether there are people working around the equipment, whether there are foreign matters affecting the operation of the equipment, and whether the equipment is in good condition
47, alarm value:
1) recer Vibration > 5mm / S
2) the oil level of deceleration oil station is lower than the lower limit or higher than the upper limit alarm oil level
3) differential pressure of coarse filter in deceleration oil station △ P ≥ 0.08mpa
4) differential pressure of fine filter in deceleration oil station △ P ≥ 0.05Mpa
5) the oil temperature of deceleration oil station is less than 32 ℃
6) when the oil pressure at the low pressure outlet of the recer is p < 0.12mpa, the alarm will be given, and the standby pump motor will start at the same time; When the oil pressure P ≥ 0.4MPa, the standby pump stops; When p ＞ 0.5MPa, it will alarm
7) the temperature of one of the five bearings in the recer is t > 60 ℃
8) oil temperature of hydraulic station of recer T > 55 ℃
9) heat exchange of recer

6. In this way,
you spend a long night, from the moonlight on you to the wheel rolling across the horizon<
the love of acacia is more firm:
as long as there is a ray of light on the grassland,
you will be foolishly careful.
like a cat, you will keep cooking smoke

7. (1) Strictly follow the operation principle of timely updating according to the spontaneous combustion cycle of coal. The
stacker and reclaimer of circular coal yard rotate in the same direction with the center column as the center, the reclaimer is in the front, and the stacker is in the back, so as to realize the "first in first out" cycle operation mode of coal storage, and ensure that the coal storage renewal cycle is less than the spontaneous combustion cycle
this is the most effective basic measure to prevent spontaneous combustion of stored coal. Whether it is automatic operation or manual operation, the stacking and fetching positions should be strictly controlled according to the "first in first out" mode. It is strictly forbidden to change the stacking and fetching positions at will, so as to control the renewal of stored coal in the spontaneous combustion cycle of
coal

(2) when the scraper reclaimer is pitching and rotating along the surface of the coal pile, it should take all the coal, and clean the coal in the
part of the retaining wall root, so as to create a good condition to prevent spontaneous combustion. Special attention should be paid to the spontaneous combustion of coal that can not be used temporarily e to special reasons

(3) in the process of coal unloading, the coal unloading personnel should pay attention to observe the situation of coal coming. Once it is found that there are white smoke and other phenomena that are about to spontaneous combustion, the first choice is to directly enter the main power house, and the second is to send the coal to the circular coal yard reclaiming area, and send it to the main power house as soon as possible
(4) the coal handling program control room should be on ty 24 hours a day, and it is one of the main responsibilities to monitor the situation of coal transportation in the coal yard and along the belt conveyor. The operation inspection personnel of each shift should pay attention to observe the situation of coal in the process of transportation and coal storage in the coal yard, and find and deal with spontaneous combustion in time

(5) in case of local spontaneous combustion of stored coal, it is necessary to immediately stop the coal feeding mode that the coal from outside the plant is directly fed to the main power house and the coal is taken from another circular coal yard, and adhere to the "first in first out" operation mode as far as possible, so as to quickly

 The upper coal in the spontaneous combustion area is sent to the main power house. In the process of conveying, the water can be sprayed and cooled by the
spray device set at the outlet of the guide trough along the way. When the deep spontaneous combustion coal is exposed, it is put out by fire water monitor or other disposal to avoid further expansion of spontaneous combustion range
(6) if the local spontaneous combustion of stored coal deteriorates rapidly, and there are extremely urgent and special situations such as open fire, the fire water monitor should be used immediately to put out the fire, and the reclaimer should be transferred to the spontaneous combustion area to take the upper coal, and the fire water monitor should be equipped with
combined reclaimer. After natural treatment, the reclaimer must return to its original position and return to the "first in first out" operation mode.

8.

1、 Cement: all fine grinding materials, add appropriate amount of water, into a plastic slurry, that is, can harden in the air, but also in the water hardening of hydraulic cementing materials, and sand and other materials can be firmly cemented together called cement. Generally speaking, Portland cement is proced in the cement instry. Portland cement is a fine, usually gray powder, which is composed of calcium and calcium&# 8194; From limestone&# 8194; Silicate and aluminate&# 8194; Clay&# 8194; And ferrite

there are vertical kiln (including mechanical kiln), rotary kiln (rotary kiln) and ᦇ 8194; The form of raw meal into the kiln is dry method and wet method. If the raw meal is slurry, it is wet method&# 8194; Generally speaking, the daily output of cement can be divided into three categories according to the use and performance: Cement (8194) cement (8194) cement (8194) cement (8194) cement (8194) cement (8194) cement (8194) cement (8194) cement (8194) cement (8194) cement (8194) cement (8194) cement (8194)

1. General cement; Cement is generally used in civil engineering. General cement mainly refers to six types of cement specified in GB 175-1999, GB 1344-1999 and GB 12958-1999, namely Portland cement, ordinary portland cement, slag Portland cement, pozzolanic Portland cement, fly ash Portland cement and composite Portland cement&# 8194;

Special cement, special purpose cement. Such as: grade G oil well cement, road Portland cement&# 8194;

Characteristic cement, a kind of cement with outstanding performance. Such as: fast hardening portland cement, low heat slag Portland cement, expanded sulphoaluminate cement&# 8194;

(2) according to the name of the main hydraulic substances, cement can be divided into four categories: &

(1) Portland cement is commonly known as Portland cement abroad

(2) aluminate cement

3  Sulphoaluminate cement

(4) ferroaluminate cement

(5) fluoroaluminate cement

(6) cement mainly composed of pozzolanic or potential hydraulic materials and other active materials&# 8194;

(3) the main technical characteristics of cement indicated in the cement nomenclature can be divided into: &

1  Fast hardness: it can be divided into fast hardness and super fast hardness&# 8194;

2  Heat of hydration: it can be divided into medium heat and low heat&# 8194;

3  Sulfate resistance: divided into medium sulfate corrosion resistance and high sulfate corrosion resistance&# 8194;

4  Expansibility: it can be divided into expansion and self stress&# 8194;

5  High temperature resistance: the high temperature resistance of aluminate cement is graded according to the content of alumina in cement&# 8194;

(4) general principles of cement nomenclature&# 8194;

1. According to different categories, the naming of cement should be based on the main hydraulic minerals, mixed materials, uses and main characteristics of cement, and try to be concise and accurate. If the name is too long, it is allowed to have a short name&# 8194;

2. General cement is named after the main hydraulic mineral of cement, followed by the name of mixed material or other appropriate name&# 8194;

3. Special cement is named after its special purpose and can be labeled with different types&# 8194;

The characteristic cement is named after the main hydraulic mineral of cement and the main characteristics of cement, and can be named after different types or mixed materials&# 8194;

Cement with pozzolanic or potential hydraulic materials and other active materials as the main components is named after the name of the main component and the name of the active material, and can also be named after the characteristic name, such as gypsum slag cement, lime pozzolanic cement, etc.

6, They are: raw meal preparation (first grinding), clinker calcination (first sintering), cement grinding (second grinding). In a silicate medium; In cement plant, cement proction has the following main stages

Second, the preparation of raw meal

(1) limestone is the main raw material for cement proction, limestone is the main raw material for cement proction, about 1.3 tons of limestone is needed for each ton of clinker proction, and more than 80% of raw meal is limestone. Most of the plants are located near limestone quarries to minimize transportation costs

1&# 8194; Limestone, shale, (?) 8194; Silica and pyrite&# 8194; The extraction of the&# 8194;&# 8194;·&# 8194; The raw material is sent to the crusher, where it is broken or hammered into pieces

The crushed limestone and other raw materials are usually covered and stored to prevent the influence of the external environment and rece the st to the greatest extent&# 8194;

In most cases, quarries and cement plants will need separate or separate power supply equipment&# 8194; Limestone is the raw material with the largest amount of cement consumption. After mining, the particle size is larger and the hardness is higher. Therefore, the crushing of limestone plays an important role in the material crushing of cement plant

(2) raw material crushing and pre homogenization&# 8194;&# 8194;&# 8194;

(1) broken and broken&# 8194;&# 8194;&# 8194; In the process of cement proction, most raw materials are crushed, such as limestone, clay, iron ore and coal. Limestone is the raw material with the largest amount of cement consumption. After mining, the particle size is larger and the hardness is higher. Therefore, the crushing of limestone plays an important role in the material crushing of cement plant&# 8194;&# 8194;

the raw and fuel materials are transported by mp truck and poured into the mp pit, and then fed into the crusher by plate feeder for crushing. The crushed raw and fuel materials are sent to the pre homogenization yard by belt conveyor&# 8194; &# 8194;&# 8194;&# 8194;

(2) pre homogenization of raw materials&# 8194;&# 8194;&# 8194; Pre homogenization technology is to realize the initial homogenization of raw materials by using scientific stacking and reclaiming technology in the process of storage and reclaiming of raw materials, so that the raw material yard has the function of storage and homogenization at the same time&# 8194;&# 8194;

the crushed raw and fuel materials were pre homogenized and stacked in layers by the stacker, and then picked up by the scraper reclaimer. The raw materials are transported to the raw material batching station by belt conveyor&# 8194;

(3) main equipment&# 8194;&# 8194;&# 8194; &# 8194;&# 8194;&# 8194;&# 8194;

1&# 8194; &# 8194; Layout position; It is located in limestone crushing workshop&# 8194;&# 8194; Use the following formula:; The way is to reach 8194; It is used for limestone feeding&# 8194;&# 8194; &# 8194;&# 8194;

2&# 8194;&# 8194; Use the following formula:; The way is to reach 8194; Used for crushing limestone&# 8194;&# 8194; Layout position; It is located in the limestone crushing workshop of the plant area; Crushing type # 8194; Single stage hammer (pcf20.18) & 8194&# 8194;

3. Limestone mixing stacker reclaimer

3&# 8194;&# 8194;

1. Raw meal preparation&# 8194;

in the process of cement proction, at least 3 tons of materials (including various raw materials, fuels, clinker, mixtures and gypsum) should be ground for each ton of Portland cement proction. According to statistics, the power consumption of grinding operation of dry process cement proction line accounts for more than 60% of the power of the whole plant, of which raw material grinding accounts for more than 30%, coal grinding accounts for about 3% and cement grinding accounts for about 40%. Therefore, reasonable selection of grinding equipment and process flow, optimization of process parameters, correct operation and control of operation system are of great significance to ensure proct quality and rece energy consumption&# 8194;&# 8194;

in this stage, vertical mill and ball mill are used, the former uses the pressure released from the drum; The material passing through is crushed, and the latter relies on steel balls to grind the material&# 8194; &# 8194; &# 8194;

(1) proction process of old-fashioned ball mill: according to the set raw material ratio, four kinds of raw materials in the raw material proportioning warehouse are transported to the grinding head by seven quantitative feeders and belt conveyors, and then enter the feeding bin of roller press through the gate. After the materials are pre crushed by roller press, they are sent to the powder separator by the crusher, and the selected coarse powder enters the mill for grinding, The grinding materials are sent to the separator (cyclone) through the elevator, and the qualified procts selected by the separator (cyclone) are sent to the raw material warehouse&# 8194; &# 8194;

when the roller press fails, the material can be directly sent to the mill for grinding through the gate control. The ground raw material enters the separator from the upper part, and is separated by the separator. The coarse powder is discharged from the lower part, and the qualified fine powder is brought into the cyclone by the rising air flow. The gas material is separated in the cyclone, the st containing waste gas is extracted from the upper part to the st collector, and the finished proct is discharged from the lower part to the raw material bin. Although the system works continuously, the proction efficiency of the system will be affected at this time&# 8194;

the raw mill is filled with waste hot gas from the firing system. In the process of grinding materials, the materials are dried at the same time. The st containing waste gas from the mill and another waste hot gas from the kiln tail will enter the powder concentrator, and the st containing waste gas from the powder concentrator will be sent to the bag st collector and discharged into the atmosphere after purification&# 8194;

(2) working principle of separator:

four cyclones are distributed around the middle body of separator. The ground raw material enters the separator from the upper part, and is separated by the separator. The coarse powder is discharged from the lower part, and the qualified fine powder is brought into the cyclone by the rising air flow. The gas and material are separated in the cyclone, the st-containing waste gas is extracted from the upper part to the st collector, and the finished proct is discharged from the lower part to the raw material bin to prepare for firing&# 8194; &# 8194;

(3) the working principle of the new type of raw meal vertical mill: (with powder concentrator) &

Vertical mill is used for raw meal grinding. This type of mill integrates the advantages of grinding and drying, so it has high drying and grinding capacity. Three gates are used at the entrance of the mill to lock the air and feed

At the same time, 300 ℃ waste gas from the kiln tail high temperature fan enters into the mill from the air inlet of the vertical mill. Under the action of centrifugal force, the material moves to the edge of the grinding plate and is crushed by the grinding roller when passing through the annular groove on the grinding plate, The comminuted material is brought up by the high-speed air flow at the edge of the grinding plate, and the large particles fall directly on the grinding plate for regrinding. When the material in the air flow passes through the separator, under the action of the rotating rotor, the coarse powder falls on the grinding plate for regrinding, and the qualified fine powder comes out with the air flow

The qualified fine powder is carried into the cyclone by the rising air flow. The gas material is separated in the cyclone, the st containing waste gas is extracted from the upper part to the st collector, and the finished proct is discharged from the lower part to the raw material bin to prepare for firing. There is also a part of coarse powder in the raw mill passing through the wind ring. Because it can not be taken away by the air flow, it is scraped out by the scraper to form the external circulation material. The maximum circulating capacity of this part is 40t

Raw material ball mill is mainly used for grinding finished procts and raw materials in cement plant, and also for grinding various ores and other grindable materials in metallurgical, chemical, electric power and other instrial and mining enterprises. It can be used for open flow grinding, and it is also suitable for circular flow grinding composed with powder concentrator&# 8194; &# 8194;&# 8194;&# 8194;&# 8194;

The raw material ball mill has the characteristics of strong adaptability to materials, continuous proction, large crushing ratio and easy to adjust the fineness of grinding procts. It can be proced either by dry method or by wet method, or by grinding and drying at the same time&# 8194; &# 8194;

Compared with ball mill, vertical mill has the following characteristics&# 8194; &# 8194;&# 8194;&# 8194;&# 8194;

The grinding efficiency was high; Large drying capacity; The size of the material to be grinded is large, and the secondary crushing can be avoided in the large and medium-sized vertical mill; The chemical composition of the proct is stable;