Strengthen the stability of sintering operations

Release date 2024-12-17 14:44:09 Reading 2

　　used excavator for saleThe world's highest altitude wind farm in China generates over 22 million kilowatt hours of electricity

　　The highest cabin altitude is 5305 meters! The record for the highest number of wind power projects completed and put into operation in China and globally has once again been broken.

　　In the remote plateau mountainous areas of eastern Tibet, 20 silver white windmills rotate in the wind, and a set of 95 meter long blades can generate 9.5 degrees of electricity for every rotation!used excavator for sale

　　This wind farm is located at an average altitude of 5050 meters in Basu County, Xizang, and is invested and constructed by Datang Xizang Energy Development Co., Ltd. and Changdu Kangdian Clean Energy Investment Development Group Co., Ltd. Since its commissioning on October 31st, as of 8:00 am on December 10th, it has generated a total of over 22.42 million kilowatt hours of electricity.used excavator for sale

　　In the past, the county town often experienced power outages, but in recent years, the power supply has become increasingly stable. "Luo Songzeren, a wind farm operation and maintenance technician, is from Basu County. The scene in his memory where every household had to prepare oil lamps no longer exists.

　　This wind farm with an annual power generation of 223 million kilowatt hours can meet the annual electricity needs of about 230000 people. The project leader Xu Qiduo introduced that the generated electricity is integrated into the Changdu area power grid, and most of it is locally consumed to meet the local electricity demand.

　　"These 20 windmills can save about 73100 tons of standard coal and reduce about 182800 tons of carbon dioxide annually," said Shi Lei, a professor at the School of Ecological Environment of Renmin University of China.

　　The area with an altitude of 3500 to 5500 meters is called a super high altitude region, which is a "rich mine" of wind energy resources.

　　It is estimated that the area where the wind energy resources in Xizang are more than 7m/s accounts for about 30% of the total area of the region, which is mainly distributed in high mountain areas with an altitude of more than 4800m, and the technically exploitable amount is about 180 million kilowatts. The Bangda grassland surrounding the Basu wind farm has been measured to have an instantaneous wind speed of 38 meters per second, equivalent to a 13 level gale.

　　Clean energy power generation in Xizang accounts for more than 99%, ranking first in China; However, hydropower and photovoltaics account for about 50% and 40% respectively, while wind power currently accounts for less than 10%.used excavator for sale

　　However, here the demand for wind power places higher demands on technology and equipment: low air density can cause unit stall, low air pressure can reduce electrical insulation performance, high ultraviolet radiation can accelerate component aging, high turbulence, large changes in wind speed and direction are difficult to evaluateused excavator for sale used excavator for sale used excavator for sale

　　What is the key to steadily advancing wind power into high-altitude areas? The answer is technological innovation.used excavator for sale

　　The single unit capacity of these "high-altitude windmills" at the Basu Wind Farm is 5 megawatts, which is the largest value used in the industry in ultra high altitude areas. These 20 doubly fed wind turbines are precisely customized for high-altitude and cold regions, designed and developed by CRRC Zhuzhou Electric Locomotive Co., Ltd. They can ensure electrical safety in extreme environments such as strong ultraviolet radiation, high thunderstorm frequency, and frequent snowfall.

　　And daily operation and maintenance of these huge windmills only require 8 to 10 people.

　　In the central control room, which is one hour's drive away from the wind farm, the operation and maintenance of the farm are highly intelligent. Through the screen, Luosong Zeren can monitor the instantaneous wind speed, instantaneous power generation, and cumulative power generation of all wind turbines in real time; Click on the details of a single fan, and the parameters such as impeller speed, generator speed, wind direction, and cabin angle are clear at a glance.

　　"The multi energy complementary pattern formed by the development of wind power can make up for the gap formed by the shortage of hydropower in Xizang in the dry season and the lack of photovoltaic at night," said Shi Leiused excavator for sale

　　Diligent cultivation, ingenious inheritance, innovative development, and forging aheadused excavator for sale

　　Innovation is an eternal theme of social development, and the development of enterprises and society requires innovative talents to continuously guide, inspire, and tap into the innovative potential of all employees, contributing to the development of enterprises. With the rapid development of technology and increasingly fierce market competition, innovation has become the key to the sustainable development and competitiveness of enterprises. In this context, in May 2023, Jin Gang Holdings Group's sintering plant, led by the production technology department of the sintering plant, Xiao Qian, and with strong support from leaders at all levels, organized the second level supervisors and engineers as the backbone to jointly establish the sintering plant innovation studio, aiming to provide a comprehensive platform focused on innovative thinking and technology research and development.

　　The source of innovation, forging brillianceused excavator for sale

　　After a year of exploration and research, team members gradually formed a comprehensive closed-loop management system based on their division of responsibilities, including overall planning, application of achievements, safety and environmental protection, production processes, mechanical equipment, electrical automation, material support, and implementation supervision. They focused on implementing the annual production and operation goals of the group company, actively carried out technical research, invention and creation, management innovation, and other key and difficult issues related to enterprise safety production, cost reduction and efficiency improvement, intelligent enhancement, independent innovation, and company image enhancement, and achieved multiple research results.

　　Technological innovation leads the industryused excavator for sale

　　1. Independently develop a white ash digestion device

　　The main component of quicklime is CaO, which reacts with water to form Ca (OH) 2, expands and releases heat, which is very beneficial for improving the granulation of the mixture. The native lime system lacks pre digestion equipment for adding water. In production, quicklime is not fully digested with water to form a slurry. It is transported to a primary mixer where it is mixed with other raw materials (including mixtures, fuel, and return ore) by adding water. Due to the strong hydrophilicity of quicklime, the hydrophilicity of the mixture and return ore is poor, and there are significant differences in particle size. Mixing various raw materials with water not only slows down digestion, but also cannot fully digest them, resulting in uneven dryness and wetness, poor material mixing effect, greatly affecting the balling effect and the permeability of the sintered material layer. There are many white spots and low agglomeration rate in the sintered ore, leading to a decrease in the quality of the sintered mineral.used excavator for sale

　　In order to avoid the loss of quicklime and provide sufficient digestion time (2.2-3.5 minutes), technical improvements have been made to the batching system. Make and install two separators. First, cut a groove for the sintered material on the belt, and then add quicklime into the groove to form a protective wall for the sintered material. After the addition of quicklime, it is immediately sprayed with water. Finally, cover the trench with other sintered materials.used excavator for sale

　　The digested lime is in a paste like form, which is mixed with fuel and iron materials to avoid uneven dryness and wetness caused by significant differences in hydrophilicity, enhance the mixing effect, and strengthen granulation and pelletizing. The quicklime has been fully digested, reducing the occurrence of white spots in sintered ore and improving the yield of sintered ore. The return rate decreased by 0.11% in June and 0.66% in July compared to before the transformation. Through the above technological improvements, the digestion time of quicklime has been increased and its effective utilization rate has been improved, resulting in an increase of about 5% in sintered ore production.used excavator for sale

　　2. Fuel crushing U-shaped belt technology changed to flat belt

　　The particle size and composition of solid fuel in sintered mixtures directly affect the production, quality, and solid fuel consumption of sintered ore. When the fuel particle size is too fine (less than 0.5mm), the heat generated during the sintering process is relatively dispersed, which is not conducive to improving the utilization rate of the fuel and the resulting sintered ore has poor strength, which is not conducive to blast furnace smelting. When the fuel particles are too coarse (greater than 3mm), they are unevenly distributed in the mixture, which easily leads to segregation and concentration in the lower part of the material layer. However, insufficient fuel in the upper part of the material layer results in a loose structure, poor strength, and excess fuel in the lower part of the sintered ore. During the sintering process, the combustion zone becomes wider and the permeability of the material layer decreases, resulting in over melting of the sintered ore, an increase in Fe0 content, a decrease in reducibility, and an increase in coke ratio for blast furnace smelting. At the same time, some of the coarse particles were not fully burned on the sintering machine, and after reaching the ring cooler, they formed secondary combustion and formed large blocks that stuck to the sieve bars of the ring cooler trolley, causing the ring cooler to malfunction and even resulting in a vicious accident of burning the finished product conveyor belt and being forced to stop production.used excavator for sale

　　In the early stage of production, the fuel crushing system's feeding belt inlet plate was horizontal, and the feeding method was drop type. The belt was a regular concave belt supported by three rollers, so the fuel was mainly concentrated within 500mm of the middle of the belt, piled up in a hill shape with a narrow upper part and a wide lower part. After entering the crusher, the fuel was mainly concentrated in the middle of the crushing roller, causing severe wear on the roller skin in the middle of the crushing roller. Due to uneven wear, the contact surface of the crushing roller was uneven during rotation, resulting in periodic hard impacts of the crushing roller during the crushing process. The impact force was huge, causing the main screw to break three times within two months and seriously damaging the equipment. And after the depression, it is necessary to remove the roller skin, usually every 15 days, which shortens the service life of the crushing roller. And the fuel crushing effect is poor,< The proportion of 3mm particles is only 73%.used excavator for sale used excavator for sale

　　In order to improve the qualified rate of fuel crushing quality, enhance the production and quality of sintered ore, and reduce the solid fuel consumption of sintered ore. The members of the studio decided to carry out a technical renovation of the fuel crushing system, widening the receiving port to about the same width as the belt, and changing the discharge port insert plate to a vertical type, so that the fuel can be fully loaded onto the belt. The fuel discharge method became a flat pulling type, and as the belt runs, the fuel is pulled out. By adjusting the opening of the insert plate, the thickness of the fabric on the belt can be adjusted. The belt is then supported by a horizontal roller.used excavator for sale used excavator for sale

　　In this way, the fuel can be evenly distributed on the belt, with the fabric range increasing from 500mm to 940mm, and the thickness being uniform and controllable. After entering the crusher, it is also evenly distributed on the crushing roller, achieving uniform feeding of the crushing roller in the entire axial direction, and realizing synchronous wear of the crushing roller, eliminating the reactive power operation area. At the same time, because synchronous wear is achieved, the contact surfaces of the two contact rollers are always in balanced contact without periodic impact. The sales cycle of roller leather cars has been extended to 2 months.

　　After the transformation, the fuel is evenly spread on the belt and enters the crushing roller and four rollers evenly, improving the crushing efficiency The proportion of 3mm particles has been increased. The proportion of fuel particle size<3mm has increased from 73.807% before the renovation to 76.128%, an increase of 2.32%.

　　3. Automatic water dispensing system

　　In terms of process adjustment, moisture mainly plays a role in granulation, heat conduction, lubrication, and combustion assistance in the sintering process. The stability of moisture control has a direct impact on the yield and quality indicators of sintered ore. Large moisture control, uneven breathability, localized growth, reduced yield and strength. Low moisture control, poor granulation effect, decreased vertical velocity, and decreased yield.

　　Therefore, the higher the stability of moisture control, the more conducive it is to strengthening the sintering process and improving product quality indicators. At present, the moisture control process involves receiving notifications of changes in feeding quantity and structure, recording the time and checking the moisture content, adjusting the opening of the water inlet valve, and checking if the moisture content is suitable. If it is suitable, continue to observe the changes in moisture content. If it is not suitable, adjust the opening of the water inlet valve again.

　　Based on this situation, members of the Innovation Studio collectively discussed and researched, and through continuous experimentation and exploration, achieved an automatic control system for sintering raw material moisture as shown in the following figure.

　　After the transformation, the stability of moisture control has been significantly improved compared to manual control, and the moisture control accuracy can be controlled within the median ± 0.2%, effectively improving the stability of moisture control. Except for the ash discharge period of the ingredient dust collector, automatic water addition is used for all, with a daily operating time of about 23.5 hours, effectively reducing the labor intensity of the post and allowing employees to devote more energy to equipment inspection and cleaning work. The automatic water addition renovation of the 3 # sintering machine mixer is based on fully utilizing the existing equipment, combined with on-site observation of the actual operation of the water worker, and simulated manual judgment through the control program. The actual operation effect is good, which basically changes the current situation of the sintering system that cannot achieve automatic water addition due to process condition limitations for many years.used excavator for sale used excavator for sale used excavator for sale used excavator for sale used excavator for sale

　　Green and environmentally friendly, building the future togetherused excavator for sale used excavator for sale

　　The carbon monoxide produced in the sintering process accounts for 70% of the total carbon monoxide produced in the steel smelting production process. How to make the sintering process more green and low-carbon in 2023 has become a new goal and challenge for all members of the Innovation Studio. The members of the Innovation Studio bent down to the front line, checked the configuration, determined the process, and guided on-site operations. They organized and implemented several measures such as rich hydrogen injection technology transformation, technical transformation of converter gas, and material surface steam injection, achieving the technical goals of "reducing sintering solid fuel consumption" and "reducing carbon monoxide emissions". They explored a new green sintering technology for Jinsteel, which includes "replacing carbon with hydrogen, energy conservation and carbon reduction, and process decarbonization".

　　The Innovation Studio of the Sintering Plant will take reducing CO emissions as a special project for this year, and organize relevant departments such as the Environmental Protection Department and the Raw Material Planning and Development Department to work together. They will hold a research and development meeting every Thursday at the sintering plant, and based on the balance of investment and effectiveness, formulate a research and development plan for the measures that can be taken at present, clarify division of labor and track inspections, and implement it according to the PDCA principle to truly make the plan come to fruition.

　　P-Plan

　　Plan and tackle key issues from four directions: raw material management, process management, equipment management, and process technology improvement. Develop research measures and plans based on their influencing factors, establish goals, decompose responsibilities, and truly achieve the "seven musts" to ensure the perfect implementation of the plan.

　　D - Implementation

　　Management of raw materials and auxiliary materials:used excavator for sale used excavator for sale

　　Reasonably adjust the ore blending structure and solvent structure in combination with H4: prioritize the use of high-quality fuels with uniform particle size, high calorific value, and reduce CO by reducing fuel consumption, while promoting the use of Shanxi coal.

　　Secondary resource recycling material planning: Coordinate with H4 to unify the planning of the company's secondary recycling materials for sintering use, while requiring standardization of W1 mixing materials to reduce material composition fluctuations;

　　Stable dust removal ratio: Establish standards for the use of dust removal ash, stabilize the dust removal ash storage area, and during the CO control period, stop adding dust removal ash.

　　Process management:used excavator for sale used excavator for sale

　　Strengthen the stability of sintering operations: Develop daily parameter control and operation policy standard cards, with the director controlling and strictly following the operation policy to improve process stability.

　　Implement thick material layer operation: FeO intermediate and lower line control, material layer control of 850mm, material layer cannot be adjusted without permission; Reduce FeO centerline control while ensuring smooth operation of the blast furnace.

　　Equipment management:

　　Normalization of air leakage control: Establish an air leakage control research group, led by Liu Hanwei; Provide a detailed list of projects involving air leakage, task assignments, feedback on progress and processing dates, assign responsibilities to individuals, and divide the package into sections.

　　Control the impact of unplanned downtime: Conduct maintenance work on processes, equipment, and facilities to reduce unplanned downtime; List of projects involving production processes and equipment that may shut down, decompose and implement responsibilities, and do a good job in accident prevention and control.

　　Technological transformation:

　　Low negative pressure ignition modification: The sealing of the first, second, and third air box partitions under the igniter was replaced to provide basic isolation and control of negative pressure conditions. A gas material separation device was used. On October 20th, during the maintenance of Unit 2, the modification was carried out, and the negative pressure of 1 # and 2 # air boxes reached below 50%/60% of the main pipe negative pressure.used excavator for sale used excavator for sale used

　　Converter gas transformation: using converter gas ignition instead of existing blast furnace gas ignition; Converter gas has a high calorific value, which can effectively reduce gas consumption, improve ignition quality, and reduce ore return.

　　Steam spraying on the material surface: Steam spraying is added to the flue gas circulation hood of Units 1-4, and three main pipes are modified to achieve segmented spraying.

　　Raise the temperature of the mixture: Calculate the diameter of the main pipe for waste heat steam, re lay the DN80 steam pipeline, use waste heat steam, and raise the temperature of the mixture to above 70 ℃.

　　C-check

　　The Innovation Studio is responsible for supervising, inspecting, and assessing the execution of the production process technology, implementing project progress, assisting project progress, increasing supervision and promotion efforts, and doing a good job in process controlused excavator for sale used excavator for sale

　　A - Processing and Summaryused excavator for sale used excavator for sale

　　A CO emission reduction meeting is held every Thursday in the conference room on the 4th floor of the sintering plant to report on the implementation and completion status, summarize the existing problems, clarify the problems, formulate corresponding measures, and form supervision items for continuous improvement and enhancement.used excavator for sale used excavator for sale

　　Completion achievements:

　　used excavator for saleTalent cultivation, potential stimulation

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