1 Introduction1.1 OutlineThe design reference Baosteel sintering plant, according to the design requirements of the mission statement, the design production capacity of 300 tons, the sintering plant products of high quality for blast furnace sinter.Because annular cooler temperature exhaust gas discharged with the airflow and fine dust released into the air, allowing more serious environmental pollution, while a large number of hot exhaust gas into the atmosphere, waste heat, dust and heat in order to reduce emissions, reduce pollution of the environment, the design of the ring after a hot exhaust gas cooler dust stove and holding furnace used for point after.The design of the sintering engineering technology, equipment level and the degree of automation and, basically, Baosteel sintering plant rather, is the world's advanced level, the design of a complete process: thick material layer sintering, centralized dust removal system, dual diagonal band spot stove, the addition of a ring cooler holding furnace and hot exhaust gas emissions as a promoter, these are the sintering process technology and equipment constitute the main content, but also an important indicator of the level of today's world.1.2 Design basis and design principles1.2.1 Design basisThis design is the Central South University of Resources Processing and Bioengineering pellets Professional 2013 session of the graduate design task, entitled "Design sinter plant of an annual output of 3 million tons of sinter" which combined in Baosteel graduation internship process field data collected and the master site processes and equipment prepared on the basis of.1.2.1 Design principlesIn order to do this sinter plant design, intended to the following design principles:1) According to today's world sintering technology, combined with the actual situation of Baosteel, determine the design process technology and equipment level.2) reasonably compact device configuration, production workshop has sufficient operating area to ensure smooth material transport facilities.3) selection of equipment, construction to achieve standardization and universal.4) Take effective measures to reduce the sinter plant dust pollution.5) Consider the possibility of future expansion.1.3 Design rangeThe design of the sintering project include the following:1) coke crushing and screening system.2) ingredients mixed system.3) sintering and cooling system.4) the main electrical room.5) finished crushing and screening system.6) the dust handling system.2 Iron-containing materials, flux, fuel2.1 iron-containing materialsThe design of the sintering plant iron raw materials including imported iron ore , national concentrates.Imported iron ore is a high iron low silicon raw materials, mainly from India, Brazil, Australia and other importing countries. Imported Materials ore from the steamer pier, transported by belt conveyor to the raw material yard, through Neutralization and mix on the yard, then by belt conveyor to the dosing chamber, Sintering plant mainly recyclable materials is iron by the belt conveyor to the field and mixed with other Materials Materials , to pre-dosing effect. Iron-containing materials in the yard after mixing , directly to the dosing chamber.2.1.1 Chemical composition of iron-containing materialsThe chemical composition of iron-containing materials into the plant in Table 2-1.2.1.2 The requirements Size and grade1) the size requirements: Fines <8mm.(2) grade requirements: iron grade fluctuation range ±0.5%;FeO fluctuation range ±0.1%;S fluctuation range ±0.08%.2.2 FluxBecause most iron raw materials used is high-speed rail low silicon raw material,in order to improve the quality of sinter and improve the fluidity of slag, this design uses dolomite, limestone and quicklime as flux. Mixture granulated quicklime The quicklime is used to enhance mixture granulation and improve the permeability3.Sintering Process Selection and VerificationAccording to material properties, select the appropriate sintering method, processing procedures and process systems，in order to obtain the desired product. Sintering process designed mainly for the process of analysis and the basic principles for selection process .3.1The meaning and requirements for selecting processProcess is an integrated of certain processes from production process.Sintering process of selection is an important part of the design process. A new sintering plant around all the design elements are determined by the unfolding process. Reasonable production process, equipment capacity is full, rational organization of production, to ensure continuous production, access to advanced technical and economic indicators of important factors. Therefore, the process of selection, must be fully considered, multi-program comparison.Process selection requirement is to ensure the product quality requirements of the premise, to maximize the use of various iron-containing materials, and access to high labor productivity and equipment utilization, conserve energy as much as possible to save production costs for enterprises to seek maximum profit; and to adopt modern means of production, strong labor intensity, improve operational and management level; should consider radical waste pollution, protect the environment and health, protection of workers' health.3.2 Raw materials, flux and fuel3.2.1Raw material preparationThe raw materials used to design the main ore powder, powder ore controls below 8mm size requirements, into the iron-containing raw materials and sintering mix ingredients in order to achieve results. This procedure offers a raw material in thesteel mill plant, mix mine via conveyor belt to produce sinter plant ingredients.Sintered material into the sinter plant conditions:1) bonanza powder particle size should be 8-0mm (also available 6-0mm), ore particle size of more than 10% +8 mm will affect the quality of sinter. Special powder size requirements should be based on experimentally determined. SiO2 content fluctuations should be less than or equal ± 0.2%. Iron grade fluctuations should satisfy the following conditions; large and extra large sinter plant should be less than or equal ± 0.5%; medium-sized sinter plant should be less than equal to ± 0.75%; small sinter plant should be less than equal to ± 1.0%.2) magnetite concentrate moisture should be less than 10%, hematite concentrate moisture should be less than 11%. Concentrate moisture exceeds this requirement, the proportioning accuracy, affecting mixing uniformity.3) Blast should be appropriate wetting dry dust, blast furnace and BOF dust and sludge secondary dust should be dehydrated, so that water is less than 15%.4) Rolling Paper size not greater than 8mm.5) of the iron-containing material harmful impurities should be limited as required.When raw iron grade volatile than <sintering plant design requirements> requirements, should be shot mix stockyard and, if possible together with the steel plant was built in order to achieve sintering, pelletizing plant feed ingredients stable, uniform size. For medium and small sintering plant should also be set up according to the specific conditions of mixing facilities; raw single species, grade fluctuation is small, or not to set mixing facilities. But it should be built by the mining of raw materials warehouse and warehouse and so on. There blending stockyard, the sintering plant should no longer raw materials warehouse. But in wet areas should be located indoor storage facilities.Medium-sized sinter plant material should be adopted by the dumper. Dumper is a large unloading equipment, which is widely used in large and medium-sized and some large sintering plant sinter plant. It has the unloading of high efficiency, large capacity, suitable for all kinds of bulk material unloading turn. Because high degree of mechanization, is conducive to automated or semi-automated unloading operations.By mine shafts is used only by the material and not for storage facilities. Generally used for steel mills to accept bulk materials and auxiliary materials. By mine chute design should consider the use of mechanized equipment. Small mines can be spiral unloading machine or a chain-head unloading machine to accept raw materials. Most of the raw materials warehouse sintering plant designed to stabilize production, raw materials warehouse storage time of various materials as follows: iron-containing materials, a dedicated transmission line for the five days, no special transport line for the seven days; fuels and solvents , a dedicated conveyor line for the 3-5 days, no special transport line for 7 days. As for the small sinter plant under specific conditions. Freezing cold regions receiving and storage of raw materials should have anti-freeze thawed facilities.3.2.2 Flux preparationSintering production on the granularity of flux, there are strict regulations generally require 3 ~ 0mm content should be greater than 85% while the flux into the plant size is 40 ~ 0mm, so you need to be broken.Flux in the raw material crushing plant is complete. Dolomite, limestone crushing to the required 3 ~ 0mm, via tape machine to the dosing chamber. Lime particle size of 3 ~ 0mm, from the limestone, dolomite roasting plant is provided with a suction pressure tank to the sintering plant dosing chamber, and then compressed into the batching tank.(1) flux crushing and screening process generally has three:1) Open broken rod mill machining processes.2) Closed hammer crusher crushing and screening process flow.3) Impact Crusher closed circuit crushing and screening process flow.Closed flux machining processes are generally used in closed-circuit crushing and screening processing flow, can be divided into two kinds of pre-screening and screening examination. When the flux ore 3-0mm level content more time (generally 30% -40% or more), before use of pre-screening. Otherwise, adopt screening. Check the screening process sieve material for the product, the oversize material back into the crusher heavy breaking. More generally sintering plant using this process.Closed flux machining processes are generally used in closed process, can be divided into pre-screening and pre-screening process closed-circuit crushing and screening checks closed circuit combining two kinds. When the flux ore 3 ~ 0mm level for a long time (generally 30% to 40%), before use of pre-screening. Otherwise, the check screening. Check the screening process under size product for the product, the oversize material back into the crusher broken again. Taking into account the material conditions of this design, the design uses a closed circuit with a screening examination.(2) broken equipmentConsidering the physical properties of raw materials, production capacity and size requirements, the advantages and disadvantages of the crushing equipment discussed below:1) Impact CrusherScope: brittle, medium hard minerals (metallic, C), sintering plant (limestone, dolomite).Advantages: uniform size, over crushed small, light weight, low power consumption, large capacity, large crushing ratio.Disadvantages: vibration, noise, dust, wear big.2) hammer crusher (reversible and irreversible)Scope: brittle, medium-hard, hard and soft minerals (limestone, dolomite and serpentine), the crushing (3 ~ 0mm), rarely used in primary crushing.Pros: large capacity, large crushing ratio; structure is simple, compact, low power consumption and easy maintenance.Disadvantages: wear and high moisture blocking material is easy.3) rod millScope: Baosteel crushing equipment used in the second paragraph of coke.Advantages: too little crush.Disadvantages: high power consumption, low output and heavy equipment.4) four roller crusher (on the roll)Scope of application: Widely used in sinter plant fuel broken.Advantages: can be completed in time, fine, no screening classification, simpleprocess.Cons: roller uneven wear.Common flux crushing equipment crusher and hammer crusher two kinds.Crusher has uniform particle size, over crushed small, light weight, low power consumption, large capacity, large crushing ratio, etc., hammer crusher with high yield, large crushing ratio, low power consumption per unit of product, easy maintenance, etc. advantages in the production of the two devices is different, but the impact crusher vibration, noise, dust capacity, wear and therefore in the design selection hammer crusher. Hammer crusher can be divided into two kinds of reversible and irreversible and reversible hammer crusher hammer function to extend the service life and ensure the crushing efficiency, so the design are made of reversible hammer crusher.(3) screening equipmentSintering plant flux screening equipment is mainly shaker.The design uses a self-centering shakerSelf-centering shaker has the advantage of simple structure, use, operation and replacement of the screen surface is more convenient, strong vibration sieve surface, and the vibration direction perpendicular to the screen surface can reduce the material clogging the sieve of the phenomenon, with high screening efficiency (up to 90 ~ 95%) and production capacity, suitable for medium, fine screening, does not apply to coarse sieve.The disadvantage is that the amplitude of the sieve with the size of the amount to the mine fluctuate, resulting in screening efficiency is not stable enough; sieve in the process of starting and stopping, through resonance, the amplitude increases, a greater impact on the sieve and buildings.11。