Study On Water Reducing Agent For Iron Ore Agglomeration

At present, China’s steel industry is experiencing its winter, how to reduce the energy consumption and production cost, and to improve the comprehensive economic benefit is a problem of pelletizing industry have to face.For iron ore powder,the suitable water reducing agent not only can reduce the water content of the raw ball, and increase the strength of the ball, but also can reduce the ratio of sintering fuel and reduce the emission of carbon dioxide and sulfur dioxide. Therefore, the thesis aims to provide research basis for the selection and use of the water reducing agent of iron ore powder, which is an experimental and theoretical study.In this paper, magnetite, hematite and five kinds of water reducing agent as the research object, through laboratory pelletizing experiment, studied the effect of water reducing agent on the performance of the pellet; By UV, IR, contact Angle measurement method, studied the adsorption behavior of water reducing agent on the surface of magnetite and hematite, preliminary reveals the mechanism of water reducing agent in the pellet. The main research contents and results are as follows:Three suitable water-reducing agents, which are CL, AF, and PCA, were selected.Their better adaptability was determined according to the water-reducing rate of them.By studying the influence of five kinds of water reducer on performance of pellet, and combined with the economic and environmental benefits of water reducer, determine CL is the best water reducing agent which optimal concentration for 7 g/L.Through the infrared identified that adsorption of CL on the surface of iron concentrate as physical adsorption; The adsorption isotherm and kinetics of CL on the surface of magnetite were investigated using residual mass fraction method, the results showed that the adsorption process reaches equilibrium in 20 min, the adsorption kinetics conform to the second-order kinetics model and the adsorption isotherm accords to the Langmuir model. The effect of CL on contact angle of Particle interface was also studied by measuring the permeating height, the results showed that the adsorption decreased the contact angle of the surface of the particles and improved the hydrophilicity of the particles surface.By analyzing the adsorption behavior of CL on the surface of the particles,reveals the mechanism of it in the pellet, the results showed that the adsorption model of CL on the surface of iron ore was an irregular linear adsorption; The adsorption changes the physical and chemical properties of the particle surface, reduces the contact angle on the surface of the particles, increases the hydrophilicity of the surface of Iron concentrate, and increases the capillary force between the particles. On the other hand, CL increased the viscous force of the solution, and the mesh structure ofthe molecules closely connected the iron ore particles, reducing the water content in the pellets, and increasing the strength of the pellets.The main innovation points: more systematically study the lignin sulfonic acid calcium in hematite and magnetite surface adsorption, and adsorption kinetics, and thus reveal the lignin sulfonic acid calcium role in global water reducing, increase the intensity of the internal mechanism.