Basic Research Of Straw Fiber For Rotary Hearth Furnace Direct Reduction Process

With the conventional process technology hampered by more and more problems,as a new technology,the rotary hearth furnace coal-based direct reduction technology is booming.Mastering the research status of reducing agent is used in the direct reduction process of the rotary hearth furnace.Our country is faced with the increasingly serious shortage of resources and environmental pollution.As the reducing agent,biomass straw fiber is paid more and more attention.Straw fiber is a waste obtained by jet milling and purification of organic sugar after extracting useful substances through steam explosion-washing-mechanical carding of corn straw,wheat and paddy,etc.At the same time,it is also a clean,renewable reducing agent.Physical and chemical characteristics of straw fiber were investigated firstly.Then the straw fiber used in rotary hearth furnace process for DRI production was discussed.Straw fiber as a reducing agent was used in this process.Box-type atmosphere resistance furnace is used to analog rotary hearth furnace direct production.Analysis and demonstration of straw fiber can replace traditional reducing agent.On the conditions of the carbon containing pellets at different temperatures,particle size,reaction time and a different constant C/O,different reduction effects are as follows.The results show that the fixed carbon content of straw fiber is low,but its hydrogen content is high,ash and sulfur content is low.And its fibrous structure is conducive to improving the balling performance of carbon-containing pellets.Compared with common reducing agent,straw fiber has better reduction effect and higher compressive strength.In addition,the straw fiber carbon-containing pellets also have the advantages of low C/O and short reduction time,the appropriate C/O and holding time is 0.8 and 15 min,and the particle size of straw fiber below 0.15 mm has better reduction effect.