The control of water and carbon content in mixture  

    The water and carbon content in mixture has an important influence on the sintering process. 

    Sintering process is a complex process of many physiochemical reactions. There are many factors influence on the water and carbon change in mixture so must analyze and judge according to the reflected phenomenon from the production process. The moisture of mixture is connected with particle size composition, chemical composition, hydrophilic and seasonal weather conditions, also with the ratio of raw material, especially the ratio of quicklime and hydrated lime, mixture temperature and storage time of mixture and other factors have close relationship. Under the condition of same water content in mixture, micro phenomenon is large size surface’s moisture looks higher, small size surface’s moisture looks small. Strong hydrophilic material’s moisture looks small, but in fact higher, weak hydrophilic material’s moisture looks high, but in fact not high.  

    Mixture moisture changes not only can take mixture from handpiece to observe directly, but also can be reflected by tail instrument. Generally when moisture is too high, round roller feeder will not work smoothly, feed layer automatic becomes thinner, feeder behind will covers scaly marks, igniter flame spray outward, ignition charge surface have black spots, negative pressure slightly elevate, the tail sintering ore cross-section’s red layer becomes dark, intensity becomes worse. When the moisture is too small, igniter flame spray outward, material surface has float ash, the main negative pressure increases, tail will appears phenomenon of can’t burn through, sintering ore hole is small and loose.     

    The consumption of fuel can be judged directly from tail feed layer section. When fuel is appropriate, sections is normal and not spread, don’t slip lining trolley, red and black layer with no fire. When fuel is much, red layer is thick and bright with fire, sintering ore has large thin wall holes, and the return ore reduces, glue lining trolley serious. When fuel is little, red layer is thin and section’s red layer dulling, section is loose with small hole, large amount of dust, return ore increases. When fuel particle size is big, partial melting is white, take flame, local is black and loose, and glue lining trolley serious. From the igniter: large fuel can make material red face last for a long time; when ignition temperature is normal, material surface is shine and over-melting; less fuel, when trolley out of igniter, material surface is dulling and becomes dark soon. When ignition temperature is suitable, there is partial melt on surface, but the top is not block, easy to be broken. From the instrument: when there is large fuel, the main pipe negative pressure rise, main pipe exhaust gas temperature rise, the tail bellows temperature will also rise; when the fuel is little, temperature will decline, main negative pressure changes little or slightly higher.  

    Generally speaking, experience shows that, when water and carbon is suitable, production is stable, its performance is:

    1. The ignition flame is uniform successfully pumped into the material layer, the trolley leaves igniter, the feed is red to 4 ~ 5 bellows. The tail section is neat, pores are uniform, and no half-cooked material, crimson part is 1/2 of section. 

    2. When the trolley turns in the tail, sintering ore can be removed smoothly, no sticky material. 

    3. The sintering ore block falling from tail is uniform, less powder. 

    4. Under the condition of no change in feed layer thickness, vertical sintering speed, flue gas temperature of big flue and bellows, the degree of vacuum just can change within a narrow range, with sintering end point stable.    

    When the adding amount of water and carbon is not suitable, sintering machine workers should contact mixing machine worker or blend room to change water or fuel; It should also be taken into account to adjust the water or fuel lag process, accordingly increase or decrease material layer, up or down the ignition temperature, add or subtract machine speed for adjustment.