In order to meet the demand of alkaline pellet production line and flue gas desulfurization for lime,it is necessary to build a line kiln with output of 630 000 tons  per year.Based on the basic design conditions,three central burner kilns with output of 600 tons per day using blast furnace gas were built.After ten months of construction,three kilns were delivered for use.According to production situation,the output,quality,consumption,pollutant discharge and other indicators can meet the design requirements and the demands of lime for the production line.