4.3　Process Equipment

4.3.1　The hot metal pretreatment station shall include ladle transfer and tilting device（no tilting device is needed if a slag dredging process is adopted），slag removing device，slag pot（pan）and transfer device，powder injection lance and lifting mechanism（or stirring head and rotating and lifting mechanism），powder storage and distribution（or feeding）system，and temperature measuring and sampling device.

4.3.2　Ladle car shall be provided with emergency traction device.

4.3.3　The hot metal pretreatment station should be equipped with an automatic temperature measuring and sampling device and the probe inserting depth shall be 300mm-500mm below hot metal level.

4.3.4　For the gas piping of hot metal pretreatment unit，the control valve shall be electric or pneumatic and also provided with indication of valve position.

4.3.5　The power bin shall be provided with the capacity for≥24-hour operation.If the material is transported pneumatically，the design of bin shall be based on the operating pressure of at least 2kPa and a pressure relief device shall be provided.

4.3.6　The storage bins for lime powder，calcium carbide powder，carbon powder and magnesium powder shall be provided with dry nitrogen protection.

4.3.7　The pretreatment unit with injection process shall be in accordance with the following provisions:

1　Each co-blown desulfurization station shall be provided with 2 injection buckets and a（or 2）powder injection lance with refractory.Respective injection bucket shall be provided for different powders.

2　A desulfurization station with only powder injection shall be provided with an injection bucket and a powder injection lance with refractory.

3　For the injection bucket，the capacity shall meet the demand for≥1 heat and the maximum operating pressure should be designed as 1.0MPa.The fluidizing part at outlet of injection bucket should adopt a removable structure.

4　For the hot metal pretreatment unit with injection process，the error of powder weighing system shall be less than±0.5%.The weight of material shall be indicated in decrement mode and the indication shall include injection rate.The weighing signal shall be interlocked with automatic control of injection operation.

5　For powder injection，standby lance shall be provided.

4.3.8　The pretreatment unit with mechanical stirring process shall be in accordance with the following provisions:

1　The stirring head shall be lifted with double-wire-rope hoist and also the wire rope adjusting and balancing mechanism and the detector for wire rope overload and fall-off protection shall be provided.The stirring head shall be provided with an emergency lifting device.

2　Stirring head replacement pallet shall be provided.The VVVF control shall be adopted for rotation of stirring head.The rotation speed shall be 15r/min-150r/min.

3　The rotating spindle and stirring head should be provided with internal gas cooling and spraycoated with refractory castable on the surface.

4　The desulfurizing agent feeding chute should be telescopic.