5.2　Proportioning

5.2.1　The series of proportioning line shall be in accordince with the numbers of sinter machine，that is，one proportionign line for one sinter machine.

5.2.2　Automatic proportioning by weight shall be adopted for raw materials，fluxes and solid fuels.

5.2.3　The storage capacity of proportioning bins shall be designed for more than 8 hours operation.

5.2.4　The number of proportioning bins shall be determined according to proportioning ratio and proportioning equipment capacity.The number of major iron-bearing material bins shall not be less than 3，the number of the auxiliary raw material（such as fuels and flux）should be two for each kind of material，and one bin with two feed openings can be adopted for bins with low proportioning ratio.

5.2.5　The major iron-bearing materials and materials with little viscosity shall be proportioned at first.The solid fuels shouldn't be proportioned at first.

5.2.6　The sinter returns and BF returns should be proportioned respectively.

5.2.7　The quicklime or hydrated lime should be used as flux and added in mixture.The addition of the flux shall be determined according to the raw materials conditions and test results.

5.2.8　The setup of quicklime slaking（hydration）facilities shall be determined according to raw material conditions，test results，environmental protection requirements，quicklime dosage and mixing and granulating time.

5.2.9　When the dust reclaimed is proportioned in proportioning system，it should be pre-wetted before proportioning.