3.4　Quantity of Pulverized Coal Injection

3.4.1　PCI quantity shall be determined according to conditions such as raw materials，fuels，air temperature，oxygen enrichment，BF top pressure，and blast humidity.PCI quantity under different smelting conditions should be in accordance with those specified in Table 3.4.1，and shall comply with the following requirements:

1　If blast is of natural humidity and the hot air temperature is between 1050°C-1100°C，the lower limit in Table 3.4.1 shall be used.

2　The upper limit in Table 3.4.1 may be used under the following conditions:high coke strength，small slag quantity，dehumidified blast，hot air temperature of 1200°C-1250°C，and BF top pressure over 0.20MPa.

Table 3.4.1　PCI quantity under different smelting conditions

3.4.2　If the smelting conditions exceed the specified range in Article 3.4.1 of this Standard，PCI quantity can be determined through calculating the theoretical combustion temperature before tuyere.The theoretical combustion temperature before tuyere should be 2100°C±50°C.

3.4.3　Equipment capacity of PCI system shall be surplus to the PCI quantity for BF，but the maximum PCI quantity should not be larger than 250kg/tHM.