4.4　Fuels

4.4.1　The low heat value of natural gas，coke oven gas or other fuel gases to be fired in straight-grate or grate-kiln systems shall be not less than 16MJ/m3 and the gas pressure shall be not less than 5KPa.

4.4.2　The quality of fuel solid for firing in rotary kiln should be in accordance with the requirements given in Table 4.4.2.

Table 4.4.2　Quality of solid fuel for firing in kiln

4.4.3　Storage，transportation and processing of the fuels shall be in accordance with the following requirements:

1　Gas network，gas station and gas firing systems shall be provided in pellet plant when using fuel gases.

2　In the event of firing fuel oils，oil storage and firing systems shall be provided.The oil supply system shall be provided to satisfy the requirements of oil viscosity and purity which are required for complete combustion.Oil flow rate and pressure shall be stable.Oil burners shall be provided with clean devices.

3　If firing fuel coal，systems for coal storage，crushing and grinding shall be provided.The storage capacity of one month and 7-10 days should be foreseen for long and short distance transportation of coal from origins to pellet plant，respectively.Grinding mill should be vertical type.

4.4.4　Fuel gases to be fired in shaft furnace systems should be blended gases having higher heat values and/or pre-heated blast furnace gases.