Nickle pig iron is the results of limonitic type laterite ore blended with flux and coke in the blastfurnace or others processing that has passed several phases among of them are drying and sintering of ore .The Mixtures have to fullfil the requirement to reach standard of nickle content in NPI.The government regulation have standard about 6 % nickle content in NPI to share in the market.
There are some levels of nickle content which circulated in particulary china's market based on the nickle content ; low grade,middle grade and high grade which the content of each levels are 1.6-1.7 %,6-8 %, and 10-15 % NI ,respectively.
To produce the High grade NPI we need ore which are high amount of nickle in ore and low content of iron in ore.There are several type of ore which consists nickle and iron in the ore ; limonite and saphrolite ore are generally found in Indonesia mining of nickle.The content of nickle in the limonite type between 1.6 - 1.7 % and Saprolite have content of nickle about up to 2 %.In several case we must be blending between limonite and saprolite ore to reach the requirement nickle content in ore to result The NPI desired.
After the mixture has been reached in the standard requirement of nickle content to achive the desired NPI product.Then the Mixture will be futher processing in the sintering machine.Sintering machine is the processor machine the blended ore becoming larger particle size of ore. The ore has been agglomerated with high porosity to be sent with conveyor in the blastfurnace machine to melt the materials in the high temperature up to 2000 celcius degree together with coke and Flux as mixtures to get slag and molten iron or Nickle.Fuel for sintering machine obtained from blast furnace gas that will combust with air untill to have 1500 celcius degree.