(60c) Conversion of Coal Tar into Needle Coke for Utilization in Graphite Electrode & Li-Ion Battery

BACKGROUND:

This innovation is on conversion of coal tar into needle coke which is the main raw material for graphite electrode & Li-ion battery. Presently, 1.8 lakh tons of needle coke is imported in India worth Rs. 3000-3500 Cr. annually. Our company produces 2 lakh tons of coal tar which will be increased to 3 lakh ton by 2030. Coal tar can be converted into many high-end carbon products such as QI free pitch, binder pitch, carbon foam, carbon fiber, meso carbon micro beads (MCMB), anode materials for Li-ion batteries, and needle coke. Needle coke was selected because it has got three major applications: graphite electrode, synthetic graphite (anode materials for LIB), carbon raiser in LD. After successful lab work, we have put up a pilot plant of 1 TPA capacity. Initial testing of the samples shows that properties (carbon content, density, sulphur, volatile matter, ash content) of our needle coke are close to the imported needle coke properties. This project has a potential of ₹ 3000 Cr. new business for our company.

UNIQUENESS:

Coal tar is converted into pitch through distillation and then to needle coke through carbonization process. Needle coke technology is closely guarded, and the process has many know-how/trade secrets to get the desired quality of coke, its needle like structure and other properties. The yield and structure of the final product is very important in deciding the quality of the final product and economics. Typical coal tar distillation gives 50% oil and 50% pitch. Around 25% of anthracene oil (AO) can be distilled off from the distillate oil. This AO, if used directly along with pitch then it will vaporize at high temperature during coking operation. To solve this issue, we polymerized the AO and pitch mixture in presence of catalyst before feeding it to coker unit. The catalyst accelerated dehydrogenation during the polymerization of coal tar pitch and AO. This polymerized pitch is carbonized to get the needle coke. This process increases overall yield up to 5% (from 20 to 25%). Second innovation is on coker design. We designed the coker unit in such a way that it solved many designs related issues.

BUSINESS CONNECT:

Entire amount of needle coke is imported in India. Because of supply chain issue, HEG and Graphite India keep huge amount of inventory. Coal tar produced in BPP can be converted to value added products through this technology. Ultimately this technology will benefit the India in reducing the COâ‚‚ emissions as well as making India green energy hub

by following way:

(1) needle coke is main raw material for graphite electrode manufacturing. Graphite electrodes are used in electric arc furnaces (EAF) for steel making. In coming decades, more steelmaking capacity will be added through EAF route to reduce the COâ‚‚ emissions.

(2) The needle coke can be converted to anode materials for Li-ion batteries (LIB). So, this technology will make the prime raw materials (for EAF and LIB) available in India.

IMPACT:

New business of ₹ 3000-3500 Cr. for our company

This technology has potential to produce different carbon materials

It will accelerate green energy adoption in India (waste to wealth)