Paste fill technology for future underground mining
South Eastern Coalfields Limited (SECL) is set to become the first coal PSU in India to adopt paste fill technology for coal mining—marking a major step toward sustainable and environmentally friendly mining practices.
To implement this innovative underground mining technology, SECL has signed a Rs.7,040 crore agreement with TMC Mineral Resources Private Limited.
The project, a major initiative to promote green mining technologies in India, aims to enhance coal production while significantly reducing environmental impact.
Under this agreement, large-scale coal production will be undertaken using paste fill technology in the Singhali underground coal mine located in SECL’s Korba area. Over a period of 25 years, the project is expected to produce approximately 8.4 million tonnes (84.5 lakh tonnes) of coal http://coal.nic.in.
Paste filling is a modern underground mining method that eliminates the need to acquire surface land. After coal extraction, the mined-out voids are filled with a specially prepared paste made from fly ash, crushed overburden from opencast mines, cement, water, and binding chemicals. This process prevents land subsidence and ensures the structural stability of the mine.
Importantly, the paste utilizes industrial waste materials, making the process environmentally sustainable and promoting waste recycling https://www.iea.org/.
The Singhali underground mine was approved in 1989 for a production capacity of 0.24 million tonnes per year and commenced operations in 1993. Presently, the mine has 8.45 million tonnes of extractable reserves of G-7 grade non-coking coal. It was developed using the Bord and Pillar method, employing Load Haul Dumpers (LHDs) and Universal Drilling Machines (UDMs) for underground operations.
However, the surface area above the mine is densely occupied—with villages, high-tension electricity lines, and a Public Works Department (PWD) road—rendering traditional caving methods unfeasible due to safety and environmental concerns.
With the introduction of paste fill technology, mining activities in this area can now proceed without disturbing the surface infrastructure.
The successful implementation of this technology in Singhali is expected to pave the way for resuming operations in other underground mines where similar land constraints exist.
Speaking on the occasion, SECL CMD Harish Duhan said on 18 April, “I firmly believe that paste fill technology will not only secure the future of underground mining but also offer an innovative, eco-friendly solution. This project is a landmark step toward green mining and will shape the future of the coal industry in the years to come.” Fiinews.com
