New Delhi: The Coal India Limited (CIL) is all set to start commercial production of manufactured sand, also called M-sand, as a suitable and viable alternative to sand mined from rivers in a big way and earn handsome revenue.
Officials said the CIL is setting up M-sand production units at five plants, two in Western Coalfields Limited (WCL) and one each in the Central Coalfields Limited (CCL), South East Coalfields Limited (SECL) and Bharat Coking Coalfields Limited (BCCL) in the months to come. Out of the five proposed plants, Ballarpur Plant of WCL is expected to commence production by May 2023.
To expedite overburden of coal mines (OB) to sand initiative, CIL has prepared a model bid document for installing more such plants across subsidiaries in which terms and conditions have been modified for wider participation. The successful bidder shall have liberty to decide sale price and marketability of sand produced. Sand production expected from all these plants is 29 lakh cubic metre per annum by processing approximately 60 lakh cubic metre of OB.
In the absence of OB to sand initiative, WCL has sold 1,42,749 cubic metre of OB for road construction, formation for railways, land base levelling and other uses and earned ₹1.54 Cr. SECL has also used 14,10,000 cubic metre of OB for railway siding and FMC projects. Other subsidiaries of CIL are also taking similar initiatives to utilise OB for other purposes.
M-sand alternative to river sand
Sand is classified as a ‘minor mineral’, under the Mines and Minerals (Development and Regulations) Act, 1957 (MMDR Act) and administrative control over minor minerals vests with the state governments, and accordingly, regulated through state specific rules. Due to high demand, regulated supply and complete ban of sand mining during monsoon to protect river ecosystem, finding alternative to river sand became necessary. Sand Mining Framework (2018) prepared by ministry of mines envisages alternative sources of sand in the form of M-sand from crushed rock fines (crusher dust), sand from overburden of coal mines.
During opencast mining the overlying soil and rocks are removed as waste to extract coal and the fragmented rock (OB) is heaped in dumps. Most of the waste is disposed off at the surface, which occupies considerable land area and requires extensive planning and control to minimize the environmental impact of mining. The CIL has envisaged to process the overburden rocks for sand production in mines where OB material contain about 60% sandstone by volume which is harnessed through crushing and processing of OB.
OB to M-Sand initiative
OB to M-sand initiative of CIL is facilitating processing of waste overburden in its OC (open cast) mines. M-sand from overburden of coal mines have several benefits in terms of economy and environmental sustainability, including cost effectiveness and consistency. M-sand can be more cost-effective than using natural sand, as it can be produced in large quantities at a lower cost.
It can have a consistent grain size and shape, which can be beneficial for construction projects that require a specific type of sand.
Benefits of M-sand
Officials aid that M-sand can help to reduce the need for mining natural sand, which can have negative environmental impacts. Additionally, using the overburden from coal mines can help to repurpose materials that would otherwise be considered waste. Using manufactured sand can help to reduce the amount of water required for construction projects, as it does not require washing before use. M-sand is more angular and has a rougher surface, which makes it more workable for construction projects.
How M-sand project going to benefit coal companies?
Officials said that land occupied by OB dumps can be freed for alternative useful purposes. Recovery of sand from waste overburden is the best out of waste product. Commercial sale of produced sand can generate additional revenue for coal companies. Apart from commercial use, sand produced shall also be consumed for sand stowing in underground mines enhancing safety & conservation. Lesser sand extraction from river will reduce erosion of channel bed & banks and protect water habitat and help maintain water table.
Trial run emboldened bid to explore M-sand
The CIL has decided to go for processing of M-sand after its successful use in multiple projects. The processing of M-sand began at Bhanegaon and Gondegaon plants of WCL, Kajora area of ECL and Amlohri plant of the NCL. About 2.03 lakh cubic metre of M-sand produced at WCL plant was used in the construction of housing units under PM Awas Yojna in Nagpur. M-sand produced at other plants, which was low in quantity, were used in various smaller projects.