The Central Pollution Control Board (CPCB) has issued Guidelines on Management of Pyro-metallurgical Slags (Iron & Steel Slags). This will be version 1.0 of these guidelines. This document was published in December 2023.
The NITI Aayog, the premier policy think tank of the Indian government, has classified pyro-metallurgical slags as “High Volume Low Effect Waste” (HVLE wastes) under the Hazardous and Other Wastes (Management and Transboundary Movement) Rules, 2016. The Committee on Circular Economy, constituted by NITI Aayog, has recommended promoting circular economy initiatives in the metal sector, with a specific action plan addressing the utilization of resource material from iron and steel slag.
To implement this action plan, Standard Operating Procedures (SOP) for the utilization of iron and steel slag, as stipulated under the Hazardous and Waste Management Rules 2016, have been issued. The guidelines aim to address the challenges posed by increased processing of iron concentrates and the constraints in handling large volumes of iron and steel slags.
The Indian Road Congress has also played a role in this initiative by publishing the “Guidelines for Use of Iron, Steel, and Copper Slag in Construction of Rural Roads – 2018,” providing detailed information on the engineering properties of these slags along with possible utilization options.
Furthermore, the Bureau of Indian Standards’ specifications on “Specifications of Coarse and Fine Aggregates for Concretes” permit the use of aggregates other than natural sources, including slags. The Central Road Research Institute, New Delhi (CSIR-CRRI), is actively working on revised guidelines for the utilization of steel slag in road construction based on research findings.
The guidelines for management of pyro-metallurgical slags from iron and steel plants stress the principles of resource efficiency, encouraging optimal use of primary resources in production. Steel plants are urged to set up facilities for internal recovery of material and ensure safe handling of slags, adhering to safety guidelines issued by the Ministry of Steel.
The guidelines provide a comprehensive approach to handling and managing slags, emphasizing environmental-friendly practices in collection, handling, storage, and transport to avoid water and air pollution. They mandate continuous improvement in environmental management and monitoring of groundwater quality around storage areas.
Iron and steel plants are encouraged to maximize internal use of slags, adopting appropriate cooling and treatment techniques. Unused slag is to be stored in captive storage yards with impermeable bases, and any unlined slag handling and storage areas must be discontinued within two years from the issuance of these guidelines.
The guidelines also outline specific areas where iron and steel slags can be used, such as cement production, aggregate in cement-concrete, and construction of roads and railways. Iron and Steel plants intending to use slag for other purposes are required to submit proposals to the Central Pollution Control Board (CPCB) through the respective State Pollution Control Boards (SPCB) or Pollution Control Committees (PCC).
Additionally, the guidelines set ambitious targets for iron and steel plants to achieve 100% regular utilization of iron and steel slags within specified timeframes. Annual reports on slag generation, storage, utilization, and disposal must be submitted to the CPCB by June 30 of the following year.
