The ceramic industry is a major contributor to atmospheric pollution due to its high temperature processes, discharging sulfur dioxide (SO2) and nitrogen oxides (NOx). Monitoring authorities like CPCB and SPCB have set stringent standards to control emission of environmental pollutants and confirm industry compliance.

Understanding SO2 and NOx Standards for the Ceramic Industry

The ceramic industry encompasses various processes such as mixing, moulding, drying and firing, each of which contributes to the emission of particulate matter, SO2 and NOx. These emissions not only reduce air quality but also pose serious health hazards. To reduce these problems, the Central Pollution Control Board (CPCB) and State Pollution Control Boards (SPCBs) have enforced emission standards to control the release of pollutants into the environment. These standards differ as per the production capacity, fuel type and process alignment. Appropriate monitoring and compliance to these principles are essential for legal compliance, environmental sustainability, and maintaining the industry's social license to function. It is important for industry stakeholders to understand these standards to avoid penalties and contribute toward national control goals.

--------------Blog Contact Form-------------

What are the SO2 and NOx Standards for the Ceramic Industry?

The Central Pollution Control Board (CPCB) and State Pollution Control Boards (SPCBs) recommend SO2 and NOx emission limits for ceramic industries typically 100 mg/Nm³ for SO2 and 150 mg/Nm³ for NOx. Adherence needs clean fuels, control systems, and constant checking to standardize the discharge of environmental pollutants.

Emission of Pollutants in the Ceramic Industry

High- temperature kilns and fuel combustion in ceramic manufacturing result in the release of large environmental pollutants like SO2 and NOx. Major sources of emissions include raw material handling, fuel combustion and kiln operation.

• Fuel Combustion in Kilns: Most of the fossil fuels used are coal, pet coke and natural gas, which emit large amounts of SO2 and NOx due to the high sulfur and nitrogen content in the fuel used in several ceramic processes.
• Firing Process: The firing of ceramic materials at temperatures above 1000 °C results in thermal NOx formation, which contributes significantly to environmental air pollution levels, particularly in compactly populated areas.
• Raw Material Processing: Materials like Feldspar, kaolin and other clay may comprise sulfur compounds that discharge SO2 during high temperature processing steps, especially in early raw mix preparation.
• Spray Drying Operations: In tile manufacturing, spray dryer used for slurry drying add to NOx emissions due to high thermal energy inputs and combustion-based heating systems.
• Glazing and Decoration: Many glazing compounds and decorative materials used in small kilns or finishing ovens also produce minor emissions of SO2 and other pollutants during heat treatment.

Emission Standards for the Ceramic Industry

Under the Environment (Protection) Act, 1986, has outlines specific standards for limiting emissions of environmental pollutants from ceramic industries. These standards are implemented by SPCBs in different states.

Note:

• It is required to meet stack height criteria publication vide notification number G.S.R 475 (E), dated the 5th May, 1992 published in Gazette No. 202 dated 5th May 1992.
• It is required to meet stack height criteria publication vide notification number G.S.R. 742 (E), dated the 30th August,1990 published in Gazette No. 365 dated 30th August, 1990.
• It is required to meet stack height criteria publication vide notification number G.S.R 93 (E), dated 21st February, 1991 published in the Gazette No. 79 dated the 27th February, 1991.
• The lime kiln shall ensure that the minimum stack height is in accordance with Environment Protection Act, 1986 as amended from time to time and relevant direction of SPCBs / PCCs shall to adhere to. It shall be the concerned SPCB / PCC to increase the stake height, if required based on the scientific studies, keeping in view the habitations around such lime kilns.
• It is required to meet stack height criteria publication as prescribed by SPCBs/PCCs.

Also Read: What are the Standards for Emission or Discharge of Environmental Pollutants for Oil Drilling and Gas Extraction Industry

Implications for the Ceramic Industry

Compliance with SO2 and NOx standards has significant operational and financial implications for the ceramic industry. This needs technological upgradation, process optimization and regular monitoring.

• Need for Cleaner Fuels: To meet strict SO2 and NOx standards, many ceramic units are converting from coal or pet coke to PNG (piped natural gas) or biomass-based fuels, significantly mitigating emissions.
• Investment in Pollution Control Technologies: In several areas, installation of regular scrubbers, low-NOx burners and bag filters is now mandatory, resulting in capital expenditure and retrofitting costs.
• Operational Modifications: Industries should redesign kilns, regulate firing temperatures, reduce NOx formation, and alter residence times, all of which needs engineering inputs and energy efficiency optimization.
• Penalties and Legal Risks: Non-compliance with CPCB/SPCB emission standards may lead to monetary penalties, closure warnings and environmental litigation, which can disturb the license to operate the plant.
• Competitive Pressure: Adherence to pollution standards has helped the units gain recognition in export markets as it is highly necessary to adhere to global environmental standards and eco-certification.

Monitoring and Legal Compliance

Monitoring of emission is important for ceramic industries to adhere with CPCB and SPCB standards and compliance of CPCB and SPCB standards for the discharge of environmental pollutants. Periodic stack testing of SO2 and NOx is required to be conducted through NABL accredited laboratories. Moreover, industries situated in high pollution regions or operating on a large scale have to install Continuous Emission Monitoring System (CEMS), which conveys real-time data to the SPCB server. Form V is mandatory for annual submission of Environment Statement, which summarizes the pollutant discharge and control measures taken. The SPCB also orders third-party audits for verification, and industries are required to maintain Consent to Establish (CTE) and Consent to Operate (CTO) licence, which are dependent on demonstrated compliance.

Conclusion

Controlling SO2 and NOx emissions is both an environmental duty and a regulatory obligation for the ceramic industry. With defined CPCB and SPCB emission standards, manufacturers are expected to adopt cleaner fuel, install pollution control equipment and enforce real-time emission monitoring systems.

In addition, the adoption of pollution control measures has helped companies future-proof their operations against growing environmental regulations and public analysis. Consumers, investors and international customers support environmentally responsible manufacturers, pushing the industry towards more ecological practices. By guaranteeing compliance with emission norms, the ceramics sector not only reduces legal and environmental risks but also establishes itself as a major contributor to India's goals of improving air quality, mitigating pollution and reducing climate change.