Comments on the Proposed Increase in the Minimum Emission Standard (MES) for Sulphur Dioxide (SO2) Applicable to Coal-Fired Power Plant Stacks in South Africa

The report argues against doubling the SO2 emission limit, asserting that the government's rationale regarding water use and cost is flawed. It contends that Flue Gas Desulfurization (FGD) is more effective and not prohibitively water-intensive, while Dry Sorbent Injection (DSI) poses significant risks to particulate matter control, mercury emissions, and groundwater quality. The author recommends reducing the MES to 200 mg/Nm3 to align with international norms.

• The proposal to increase the SO2 limit from 500 mg/Nm3 to 1000 mg/Nm3 would effectively allow coal-fired boilers to emit double the previously allowed SO2 pollution, leading to adverse harm for exposed populations.
• The government's claim that FGD technology has high consumptive water needs is misleading; FGD water use is a small fraction of total consumptive water in thermal power plants, particularly those using water-based cooling cycles.
• Dry-FGD designs can achieve the 85% reductions required for the 500 mg/Nm3 standard and can even reach limits of 200 mg/Nm3, providing an alternative for water-stressed areas.
• Using DSI as a primary SO2 reduction technology would increase particulate matter (PM) loading on electrostatic precipitators (ESPs), potentially requiring expensive upgrades to maintain PM performance.
• DSI implementation can negatively impact air quality by increasing toxic mercury emissions, as it scavenges oxidizing agents that would otherwise form soluble oxidized mercury compounds.
• Sodium-based sorbents used in DSI increase the leachability of toxic metals, such as arsenic and selenium, into groundwater when spent sorbents are disposed of in ash landfills.
• The government's cost comparison is flawed; while DSI has lower initial capital costs, its operating costs are sizeable, and the capital costs for FGD may be inflated compared to recent applications in countries like India.
• The author recommends that the 2020 stack MES for coal-fired plants in South Africa be reduced to approximately 200 mg/Nm3, which is the norm in most other global jurisdictions.

APA

Sahu, R. (. (n.d.). Comments on the Proposed Increase in the Minimum Emission Standard (MES) for Sulphur Dioxide (SO2) Applicable to Coal-Fired Power Plant Stacks in South Africa. Centre for Environmental Rights. https://cer.org.za/wp-content/uploads/2019/07/Annexure-4_-Ron-Sahu_Report_on_MES_Increase_July-2019.pdf?x21779

Chicago

Sahu, Ranajit (Ron). Comments on the Proposed Increase in the Minimum Emission Standard (MES) for Sulphur Dioxide (SO2) Applicable to Coal-Fired Power Plant Stacks in South Africa. Centre for Environmental Rights, n.d. https://cer.org.za/wp-content/uploads/2019/07/Annexure-4_-Ron-Sahu_Report_on_MES_Increase_July-2019.pdf?x21779.

Wikipedia

{{cite report |last1=Sahu |first1=Ranajit (Ron) |title=Comments on the Proposed Increase in the Minimum Emission Standard (MES) for Sulphur Dioxide (SO2) Applicable to Coal-Fired Power Plant Stacks in South Africa |publisher=Centre for Environmental Rights |url=https://cer.org.za/wp-content/uploads/2019/07/Annexure-4_-Ron-Sahu_Report_on_MES_Increase_July-2019.pdf?x21779 |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{sahundcomments, author = {Sahu, Ranajit (Ron)}, title = {{Comments on the Proposed Increase in the Minimum Emission Standard (MES) for Sulphur Dioxide (SO2) Applicable to Coal-Fired Power Plant Stacks in South Africa}}, institution = {Centre for Environmental Rights}, url = {https://cer.org.za/wp-content/uploads/2019/07/Annexure-4_-Ron-Sahu_Report_on_MES_Increase_July-2019.pdf?x21779}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }