Over the past few months, South Coast Air Quality Management District (SCAQMD) requested certain facilities complete a voluntary survey. This comprehensive survey asked hundreds of facilities to provide information about their combustion equipment, such as equipment rating and currently permitted emission limits. Some of the targeted equipment included, but was not limited to: ovens, dryers, heaters, furnaces, kilns, afterburners, oxidizers, crematories, metal heating furnaces (aging, billet, forging), and metal melting furnaces (crucible and pit, kettle and pot, rotary).
Current emission limits for these combustion sources range anywhere between 30 - 60 ppm NOx. SCAQMD has completed their initial technology assessment, which used the survey responses to assess where facilities would stand against proposed control technologies and emission limits. The proposed draft emission limits for these units are being reduced to 5 - 30 ppm NOx. Emission limits will be split among the following rules:
- Rule 1147 - NOx Reductions from Miscellaneous Sources [Amended]
- Rule 1147.1 - NOx Reductions from Large Miscellaneous Combustion [New]
- Rule 1147.2 - NOx Reductions from Metal Melting and Heating Furnaces [New]
Following confirmation from SCAQMD's cost effective analysis, these new emission limits will likely need to be met by installation of low NOx burners (LNB), ultra-low NOx burners (ULNB), or selective catalytic reduction (SCR). While the amendments to Rule 1147 are driven in part by the sunsetting of the Regional Clean Air Incentives Market (RECLAIM) program, non-RECLAIM facilities will also be subject to the new emission limits. Similar to the Rule 1146 amendments in December 2018, once the Rule 1147 series emission limits are formalized and adopted, subject facilities may be required to install the above, restrict fuel usage, or replace the unit all together.
Although draft rule language is not currently available at the time of this article, SCAQMD is scheduled to adopt the new and amended rules in August 2020. Facilities should be conscious of these new emission limits, and the potential capital projects that come along with them. If the compliance schedule follows a similar timeline to that of Rule 1146, these emission limits could be in full effect by August 2021.