Storage and Use of Hydrogen Fluoride at Petroleum Refineries

Safety Enhancements

Since 2015, a series of high-profile refinery explosions in California, Wisconsin, and Pennsylvania renewed the concern over using Hydrofluoric Acid (HF) and Modified Hydrofluoric Acid (MHF) in refinery operations, especially near densely populated urban centers. Regulatory agencies and local community groups have called on refiners to examine their options for mitigating the risks of aging HF alkylation units. 

The South Coast AQMD proposed to regulate the use and storage of HF by either adopting a rule or developing a MOU with the two petroleum refineries that use MHF in their alkylation process. Staff held a series of meeting beginning in 2017 to discuss the safety concerns and potential regulation of MHF. Presentations and documents from that effort can be found using the following link: 

Former Proposed Rule 1410 - Hydrogen Fluoride Storage and Use at Petroleum Refineries

On August 30, 2019, Torrance Refining Company and Valero Refinery submitted proffer letters committing to install significant voluntary enhancements in the alkylation unit at each of their refineries.  On September 6, 2019, the South Coast AQMD Governing Board approved Resolution 19 19 Accepting the Proffered Voluntary Implementation of Additional Safety Enhancements for the Use of MHF. The following link is the first annual report to the Refinery Committee on the progress of the implementation of new safety enhancements and control measures at Torrance Refining Company and Valero Refinery. The report includes the proffer letters, the South Coast AQMD request for quarterly reports on the progress of the safety enhancements, and the four quarterly reports submitted by the refineries.

Refinery Committee Report on Proffer Status - January 2021

Torrance Refining Company Quarterly Reports:

Valero Refinery Quarterly Reports:

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