On Sept. 8, 2021, the United States Environmental Protection Agency (EPA) issued an Advance Notice of Proposed Rulemaking (“ANPRM Notice”) addressing possible future regulation of pyrolysis and gasification units under the federal Clean Air Act (CAA).

Pyrolysis and gasifying can promote a “circular economy” for plastics, where post-consumer plastic products can be recycled to produce a plastic of equal or similar quality rather than being discarded. Both pyrolysis and gasification can convert solid or semi-solid feedstocks into useful products such as energy, fuels, and chemical commodities.

Potentially regulated entities include the manufacturers of the following products: wood, pulp, paper, paperboard, furniture, chemicals and allied products, plastics and rubber products, cement, nonmetallic mineral products, and fishing operations. Additional regulated entities include solid waste combustion units decomposing municipal solid waste, oil and gas exploration operations, mining operators, pipeline operators, utility providers, private hospitals and health care facilities including commercial research companies, and commercial waste disposal companies.

Many existing operations that incorporate pyrolysis and gasification have been regulated by the EPA under Section 129 of the CAA, which imposes certain emissions guidelines and performance standards for the various types of solid waste incinerators. But pyrolysis and gasification have been inconsistently defined and managed under the existing Section 129 rules. Therefore, the EPA published its ANPRM Notice because it believes “there is considerable confusion in the regulated community regarding the applicability of CAA Section 129 to pyrolysis and gasification units.”

The EPA set Nov. 8, 2021, as the deadline to submit public comments. Because the ANPRM Notice could lead to new rules for pyrolysis and gasification units as well as to changes in pending and existing Section 129 rules, industries that use pyrolysis or gasification should consider submitting comments to the EPA prior to the deadline.