Ethylene process vent
Ethylene process vent means a gas stream with a flow rate greater than 0.005 standard cubic meters per minute containing greater than 20 parts per million by volume HAP that is continuously discharged during operation of an ethylene production unit. On and after July 6, 2023, ethylene process vent means a gas stream with a flow rate greater than 0.005 standard cubic meters per minute containing greater than 20 parts per million by volume HAP that is continuously or periodically discharged during operation of an ethylene production unit. Ethylene process vents are gas streams that are discharged to the atmosphere (or the point of entry into a control device, if any) either directly or after passing through one or more recovery devices. Ethylene process vents do not include:
(A) Pressure relief device discharges;
(B) Gaseous streams routed to a fuel gas system, including any flares using fuel gas, of which less than 50 percent of the fuel gas is derived from an ethylene production unit;
(C) Gaseous streams routed to a fuel gas system whereby any flares using fuel gas, of which 50 percent or more of the fuel gas is derived from an ethylene production unit, comply with § 63.1103(e)(4) beginning no later than the compliance dates specified in § 63.1102(c);
(D) Leaks from equipment regulated under this subpart;
(E) Episodic or nonroutine releases such as those associated with startup, shutdown, and malfunction until July 6, 2023;
(F) In situ sampling systems (online analyzers) until July 6, 2023; and
(G) Coke combustion emissions from decoking operations beginning no later than the compliance dates specified in § 63.1102(c).