The monthly weighted average residual organic HAP content of all grades of styrene butadiene rubber produced by the emulsion process, polybutadiene rubber and styrene butadiene rubber produced by the solution process, and ethylene-propylene rubber produced by the solution process that is processed, shall be measured after the stripping operation (or the reactor(s), if the plant has no stripper(s)), as specified in
§ 63.495(d), and shall not exceed the limits provided in
paragraphs (a)(1) through (3) of this section, as applicable. Owners or operators of these affected sources shall comply with the requirements of
paragraphs (a)(1) through (3) of this section using either stripping technology, or control or recovery devices. The organic HAP emissions from all back-end process operations at affected sources producing butyl rubber, epichlorohydrin elastomer, neoprene, and nitrile butadiene rubber shall not exceed the limits determined in accordance with
paragraph (a)(4) of this section, as applicable.
(4)
In addition to the requirements specified in
paragraph (a)(7) of this section, the organic HAP emissions from back-end processes at affected sources producing butyl rubber, epichlorohydrin elastomer, neoprene, and nitrile butadiene rubber shall not exceed the limits determined in accordance with
paragraphs (a)(4)(i) through (iv) of this section for any consecutive 12-month period. The specific limitation for each elastomer type shall be determined based on the calculation or the emissions level provided in
paragraphs (a)(4)(i) through (iv) of this section divided by the base year elastomer product that leaves the stripping operation (or the reactor(s), if the plant has no stripper(s)). The limitation shall be calculated and submitted in accordance with
§ 63.499(f)(1).
(i)
For butyl rubber, the organic HAP emission limitation shall be calculated using the following equation:
(ii)
For epichlorohydrin elastomer, the organic HAP emission limitation, in units of Mg organic HAP emissions per Mg of epichlorohydrin elastomer produced, shall be calculated by dividing 51 Mg/yr by the mass of epichlorohydrin elastomer produced in 2009, in Mg.
(iii)
For neoprene, the organic HAP emission limitation, in units of Mg organic HAP emissions per Mg of neoprene produced, shall be calculated by dividing 30 Mg/yr by the mass of neoprene produced in 2007, in Mg.
(iv)
For nitrile butadiene rubber, the organic HAP emission limitation, in units of Mg organic HAP emissions per Mg of nitrile butadiene rubber produced, shall be calculated by dividing 2.4 Mg/yr by the mass of nitrile butadiene rubber produced in 2009, in Mg.
(7)
For each affected source as described in
§ 63.480, beginning no later than the compliance dates specified in
§ 63.481(o), if the back-end process vent contains chloroprene such that it is considered to be in chloroprene service, as defined in
§ 63.482, then the owner or operator must comply with the requirements of
paragraphs (a)(7)(i) through (iii) of this section in addition to all other applicable requirements specified in
§ 63.483 and elsewhere in this section.
(i)
Reduce emissions of chloroprene by venting emissions through a closed vent system to a non-flare control device that reduces chloroprene by greater than or equal to 98 percent by weight, or to a concentration less than 1 ppmv for each process vent or to less than 5 pounds per year for all combined process vents within the process. If a combustion device is used, the chloroprene concentration of 1 ppmv must be corrected to 3 percent oxygen.
(ii)
To demonstrate compliance with the emission limits specified in
paragraph (a)(7)(i) of this section for back-end process vents in chloroprene service, owners and operators must meet the requirements specified in
§ 63.510.
(iii)
An owner or operator may designate a back-end process vent in chloroprene service as a maintenance vent if the vent is only used as a result of startup, shutdown, maintenance, or inspection of equipment where equipment is emptied, depressurized, degassed, or placed into service; however, owners and operators may not release more than 1.0 tons of chloroprene from all maintenance vents combined (i.e., including maintenance vents subject to this
paragraph (a)(7)(iii),
§ 63.485(z), or
§ 63.487(i)(4)) per any consecutive 12-month period. The owner or operator must keep monthly records of the quantity in tons of chloroprene released from each maintenance vent and include a description of the method used to estimate this quantity.