| OCR Text |
Show Petroleum industry heaters and boilers emit hazardous air pollutants that will be regulated under the M A C T and residual risk mandates of the Clean Air Act, as amended in 1990. Thus, it is clear that refiners will be obliged to install M A C T or more stringent technology to control air toxics from petroleum industry heaters and boilers. Refiners will, therefore, by force of events if for no other reason, utilize and benefit from the technology advancements, more economical approaches, and rational science- and risk-based regulations that arise from the collaborative R & D program that Petroleum Environmental Research Forum (PERF) Project No. 92-19 seeks to establish with the cooperation of the U.S. Department of Energy. Under section 112(e) of the Clean Air Act (CAA), as amended in 1990, EPA was required to publish a schedule for promulgating maximum achievable control technology ("MACT") emission standards i for any stationary source or group of stationary sources located within a contiguous area and under c o m m o n control that emits, in the aggregate, 10 tons per year or more of any hazardous air pollutant or 25 tons per year or more of any combination of hazardous air pollutants; or a lesser quantity based on the potency of the air pollutant, persistence, potential for bioaccumulation, other characteristics of the air pollutant, or other relevant factors. - The schedule for the initial promulgation of M A C T emission standards limiting toxic combustion byproducts from process heaters and industrial boilers is 11/15/00. 3 Furthermore, not later than 11/15/96, E P A is required to assess the risk to public health remaining [N.B., the "residual" risk] after compliance with the required emission standards. For sources emitting pollutants classified as known, probable or possible human carcinogens [N.B., such as petroleum industry heaters and boilers!, if compliance with the required standards does not reduce lifetime excess cancer risks to the most exposed individual to less than one in a million, E P A is required to promulgate more stringent standards. 4 The hydrocarbon combustion process actually manufactures air toxic byproducts. The following hazardous air pollutants, some of which are carcinogens (t) and none of which are originally present in the fuel, have been measured on gas-fired petroleum industry heaters and boilers 5 6 7: acenaphthalenc accnapthenc aceialdehydet anthracene benzenet benz(a )anthracenet ben7.o(a)pyrenet benzo( b)fl uoranthene t benzo(g.h,i)perylenc bcn7xxk)fluoranthenet chrysenet dibenz(a,h)anlhracenet ethylbenzene fl uoranthene Fluorene formaldchydet indeno( l,23-cd)pyrenet naphthalene phenanthrene phenol propylene pyrenet toluene xylene Furthermore, in the initial stages of P E R F Project No. 92-19 on Toxic Combustion Byproducts, computer simulations of the complex multiple-chain-branching combustion process produced, for pure methane, some 60 intermediate species in 250 reversible reaction steps and, for an 11-component hydrocarbon mixture representing refinery fuel gas, no less than 111 intermediate species in 637 reversible reaction steps. Thus, the foregoing table, doubtless incomplete, comes as no surprise. Virtually none of the combustion intermediates are present in the fuel initially I 1-3 |
