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Show 3. NOx Regulation in Mexico. With a strong central government, Mexico has done what the USA could not: adopt a comprehensive countrywide regulation which establishes different NOx limits to regions with different levels of industrial activity and fuel availability. There is also a central authority to enforce this law, with offices in every state of the country and an ever increasing army of inspectors: The Ministry of Ecology and Social Development (SEDESOL). Mexico faces an enormous limitation in her fight to reduce emissions from stationary industrial sources: the lack of clean fuels in most parts of the country. Although the country is rich in oil reserves, most of Mexico's oil is of poor quality, very heavy and with a high sulfur content. Gas fields are practically non-existent outside the oilrich southern states. Associated Natural Gas from these oil field, which is not abundant to start with, cannot be distributed to_ most cities north of Mexico City for lack of an adequate distribution network. In addition to the above, mexican refineries are inefficient and insufficient to deliver the large amounts of distilled oils required for a serious emission reduction program. As a result, an estimated 70% of the industrial steam generation in the country is heavy oil fired. Typical mexican #6 oil contains around 4% sulfur, 0.4% Nitrogen, 0.1 % Ash and 8-12% Conradson Carbon. Early Regulations. The first set of regulations effectively limiting emISSIons from stationary sources were promulgated in October 1988, although serious efforts to enforce them were not evident until after 1990. The so-called "Technical-Ecological Norms" established limits for NOx, CO, SOx and Solid Particulate emissions from units firing Diesel Oil (CCAT -005/88), Heavy Oil (CCA T- 007/88) and Natural Gas (CCAT-008/98). More th.an seek a reversal of air pollution trends, these norms were clearly meant as a preparation and awareness building phase for the more restrictive standards to come. Unilaterally developed by Page 4 SEDESOL without consultation with industry organizations, the limits imposed by these regulations were in fact a copy of Publication AP-42 of the US EPA, an early compilation of typical uncontrolled emissions for different types of equipment and fuels. As a result, the NOx limits imposed were quite relaxed and in most cases all it took was a good boiler tuning to comply with them. They did not promote fuel substitution but in fact imposed a penalty on natural gas firing, which was twice as expensive as heavy oil at the time. The remarkable exception were CO limits which were set at around 50 ppm for all units. This was a particular difficult limit to meet for many existing units which had been subject to less than desirable maintenance during the 80's, a decade of deep economic troubles for the country as a whole. The NOx limits imposed by this first regulation ranged from 0.16 to 0.18 LblMM BTU for diesel oil firing, 0.37 to 0.45 LblMM BTU for heavy oil firing and 0.14 to 0.56 LblMM BTU for Natural firing. Official NOlm NOM-PA-CCAT-019/93.Emission limits for Solid Particulate, Carbon Monoxide, Nitrogen Oxides, Sulfur Oxides and Smoke from stationary sources. The current regulation, called "Mexican Official Norm NOM-PA-CCAT-019/93", was promulgated in April 1993 and is the result of a long negotiation process between SEDESOL, industry organizations and PE~X, mexico's oil monopoly. Reflecting pressure from the industry, the NOx limits are less restrictive than those originally proposed by SEDESOL. On the other hand, reflecting the struggle of PE~X to keep with the demand for natural gas, this regulation maintains different limits for gas and liquid fuels. This distinction did not exist on SEDESOL's original proposal. As shown in Figure 3.1, different NOx limits apply to different areas of the country. The most restrictive limits apply to the Mexico City area, which houses around 25% of the country's |