Chapter 3 INHALATION HAZARDS IN REFINERIES INTRODUCTION Operations of the petroleum industry can logically be divided into production, refining, and marketing. Production includes locating and drilling oil wells, pumping and pretreating the crude oil, recovering gas condensate, and shipping these raw products to the refinery or, in the case of gas, to commercial sales outlets. Refining, which extends to the conversion of crude to a finished salable product, includes oil refining and the manufacture of various chemicals derived from petroleum. The chemical manufacturing segment is referred to as the petrochemical industry. Marketing involves the distribution and the actual sale of the finished. | Chapter 3 INHALATION HAZARDS IN REFINERIES INTRODUCTION Operations of the petroleum industry can logically be divided into production refining and marketing. Production includes locating and drilling oil wells pumping and pretreating the crude oil recovering gas condensate and shipping these raw products to the refinery or in the case of gas to commercial sales outlets. Refining which extends to the conversion of crude to a finished salable product includes oil refining and the manufacture of various chemicals derived from petroleum. The chemical manufacturing segment is referred to as the petrochemical industry. Marketing involves the distribution and the actual sale of the finished products. To prevent unsafe operating pressures in process units during shutdowns and startups and to handle miscellaneous hydrocarbon leaks a refinery must provide a means of venting hydrocarbon vapors safely. Either a properly sized elevated flare using steam injection or a series of venturi burners actuated by pressure increases is generally considered satisfactory although there is less of a tendency to rely on flaring practices in the United States today. Good instrumentation and properly balanced steam-to-hydrocarbon ratios are prime factors in the design of a safe smokeless flare. Refinery operations are complex systems involving many unit operations ranging from high pressure systems wide temperature variations and products and intermediates that vary from toxic to highly flammable. There are numerous dangers associated with inhalation hazards chemical exposure by workers and fire and explosion. This chapter provides an overview of the basic operations of a refinery and the hazards associated during operation and emergency situations along with standard safety precautions and designs. It is important to note that no two refineries are exactly alike. Designs and the sequential use of certain equipment can vary significantly and hence the operation and specific safety .