11 INDUSTRIAL PLANTS FOR THE EXTRACTION AND PRODUCTION OF ETHANE, ETHYLENE AND LIQUEFIED PETROLEUM GAS (LPG) COMPRISED OF DISTILLATION TOWERS, WASH TOWERS, EVAPORATOR TOWERS, EXTRACTION TOWERS, DEGASSING TOWERS, FLASH TOWERS, FRACTIONATING TOWERS, BUBBLE TOWERS, SCRUBBER TOWERS, STRIPPING TOWERS, RECTIFICATION TOWERS, CATALYTIC TOWERS, SPRAY TOWERS, PACKED TOWERS, TOPPING AND FRACTIONATING TOWERS, DEBUTANIZER TOWERS, DEPROPANIZER TOWERS AND VACUUM TOWERS; COLUMNS; NAMELY, ABSORPTION COLUMNS, BAFFLE COLUMNS; HYDROGENATING PLANTS, CRACKING PLANTS, GASOLINE PLANTS, DEWAXING PLANTS, DESULFURIZING PLANTS, SWEETENING PLANTS; BOILERS, HEAT EXCHANGERS, REHEATERS, FLASH BOILERS, STEAM BOILERS, FURNACES, CHIMNEYS, STACKS, CATALYTIC AND CHEMICAL REACTORS