Coastal Refinery

Figure 13 shows a fairly common setup for coastal refineries. 

In the event that there is too much residual oxygen in the deaerator effluent, the flow of vented steam from the top of the deaerator should be opened. However, often there is no vent valve, but just a fixed orifice vent. Or perhaps the supply steam control valve is 100 percent open. I had the latter problem at the Coastal Refinery in Aruba. The refinery was spending a small fortune on the oxygen scavenger chemical, pyridine. AUI did was to lower the deaerator set point pressure from 18 to 13 p>sig, and the residual oxygen in the effluent BFW dropped by an order of magnitude. 

Please do not think Tm making this story up. It s true. The location was the Coastal Refinery in Aruba. The engineer assigned to this project spent 85,000 for 16 new compressor valves for the reciprocating compressor. These valves had a somewhat smaller valve plate lift to accommodate the lower molecular gas. Of course, this sort of minor fine-tuning made no noticeable difference. Switching from 24 to... 

In the Coastal Refinery in Aruba, we used sieve trays with one-half-inch holes, which seemed to work fine. Avoid packed towers. They are subject to vapor-liquid channeling and poor fractionation efficiency due to sloppy installation, fouling, or poor liquid feed distribution. When calculating the required hole area for the trays, don t forget that the vapor loads and hence the required tray hole area will substantially diminish as the vapor flows up the column from the reboiler to the feed tray. This will normally require a reduction in the tray deck hole area in proportion to the reduced vapor flow rate. 

Figure 49.4 shows the overhead system of the Coastal Refinery crude distillation tower in Aruba. The island of Aruba is a beautiful country in the Caribbean Sea off the coast of Venezuela. 1 often take my wife, Liz, on a romantic vacation to this tropical paradise. During one such exotic trip I was assigned by Coastal to find a plan to improve fractionation between naphtha and jet fuel. The problem was that the naphtha contained 20 percent jet fuel. A computer simulation of the crude tower indicated that the apparent tray efficiency of the upper five trays was... 

I blocked valve C shown in Fig. 49.4, waited a few minutes, and obtained a sample of product naphtha from the hot drum. Lab analysis showed that the amount of jet fuel in the naphtha product had dropped from 20 to 10 percent. Another victory to report to the plant manager of the Coastal Refinery in Aruba. 

Unfortunately, Liz unfairly characterizes this visit to the Coastal Refinery in Aruba as just another business trip. She refuses... 

Unfortunately, Liz unfairly characterizes this visit to the Coastal Refinery in Aruba as just another business trip. She refuses to acknowledge that she had been taken to an exotic island paradise for a honeymoon vacation. She has persisted in this narrowminded view, disregarding the hundred or so trips we have made to the Aruba Refinery, all of which have been, in part, romantic adventures. 

The Coastal process uses steam pyrolysis of isobutane to produce propylene and isobutylene (as weH as other cracked products). It has been suggested that the reaction be carried out at high pressure, >1480 kPa ( 15 atm), to facHitate product separation. This process was commercialized in the late 1960s at Coastal s Corpus Christi refinery. 

Sulfur is a reactive, nonmetallic element naturally found in nature in a free or combined state. Large deposits of elemental sulfur are found in various parts of the world, with some of the largest being along the coastal plains of Louisiana. In its combined form, sulfur is naturally present in sulfide ores of metals such as iron, zinc, copper, and lead. It is also a constituent of natural gas and refinery gas streams in the form of hydrogen sulfide. Different processes have been developed for obtaining sulfur and sulfuric acid from these three sources. 

Crude oil is processed at oil refineries, generally located around coastal areas, and then transferred to a nationwide network of oil fuel terminals, from where it is distributed to customers. Road delivery vehicles, rail tank wagons or coastal tankers - depending on the location of the customer s storage installation - can make fuel supplies to the customer. 

On July 24,1994, an explosion followed by a number of fires occurred at 13 23 at the Texaco refinery in Milford Haven, Wales, England. Prior to this explosion, around 9 a.m., a severe coastal electrical storm caused plant disturbances that affected the vacuum distillation, alkylation, butamer, and FCC units. The explosion occurred due to a combination of failures in management, equipment, and control systems. Given its calculated TNT equivalent of at least 4 tons, significant portions of the refinery were damaged. That no fatalities occurred is attributed partially to the accident occurring on a Sunday, as well as the fortuitous location of those who were near the explosion. 

At present, 16 major refineries and 33 aboveground bulk liquid tank farms are situated on the Los Angeles coastal plain. The locations of these refineries and tank farms, and associated major pipeline corridors, are shown in Figure 12.24. 

Most of the PAHs in surface waters are believed to result from atmospheric deposition (Santodonato et al. 1981). However, for any given body of water, the major source of PAHs could vary. Jensen (1984) studied benzo[a]pyrene loading in a marine coastal area and determined that atmospheric deposition was indeed the major source of benzo[a]pyrene, with lesser amounts contributed by refinery effluent, municipal waste water, urban runoff, and rivers. Prahl et al. (1984) found that combustion-derived PAHs adsorbed to suspended sediments in rivers accounted for the major portion of PAHs in the waters of a Washington coastal area, and other studies have identified industrial effluents, road runoff, and oil spills as the major contributors in specific bodies of water (DeLeon et al. 1986 Santodonato et al. 1981). 

Coastal s production plan during the time period studied, which was July 1989 to July 1990, required the FCCU to make a minimum of 50% vol. cat gasoline. To achieve this when the refinery was not recycling demetallized catalyst required a continual makeup of 15 TPD of fresh catalyst, The refinery used 15 TPD of fresh catalyst between July 1989 and March 1990, which was immediately prior to the DEMET test run. They also used 15 TPD during the period of May 1990 to July 3990. which was the period after the test run. It was necessary for the refinery to maintain a constant calal y st inventory of 450 tons in the cat cracker and as they were adding 15 TPD and losing 3 TPD to their fine particulate col lection systems, it was necessary to withdraw 12 TPD of equilibrium catalyst. This catalyst was disposed of to landfill. The equilibrium catalyst contained 2,000 PPM of nickel and 450 PPM of vanadium. It had a surface area of about 128 nv/gm. 

Although refinery effluents generally contained the highest MTBE concentrations, discharges from WWTP accounted for the greatest proportion (78%) of the daily mass emission to bays and coastal waters in southern California [45]. 

During the past twenty five years acid rain, formally referred to as acid deposition, has been the focus of much political debate and scholarly research. Acid deposition occurs when important precursor pollutants, such as sulfur dioxide (SOj) and nitrogen oxides (NOx), chemically mix with water vapor and oxidants in the atmosphere and fall back to earth in wet or dry form. Wet deposition comes in the form of dew, fog, snow or rain, while dry deposition occurs as either gasses or dry particulates. Research has shown that acid deposition adversely affects freshwater lakes and streams, coastal habitats, agricultural production, forests, soils, human health and building materials. Fossil-fuel power plants, refineries, and paper and pulp mills are the major sources of SOj emissions, while automobiles and other vehicles are the primary emitters of NO. ... 

Wake, H. (2004). Oil refineries a review of their ecological impacts on the aquatic environment. Estuarine, Coastal and Shelf Science, vol. 62, p>p. 131-140. ISSN 0272-7714. 

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