Petroleum treatment

Cycloversion A petroleum treatment process which combined catalytic reforming with hydrodesulfurization. The catalyst was bauxite. The process differed from the Houdry process in that the catalyst bed temperature was controlled by injecting an inert gas. Developed by the Phillips Petroleum Company and used in the United States in the 1940s. Pet. Refin., 1960, 39(9), 205. 

Catalysts for the Petroleum treatment processes, such as reforming and hydro-treating... 

In foregoing sections, we presented only the primary processes for petroleum treatment. It is important to note that all these processes are called primary processes because the petroleum only undergoes physical treatment. This means that chemical changes to the feed do not occur. All the processes we will describe in the sections of this chapter are referred to as secondary processes . This is intended to indicate that chemical changes of the feed occur during these treatments. 

We have concluded the discussion on the main petroleum treatment processes. However, after petroleum is treated using all the processes described in chapters 5 and 6, there is still a last operation to be performed. This is the blending of the product, from different units to produce market products. These are then delivered to gas stations and car services. 

Table 5.24 presents potential sources of emissions during refining and petrochemical processes involved in crude petroleum treatment and Table 5.25 shows an estimate of gaseous wastes from petroleum refining plants with a capacity of 2.5 x 10 t of raw petroleum (which is equivalent to 1000 MWj yr ). 

Table 6.24. Potential sources of emissions during refining and petrochemical processes involved in crude petroleum treatment...

Furthermore, molecular analysis is absolutely necessary for the petroleum industry in order to interpret the chemical processes being used and to evaluate the efficiency of treatments whether they be thermal or catalytic. This chapter will therefore present physical analytical methods used in the molecular characterization of petroleum. 

In the petroleum refining and natural gas treatment industries, mixtures of hydrocarbons are more often separated into their components or into narrower mixtures by chemical engineering operations that make use of phase equilibria between liquid and gas phases such as those mentioned below ... 

It should be noted that a capital allowance Is not a cashflow item, but is only calculated to enable the taxable income to be determined. The treatment of capital allowance for this purpose is a petroleum economics approach, which may differ from the accountant s view of depreciation when calculating net book values and profit. 

Groundwater. Spkls of refined petroleum product on land, and leaking underground storage tanks, sometimes contaminate groundwater. Bioremediation is becoming an increasingly popular treatment for such situations. 

The carboxylated units, ionized, decrease adsorption on subterranean substrates (23), ia proportion to the number of units, an important parameter ia petroleum recovery processes. In waste treatment processes cationic acrylamide comonomer units are often used (31) to iacrease adsorption and thereby flocculation of soHds ia wastewater (see Acrylamide POLYMERS Flocculating agents). The favorable and characteristics of acrylamide facilitate the... 

Thermal Cracking. In addition to the gases obtained by distillation of cmde petroleum, further highly volatile products result from the subsequent processing of naphtha and middle distillate to produce gasoline, as well as from hydrodesulfurization processes involving treatment of naphthas, distillates, and residual fuels (5,61), and from the coking or similar thermal treatment of vacuum gas oils and residual fuel oils (5). 

Petroleum. Apart from its use ia petrochemicals manufacture, there are a number of small, scattered uses of lime ia petroleum (qv) production. These are ia making red lime (drilling) muds, calcium-based lubricating grease, neutralization of organic sulfur compounds and waste acid effluents, water treatment ia water flooding (secondary oil recovery), and use of lime and pozzolans for cementing very deep oil wells. 

These are highly purified petroleum products which have been fully refined by either acid treatment or hydrogenation to remove all unsaturates, aromatics, and coloring materials to meet JnitedSfates Pharmacopoeia (USP) requirements. 

However, since the naphthalene produced from petroleum is of high purity and quaUty, the production of refined naphthalene by such chemical treatments essentially has ceased in the United States. Not only are such treatments expensive, but they also generate a significant amount of waste sludge, which creates additional costs for appropriate waste-disposal faciUties. 

Polymerization in Hquid monomer was pioneered by RexaH Dmg and Chemical and Phillips Petroleum (United States). In the RexaH process, Hquid propylene is polymerized in a stirred reactor to form a polymer slurry. This suspension is transferred to a cyclone to separate the polymer from gaseous monomer under atmospheric pressure. The gaseous monomer is then compressed, condensed, and recycled to the polymerizer (123). In the Phillips process, polymerization occurs in loop reactors, increasing the ratio of available heat-transfer surface to reactor volume (124). In both of these processes, high catalyst residues necessitate post-reactor treatment of the polymer. 

Alkali Treatment. Caustic washing is the treatment of materials, usually products from petroleum refining, with solutions of caustic soda. The process consists of mixing a water solution of lye (sodium hydroxide or caustic soda) with a petroleum fraction. The treatment is carried out as soon as possible after the petroleum fraction is distilled, since contact with air forms free sulfur, which is corrosive and difficult to remove. The lye reacts either with any hydrogen sulfide present to form sodium sulfide, which is soluble in water, or with mercaptans, foUowed by oxidation, to form the less nocuous disulfides. 

Acid Treatment. The treatment of petroleum products with acids has been in use for a considerable time in the petroleum industry. Various acids such as hydrofluoric acid, hydrochloric acid, nitric acid, and phosphoric acid have been used in addition to the most commonly used sulfuric acid, but in most instances there is Httie advantage in using any acid other than sulfuric. 

Solvent Treatment. Solvent processes can be divided into two main categories, solvent extraction and solvent dewaxing. The solvent used in the extraction processes include propane and cresyHc acid, 2,2 -dichlorodiethyl ether, phenol (qv), furfural, sulfur dioxide, benzene, and nitrobenzene. In the dewaxing process (28), the principal solvents are benzene, methyl ethyl ketone, methyl isobutyl ketone, propane, petroleum naphtha, ethylene dichloride, methylene chloride, sulfur dioxide, and iV-methylpyrroHdinone. 

---