Paraffin deposits, productivity

The techniques of paraffin removal and paraffin prevention have been reviewed [810]. In particular, inhibitors for paraffin deposits are copolymers of ethylene with vinylacetate [525-527,1597] or polymers from p-nonylphenyl methacrylate and p-dodecylphenyl methacrylate [773]. These materials lower the pour point of the oil. It has been shown that for oils which differ in the content of n-paraffins and asphalt-resinous substances, it is necessary to use blends of copolymers of different compositions and molecular weights to obtain optimal efficiency. Polyacrylamide and wastes from the production of glycerol with a concentration of 400 mg/liter of oil have also been claimed to be effective as paraffin inhibitors [536]. 

S. D. Dzhanakhmedova, E. I. Pryanikov, S. A. Sulejmanova, K. K. Mamedov, E. G. Dubrovina, N. M. Indyukov, and A. B. Sulejmanov. Composition for preventing asphaltene-resin-paraffin deposits—contains waste from production of synthetic glycerine, in mixture with polyacrylamide. Patent SU 1761772-A, 1992. 

Mannich bases are present as auxiliaries and additives throughout the whole working process of the petroleum industry, from crude oil extraction up to the final products. Indeed, they are used as oleophilizers in drilling fluids- or in the treatment of cmde oil, such as desalting and prevention of paraffin deposits. Mannich bases and derivatives are, moreover, employed as antifoulants - in heat exchangers as well... 

Emulsions stabilized by paraffin are usually restricted to light crude oils in oil-field production. If paraffin deposition that restricts production is occurring upstream of an oil-treating facility, it may be feasible to apply a paraffin crystal modifier to the crude oil to prevent paraffin deposition and to eliminate paraffin as an emulsifying agent. A paraffin crystal modifier must enter an oil system at a temperature greater than the cloud point of the crude oil and upstream of the problem area. 

S Puskas, J Balazs, T Haraszti, L Turi, I Dekany. The influence of paraffinic deposits and their fractions on the stability of cmde oil emulsions. Petroleum abstracts 1st SPE Brazil Sect et al., Colloid Chemistry in Oil Production, Ash-phaltenes Wax Deposition International Symposium, Proceedings 230—235, Abstract no. 627, 639, Vol 36, no. 28, 1996. 

Caldas, J. N. (1997), Estudo Experimental e Modelagem Termodinamica da Floculagao dos Asfaltenos, PhD Thesis, COPPE/UFRJ, Rio de Janeiro Calemma, V. Iwanski, R Nali, M. Scotti, R. Montanari, L. (1995). Structural Characterization of Asphaltenes of Different Origins. Energy Fuels, 9, 225-230 Carnahan, N. F., (1989). Paraffin Deposition in Petroleum Production - Journal of Petroleum Technology, v 41,1024 1025... 

Uses Dispersant that penetrates, removes and prevents the redeposition of paraffin deposits, cleaning the production equipment of accumulations reduces the flow resistance of hydrocarbons in flowlines and pipelines under cold conditions Features Compatible with most other paraffin chemicals, additives and organic solvents typically used in the formulation of paraffin compds. 

While designing completion/workover fluids the main consideration is given to the effect of the fluids on well s productivity. Low production rates can be due to factors that are unrelated to the fluids introduced to the production zone. These would include poor or shallow perforations, cement filtrate invasion, paraffin wax deposition from crude oil, or movement of formation sand to block the well-bore. 

These metals permanently poison the FCC catalyst by lowering the catalyst activity, thereby reducing its ability to produce the desiretl products. Virtually all the metals in the FCC feed are deposited on the cracking catalyst. Paraffinic feeds tend to contain more nickel than vanadium. Each metal has negative effects. 

Ceresine is the white end-product of the purification of the fossil wax ozokerite, which is found in Miocene lignite deposits at considerable depths, by the separation of foreign and resinous matter and decolorisation by active agents. It is harder than paraffin wax, and has linear and cyclic hydrocarbons with high molecular weight [2]. It is used for waterproofing and oil absorption. 

Co/A1203 catalysts that contain higher amounts of less reactive polymeric carbon not only exhibited enhanced deactivation when tested in FTS when compared to the fresh catalyst, but also showed an increase in selectivity to olefinic products.31 The authors postulated that this was probably due to the reduction in hydrogenation ability of the carbon deposited catalyst to convert primarily formed olefins into the corresponding paraffins. 

C10-C14 long paraffin dehydrogenation is a key-step for linear alkyl benzene (LAB) production. However, this reaction, which requires monofunctional catalysis, is implemented on Pt-Sn catalysts deposited on controlled acidity alumina. It is generally associated with several secondary reactions, among which aromatic formation is extremely problematic it is catalyzed by a metallic phase (M) or by residual support (A) activity. Indeed, on the one hand, these arylaromatics are very good coke precursors and are consequently responsible for a large part of the... 

Paraffins function poorly as a solvent for some organic compounds. This fact can have various consequences. For example, gums, deposits, and fuel degradation products will not be dissolved or held in solution by high-paraffin-content fuels. As a result, gums and degradation products will fall from solution and settle onto fuel system parts such as storage tank bottoms and fuel system lines. The KB value for selected petroleum products is provided in TABLE 5-4. 

Several years ago, one of the authors found that nickel, platinum, and some other hydrogenating agents, when deposited on fresh synthetic silica-alumina cracking catalyst, made a new catalyst that would isomerize paraffin and naphthene hydrocarbons in the presence of hydrogen at elevated pressures and nominal temperatures. Table I shows some early typical results calculated from mass spectrometer analyses of the products obtained by passing methyl cyclopentane, cyclohexane, and n-hexane over a catalyst composed of 5% nickel in silica-alumina at the indicated reaction conditions. Isomerization of a number of other hydrocarbons has also been studied and reported elsewhere (2). 

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