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The purpose of this paper is to study the corrosion process by examining the deterioration of X80 steel exposed to a real petroleum sample containing condensed hydrocarbon plus oilfield-produced water, which were subjected to stimulated emulsions in flowing media at 50°C.

The impedance and polarization spectra were used to assess the aggressiveness of the petroleum sample and tried to find a washing process using condensed hydrocarbon with deionized water. Mössbauer technique was used to identify the phases in precipitated ions obtained during an oven-drying procedure of the oilfield produced water.

The emulsion, chloride, sulphur compounds, heavy metals and the use of a double hydrodynamic system were the most important factors affecting the corrosion of X80 steel. The corrosion rate of this steel increased when oilfield-produced water was stimulated by a double hydrodynamic system (4.56 mm/year). It was determined to be 7.66 mm/year and 4.01 mm/year when steel was exposed to a stimulated emulsion using the petroleum sample and condensed hydrocarbon with deionized water at 24 h, respectively, suggesting that a significant process of hydrocarbon washing could occur and a more corrosive solution was highlighted. Mössbauer results showed that the ions precipitates included the following phases at Wt.%: magnetite (20.0), greigeite (22.8), siderite (3.2), pyrite (2.9), marcasite (26.7) and mackinawite (24.4).

A stimulated hydrocarbon/water emulsions with a more homogeneous solution containing high concentrations of saline compounds and heavy metals were used to simulate the susceptibility to corrosion on the internal pipeline steels exposed to any type of immiscible liquids such as condensed hydrocarbon, or crude oil, containing water. A practical application of the presented research could provide a novel framework for understanding the internal corrosion in pipelines from the simulation of washed hydrocarbons after the stimulated emulsions that can be found in the field. Because more susceptibility to corrosion for pipeline steels would be expected at the end of the transportation of the fluid. It is possible to investigate the possible corrosion mechanisms by using a dried oilfield-produced water sample interacting with the pipeline steels.

Purpose – This work aims to study the treatment of adsorbant on the increasing liquid hydrocarbon quality produced by pyrolysis low density polyethylene (LDPE) plastic waste at low temperature. The hydrocarbon distribution, physicochemical properties and emission test were also studied due to its application in internal combustion engine. This research uses pure Calcium carbonate (CaCO₃) and pure activated carbon as adsorbant, LDPE type clear plastic samples with control variable that is solar gas station.

Design/Methodology/Approach – LDPE plastic waste of 10 kg were vaporized in the thermal cracking batch reactor using LPG 12 kg as fuel at range temperature from 100 to 300°C and condensed into liquid hydrocarbon. Furthermore, this product was treated with the mixed CaCO₃ and activated carbon as adsorbants to decrease contaminant material.

Findings – GC-MS identified the presence of carbon chain in the range of C6–C44 with 24.24% of hydrocarbon compounds in the liquid. They are similar to diesel (C6–C14). The 30% of liquid yields were found at operating temperature of 300°C. The calorific value of liquid was 46.021 MJ/Kg. This value was 5.07% higher than diesel as control.

Originality/Value – Hydrocarbon compounds in liquid produced by thermal cracking at a low temperature was similar to liquid from a catalytic process.

Sour water condensates are aqueous condensates which contain different concentrations of aggressive compounds such as HCl, H2S, CO2, NH3, cyanides, etc. These condensates which can be fairly corrosive are encountered in a variety of refinery processes ranging from atmospheric distillation units to hydrodesulphurisers and sour water strippers. This paper deals with the mechanism of corrosion by these condensates and the factors influencing corrosion in several typical refinery units. In addition, methods for corrosion prevention and control are also discussed.

The mechanical properties of carbon and graphite as structural materials have been improved considerably since the 1940s, and graphite equipment is widely used in chemical and other plant. Here is part of a talk given at the recent British industrial exhibition in Moscow by Dennis Hills, sales director of Powell Duffryn Chemical Engineering Ltd., who have specialised in carbon/graphite equipment under the trade name Delanium.

The objective of this paper is to measure the differences in heat transfer properties of refined hydrocarbon distillate fractions that are commonly used as base oils in aluminium sheet cold rolling applications and assess if the heat transfer coefficient (HTC) values for these oils can be predicted from their compositions. The composition and physical properties of these fluids affect their tribological behaviour by influencing hydrodynamic lubrication, wear debris removal and cooling.

A purpose-built test rig was used to measure HTCs for a wide range of hydrocarbon solvents used as aluminium cold rolling oils. The results are expressed in the form of the HTCs relative to those of 14- to 16-carbon-chain-length normal paraffins. Measured HTC values were compared to values calculated from oil compositions and from the thermal conductivities of compounds representing different classes of typical oil components.

There were significant differences between the heat transfer properties of various hydrocarbon solvents, and these differences could be estimated from their content of normal and simple iso-paraffins and heavily branched and cyclic hydrocarbons. The HTC of hydrocarbon mixtures increases with the increasing content of n-paraffinic compounds.

This paper shows how one can estimate the relative HTCs of oils of known compositions, based on the relative thermal conductivities of model compounds. This is relevant to prediction of cooling properties of aluminium cold rolling base oils.

CO₂ corrosion rate prediction is regarded as the backbone of materials selection in upstream hydrocarbon industry. This study aims to identify common types of errors in CO₂ rate calculation and to give guidelines on how to avoid them.

For the purpose of this study, 15 different “corrosion study and materials selection reports” carried out previously in upstream hydrocarbon industry were selected, and their predicted CO₂ corrosion rates were evaluated using various corrosion models. Errors captured in the original materials selection reports were categorized based on their type and nature.

The errors identified in the present study are classified into the following four main types: using inadequate or false data as the input to the model, failing to address factors which may have significant influence on corrosion rate, utilizing corrosion models beyond their validity range and utilizing a corrosion model for a specific set of input, where the model is considered to be inaccurate even though the input lies within the software’s range of validity.

This study is mainly based on the use of various corrosion models, and except few cases for which some actual field corrosion monitoring data were available, no laboratory tests were performed to verify the predicted data.

The paper provides a checklist of common types of errors in CO₂ corrosion rate prediction and the guidelines on how to avoid them.

CO₂ corrosion rate calculation is regarded as the backbone of materials selection in hydrocarbon industry. In this work, the source of errors in terms of corrosion modeling tool and human factors were identified.

TO answer the question, “What are the best fuels for aircraft?” might seem at first sight neither more nor less difficult than to say, What are the best fuels for motor cars? There is, however, one added factor, namely, that of weight, and this adds greatly to the complexity of the question.

Government appointed and sponsored committees of every description—select, ad hoc, advisory, inquiry—such a prominent feature of the public scene since the last War, are understandable, even acceptable, reflect the urgency of the times in which we live. In the gathering gloom of more recent twilight years, they have flourished inordinately, especially in the socio‐political field, where most of their researches have been conducted. Usually embellished with the name of the figure‐head chairman, almost always expensively financed, they have one thing in common—an enormous output of words, telling us much of what we already know. So much of it seems dull, meaningless jargon, reflecting attitudes rather than sound, general principles.

The success of vapour phase soldering for electronic assemblies has led to the availability of several heat transfer fluids for the purpose. This paper aims to demonstrate the significance of the differing properties of fluids, illustrated by measurements on the three most commonly used in the UK. These three, as well as any future fluids, can be judged in terms of (i) vapour temperature and its influence on soldering yields and materials properties; (ii) stability of soldering temperature with time; (iii) heat transfer efficiency; (iv) power requirements and thermal control; (v) rosin solubility and flux wash‐off; (vi) toxicity, especially under thermal stress; (vii) corrosivity and its dependence on process control; and (viii) consumption of fluid.

This paper aims to establish the acid concentration of finely dispersed droplets in hydrocarbon oils. Small quantities of aqueous sulphuric acid (H₂SO₄) were found to be trapped within hydrocarbon shells, making them inaccessible for concentration evaluation by titration.

Fourier transform infrared spectroscopy (FTIR) used in the attenuated total reflection mode (ATR; FTIR-ATR) was applied to study the reaction products of squalane, C₃₀H₆₂, and an API Group I base oil with various concentrations of aqueous H₂SO₄.

The absorbance comparison usually used for estimating acid concentrations was found to fail when small quantities of acid are trapped in the reaction product. It was found that the peak shift and changes in absorbance found for various pure aqueous acid concentrations were useful to establish the remaining concentration of the trapped H₂SO₄.

This paper fulfils the identified need to study acid dissociation-dependent peak shifts of H₂SO₄ to find the acid concentration of finely dispersed droplets in hydrocarbon oils.