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This paper aims to study the corrosion behaviour of copper alloys HSn70‐1 + As and B30 in water with sulphide.

The mass‐loss method, electrochemical tests and surface analysis were used to study the corrosion behaviour of copper alloys HSn70‐1 + As and B30 in water with sulphide.

Dezincification corrosion occurred on HSn70‐1 + As both in water with or without sulphide, and sulphide in water accelerated corrosion, while for the copper alloy B30, the corrosion rates were very small both in water with or without sulphide, although corrosion was also accelerated by sulphide in water.

In order to prevent copper alloys HSn70‐1 + As and B30 in water with sulphide from corroding, S²⁻ must be removed.

It was found that sulphide in water accelerated the corrosion of copper alloys HSn70‐1 + As and B30 in this paper. Therefore, when water containing sulphide is used as the source of make‐up water and cooling water, S²⁻ in water must be removed to prevent the pipelines and facilities from corroding. This means that the research results can offer theoretical guidelines for the prevention of pipelines and facilities in the power plant from corroding.

Investigates the application of the up‐flow anaerobic sludge bed (UASB) reactor for the anaerobic treatment of sewage sludge containing high concentrations of soluble and insoluble sulphides. Assesses the reactor’s performance in terms of volatile organic matter (VOM) and biogas production rate. The average percentage removal of VOM, total sulphide and biogas for the reactor operation without sulphide was 67 per cent, 65mgS/L and 1 L/day, respectively. The corresponding average percentage removal of VOM, total sulphide and biogas production rate for the experiment with 800mgS/L soluble sulphide was 45 per cent, 450mgS/L and 0.7L/day. Equilibrium concentrations of soluble sulphide up to 200mgS/L exert insignificant toxic effects, but toxicity increases as the concentration of soluble sulphide increases. A concentration of soluble sulphide of 1,200mgS/L produces severe toxic effects and the complete termination of gas production. An inhibitory concentration of sulphides affects gas production first, while significant volatile acid accumulation takes place much slower, and only after gas production has been severely retarded. Insoluble sulphide has an insignificant effect on the UASB up to a concentration of at least 800mgS/L. The addition of iron as ferric chloride prevents the toxicity of soluble sulphides as indicated by the minor effect on gas production. Therefore, the use of iron to precipitate sulphide could be used on a continuous basis to reduce sulphide toxicity.

The purpose of this paper is to develop an empirical equation of SRB corrosion based on their metabolic species.

Solution containing SRB metabolic species was simulated using abiotic chemistry approach. Linear polarization technique was used to measure the corrosion rate of X52‐sample in simulated solution containing SRB metabolic products species. The curve obtained from LPR data was then fitted using multiple non‐linear regression method by Minitab 15^® software.

Statistical analysis shows that sulphide and sulphite have significant effect on the X52 corrosion rate.

Using abiotic chemistry approach, an empirical equation that considers SRB metabolic species has been developed. The equation could be used to predict carbon steel corrosion rate by SRB.

Introduction It is well established that Si in silicon bronzes imparts high strength and corrosion resistance which are essential requirements for applications in hydraulic pressure lines, heat exchangers, propeller shafts, storage tanks and other equipments for chemical industries. They have high corrosion resistance towards marine environments, but possess inferior corrosion resistance in sulphide bearing atmosphere although more resistant to stress corrosion cracking and season cracking than brass on exposure to polluted atmospheres. In general, corrosion resistance of alloys depends on alloy chemistry, heat treatment schedule, presence of second phase, precipitation morphology and specific environment. However, studies on influence of heat treatment and variation of silicon content in (Binary) Cu‐Si alloys with particular reference to their corrosion resistance in chloride and sulphide bearing environments are scanty in literature. The present work has been designed to study the corrosion behaviour and to generate data on three types of commercially important Cu‐Si alloys in 3.5 per cent sodium chloride and 1 per cent sodium sulphide solutions.

About 50 epidemiological reports about possible associations between cancer morbidity and exposure to electromagnetic fields (EMFs) were published between 1979 and 1994. The majority of them (60‐75 per cent) documented a slight (1.5 to twofold) but significant increase in the incidence of certain rare forms of neoplasms (leukaemia, lymphoma, brain tumours). A limited support for carcinogenic potencies of EMFs is provided from cellular studies, but the effects appear to be generally weak, transient and difficult to replicate. Concludes that the available evidence associating cancer and EMF exposure is too tenuous to be convincing but too consistent to be ignored. Further progress needs better quantification of exposure levels and conditions, evaluation of dose‐effect relationships and liability to confounding carcinogenic factors that may influence morbidity rates in the investigated populations.

Certain previously unobserved features of scale formed in an oil‐fired billet reheating furnace are described. It is shown that sulphur‐rich melts formed at the scale/metal interface penetrate the grain boundaries of the overlying scale: subsequently the sulphur is removed by an oxidation reaction in which the surrounding manganese‐containing oxide takes part, to form a complex manganese silicate. The thermodynamics of possible reactions are discussed briefly and hypotheses put forward for the transport mechanisms of sulphur from the furnace atmosphere to the scale/metal interface.

Of the many unrelated types of microbes that can initiate or stimulate the corrosion of metals, the most important economically are the sulphate‐reducing bacteria. They flourish in the soil, in fresh and salt water (including heating and cooling systems) and in oil storage tanks and associated pipelines; and they have been found in all the continents including Antarctica.

Sulphides, in particular hydrogen sulphide, not only possess an unpleasant odour and are toxic, but also cause acute corrosion damage to municipal sewage systems and plants. The hydrogen peroxide waste water deodorization system introduced by Degussa AG of Frankfurt am Main, Federal Republic of Germany, oxidizes hydrogen sulphide and other sulphides to counteract odours and corrosion, the residual oxygen also preventing the renewed formation of hydrogen sulphide. If temporary oxygen deficiency should occur during biological treatment, more oxygen can be added simply and rapidly in the form of hydrogen peroxide. These processes are easily controlled, involve little investment and offer the advantage that pure water and oxygen are the only product remaining from reactions involving hydrogen peroxide.

Early this year (CORROSION TECHNOLOGY, March issue) we published the first part of a paper presented before the American Petroleum Institute's Refining Division and also the National Institute of Corrosion Engineers, describing the different forms of hydrogen damage and the prevention steps that were taken at the new fluid catalytic cracking unit of the Richfield Oil Corporation. At that time we announced that we hoped to publish more of this interesting paper, brought up to date. This, then, completes the work of Messrs. Neumaier and Schillmoller and describes protective steps that have been taken at the fluid unit gas plant, the evaluation of these steps, monitoring and the use of organic inhibitors.

The purpose of this paper is to evaluate the effect of seawater temperature on the corrosion behaviour of 90‐10 cupronickel alloys. Also, to investigate the effect of thiosulphate additions (one of the major sulphide oxidation products in seawater) on the alloy corrosion rate in seawater.

Potentiodynamic polarization measurement (DC) was used to estimate the corrosion rate of the cupronickel alloy in seawater with and without thiosulphate species (50‐650 ppm).

It was observed that the cupronickel alloy suffered accelerated corrosion as the seawater temperature was raised from 25 to 50 or 80°C. The increase in the corrosion rate was found to correspond well with the negative shift in the free corrosion potential. Thiosulphate addition was found to depend on the test temperature. At 25°C, thiosulphate activated the alloy dissolution rate and the higher were the thiosulphate concentrations, the higher was the corrosion rate. At 50 or 80°C, however, thiosulphate promoted the dissolution rate at early stages, but seemed to interfere with the surface film formation later on, producing a black film that effectively decreased the alloy corrosion rate. At higher potentials, however, the film became non‐protective, leading to accelerated corrosion once again.

This paper explains the corrosion behaviour of 90‐10 cupronickel alloys in seawater as a function of test temperature and thiosulphate additions.