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GERMANY Inhibitors in oil refining. Anodic inhibitors of practical importance are chromates and nitrites, especially with water of low oxygen content. Cathodic inhibitors are useful when hard water is to be treated, and glassy phosphates and calcium bicarbonate have rendered useful service. Of the organic inhibitors, sodium benzoate and organic amines are promising. It is, however, considered wiser not to use inhibitors if they are unsuitable or offer insufficient protection.—(P. W. Sherwood, Werkstoffe & Korrosion, 1955, 6, 2–6.)

High‐temperature corrosion by H2S is a new problem in refinery technology. It is associated with catalytic reforming and desulphurisation processes which were introduced during the last 5–7 years.

Protection from corrosion by water is the most important single item of preventive maintenance in petroleum refineries. This problem is encountered in innumerable forms and no one solution satisfies all the requirements of even a single refinery, let alone the needs of different plants. The broad field of protection from water corrosion takes in such widely differing situations as underground storage tanks which are to be spared attack from soil water, prevention of corrosion in heat exchangers due to sweet or brackish cooling water, and in steam boilers due to softened water, and protection of exposed metallic structures from rain water, etc.

The petroleum industry has been quick to appreciate the possibilities of plastics pipe for handling corrosive fluids and gases, and is now using it in considerable quantities for a variety of applications, including the carrying of corrosive chemicals in refinery and petrochemical plant. From a research engineer in America comes the article below reviewing the main types of pipe materials available for such purposes, special attention being paid to the suitability of their properties for specific types of applications. Also included are hints regarding the installation of pipework.

Bacterial action often constitutes a major cause of corrosion in petroleum refineries and similar plant. The problem occurs in three major areas: in underground structures, in cooling water systems and in storage facilities for both crude and refined petroleum products. What are the factors upon which bacterial corrosion depends and what are the remedies?

Direct costs associated with corrosion in U.S. refining operations today average between 14 and 18 cents per barrel of crude oil. Altogether, the annual toll taken by corrosion in the U.S. refining industry alone is well over $400 million. In this article, the author considers which items in the running and maintenance of a refinery can be directly attributed to corrosion and its prevention. Causes contributing to the severity of corrosion are also considered, and means for its control.

Considerable headway is being made in the acceptance of non‐destructive testing methods for refinery construction and maintenance. If properly used, these techniques constitute a valuable tool for determining the quality of workmanship (in acceptance tests of refinery equipment) and the survival outlook of installed equipment which may be exposed to mechanical wear, erosion or corrosion. They find further application in locating obstructions which may form in pipelines or other equipment.

Corrosion is a major cause of refinery tank failure. Its cost can be minimised by three measures: cathodic protection ; protection by painting or lining under a well‐planned schedule; or removal of the tank from service as soon as it has ended its useful life. The objective must be to incur the minimum overall cost, and the best solution is often a combination of these measures. Though costs and conditions mentioned pertain to the U.S.A., the conclusions in the main are the same elsewhere.

Corrosion is an electrolytic phenomenon. The corroding metal is at higher potential than its surroundings. Accordingly, there will be a flow of electricity away from the metal, leaving the metal in an ionised (oxidised) state. Chemical combination with oxygen from the surroundings must occur simultaneously for electrical balance.

THE Report of the Committee on Libraries, which was issued by the University Grants Committee in the summer of 1967, had for long been called the Parry Report after its Chairman, Dr. Thomas Parry, formerly Librarian of the National Library of Wales and at the time the Principal of University College of Wales in Aberystwyth. When it was first set up in June 1963 the terms of reference were as follows: