Review of material selection and corrosion in seawater reverse osmosis desalination plants

Abstract

ab s t r ac tSeawater desalination infrastructures require a careful material selection with high corrosion resistance. The high seawater temperatures in warm regions, where many desalination plants are developed, must be clearly considered regarding the corrosion of materials. To comply with the operational characteristics of seawater reverse osmosis (SWRO) process (high pressure, high chloride content and dissolved oxygen content at saturation values), the conventional material selection was stainless steel with sufficient pitting resistant equivalent number. However, many cases of corrosion failures of stainless steel in SWRO desalination units have been reported. In most cases the cause of the failures was attributed to the use of not enough alloyed grades. However, high alloy stainless steels are also susceptible to crevice and pitting corrosion in seawater. The operational corrosion risk will highly depend on the stainless steel composition, on the metallurgy (i.e. cast or wrought), on the service conditions, and on the geometrical configuration of the confined zones in contact with seawater. The present paper reviews the corrosion performance of metallic materials used for SWRO desalination plants. It focuses on the corrosion behaviour of several stainless steel grades. Recent corrosion failures of stainless steel pumps used in SWRO desalination plant in the Mediterranean Sea are also discussed.

Extremely durable biofouling-resistant metallic surfaces based on electrodeposited nanoporous tungstite films on steel

“…We demonstrate that our omniphobic-slippery TO coatings are able to retain their morphology and wetting characteristics under high-friction conditions and, at the same time, to completely repel blood and significantly reduce attachment of Escherichia coli to medical-grade steel devices. Furthermore, when this coating is constructed on an austenitic-grade stainless steel, a commonly used steel in marine environment 42 , the omniphobic-slippery TO films almost completely repel algae fouling without showing any sign of morphology degradation or environmental toxicity.…”

The Impact of Corrosion Inhibitors in Desalination Systems

“…Ionic liquids (ILs) are likely to get the attention of many researchers for their potential application as corrosion inhibitors in a variety of industries due to their low toxicity and outstanding efficacy. , The ionic liquids’ alkyl chain length significantly affects the rate of corrosion. The performance of ILs’ ability to inhibit corrosion is improved by an increase in the metal surface coverage brought on by an increase in the alkyl chain lengths of ILs. , …”

“…For instance, the ambient seawater temperature in the Middle East is often above 30 °C, which greatly increases the likelihood of crevice and pitting corrosion, unlike places where the saltwater is below 20 °C in temperature. 30 3.3. pH. Corrosion rates can be influenced by the pH and alkalinity of desalinated water.…”

“…Desalination system corrosion can have a number of harmful effects: − Decreased Efficiency: Corroded parts can impair the desalination system’s performance and efficiency, which can result in lower output and higher energy usage. Prices of maintenance and repairs are raised as a result of corrosion-related failures, which also cause system downtime and higher replacement part prices. Risks of Contamination: Corrosion products can contaminate product water, lowering its quality and perhaps leading to operational problems farther downstream. …”

The study of membrane capacitive deionization from charge efficiency

“…Desalination has emerged as an effective approach to overcome the water shortage worldwide [1][2][3][4][5][6]. MCDI is a promising desalination technology that may lower the energy demand compared to more established technologies such as reverse osmosis or thermal distillation [7].…”