One of the main factors of scale in building installations is the presence of calcium carbonate in water, because the solubility of this compound in water is very low and if the conditions are right, it will precipitate quickly. One of the parts that provides these conditions is the surfaces in contact with water in heat exchangers in domestic gas-fired boilers (heat packages).

Localized corrosion caused by the concentration of caustic or alkaline salts, which usually occurs under conditions of high evaporation or heat transfer. Caustic salt or caustic soda is one of the most widely used ionic compounds and is used in various industries including water treatment, cardboard and paper production, oil and refinery industries, aluminum production industries, food industries, alcohol production and glass.

It refers to general or localized corrosion of carbon steels and other metals caused by dissolved salts, gases, organic compounds, or microbiological activity.

Microbial corrosion is a type of corrosion caused by living organisms such as bacteria, algae, or fungi. This type of corrosion is often associated with tubercles or slimy organic materials.

Almost all problems associated with the use of water for cooling purposes can be attributed to one or more impurities such as hardness salts (such as calcium and magnesium, which deposit as scale in pipes and especially on heating surfaces), silica, iron, microbiological species, oil, and dissolved gases. The scaling and corrosion problems caused by the use of naturally hard water in cooling towers during recirculation pose major economic and technical problems, including reduced system efficiency and increased frequency of chemical cleaning.

Corrosion processes are divided into three groups in a more comprehensive classification: corrosion in aqueous solutions or environments, corrosion in molten salts and liquid metals, and corrosion in gases.

Filtration is a method of reducing the amount of suspended particles in a liquid by using porous layers. These particles include mud, plankton, paint, organic matter, and other suspended matter. The first filters used were sand and gravel beds, which were called sand filters.

Corrosion is a natural phenomenon that occurs as a result of the electrochemical reaction of metal with the surrounding environment. In the oil and gas industry, corrosion is one of the major problems that accounts for a huge amount of money annually. Part of these amounts are related to the corrosion of pipes or oil transmission lines. Effective ways to prevent corrosion of oil transmission and storage equipment are divided into two categories: physical and chemical solutions.

The coupon method or corrosion coupons is the simplest method of corrosion monitoring. Coupons are the oldest corrosion monitoring tool. Corrosion coupons are small pieces of metal or alloy of the material of interest that are immersed in the process medium and removed after a specified period of time and their weight or dimension loss is evaluated and examined.

Considering that industrial wastewater causes additional costs in addition to the cost of treating municipal wastewater, the main goal should be to adopt measures that lead to a reduction in additional costs.

Due to the shortage of water in the world, numerous methods have been proposed for separating dissolved salts from brackish water and seawater, including membrane methods including electrodialysis and reverse osmosis.

The antiscalant quality level test or the test to determine the degree of inhibition of antiscalant in dispersing precipitable compounds is designed quantitatively and qualitatively based on international NACE and ASTM standards. This test shows the percentage of inhibition of precipitation of precipitating salts in the presence of the inhibitor.

Gas chromatography-mass spectrometry separates chemical mixtures (gas phase) and identifies components at the molecular level (mass phase). It is one of the most accurate tools for analyzing environmental samples.

Flame photometry is used to determine the concentration of alkaline earth and alkaline elements (in inorganic chemical analysis to determine the concentration of certain metal ions including sodium, potassium, lithium, and calcium) in aqueous solutions.

A spectrophotometer, or visible and ultraviolet spectrometer, sometimes called UV, is a device for measuring the amount of a substance based on the amount of electromagnetic absorption of that substance.

Deaerators are mechanical devices that remove dissolved gases from the boiler feedwater. By reducing the concentration of oxygen and carbon dioxide in the solution, they minimize corrosion and protect the boiler from the effects of corrosive gases.