The three main purposes of water consumption are sanitation, cooling and warming systems, and electricity production. In Iran the majority of water is used for cooling and generating electricity accounting for 60% of the total water consumption. Additionally 30% of the water is utilized for sanitation purposes and in various industries. The industries that require a significant amount of water consumption include food processing, water bottling, paper production, coal mining, refining, chemical manufacturing, basic metals production, and non-metallic minerals production.
According to official reports the food processing sector consumed the most water in Iran in 2010 accounting for 18% of the total water consumption by the industry. In the following we will examine the water consumption status of other significant industries that consume high amounts of water.
1. Iron and steel and related sectors to them
Iran is currently experiencing water scarcity yet it has a significant steel production industry located in arid regions such as Isfahan, Yazd, and Kerman provinces. Manufacturing steel requires a large amount of water to cool equipment, facilitate the manufacturing process, polish surfaces, transport steam, oil, and basic solutions, and control air pollution.
According to the American Iron and Steel Institute (AISI) it is estimated that 8.19 cubic meters of water are required to manufacture each ton of steel. For instance in Iran at Mobarakeh Steel Company where the production capacity of steel is 10 million tons a staggering 40 million cubic meters of water is utilized. In addition at Esfahan Steel Company 18 million cubic meters of water are required to produce 3.6 million tons of steel.
2. Water packaging:
In Iran there are 172 companies operating in the water packaging industry. These companies are bottling water from 1 to 5.1 billion liters of water. Out of these companies 77 package drinking water while the remaining 95 package mineral water. To meet their production needs 122 water boreholes are authorized for extraction.
The annual bottled water consumption varies greatly among different countries. For instance in Iran people consume between 15 to 20 liters of bottled water annually, while in Turkey, Saudi Arabia, Qatar, Lebanon, Spain, Germany, and Thailand, the annual consumption rates are 130, 100, 103, 24, 115, 140, and 170 liters, respectively.
3. Food and dairy production
Currently there are 2,759 active food sectors in Iran which consume a total of 403 million cubic meters of water. This industry requires water for various purposes including washing to remove dirt and impurities displacement of materials during different processes wetting wheat before milling, primary warming, blanching, tampering, heat transport, boiler consumption, and so on.
Dairy product companies in Iran consume approximately 40 million cubic meters of water which accounts for 2% of the total water consumption across all industries. The water is mainly used for production, cooling boilers and chillers, washing equipment, machinery, company salons, and general usage.
4. Textile and leather industries
In the textile industry the coloring and washing processes tend to consume more water than printing processes. Other activities that contribute to water consumption in this industry include bleaching, cooking, and whitening of cotton, as well as washing clothes. On average the textile industry uses about 100 to 200 liters of water for every kilogram of product.
Similarly in the leather manufacturing process, tanning, soaking, and washing of hides require significant amounts of water.
5. Paper industry
It is important to note that the paper manufacturing industry is responsible for a high amount of water consumption. For every ton of paper produced approximately 10 to 15 cubic meters of water are required. Water is used in various stages of the paper manufacturing process including preparing raw materials, washing pulp, and cleaning machinery. Additionally water is necessary for cooling various processes, transporting materials, cleaning equipment, operating machinery, producing steam in boilers, and for general purposes such as staff consumption, cleaning non-sensitive surfaces, firefighting, and irrigation.
6. Automobile manufacturing:
The automobile manufacturing process requires the use of water much like other industries. Roughly 800,000 liters of water are required to manufacture each car. This water is utilized for cooling down and lubricating the engine machining process adjusting moisture levels and washing the car during the painting process.
7. Electrical and chemical
Many industries such as those involved in electrical work battery manufacturing, chemical material production, and plastic production, require a significant amount of water for cooling down industrial processes, washing, and other operations. Research conducted on 18 industrial factories in Tehran has revealed that among these industries plastic production requires the highest amount of water while the electrical industry consumes the least amount of water.
8. Pharmaceuticals, cosmetics, and hygiene
In these industries distilled and deionized water are primarily used. Deionized water is obtained during drinking water purification processes that are supplied by municipal water resources or water boreholes. It is commonly used as a solvent to dissolve raw materials in the production of cosmetic and hygienic products. Additionally it is used as a primary material in the manufacturing of medicines.