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Seawater treatment

Sea water treatment in our country, due to access to vast seawater resources in the north and south of Iran, can be one of the ways to produce fresh and healthy water for industries and households. With regard to successive droughts, environmental pollution, reduced groundwater levels, and the shortage of renewable water sources in the country, the use of sea desalinization as a solution to the drought crisis is recommended.

Se water treatment alone can't offset all water resource scarcity because its initial investment price is high. But along with the reform of the consumption culture and water sector infrastructure, sea water treatment can be considered as an option to produce the water needed by high-value industry sectors. The use of distillation and reverse osmosis are among the most important methods of seawater treatment.

 
sea water treatment by reverse osmosis

Sea water treatment is a solution to the drought crisis

Our dear country, Iran has a unique and exceptional position in terms of many mineral resources, oil and gas, fertile land, susceptible and young manpower, and many other geographic and natural facilities. But along with all these possibilities and talents, there is a huge problem and huge constraints on water resources. It can be said that water is the only strategic source that is strictly limited in our country. Therefore, water resources management in various ways, such as the construction of seawater desalination, has become one of the most important concerns of Iran's development today.

Per capita water use varies across countries around the world, depending on geographical location, patterns of consumption and social conditions. Statistical surveys show that in our country, each person consumes 300 liters of water per day, and water consumption of everyone such as agriculture, energy, industry and services is 6000 liters per day. Water consumption in Iran is more than 70 percent of the global consumption pattern. However, Iran's renewable water resources are only 1,400 cubic meters per person per year, and the continuation of the current situation will lead to a water crisis in the near future for our country.

Using seawater treatment, given access to vast seawater resources in the north and south of Iran, can be one of the ways out of the current crisis. In this article, we have tried to explore ways of using a variety of seawater desalinators and seawater treatment methods for the supply of fresh water needed by the country.

Allocation of funds to seawater treatment projects

About 85% of the country's total water resources are consumed in the agricultural sector, with a share of household use of 8% and industry of 7%. Nowadays, due to the old methods of cultivation and irrigation, the efficiency of the agricultural sector is very low and most of the water use in this area is unnecessary and can be reduced by correcting irrigation methods.

In the macroeconomic management of the economy, strategic prioritization regarding the allocation of funding to construction and infrastructure projects is considered as one of the most important topics. Considering all of the above issues regarding the distribution of God's resources and funds in the country, there should be a basic look at the role of water in the development of the country's infrastructure. We can safely say that none of the mineral, oil and manufacturing industries in our country can continue to operate without water. However, despite the decline in underground wells, the loss of renewable sources of water, the increased pollution of existing resources, this day is tightening and looking at the desalinating seawater.

Therefore, the issue of safe water supply and use of domestic, industrial and agricultural sectors is one of the main concerns of the Iranian economy. The issue of the environment and the provision of safe water has become a crisis, but it is by no means an unbreakable problem. Although Iran is one of the poorest countries in terms of seasonal rainfall and renewable resources, it has access to vast sea water resources from the south and north. Using seawater treatment is one of the ways to cope with drought and water scarcity in Iran. As in the Persian Gulf countries, that they have overcome the problem of dehydration by using a variety of seawater treatment.

Seawater treatment is one of the ways to cope with water scarcity. There is no doubt that other methods, besides seawater treatment, can be considered in solving the dehydration problem in Iran, including improving irrigation methods, improving water supply networks, improving consumption culture, promoting energy saving, fertilizing Clouds, watersheds, and renewable sources of water.

The important thing is that the industry sector can be placed in the priority of using seawater treatment projects in terms of high production value added. Because the initial investment in the establishment of seawater treatment and then the transfer of refined water is very high, there is no such huge investment in the agricultural sector and even in the current situation. In particular, the volume of water consumed in the agricultural sector is very high and the supply of this water by seawater desalination is practically wasteful of funds. However, industrial sectors due to high working capital, less water consumption than the agricultural sector and high added value of production, have priority to the use of seawater desalination. In the second stage, household sections can be used to sweetening the seawater by desalination machine.

 
seawater desalination

The role of seawater desalinating in water resources management

The major mines of Iran are mainly located on the central plateau and in the dry and dehydrated cities like Kerman and Yazd. The largest industries in our country, such as steel and iron, are in dehydrated cities such as Isfahan. In many Iranian cities such as Zanjan and Qazvin, small and medium-sized industries are active. In the metropolitan area like Tehran, there are many manufacturing and automotive industries. In the south, there is a wide range of oil and gas and petrochemical industries, which are also equipped with a variety of seawater desalinators. But the reality is that apart from the northern parts of our country, most regions face a water crisis.

Our dear country, Iran is in a warm and dry area. Iran is the poorest country in terms of per capita water resources in the continent of Asia. Therefore, in year 1400, Iran is expected to face severe water shortages. On the other hand, many water resources that have been used for many years have been lost due to successive droughts. The increase of industrial and sanitary wastewater pollution has also caused the loss of ecosystems and the cycle of renewable water production. These contaminants in three parts of the country's water, soil and air have caused a depression crisis and loss of resources.

The fact is that groundwater levels have fallen sharply in all regions of Iran and more than 70% of groundwater resources are in use, which means the alarm has come to a halt. The nature of Iran can not produce the water consumed by the country. Now, we need to find suitable alternatives that will overcome the shortage of water in the short term and, in the long run, save water from Iran's own ecosystem by saving water.

One of the important points in water resources management is the culture of water saving in all consumer sectors such as agriculture, industry and home. But the sad truth is that many water losses in the country are due to the lack of proper infrastructure alongside the wrong culture. For example, in most of Iran's water supply networks, we see 20% of water leakage due to the burnout of the facility. In the agricultural sector, we are also witnessing the cultivation of products whose actual water prices are higher than agricultural prices. In the industrial sector, we also see the wear and tear of equipment and machinery that heavily consumes water.

In such circumstances, if we are to be realistic, we can't, in the short term, revise all of the economic infrastructure of water use, but, along with the gradual improvement of manufacturing infrastructure, we need to provide new and cheap water resources such as refined water of seawater desalinating The consumer will put us in the position of revising the water consumption infrastructure. The use of seawater desalination and a variety of industrial sweeteners can be a short-term solution to managing water resources.

Experience in the use of seawater treatment

Persian Gulf countries, like Iran, face dehydration by it all means. In these countries, the use of sea water resources and all kinds of desalinating seawater has been selected as a sustainable solution to the problem of desalinization of seawater and the production of water from the industrial, agricultural and household sectors. For example, Saudi Arabia's desalinating water in Ra'as al-Khair produces only one million cubic meters of fresh water a day. By investing in large-scale offshore water utilities, these countries have reduced the price of seawater treatment to produce one liter of water. Because the major part of investment in sewage treatment is the initial investment cost for the construction of facilities and structures.

Methods of water purification by seawater desalination

Sea water contains 3 to 4 percent of the impurity, called salinity or, in the scientific sense, the total dissolved soluble (TDS). This is while water wells in Iran have about 0.2 to 0.5 percent impurities and salts. On the other hand, tiny creatures are found in sea water. There are some toxic compounds, such as Boron (B), in seawater that are harmful to human health. All of this shows the difficulty of sea treatment by seawater desalination. But how to make the seawater sweet?

Seawater desalination is being equipped and manufactured in various ways, the most important of which is the MED distillation and reverse osmosis RO. The MED method, which is based on the distillation method, produces very pure water, which is mainly industrial. The use of this method is very common for large volumes of water and because of the change in the physical state of water, there is a high energy consumption. The reverse osmosis method in seawater treatment is based on the use of semi-permeable membranes and can be used in seawater desalination plants in various dimensions. The reverse osmosis method is very common due to lower initial investment and ease of operation compared to MED in seawater desalination.

 
How Sea water treatment work?

The price of seawater treatment

There is no doubt that seawater treatment by seawater is costly and requires a lot of initial investment due to the high salinity of the seawater treatment. In any case, although the cost of seawater-sweetener is high, it can be used by some methods, such as solar desalination, or seawater desalination in the shelters, to reduce initial investment costs for freshwater production in small sizes.

The use of reverse osmosis as a desalinator is one of the most optimal methods of water treatment because the initial investment price is reasonable and will result in low operating costs and energy consumption.
Ultimately, although the desalinator can be a new source of water for the country, it can not solve all the depleted water due to the price of finished water alone. Therefore, the use of desalinating water for important sectors of production and, in addition, the reform of the consumption culture and water infrastructure of the country can be a long-term solution to the Iranian water shortage crisis.