In some areas where fresh water is scare, growers are desalinizing underground water to irrigate their crops. In one hand it looks good to overcome the shortage of water to continue growing the crops. On the other hand, beside the fresh water produced, the concentrated saline solution coming out of the reverse osmosis station is pumped back to the underground.
So, do not you think that this approach is more harmful to the environment and increases the salinity of the underground aquifer?
Well,
The desalination process will not be environmentally friendly. It involves the process of generating a salt waste that needs to be transported or removed, and on the other hand it is not economically feasible.
Regards
For sure desalination is not environmentally friendly, both from an environmental but also from an economic point of view. I think that a more sustainable approach could be wastewater reuse for irrigation; wastewater is continuously available 365 days per year and the treatment process can be tuned to leave some nutrients in the treated water, reducing the need for chemical fertilizers.
Regards
Desalinized water is increasingly considered a source of water for agriculture as well. With 69% of the global water supply going to irrigation, present freshwater resources may soon be insufficient to meet the growing demand for food. A recent report concludes that, although the costs of desalination remain prohibitively expensive for full use by irrigated agriculture, for high value cash crops like greenhouse vegetables and flowers, its use may be economically feasible
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I believe that the desalination of water is not necessarily unfriendly to the environment. That criterion can generate an erroneous assessment regarding the alternative of desalination of seawater for the production of drinking water.
The fact can not be denied that if there is no suitable treatment and design in concentrate discharges we can generate unwanted environmental effects. A controlled discharge of the brine obtained during the desalination is needed.
Due of the importance of the subject, I think it is a good point to discuss aspects in favor and against
For this process, the cost and power consumption is high. Reverse osmosis is usually used in seawater desalination and waste separation in some special cases. For underground water, if it's not fit for irrigation, I don't think the tech would be economically or environmentally suitable for the area.
it is not only a matter of environmental concern. usually it is evaluated as a situation in case by case. as you mentioned, if the area does not have suitable water for drinking or irrigation, then it is a matter of survival and you have to look to the proprieties imposed in your situation. Economically, of course using desalinized water for irrigation is a not feasible, but in case of the country can not import or the cost of import is higher than the situation is different. countries that are using desalinized water in agriculture usually make the most of its use, for example using it in closed system of soilless culture or aquaponic then release the drainage to be used in irrigating open field crops.
In conclusion, it is a wider picture and a balance of advantages and disadvantages controlled by priorities.
Nice points of view. Thank you all for your valuable opinions. .
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