Grow Tip: Don’t Filter Your Water – The True Usage of Reverse Osmosis Systems
What is Reverse Osmosis, Anyway?
Reverse osmosis simply referred to as RO, is a process of water purification that utilizes technology almost similar to ultra-filtration. A semi-permeable membrane is used to remove larger molecules from the normal water in order to produce pure water (solvent), which can be used for drinking, domestic purposes, agriculture, and industrial purposes. However, during reverse osmosis pressure is applied against the osmotic pressure, a process that is stimulated by a thermodynamic parameter of chemical potential.
Reverse osmosis gets rid of many particles (molecules and ions) from contaminated water. These particles include microorganisms and bacteria, and therefore resulting in clean and safe water for drinking. Many portable water packages are produced through RO, as well as in the production of industrial pure water that is used in chemical applications.
During the RO process, the solute is kept on the pressurized side of the semi-permeable membrane while the solvent is forced to pass through it. The membrane is highly ‘selective’ as it allows only smaller particles or molecules of water to pass freely while the larger molecules are retained.
For the water to pass through the membrane, a pressure is applied to the concentrated solution. A pump can be used to provide the pressure so that water and other lighter molecules (usually less than 200 grams per mole) are allowed to pass through the tiny pores of the membrane. The modern RO system is normally installed using a cross-flow so that the membrane can clean itself continuously, meaning that the ‘rejected’ particles are swept away from the semi-permeable membrane.
Is RO Water Ideal for Your Garden?
One of the main concerns about the use of RO water in gardens is the absence of some essential minerals. However, there is a way to add minerals back into RO water so that you can use it for your plants. But, our case here is whether or not RO is good for plants. This article will explore briefly that area so that you can have a clear understanding of this issue.
For plant growers, it is important to balance the intake of nutrients by your plants so that they can thrive well. Traditional water (contaminated water) contains a high level of impurities, which makes the nutrient-balance difficult to achieve. With RO water, you can provide the plants with pure water free from contaminants at their initial growth stage. This helps you calculate the mineral balance accurately, as well as eliminating the possible reactions if you use chemically-manufactured fertilizers.
When it comes to disadvantages of RO water, one of them is that a large amount of water that goes to waste. If you want to use RO water for a large garden, perhaps you are going to spend more money on water bills. On average, 3 gallons of tap water are used to produce one single gallon of pure water. So, there is a lot of water that will go to waste if you switch from normal to RO water. Another disadvantage is the absence of salts that are wanted by the plants to grow well. Some growers usually add fertilizer salts in order to restore the suitable salt content. The recommended amount of salt is one teaspoon per gallon of reverse osmosis water.
Even though many people claim that RO water is not good for plants, I would say it is. The disadvantages can be managed so that you can only enjoy the advantages. As mentioned earlier, there are ways to add essential minerals in your RO water in order to make it nutritious for your plants.
The Actual Applications of Reverse Osmosis System
Apart from purifying water for drinking, reverse osmosis systems are largely applied in commercial and industrial settings where a large amount of pure water is required. The RO system should operate at pressures between 150 psig and 1,000 psig depending on the semi-permeable membrane used and level of water quality to be treated. Some applications may require the use of a series of membranes in order to produce a greater purity of water.
The wastewater can also be forced through other advanced membranes to maximize RO water generation without wasting a huge amount of water. However, the wastewater may be flushed if some bad odor is detected. The most common applications of reverse osmosis include desalination of brackish water, desalination of seawater, generation of ultrapure water, and treatment of wastewater.