Brine is water containing concentrated salt. In other words, it’s a highly concentrated alkaline solution. Natural brine occurs naturally underground as seawater or in salty lakes. It is the commercial source of common salt (sodium chloride) plus other salts like sulfates of potassium and magnesium, as well as chlorides.
Although brine contains many materials, the common salt is the main component in the compound that gives seawater its salty taste. On average, the seawater is made up of 3% salt. Enclosed water bodies like the Mediterranean Sea and the Red Sea contain a higher percentage of common salt than other open oceans at the same latitude.
Uses of Brine
Brine services are rampant in both homes, industries, and commercial places. The natural brine used commercially originates from the Dead Sea, United Kingdom, Austria, Germany, France, the United States, and India.
Brine is used in hotels and homes to marinate meat, especially corned beef, to make it soft and add flavor. It can also be applied to vegetables, fruits, and cheese in a process known as picking. The salty nature of brine is also used in homes to preserve food over a short period.
In Refrigeration and Cooling Systems
Brine has very low freezing temperatures, going as low as -21.1 degrees Celsius (-0.5 degrees Fahrenheit), and low vapor pressure. As a result, it’s commonly used during refrigeration as a heat transfer media as well as vapor absorption agents.
Production of Chlorine
Basic chlorine can be produced by electrolysis of brine (NaCl solution). The process can also produce hydrogen gas (H2), and sodium chloride (NaOH).
Water Softening and Purification
Brine is a supplementary agent in water softening and purification systems involving ion exchange technology. Examples include the home dishwasher, where sodium chloride is used as dishwasher salt. Although brine is not directly involved, it is used to regenerate ion exchange resin on a cyclical basis.
During low temperatures, the brine solution can be used to de-ice or reduce freezing temperatures on roads.
Brine Management and Disposal
Apart from the natural brine originating from the Dead Sea, industrial activities like fracturing, desalination, or power plant towers also release big volumes of brine water. This solution can be hazardous to the environment because, alongside the diluted salts, it can also contain residues of pretreatment and cleaning chemicals, by-products, and heavy metals due to corrosion. Therefore, it’s essential to manage them well and dispose of them properly to avoid pollution.
The brine (wastewater) can be disposed of in several ways. Deciding on the right method depends on the availability of disposal methods, applicable discharge regulations, and economic feasibility to treat the brine. Some of the disposal methods include:
- Returning wastewater to the ocean
- Diluting with other streams of water to limit environmental impact
- Brine is heavier than seawater and may accumulate at the bottom of the ocean. Installing diffusers in sewage will help in diffusing the brine completely
- Drying in evaporation ponds
- Injecting to deep wells
- Storing and reusing brine for irrigation, de-icing or dust control
Handling brine water, especially the wastewater from factories, can be delicate and requires care. It’s therefore advisable to seek professional advice concerning all brine services so that at the end of the day, the brine is disposed of, and the environment is not affected.