Evaporation ponds are artificial ponds with very large surface areas that are designed to efficiently evaporate water by sunlight and expose water to the ambient temperatures. [1] Evaporation ponds are inexpensive to design making it ideal for multiple purposes such as wastewater treatment processes, storage, and extraction of minerals. [2] [3] Evaporation ponds differ in purpose and may result in a wide range of environmental and health effects. [2]
Salt evaporation ponds produce salt from seawater. [4] Evaporation ponds are used to extract lithium from underground brine solution. The extracted Lithium is then used to make ion batteries. [5] [3] Mines use them to separate ore from water. The ore can be sold for use in different industries. [3] Potash evaporation ponds are used to extract potassium from the mineral rich solution. The potassium extracted is used for products like fertilizer. [6]
Evaporation ponds are also used to dispose of brine from desalination plants. [4] Evaporation ponds at contaminated sites remove the water from hazardous waste, which reduces its weight and volume and allows it to be more easily transported and stored. [3] [4] Evaporation ponds are used to prevent run off agricultural wastewater contaminants like pesticides, fertilizers and salts from entering bodies of water they would normally flow into. [2]
Location of the evaporation pond should be considered for optimal results. Evaporation will be higher in places with high amounts of solar radiation, high temperatures, and low wind levels. Since evaporation ponds operate best with greater surface area of evaporation, large amount of land is required, so low quality, low cost land is better [2] A shallow pond covering greater surface area will result in faster rates of evaporation. [2] .
An evaporation pond has shallow depths and, to prevent contamination of the environment from its content, a range of pond liners are used, categorized as geomembrane, constructed bentonite clay, or natural clay. [7] Each pond liner is prone to leakage and requires regular maintenance. [2] The contents of the evaporation pond depend on the use, the evaporation pond will contain water and the desired contents hoping to be extracted. The desired contents range from waste to minerals, and the remaining contents are either stored or extracted. [2]
Evaporation ponds, when not maintained, may leak contaminated contents into the environment which directly effect human and animal health. [2] The contents within the evaporation pond can be found to contaminate surrounding soil and surrounding water sources. Contaminated water can contain sources of chemicals and hard metals like selenium which in accumulation can be toxic when ingested by humans or animals. [2] [8] Employees working directly with the evaporation ponds may experience acute health conditions like dry skin and irritation from close contact of contents within the pond. [2]
Evaporation ponds pose a threat to environmental sustainability because resources like water, land, and minerals are rapidly used at large scales. These resources are limited in nature. An increasing demand for extracted products and treated wastewater will result in evaporation ponds expanding and related issues worsening until the depletion of these resources. [2] Evaporation ponds are found to increase green house gas emissions and therefore contribute to environmental issues like warming of the planet and ocean acidification. As the pond evaporates, it carries with it volatile pollutants into the air. [2]
Advancing technology has made evaporation pond design and implementation more effective. With new resources such as fabric evaporations for salt-tolerant plants, the ponds' costs and environmental impacts can be mediated. [9]
Lithium carbonate is an inorganic compound, the lithium salt of carbonic acid with the formula Li
2CO
3. This white salt is widely used in processing metal oxides. It is on the World Health Organization's List of Essential Medicines for its efficacy in the treatment of mood disorders such as bipolar disorder.
Brine is water with a high-concentration solution of salt. In diverse contexts, brine may refer to the salt solutions ranging from about 3.5% up to about 26%. Brine forms naturally due to evaporation of ground saline water but it is also generated in the mining of sodium chloride. Brine is used for food processing and cooking, for de-icing of roads and other structures, and in a number of technological processes. It is also a by-product of many industrial processes, such as desalination, so it requires wastewater treatment for proper disposal or further utilization.
Desalination is a process that removes mineral components from saline water. More generally, desalination is the removal of salts and minerals from a substance. One example is soil desalination. This is important for agriculture. It is possible to desalinate saltwater, especially sea water, to produce water for human consumption or irrigation. The by-product of the desalination process is brine. Many seagoing ships and submarines use desalination. Modern interest in desalination mostly focuses on cost-effective provision of fresh water for human use. Along with recycled wastewater, it is one of the few water resources independent of rainfall.
Geothermal desalination refers to the process of using geothermal energy to power the process of converting salt water to fresh water. The process is considered economically efficient, and while overall environmental impact is uncertain, it has potential to be more environmentally friendly compared to conventional desalination options. Geothermal desalination plants have already been successful in various regions, and there is potential for further development to allow the process to be used in an increased number of water scarce regions.
Seawater, or sea water, is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of about 3.5%. This means that every kilogram of seawater has approximately 35 grams (1.2 oz) of dissolved salts. The average density at the surface is 1.025 kg/L. Seawater is denser than both fresh water and pure water because the dissolved salts increase the mass by a larger proportion than the volume. The freezing point of seawater decreases as salt concentration increases. At typical salinity, it freezes at about −2 °C (28 °F). The coldest seawater still in the liquid state ever recorded was found in 2010, in a stream under an Antarctic glacier: the measured temperature was −2.6 °C (27.3 °F).
Natural salt pans or salt flats are flat expanses of ground covered with salt and other minerals, usually shining white under the sun. They are found in deserts and are natural formations.
A salt evaporation pond is a shallow artificial salt pan designed to extract salts from sea water or other brines. The salt pans are shallow and expansive, allowing sunlight to penetrate and reach the seawater. Natural salt pans are formed through geologic processes, where evaporating water leaves behind salt deposits. Some salt evaporation ponds are only slightly modified from their natural version, such as the ponds on Great Inagua in the Bahamas, or the ponds in Jasiira, a few kilometres south of Mogadishu, where seawater is trapped and left to evaporate in the sun.
Industrial wastewater treatment describes the processes used for treating wastewater that is produced by industries as an undesirable by-product. After treatment, the treated industrial wastewater may be reused or released to a sanitary sewer or to a surface water in the environment. Some industrial facilities generate wastewater that can be treated in sewage treatment plants. Most industrial processes, such as petroleum refineries, chemical and petrochemical plants have their own specialized facilities to treat their wastewaters so that the pollutant concentrations in the treated wastewater comply with the regulations regarding disposal of wastewaters into sewers or into rivers, lakes or oceans. This applies to industries that generate wastewater with high concentrations of organic matter, toxic pollutants or nutrients such as ammonia. Some industries install a pre-treatment system to remove some pollutants, and then discharge the partially treated wastewater to the municipal sewer system.
Solar desalination is a desalination technique powered by solar energy. The two common methods are direct (thermal) and indirect (photovoltaic).
Osmotic power, salinity gradient power or blue energy is the energy available from the difference in the salt concentration between seawater and river water. Two practical methods for this are reverse electrodialysis (RED) and pressure retarded osmosis (PRO). Both processes rely on osmosis with membranes. The key waste product is brackish water. This byproduct is the result of natural forces that are being harnessed: the flow of fresh water into seas that are made up of salt water.
Menachem Elimelech is the Sterling Professor of Chemical and Environmental Engineering at Yale University. Elimelech is the only professor from an engineering department at Yale to be awarded the Sterling professorship since its establishment in 1920. Elimelech moved from the University of California, Los Angeles (UCLA) to Yale University in 1998 and founded Yale's Environmental Engineering program.
Bittern, or nigari, is the salt solution formed when halite precipitates from seawater or brines. Bitterns contain magnesium, calcium, and potassium ions as well as chloride, sulfate, iodide, and other ions.
Water resources are natural resources of water that are potentially useful for humans, for example as a source of drinking water supply or irrigation water. These resources can be either freshwater from natural sources, or water produced artificially from other sources, such as from reclaimed water (wastewater) or desalinated water (seawater). 97% of the water on Earth is salt water and only three percent is fresh water; slightly over two-thirds of this is frozen in glaciers and polar ice caps. The remaining unfrozen freshwater is found mainly as groundwater, with only a small fraction present above ground or in the air. Natural sources of fresh water include surface water, under river flow, groundwater and frozen water. People use water resources for agricultural, industrial and household activities.
Reverse osmosis (RO) is a water purification process that uses a semi-permeable membrane to separate water molecules from other substances. RO applies pressure to overcome osmotic pressure that favors even distributions. RO can remove dissolved or suspended chemical species as well as biological substances, and is used in industrial processes and the production of potable water. RO retains the solute on the pressurized side of the membrane and the purified solvent passes to the other side. The relative sizes of the various molecules determines what passes through. "Selective" membranes reject large molecules, while accepting smaller molecules.
Pressure retarded osmosis (PRO) is a technique to separate a solvent from a solution that is more concentrated and also pressurized. A semipermeable membrane allows the solvent to pass to the concentrated solution side by osmosis. The technique can be used to generate power from the salinity gradient energy resulting from the difference in the salt concentration between sea and river water.
Zero Liquid Discharge(ZLD) is a classification of water treatment processes intended to reduce wastewater efficiently and produce clean water that is suitable for reuse (e.g., irrigation). ZLD systems employ wastewater treatment technologies and desalination to purify and recycle virtually all wastewater received.
Brine mining is the extraction of useful materials which are naturally dissolved in brine. The brine may be seawater, other surface water, groundwater, or hyper-saline solutions from several industries. It differs from solution mining or in-situ leaching in that those methods inject water or chemicals to dissolve materials which are in a solid state; in brine mining, the materials are already dissolved.
Petrolithium is lithium derived from petroleum brine, the mineral-rich salt solution that is brought to the surface during oil and gas production and exploration.
The Lithium Triangle is a region of the Andes that is rich in lithium reserves, encompassed by the borders of Argentina, Bolivia, and Chile. The lithium in the triangle is concentrated in various salt pans that exist along the Atacama Desert and neighboring arid areas. The largest areas three main salt pans that define its vertices are the Salar de Uyuni in Bolivia, Salar de Atacama in Chile, and Salar del Hombre Muerto in Argentina. Of these, the core of Salar de Atacama in Chile has the highest concentration of lithium among all world's brine sources.
Lithium batteries are batteries that use lithium as an anode. This type of battery is also referred to as a lithium-ion battery and is most commonly used for electric vehicles and electronics. The first type of lithium battery was created by the British chemist M. Stanley Whittingham in the early 1970s and used titanium and lithium as the electrodes. Applications for this battery were limited by the high prices of titanium and the unpleasant scent that the reaction produced. Today's lithium-ion battery, modeled after the Whittingham attempt by Akira Yoshino, was first developed in 1985.
