Origin of potassium nitrate
In agriculture, potassium nitrate is used as a soluble fertilizer and is a source of nitric nitrogen and potassium, which is virtually free of chloride. Potassium nitrate is an ideal source of N and K for optimal plant growth and contributes to the health and performance of crops.
Potassium nitrate is obtained through a process that mixes sodium nitrate, derived from Caliche and potassium chloride, obtained from the brines from Salar de Atacama, in northern Chile. This process uses solutions rich in sodium nitrate to which potassium chloride is added, producing the reaction to obtain potassium nitrate.
To obtain sodium nitrate, the primary extraction of the mine is done by blasting, followed by mechanical extraction to remove tonnes of earth and rock. At the Maria Elena, Nueva Victoria and Pampa Blanca facilities, the ore is leached in stocks, obtaining solutions intended primarily to produce iodine. Next, the solutions are transported to solar evaporation ponds where the salts crystallize and contain high concentrations of nitrate. Finally, they are transported by truck to the Coya Sur facilities, where they are used in the production process of potassium nitrate.
Brines, present in concentrated form in the cracks beneath the surface of the Atacama Salt Flat, are extracted from pumping wells that are strategically situated in various parts of the Atacama Salt Flat. After being extracted, the brine is pumped to huge evaporation ponds. There, it remains under the desert sun, in order to increase its concentration. The evaporation rate in this desert location is very high, at around 10 liters per square meter per day. The concentration is constantly monitored in each evaporation pond. Over time, the remaining brine is pumped out, and the salt is harvested.
After a series of evaporations, part of the pumped brine is recovered as a concentrated solution of lithium chloride, a by-product of potassium chloride. Another part of the already concentrated brine is re-injected into underground salt deposits of the Atacama Salt Flat. The salts deposited in the evaporation ponds are appropriately harvested and transported.
Finally, after crushing, froth flotation, drying and compacting processes, potassium chloride, potassium sulphate and boric acid are obtained.
Specialty Plant Nutrition
Specialty Plant Nutrition is SQM's business line that provides specialized nutritional solutions for fertigation, soil and foliar applications, which, together with the experience and knowledge of our technical agronomic team, provide the necessary macro and microelements to increase the profitability of our clients' agricultural businesses.
SQM's Specialty Plant Nutrition Solutions, Ultrasol®, Qrop® and Speedfol® are powered by “Element Q”, along with SQM's unique warranty seal, whose impact on your field will boost both the result of your crops and your business.
SQM is a company with worldwide presence in industries essential for human development, through five principal business lines: specialty plant nutrition, lithium and derivatives, iodine and derivatives, industrial chemicals and potassium.
Throughout our 50 years of innovation and technological development, we have established ourselves as world leaders in the lithium, potassium nitrate, iodine and thermo-solar salts markets.
We have surpassed the 2 billion US dollar mark in sales, managed by the 20 commercial offices, distributed among five continents, giving us a presence in 115 countries.
To achieve world leadership, we have invested heavily to increase our production capacity, open new facilities, train our people; conduct research; improve technology and take actions to understand the needs of our customers.
With operations in Salar de Atacama, Coya Sur, María Elena, Pedro de Valdivia, Tocopilla, Salar del Carmen and Nueva Victoria, we are the heirs of the saltpeter industry; and through a base of innovation and meticulous engineering work, we have reinvented it.
Today, not only do we offer quality products and services, but we work together with our clients around the world to achieve the success of their businesses, making SQM a strategic ally.
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Caliche ore, the history of Chilean nitrate
Caliche is a mineral that contains high concentrations of nitrate and iodine, and, to a lesser Extent, potassium. Caliche is encountered in layers or veins which are from 20 cm up to 5 meters thick, covered by a shallow, sterile surface layer that can be from half a meter up to 1.5 meters thick. Uses for caliche have been known for a long time by the native peoples, and during the Spanish conquest in the 17th century it was used as an agricultural fertilizer. Caliche stems from the Quechua word “cachi”, meaning salt.
In the early 19th century, the first form of caliche exploitation started in the so-called “paradas,” settlements of people in areas where the mineral was found. Individually, or in groups armed with a spade, these men extracted the ore, a process which, in the course of time, and thanks to the industry boom since the first shipment to Europe in 1830, grew to become the large, industrialized saltpeter works (more than plants 300 between 1880 and 1996).
The only remaining active plant is María Elena, named after Mary Ellen Condon, the wife of the first Plant Manager, Elias Cappelen. Built on land bought from the Chilean government in 1924, the plant was opened in 1926, equipped with the saltpeter extraction system patented by the Guggenheim Brothers, which replaced the Shanks system. Together with the former Pedro de Valdivia Saltpeter Works, built in 1931, they were the largest saltpeter works (also called nitrate towns), with a combined production capacity exceeding one million tonnes per year.
Today, in the new global economy, there is a new focus on the exploitation of caliche to extract iodine and nitrates, which along with the brines of the Atacama Salt Flat, are vital resources for national and global development. For SQM, the natural heir of this great industry, natural resources are essential to provide the best products and services to its customers. Consequently, SQM is continuously implementing new processes, the most advanced technologies and the most innovative solutions to maximize the available resources, with sustainable and efficient operations.
At SQM, we’re celebrating 50 years. Through effort, consistency and dedication, we’ve worked to achieve excellence. Our goal is to deliver our customers the best of us, our best harvest. During this 50-year journey, we have introduced unique products that help generate life, thanks to excellent plant nutrition. We’re committed to a strong future of new developments that cross borders worldwide, and are constantly working on innovative technologies for sustainable plant growth.
In 1930, the Chilean government created the company “Compañía de Salitre de Chile”, COSACH, of which, the Chilean state owned 50% and private companies that still used the Shanks system (a total of 37 companies) owned the remaining 50%. Due to its poor results, the company was liquidated in 1933 and replaced by the “Saltpeter and Iodine Sales Corporation of Chile” (COVENSA), and at which time companies using the Guggenheim method were incorporated: the Anglo-Chilean Saltpeter Company and the Lautaro Nitrate Company, which meant important changes in the concession and nitrate exploitation. In 1968, the Anglo-Lautaro became part of the “Sociedad Química y Minera de Chile”, currently known as SQM®
The Guggenheim family acquires land in El Toco area and opens the Maria Elena nitrate office
A nitrate crystallizing plant is built in Coya Sur in order to take advantage of nitrate precipitation from solar evaporation ponds
SQM is created through the merger of Corporación de Ventas de Salitre y Yodo, Compañía Salitrera Anglo Lautaro, Compañía Victoria and the Chilean government
SQM’s privatization process begins, concluding in 1988, and private pension funds acquire an ownership stake
The potassium nitrate facility at Coya Sur begins production using a completely new process designed by SQM
TECHNICAL POTASSIUM NITRATE
Operations begin at a technical grade potassium nitrate facility. SQM completes its first share issuance on international markets through its ADR program
SQM expands its potassium chloride production in the Salar de Atacama and builds a new potassium nitrate plant at Coya Sur
PRILLING AND GRANULATION
Production begins at the new nitrate prilling and granulation plant at Coya Sur
SQM signs new joint ventures with Coromandel (India), Qingdao Star (China) and Roullier (France)
Production commences in a new potassium nitrate plant in Coya Sur, increasing production by 300,000 tons per year
SQM expands production capacity of potassium products in its facilities in the Salar de Atacama, achieving production of approximately 2 million tons per year
SQM opens new logistics terminal in Terneuzen, the Netherlands
SQM increases the total production capacity of potassium nitrate, reaching 1.5 million tons per year. Celebration of the 50th anniversary