On 21 November 1988, an agreement was signed at Gaborone (between the Botswana Government, AECI, Anglo American Corporation and De Beers) to build a P736 million soda ash and salt plant at Sua to exploit the natural deposits of the pan.
By April 1991 the plant was in operation.
Concurrent with the construction of the plant, Sowa Town was built at a cost of P100 million and all necessary infrastructure was put in place.
The plant was officially opened on 7 June 1991 by His Excellency, the President of the Republic of Botswana, Sir Ketumile Masire.
During 1995 the company was restructured as Botswana Ash (Pty) Ltd (Botash). The Botswana Government is the major shareholder with 50 %; Anglo American Corporation, AECI and De Beers each hold 14% and the balance of 8 % is held by a bank consortium.
Botash`s head office is at Sua where all company activities - such as production, administration, financing and marketing - are based.
World consumption of soda ash is 50 million tonnes per annum as at end of 2008.
Botash has about 450 employees, majority of whom are citizens.
Botash has an ongoing training / localization programme aimed at reducing reliance on expatriate employees in favor of citizens.
Sowa Town was built to house Botash`s employees and their families and for those providing support services for the Mine and Township.
Sowa Town, situated 20 km from the plant site, was officially opened on 3 August 1990.
The town was built on behalf of the Government by the Botswana Housing Corporation and originally comprised 605 houses. An additional 232 houses were built during a second phase. Botash currently leases 504 of these houses.
Sowa Town has two primary and two secondary schools up to IGSECs level to cater for both English and Setswana pupils.
A free bus service operates for Botash employees between Sowa and the plant.
Sowa Town was commissioned by the Botswana Government to house the Company's employees and their families. Today, it is an active and friendly community, with many essential facilities such as a bank, shops, library, gymnasium and sporting facilities for golf, swimming, tennis, and squash and a modern stadium.
Located in a unique and pristine natural environment in the heart of Africa, Sowa Town is an ideal haven for wildlife and bird enthusiasts, and for those who value this tranquility.
Along with public, state-run schools providing education at primary and secondary levels, the company provides an English medium primary and secondary school for children of employees. The school is well equipped with modern teaching aids and skilled teachers. Learning takes place in a relaxed atmosphere, where the emphasis is on enjoyment. Care is taken to prepare children for the modern world and the school boasts a comprehensive library and a multimedia centre.
Two health facilities namely a Government and a private clinic serve the community and the company's employees, and are geared to treat most emergencies. Specialist cases are treated in Francis town or are flown to Gaborone or Johannesburg . The mine also has an on-site clink to treat employees at the workplace.
Much of the social life centres on the homely Country Club, where more entertainment is available. Sowa Town also boasts an unconventional golf course with sand fairways and novel greens! At weekends, soccer fans flock to the Botash stadium to watch the various football teams such as BOASA, Sunday Times and Sua Flamingoes strut their stuff!
DStv and other international networks are available and provide convenient access to worldwide news and entertainment.
Currently the company is in the process of aligning itself with the ISO14000 international environmental standard.
An Environmental Management System provides order and consistency for organizations to address environmental concerns through the allocation of resources, assignment of responsibilities and ongoing evaluation of practices, procedures and processes.
Botash also has a full-time Environmental Officer.
A few examples of pro-active action taken early in the company`s history include:
The power cables from the spit to the wellfield were buried to prevent interference with the flight path of the flamingos between their feeding and breeding areas.
Effluents are carefully contained and impounded. No contaminants can enter underground water systems supplying neighboring communities.
During construction 15 large marula trees were in the path of development. Rather than cutting down the trees, Botash moved them successfully to Sowa Town where they now provide shade in park areas and in individual gardens.
Under the surface of the dry and saline sands of Sua Pan, a naturally occurring, carbonate-rich resource, brine, is found.
By drilling wells into the underground aquifers below the pan surface, brine is pumped to solar evaporation ponds from where the extraction process begins. (See flow diagram below)
Wellfield: Wells are sunk into the pan surface to extract the brine. The total area of the wellfield is approximately 400 km2, with the centre of the wellfield being 15 km from the plant production site.
Solar evaporation ponds: These shallow ponds operate with a brine depth of about 20 cm, and provide a large surface area for evaporation to occur, using the heat of the sun.
Boiler plant: Two 85 tph, 6 500 kPa pressure, coal-fired boilers produce the process steam requirements and generate up to 20 MW of power to satisfy the electrical requirement of the site. This facility also provides carbon dioxide for the process.
Carbonators: These are a series of large, agitated, glass-flake lined steel tanks. It is in these vessels that the reaction between carbon dioxide and sodium carbonate, to form sodium bicarbonate, takes place.
Calciners: These are large rotary kilns in which the sodium bicarbonate is heated by steam tubes, causing the sodium bicarbonate to decompose into light ash, with the liberation of carbon dioxide and water vapour.
Compactors: Light ash is compressed in the "nip" between two large rollers, to produce solid sheets of ash, which are milled and screened to produce standard dense soda ash.
Bitterns disposal: The spent brine from the ash recovery plant is referred to as bitterns. This liquor is either used in the salt washing process or is pumped into a containment area, specially designed for its disposal with minimal impact to the environment.