Water production History
Aruba begins desalinating seawater
The desalination history of Aruba started more than a hundred years ago with the production of process water around 1903 at the Gold Mining Company (1899-1916).
Even at that early stage, it was obvious that the groundwater and rainwater reserves were insufficient for the physiochemical gold extraction process. The decision was made to desalinate seawater from the nearby Spanish lagoon.
Landswatervoorziening is founded
From 1932 to 1983 drinking water and industrial water were produced using the Multi Effect thermal desalination technology.
Since the first desalination activities in 1932 till mid-2007, WEB Aruba produced distilled water, adjusted to approximately:
- 12 mg/L total hardness
- 12 mg/L alkalinity, and
- pH 8.8-9.3
This was achieved by cascading it down over a bed of natural crushed coral. The coral served as an economical source of calcium carbonate (lime stone) which dissolves at a controlled rate, raising the pH above neutral and imparting some calcium (hardness) and carbonate/bicarbonate buffering (alkalinity) to the water before it enters the distribution piping
Introduction of combined power and water production
Five MED evaporators with a capacity of 2,000 cubic meters per day were installed. Waste steam produced by the Power House turbines was used as heating steam for the MED evaporators.
During this time the facility also began producing industrial water for the Oil Refinery, then LAGO.
MSF desalination technology introduced at WEB
In 1965, the MSF (Multi-stage Flash) desalination technology was introduced at WEB Aruba with the installation of a 3,000 cubic meter per day recirculation brine MSF evaporator from Aqua Chem Inc.
Brief introduction of vertical Multi Stage Controlled Flash Evaporators
From 1978 to 1995 the vertical Multi Stage Controlled Flash Evaporators were used. This revolutionary Dutch-Hungarian design used chlorine gas for the control of marine biofouling in the condensers, intended to increase flash evaporation efficiency and to decrease operational cost. However, it turned out to be a failure. The choice was made to continue installing Aqua Chem MSF evaporators to cope with the quickly increasing water demand due to rapid economic growth in the 1990’s.
WEB imports water due to increased demand
WEB Aruba had experienced problems meeting the increasing demand for potable water. To cope with this phenomenon, drinking water was imported in 1982, 1983 and 1990 from the United States, Venezuela and Dominica.
Installation of first Reverse Osmosis facility & MED evaporators demolished
This year WEB experienced problems meeting the increasing demand for potable water. To cope with this phenomenon, drinking water was imported in 1982, 1983 and 1990 from the United States, Venezuela and Dominica.
WEB contracted a company to install a 1,000 m3/day SWRO in 1983 on a Build, Own and Operate (BOO) contract in an effort to minimize import of water. This Plate and Frame SWRO production unit stayed in operation from 1983 to 1985. There were a lot of membrane biofouling problems and this SWRO production unit never operated optimally. After 43 years of excellent results with the MSF technology, the challenging step toward SWRO had been taken in Aruba indicating the beginning of the end of the MSF supremacy era, as is often remarked in the desalination world.
In the meantime, the five MED evaporators (installed in 1958) were demolished in 1983 after being kept in production for 25 years.
Production increased with 4 new MSF evaporators (12,000 m3 /day)
During the period 1990 to 1998 WEB was forced to increase production capacity with 4 new MSF evaporators (12,000 cubic meters/day). MSF technology was chosen because of reliability, good operation experience and lack of time to evaluate new technology.
Once again, this year WEB experienced problems meeting the increasing demand for potable water. To cope with this phenomenon, drinking water was imported in 1982, 1983 and 1990 from the United States, Venezuela and Dominica
WEB’s Coral House is replaced by closed re-mineralization system
In 2007 WEB’s Coral House was replaced by an automated, pressurized lime stone re-mineralization system. This fixed bed system, was introduced mainly to strengthen the biological integrity of the re-mineralization process, eliminating the free aeration process of the distillate in the Coral House. This reduced the possibility of air-born Legionella Pneumophila bacteria contamination of the drinking water.
75 years of drinking water
Installation of 8000 m3/day SWRO unit – SWRO I
In March 2008 a new 8000 m3/day SWRO production unit went into operation. The Aqua Chem #1, constructed in 1983, was then taken out of production in June 2008 for economic reasons. It had been in service successfully for more than 25 years and was still in excellent operating condition.
80 years WEB Aruba
SWRO II is installed with capacity of 24,000 m3/day
In 2012 the SWRO #2 with a nominal capacity of 24,000 m3/day was put in operation. As a result four of the remaining MSF evaporators were put out of production. Ironically, the SWRO technology, which was rejected back in 1983 with commissioning of MSF technology, effectively pushed MSF technology out of the desalination activities of Aruba. While MSF ended the era of MED technology (the work horses of the first generation of the desalination)
100% SWRO and introduction of Electro De-ionization
This year WEB's remaining MSF evaporators were replaced by mobile SWRO units during a transitional step toward the installation of WEB’s third SWRO unit. After many years of MSF-dominated desalination, WEB has now moved to an exclusively SWRO system.
Industrial water will be produced using Electro De-ionization membrane technology.