|
NEW BLUEHILLS REVERSE OSMOSIS PLANT
|
Better Taste!....Better Quality!...Greater Reliability! It's Happening Now! |
The new BlueHills Osmosis Plant is now fully operational providing some 5 million gallons of water per day to customers
Eventually, the Corporation will begin to rely less on barging of water as water supply for New Providence residence will be mainly through R.O. plants which is guaranteed to provide better taste, better quality and greater reliability.
Other plants planned for New Providence include, one at Perpall's Tract and later one for eastern New Providence.
THE USE OF REVERSE OSMOSIS IN THE FAMILY ISLANDS
Reverse Osmosis is a method of desalination which employs a semi-permeable membrane (usually a thin plastic film) to physically separate high quality water from water the contains salts and other types of impurities including micro-organisms. Pressure is applied to the saline or feedwater side of the membrane and purified water passes through and is collected on the other side of the membrane. The unwanted impurities on the salty side are then flushed away. Seawater can be used as a source of feedwater, and therefore this means of producing high quality drinking water can be used almost anywhere in the world. The drawback is that the feedwater usually has to be cleaned up, or filtered, before it can be passed though the membrane and energy is required to create the pressure needed to push the water molecules through the membrane.
The principle of reverse osmosis is very simple but in practical terms it requires high maintenance and a sound technical understanding of the processes involved. Reverse osmosis has many applications. It is used to desalinate seawater or brackish water for drinking and it is used to produce high quality water for kidney dialysis, and many other chemical processes. Even wastewater can be treated by this process.
A basic reverse osmosis plant comprises a feedwater supply, a pretreatment filter system, a high pressure pump, and membrane, facilities for product storage, and a brine disposal system.
In order to protect the membranes which are expensive and vulnerable items, the pretreatment system can involve a number of different procedures to make the water safe for drinking other procedures are employed on the downstream side of the membranes.
Small plants usually come in the form of a prefabricated package, but the individual components can be purchased and assembled to meet specific requirements.
In the Bahamas the use of reverse osmosis is widespread. Hundreds of small plants are used in boats to produce water and plants are now common in many households. Most of the bottled water supplies in the Bahamas is produced by reverse osmosis. Persons who live where there is no piped supply of water, and the groundwater quality is poor, have a choice of collecting rainwater of purifying their groundwater by means of reverse osmosis. Where the rainfall is low or very seasonal reverse osmosis is a more reliable option and those that do not want to deal with and understand the technology involved can pay a person or a company to operate and maintain their plants. Hotels, marinas, and restaurants use reverse osmosis throughout the Bahamas. The biggest plant in use is the 2 m million gallon per day plant operated by Waterfields in New Providence. There are a large number of companies and individuals selling reverse osmosis equipment in the Bahamas and it is easy to procure and install a plant. What is not so simple is operating and maintaining the plant successfully and the cost of the water is considerably higher than that of traditional sources such as groundwater.
The reality of reverse osmosis in this island environment is that it is a godsend for the Bahamas. This is because there are many inhabited islands that do not have adequate water resources to meet the needs of the residents, and there are many situations where water cannot be piped in from other nearby source areas. In some locations rainwater and groundwater sources did meet water demands for many years but development and particularly the growth of tourism has changed this situation. Reverse osmosis already provides water for the residents of Grand Cay, Moores Island, Black Point and Farmers Cay, and plans are being finalized for plants to be installed in Bimini, Long Island, San Salvador, Inagua, and Ragged Island. Other islands with Bahamian communities that will require the use of reverse osmosis include Great Harbour Cay, Staniel Cay, Acklins, and Long Cay. Some islands like the off-shore Abaco cays that do not have any freshwater resources could obtain their water from the mainland by means of underwater pipelines, like Harbour Island and Spanish Wells in Eleuthera, but until the mains are laid small reverse osmosis plants are used by the commercial enterprises on these cays. Little Exuma and Barreterre do not have good freshwater resources but water could be supplied from Great Exuma by pipelines. Alternatively, local reverse osmosis plants could be utilized.
In early days New Providence could meet its water demand from groundwater sources, but this situation has changed because of the growth of the population and tourism, and changing habits of water use, and there are islands where this scenario will probably be duplicated in the future. Examples are Eleuthera, Great Exuma, and Rum Cay. Acklins has good water resources but unfortunately these are located well away from the population centers and there is a need for the use of small reverse osmosis plants in sectors of the island.
In the foreseeable future approximately twenty (20) populated islands will require water produced by desalination, but this number could easily increase with development or growth in population. Presently the best means of desalination on the scale required is reverse osmosis, and because of various technical considerations the best method of getting the required plants installed and operated is by means of private companies with the appropriate experience. All Bahamians can, and probably do, benefit from the use of reverse osmosis, and what is now needed is a true appreciation of the value of good quality water, because this water is not cheap. Technology is constantly changing, however, and the situation described above could quickly change. What will never change is the growing demand for water.
| 
