{"id":6193,"date":"2025-03-19T09:40:55","date_gmt":"2025-03-19T09:40:55","guid":{"rendered":"https:\/\/kysearo.com\/?p=6193"},"modified":"2025-06-12T07:56:04","modified_gmt":"2025-06-12T07:56:04","slug":"seawater-to-tap-how-desalination-works","status":"publish","type":"post","link":"https:\/\/kysearo.com\/da\/seawater-to-tap-how-desalination-works\/","title":{"rendered":"Havvand til vandhanen: S\u00e5dan fungerer afsaltning"},"content":{"rendered":"

Global freshwater resources account for only 0.325% of the earth’s total water, and desalination technology is becoming a key solution for coastal cities to solve the \u201cwater crisis\u201d. This article reveals the comprehensive advantages of reverse osmosis in terms of efficiency, cost and sustainability through technology comparison, environmental assessment and economic analysis.<\/p>\n

1. Water Intake System<\/strong><\/h2>\n

The Afsaltningsanl\u00e6g<\/strong> <\/a>adopts a cage-type water intake design\u00a0 that is 300 meters offshore and 25 meters deep. This technology controls the flow rate below 0.1m\/s, which is much lower than the average flow rate in the Tasman Sea (1.5m\/s), and successfully realizes zero involvement of marine organisms. Compared with the traditional shallow water intake, the microbial content in the deep water area is reduced by 67% , which guarantees the safety of water quality from the source.<\/p>\n

2. Pre-treatment systems<\/strong><\/h2>\n<\/div>\n
\n\n\n\n\n\n\n\n
Filtration Levels<\/th>\nTechnical Means<\/th>\nRemoval Rates<\/th>\n<\/tr>\n<\/thead>\n
Primary<\/td>\nTumbler Screen<\/td>\n99.8% suspended solids (>5mm)<\/td>\n<\/tr>\n
Secondary Anthracite<\/td>\nQuartz Sand<\/td>\n94% Algae and Colloids<\/td>\n<\/tr>\n
Tertiary<\/td>\nUltra Filtration Membrane<\/td>\nTurbidity < 1NTU<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
<\/div>
<\/div>

The sludge produced by pretreatment is centrifuged and dewatered with a solid content of 25% (original data), which improves the processing efficiency by 3 times compared with the traditional sedimentation method.<\/p>\n

3. Reverse Osmosis Technology<\/strong><\/h2>\n

The desalination plant is equipped with 36,000 pieces of 8-inch composite membranes, achieving an average daily water production of 6,900 liters from a single membrane at 60 bar pressure. Compared with earlier cellulose acetate membranes, the desalination rate of polyamide membranes has increased from 98.5% to 99.7% . Conversion of concentrated water pressure for utilization through an energy recovery device (ERD) reduces power consumption to 3.8kWh per ton of water, saving 70% energy compared to traditional distillation.<\/p>\n

\"\"<\/h2>\n

4. Post-treatment<\/strong><\/h2>\n
    \n
  1. Calcium and magnesium adjustment: food grade calcium carbonate is added to raise the hardness to 80-120mg\/L<\/li>\n
  2. pH balance: carbon dioxide injection to control the pH at 7.0-8.5<\/li>\n
  3. Disinfection treatment: 0.5ppm chloramine continuous bacterial inhibition.
    \nThis process makes the boron content of effluent water <0.5mg\/L, which is better than WHO standard (2.4mg\/L).<\/li>\n<\/ol>\n

    5. Ecological optimization of concentrated brine discharge<\/strong><\/h2>\n

    Through the diffusion nozzle system , 58% of the concentrated brine (salinity ~6.5%) was completely mixed with seawater within 2 minutes, and monitoring showed that salinity returned to its natural level 500 meters away from the discharge . This design reduces the impact on benthic organisms by 82% compared to a direct discharge pipe .<\/p>\n

    6. Engineering Innovations in Pipeline Transmission and Distribution<\/strong><\/h2>\n

    The 18-kilometer dual pipeline system uses FRP lining technology, compared to traditional cast iron pipes:<\/p>\n