reverse osmosis

Providing water for livestock and crop production to a rural area in Bonaire using reverse osmosis

Abstract

Water scarcity is a serious issue on many smaller islands, with population growth and the predicted impacts of climate change as driving factors. Bonaire is a small island located in the Caribbean Sea that has rural areas without grid connections to electricity and water. Agriculture, both livestock and hobby crop farming, in the Punta Blanku region used to rely on groundwater pumped from wells. Groundwater usage had to be discontinued due to salt intrusion causing the water to become brackish. Water for a large chicken farm that supplies almost all eggs for Bonaire now has water delivered by truck, but it is not reliable due to transportation issues and costs. Reverse osmosis (RO) is recommended as a reliable way to provide water to the Punta Blanku region. Water production can be powered by renewable energy and be more economically feasible with windmill power as the electrical energy source for the RO system. Surface seawater and brackish groundwater samples were tested to determine the best water source for the RO system. Total dissolved solids and electrical conductivity values determine the total power pumping need for the RO system. Using sample results and IMSDesigns, a reverse osmosis model designed by Hydranautics, it was determined that brackish water reverse osmosis (BWRO) was preferred over seawater reverse osmosis (SWRO). With Bonaire wind speeds, FreshWaterMill can easily power 200 cubic meters permeate production per day with BWRO. Additionally, less fouling is expected for BRWO than SWRO due to prefiltration by soil.

Date
2023
Data type
Research report
Theme
Research and monitoring
Geographic location
Bonaire

Perspective in resource recovery from reverse osmosis brines: the case for sustainable seawater refineries for small islands

Abstract

Reverse osmosis has become the dominant technique for desalination while at the same time there is a steady increase in reliance on desalination systems for water production globally. Resource recovery and mitigation of adverse effects from brine discharge are important factors and are increasingly being considered by researchers and industrial actors. The island nation of Aruba, with over 100 years of commercial desalination history, is used as a case study to illustrate the possibilities of shifting from centralized seawater desalination plants to seawater refineries in which freshwater is considered only one of the possible products. We identify possible economic value from desalination plants of medium scale (as is the case in Aruba) from the production of magnesium, caustic soda, chlorine-based products and rubidium and possible energy recovery possibilities through osmotic gradients and/or hydrogen storage while at the same time highlighting the insufficient potential for lithium harvesting from seawater desalination brines. We have found that the economic value from resources recovered from brine may be even larger than the value of the freshwater produced by these plants. Furthermore, reduction of salinity and quantity of brine can reduce the overall ecological impact from current brine effluents. © 2023 Society of Chemical Industry (SCI).

 

 

https://onlinelibrary.wiley.com/doi/10.1002/jctb.7469

Date
2023
Data type
Scientific article
Theme
Research and monitoring
Geographic location
Aruba