The Quarry
The Quarry is a desalination plant and bathhouse designed to provide an alternative fresh water solution in Lei Yue Mun by bringing the source of freshwater closer to its users. The project makes use of the elevation and orientation of the rock face to reduce and support its energy requirements.
The plant and spa is built with MGO concrete. This material is chosen for this project due to its salt resistant qualities, high compressive strength, and negative carbon footprint.
Lei Yue Mun is home to 4 villages with an approximate population of 4500. There is a common issue of pipes leaking, causing a significant amount of freshwater to be lost. This project examines the water crisis in Hong Kong and proposes an alternative solution for Lei Yue Mun.
Traditional desalination is expensive and environmentally damaging to the neighboring marine life. The high cost is due to the significant energy requirements involved in the process and the environmental impact is a result of disposing of concentrated brine back into the ocean.
Gravity Feed Reverse Osmosis
Making use of the elevation offered by the unique topography of the quarry, gravity feed reverse osmosis could be applied. This reduces the energy requirement to 1/4 of the standard desalination process. In addition, the orientation of the rock face allows for the effective use of solar panels to harness solar energy, further reducing the carbon footprint of the plant.
Brine Treatment
The by-product, brine, will be treated to create sorel (MGO) cement. MGO cement can withstand 10,000–12,000 psi (69–83 MPa) of compressive force whereas standard Portland cement can typically only withstand 7,000–8,000 psi (48–55 MPa). It is also carbon-positive throughout its lifetime. It only requires one round of high heat treatment (700-800°C) and absorbs carbon dioxide after its production making it carbon-positive throughout its lifetime. MGO cement is salt water resistant, making it an ideal building material for this project.
Throughout this process, other by-products such as epsomite, carnalite, and bischofite, commercial-grade spas salts can be extracted.
