Results of an Ocean Trial of the Symbiotic Machine for Ocean uRanium Extraction

Abstract

Amidoxime-based adsorbents have become highly promising for seawater uranium extraction. However, current deployment schemes are stand-alone, intermittent operation systems that have significant practical and economic challenges. This paper presents two 1:10 scale prototypes of a Symbiotic Machine for Ocean uRanium Extraction (SMORE) which pairs with an existing offshore structure. This pairing reduces mooring and deployment costs while enabling continuous, autonomous uranium extraction. Utilizing a shell enclosure to decouple the mechanical and chemical requirements of the adsorbent, one design concept prototyped continuously moves the shells through the water while the other keeps them stationary. Water flow in the shells on each prototype was determined using the measurement of radium adsorbed by MnO 2 impregnated acrylic fibers contained within each enclosure. The results from a nine-week ocean trial show that while movement of the shells through the water may not have an effect on uranium adsorption by the fibers encased, it could help reduce biofouling if above a certain threshold speed (resulting in increased uptake), while also allowing for the incorporation of design elements to further mitigate biofouling such as bristle brushes and UV lamps. The trace metal uptake by the AI8 adsorbents in this trial also varied greatly from previous marine deployments, suggesting that uranium uptake may depend greatly upon the seawater concentrations of other elements such as vanadium and copper. The results from this study will be used to inform future work on the seawater uranium production cost from a full-scale SMORE system.

Uranium extraction from seawater: material design, emerging technologies and marine engineering

“…334 Taking that into account, a two-part system called the Symbiotic Machine for Ocean uRanium Extraction (SMORE) (Fig. 40B and C) was proposed by Haji and colleagues, [335][336][337][338][339][340] to decouple the mechanical and chemical requirements of adsorbents for uranium harvesting from seawater. The SMORE concept involved the structure of an offshore floating wind turbine that was utilized to provide the mooring and structural support for an autonomous, offshore uranium-harvesting platform.…”

Flow-Assisted Selective Mineral Extraction from Seawater

“…To accomplish this goal, the system is perturbed away from the equilibrium mixed state by applying electric fields as in electrodialysis . Another approach is to introduce a new type of interaction by using adsorbents that bind favorably to specific components in the mixture. − While these methods have proven successful in a variety of applications, they remain beset by technical limitations such as the ineffective separation of similarly charged ions, limited durability of membranes and adsorbents, or the energy input necessary for sustaining nonequilibrium conditions and driving toward separation. , …”

Metal–Organic Framework-Intercalated Graphene Oxide Membranes for Selective Separation of Uranium

“…With the increase in the environmental and energy crises, the nuclear power has attracted much attention as a type of clean energy. − However, the development of nuclear power is accompanied by the consumption of uranium resources and accumulation of radioactive waste . Unfortunately, the conventional uranium resource on the earth may be depleted within one hundred years, and the radioactive elements from nuclear waste are fatal to the environment and human health. , Therefore, for recycling and utilizing uranium as well as protecting the human health and the environment, it is necessary to extract uranium from the seawater rich in uranium resources and radioactive waste. , The existing separation and extraction methods of uranium mainly focus on the electrochemical method, , solid-phase extraction method, − membrane separation, − photocatalysis, − and so on. However, most of the traditional methods face problems such as secondary radioactive pollution, high energy consumption, and low efficiency .…”