The Shandong Fisheries Society recently issued its Decision on the 2026 Shandong Marine and Fisheries Science and Technology Awards. Led by GreatWay Ocean Technology Co., Ltd., the project ‘Research, Development and Application of Key Technologies and Equipment for Efficient Nitrogen Removal from Marine Recirculating Aquaculture Effluent’ stood out among numerous achievements for its technological innovation and application results, winning first prize in the technology extension category.
As the development of the ‘blue granary’ advances, industrial recirculating aquaculture is becoming a key direction for intensive marine aquaculture thanks to its water efficiency, land efficiency and high yields. However, prolonged water reuse leads to the accumulation of nitrate nitrogen under conditions of high salinity and a low carbon-to-nitrogen ratio. Conventional nitrogen-removal processes face difficulties in precisely controlling carbon dosing, large footprints for separate equipment and heavy reliance on operator experience. These constraints increase operating and maintenance burdens and expose nearshore waters to the ecological challenge of eutrophication.
The solution lies in innovation at the underlying process level. Starting from microbiology, the R&D team selectively screened aerobic denitrifying bacteria with strong salt tolerance and combined them with solid-phase slow-release carbon technology. This replaces conventional liquid carbon dosing, which is difficult to control precisely, with in-situ slow release and efficient utilization at the material surface, addressing low biological nitrogen-removal efficiency in high-salinity environments. The team also moved beyond cumbersome separate equipment to develop a ‘nested’ biological nitrogen-removal reactor. Within a single vessel, it spatially separates anoxic and aerobic microenvironments and integrates nitrification–denitrification, internal recirculation and carrier fluidization, achieving a smaller footprint, simpler piping and improved mass transfer.
An intelligent system also gives the equipment a ‘digital brain’. It combines adaptive backwashing triggered on demand by pressure conditions, high-precision online monitoring of water temperature, pH and total nitrogen, and a digital real-time monitoring platform. Together, these capabilities move operation beyond broad reliance on human experience toward precise sensing and intelligent management.
The ultimate purpose of technological innovation is to support industry. The achievement has obtained multiple invention patents and software copyrights, reached the technological maturity required for industrial application, and been successfully implemented in aquaculture and environmental protection projects in Rizhao, Yantai, Binzhou and other locations. While ensuring that effluent meets discharge standards, the system reduces the ecological load on marine waters, bringing environmental and industrial value together.
With the tides as a constant and no limit to dedicated work, GW-OCEAN will continue to pursue its founding mission and deepen research into intelligent aquaculture equipment and key water-treatment technologies. Through advanced equipment and system solutions, it will support the green, low-carbon transition of China’s marine aquaculture and contribute to protecting its blue seas.