Biomaterial Database

Pressurized hydrogenotrophic denitrification reactor for small water systems. 2018

Razi Epsztein, and Michael Beliavski, and Sheldon Tarre, and Michal Green

Faculty of Civil and Environmental Engineering, Technion - Israel Institute of Technology, Haifa 32000, Israel. Electronic address: epsztein@campus.technion.ac.il.

The implementation of hydrogenotrophic denitrification is limited due to safety concerns, poor H2 utilization and low solubility of H2 gas with the resulting low transfer rate. The current paper presents the main research work conducted on a pressurized hydrogenotrophic reactor for denitrification that was recently developed. The reactor is based on a new concept suggesting that a gas-liquid equilibrium is achieved in the closed headspace of denitrifying reactor, further produced N2 gas is carried out by the effluent and gas purging is not required. The feasibility of the proposed reactor was shown for two effluent concentrations of 10 and 1 mg NO3--N/L. Hydrogen gas utilization efficiencies of 92.8% and 96.9% were measured for the two effluent concentrations, respectively. Reactor modeling predicted high denitrification rates above 4 g NO3--N/(Lreactor·d) at reasonable operational conditions. Hydrogen utilization efficiency was improved up to almost 100% by combining the pressurized reactor with a following open-to-atmosphere polishing unit. Also, the potential of the reactor to remove ClO4- was shown.

UI	MeSH Term	Description	Entries
D009566	Nitrates	Inorganic or organic salts and esters of nitric acid. These compounds contain the NO3- radical.	Nitrate
D006859	Hydrogen	The first chemical element in the periodic table with atomic symbol H, and atomic number 1. Protium (atomic weight 1) is by far the most common hydrogen isotope. Hydrogen also exists as the stable isotope DEUTERIUM (atomic weight 2) and the radioactive isotope TRITIUM (atomic weight 3). Hydrogen forms into a diatomic molecule at room temperature and appears as a highly flammable colorless and odorless gas.	Protium,Hydrogen-1
D014867	Water	A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Hydrogen Oxide
D058440	Denitrification	Nitrate reduction process generally mediated by anaerobic bacteria by which nitrogen available to plants is converted to a gaseous form and lost from the soil or water column. It is a part of the nitrogen cycle.	Denitrifications
D018508	Water Purification	Any of several processes in which undesirable impurities in water are removed or neutralized; for example, chlorination, filtration, primary treatment, ion exchange, and distillation. It includes treatment of WASTEWATER to provide potable and hygienic water in a controlled or closed environment as well as provision of public drinking water supplies.	Waste Water Purification,Waste Water Treatment,Wastewater Purification,Wastewater Treatment,Water Treatment,Purification, Waste Water,Purification, Wastewater,Purification, Water,Treatment, Waste Water,Treatment, Wastewater,Treatment, Water,Waste Water Purifications,Waste Water Treatments,Water Purification, Waste
D019149	Bioreactors	Tools or devices for generating products using the synthetic or chemical conversion capacity of a biological system. They can be classical fermentors, cell culture perfusion systems, or enzyme bioreactors. For production of proteins or enzymes, recombinant microorganisms such as bacteria, mammalian cells, or insect or plant cells are usually chosen.	Fermentors,Bioreactor,Fermentor