4 results about "Excess nitrogen" patented technology

The invention relates to an environment-friendly gold leaching agent and an application method of the environment-friendly gold leaching agent in arsenic-containing refractory gold ore, and belongs to the technical field of hydrometallurgy. Preparing an auxiliary mixing agent from sodium carbonate and sodium sulfate according to a molar ratio of 4: 1 to 6: 1, and reacting for 2-4 hours at 200-300 DEG C under the action of excessive nitrogen to prepare a thiocyanogen complex; and cooling and crushing to obtain thiocyanogen complex powder. The effective cyanide concentration is 3%-5%, and cyanide volatilization and environmental pollution are remarkably reduced. According to the method, under the synergistic effect of biological pre-oxidation, the gold leaching efficiency is guaranteed, meanwhile, the unit dosage of sodium cyanide is remarkably reduced, the problems that a traditional cyanide method is high in toxicity and low in recovery rate of wrapped gold in the refractory gold ore are solved, and the method has high efficiency, environmental protection property and industrial feasibility and is suitable for green gold extraction of the high-arsenic and high-sulfur gold ore.

The present application relates to high-efficiency activated carbon utilization technical field, specifically, it relates to a kind of redundant nitrogen recovery process in high-purity oxygen production equipment.It includes the plate heat exchanger, precision filter, molecular sieve dryer, adsorption tower, vacuum pump, screw compressor, high-pressure storage tank and PLC control cabinet connected in sequence.The present application is preprocessed by plate heat exchanger using oxygen production equipment waste heat / cold quantity, and modified high-efficiency activated carbon is selectively adsorbed under normal temperature and pressure, and vacuum and waste heat gas regeneration and desorption gas back are combined, while obtaining purity≥99.99% nitrogen, energy consumption is significantly reduced and the connection with oxygen production main process is realized, and the technical problems of low recovery purity, high energy consumption and process interference are solved.

Systems and methods are providing for filtering a body of water, such as a lake, ocean, river or the like. A system comprises a housing having an interior configured for containing a plurality of bivalves within the water and a fluid distribution system coupled to the housing and configured to circulate water within the interior of the housing such that the water is filtered by the bivalves at a rate of about 10 to about 100 gallons of water per day per bivalves. The system provides a controlled environment to allow bivalves, such as clams, oysters and scallops, to filter the water naturally and remove materials, such as sediment, nitrogen, phosphorus, carbon, magnesium, zinc and the like. Oysters may, for example, filter pollutants from the water, remove excess nitrogen from the water and / or remove carbon from the water, which reduces the overall amount of carbon that eventually ends up in the atmosphere.

The invention belongs to the technical field of smart agriculture, and provides a rice fertilization decision-making method based on a standard ratio vegetation index, which comprises the steps of fertilization processing, spectral data acquisition, data processing and analysis, fertilization decision-making model construction, target area rice canopy spectrum acquisition, fertilization scheme generation, fertilization decision execution and the like. On the basis of unmanned aerial vehicle remote sensing spectral data of a canopy in the whole growth period of rice, a nitrogen fertilizer nutrition diagnosis and fertilization regulation model is constructed by calculating a ratio vegetation index. The model can accurately identify canopy spectrum differences under different nitrogen fertilizer treatment in the flourishing period of rice growth, and realizes accurate diagnosis of nitrogen abundance and deficiency conditions of the overground part, thereby improving the efficiency and precision of fertilization, reducing environmental pollution caused by excessive nitrogen fertilizer application, and realizing cost saving and efficiency improvement.