45results about How to "Realize closed-loop recycling" patented technology

The invention discloses a method for separating and recovering valuable elements uranium, thorium, rare earth and monazite concentrate and zircon concentrate from monazite slag. The method is characterized by comprising the following steps of: acid leaching, filter pressing, washing, extraction of valuable components and treatment of filter residue. According to the invention, the monazite slag is leached by weak acid at a low temperature, and the liquid phase and solid phase are easy to separate; and meanwhile, the waste acid of residual liquid is circularly used, the discharge of wastewater is reduced, the consumption of sulfuric acid and new water as well as the wastewater treatment cost are reduced, the production cost is lowered, the recovery rate of the valuable elements uranium, thorium and rare earth is greater than 97%, and the discharge of radioactive wastewater and waste residue is avoided in the whole technology.

The invention relates to a process of recovering ammonia from ammonia-nitrogen wastewater and exhaust gas of tungsten metallurgy. The process is characterized by comprising the following steps: introducing ammonium paratungstate crystal steam and ammonia tail gas into a rectifying tower by virtue of an induced draft fan, maintaining the temperature in a range of 90-95 DEG C and condensing and recovering ammonia by using a steam separator; pumping kettle raffinate and ammonia-nitrogen wastewater which are generated after rectifying the ammonia-nitrogen wastewater into a stirring tank, adding sodium hydroxide for ammonia activation, and adjusting the pH value to 10-11; after ammonia activation, pumping to an air stripping tower, and meanwhile, introducing ammonia wastewater generated by ammonia activation into the air stripping tower, adding sodium hydroxide to adjust the pH value to 10-11.5, and controlling the temperature at 45-90 DEG C and carrying out air stripping for 2 hours; feeding ammonia gas generated in the air-stripping process and ammonia gas which is not condensed by the steam separator into a hydrochloric acid spray tower for circular adsorption to generate ammonium chloride and returning to the main process to prepare an analytical solution. The process provided by the invention is simple in process flow, stable in treatment effect, less in equipment investment, free from secondary pollution and low in treatment cost.

The invention discloses a blending method of dry coke quenching dust-removal ash in a coal blending process. The blending method comprises the following steps: transporting dust-removal ash generated by dry coke quenching every day to a coal storage yard through an ash discharge opening, arranging the dust-removal ash near low-sulfur coking coal of which the content of sulfur is less than 0.4% and low-ash meager lean coal of which the content of ash is less than 8.5% which can be blended for separately storing; according to the blending ratio required by the blending instruction of a forklift in a coal blending workshop, fully and uniformly blending the dry coke quenching dust-removal ash, low-sulfur coking coal and the low-ash meager lean coal at a weight ratio of 1:5:5 to form novel mixed dust-removal ash; conveying the mixed dust-removal ash to a coal blending bin, blending the mixed dust-removal ash and 1 / 3 coking coal, gas coal, coking coal and meager lean coal at a weight ratio of 7: 3 and rich coal to form into-the-furnace coal, crushing the into-the-furnace coal, adding water and conveying to the coal storage bin for coking coal production to replace partial meager lean coal for return blending and coking, wherein the mixed dust-removal ash, the 1 / 3 coking coal, the gas coal, the coking coal and meager lean coal at a weight ratio of 7:3 and the rich coal respectively account for 15%, 32%, 15%, 21% and 17% of the into-the-furnace coal in weight ratio. The process is convenient to operate and has the characteristic of high flexibility.