31results about How to "Long restore time" patented technology

The invention discloses a method for preparing an aluminum-scandium intermediate alloy by using calciothermy. The method comprises the following steps of: (1) calculating the weights of halides of aluminum, metal calcium and scandium serving as raw materials, or scandium-containing fused salt, anhydrous calcium chloride and alkali chloride required for smelting in each furnace according to the component content of the aluminum-scandium intermediate alloy; (2) after uniformly mixing a flux, adding the flux into a crucible to smelt; (3) when the flux is completely smelted, adding scandium halide and preserving the heat in a closed protective atmosphere; (4) adding aluminum and metal calcium into the smelted scandium-containing fused salt, preserving the heat and thermally reducing for 20 to200 minutes; (5) after finishing the thermal reduction reaction, slagging off, and adding an excessive amount of refining agent to remove the calcium, when the calcium content in the alloy is less than 50ppm, casting an ingot and cooling, and performing water leaching to remove slag so as to obtain the aluminum-scandium intermediate alloy. The method disclosed by the invention has the advantages of low fluorine, micro discharge, easiness in operation, steady aluminum-scandium alloy product, novelty and economy.

The invention discloses a circulating fluidized bed boiler for effectively reducing oxycarbide emission. The circulating fluidized bed boiler for effectively reducing oxycarbide emission comprises a combustion furnace, a cyclone separator connected with the combustion furnace, and a secondary air system for arranging secondary air. An outlet of the combustion furnace is connected with an inlet of the cyclone separator, a burn-out chamber is arranged at an outlet of the cyclone separator, and overfire air is introduced into the burn-out chamber. The secondary air system comprises a secondary air pipe, a plurality of secondary air vertical pipes arranged on the outer sides of a front wall and a back wall of the combustion furnace, and secondary air nozzles arranged on a water-cooled wall and connected with the secondary air vertical pipes. According to the circulating fluidized bed boiler for effectively reducing oxycarbide emission, part of flue gas is mixed with primary air and secondary air, so that NOx emission is reduced; secondary air classification in the height direction and the horizontal direction is achieved through a secondary air arrangement mode; the burn-out chamber is arranged at the outlet of the separator, carbon in fine flying ash at the outlet of the separator is burned again in the burn-out chamber, the carbon content of the flying ash is reduced, and thus the contradiction caused by reduction of the oxygen content of the combustion furnace between NOx emission reduction and the high carbon content of the flying ash can be overcome effectively.