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The phosphorous ore resources of our country are abundant, but high-rich grade ores are few. As the fast development of the phosphorus chemical industry and phosphorus ore exploited disorderly and wasted seriously, the reserve volume of premium phosphorous ore of our country are falling sharply, the utilization of middle or low grade phosphorous ore has already become the key of industrial development, which restrict the development of phosphorous chemical industry. Meanwhile, in China, serious lacking of soluble potassic resource, potassic fertilizer still depends on import. However, the reserve volume of insoluble potassium resource in our countries is very abundant and widespread. Because the high consumption of energy and poor benefits, the popularization of potassic fertilizer, which are prepared solely based on potassium ore, become very difficult. Using combination of the K-feldspar potassium extraction with the uses of middle or low grade phosphorus of ore, soluble potassium salt and phosphoric salt are produced synchronously, the rational utilization of K-feldspar and phosphorus ore resource has come true, which has great economic value and scientific meaning.This text use ground phosphate rock, coke and potash feldspar as main materials, through grinding, measuring and mixing, then roast under the high temperature. Regard reactivity ratio of phosphor and dissolving rate of potassium as the major indicator, it also investigates reductant consumption, calcination temperature, roasting time, mol-ration of silicon divided calcium, assistant kind and assistant addition level impacting on reaction index.Through the experiment, conclusions can be listed as follows:(1) In the ground phosphate rock-coke system, with the increase of the addition level of reductant consumption and reactivity ratio of phosphorus have improved, when reductant consumption is 45% of the phosphorous ore, the suitable calcination temperature is 1250℃and roast time is 2.0 hour, at this moment,86.97% is the greatest rate to the reactivity ratio of phosphor.(2) On the basis of determining the ground phosphate rock-coke system reaction condition, adding the K-feldspar to the system. Through investigating the impact of on the experiment, result is obtained:when mol-rate of calcium and silicon is 2.0, 54.64% is the highest rate as the intersection of soluble potassium citrate. At this moment, the reactivity ratio of phosphor is 82.83%.(3) Through orthogonal, the excellent scheme of the ground phosphate rock-coke-K-feldspar reaction system is:calcination temperature is1250℃, roast time is 1.5 hour, calcium/silicon ratio is 2.0, and reductant consumption is 40% of the phosphorous ore.(4) On the basis of excellent scheme of reaction system of ground phosphate rock-coke-potash feldspar, influence of producing rate to potassium on flux type and dosage to ground phosphate rock-coke-potash feldspar system is investigated specifically. The result shows:with the increase of the addition level of assistant consumption, the reactivity ratio of potassium have improved. Under the situation of identical addition of assistant, confirming optimal flux is CaCl2, suitable addition level is 40% of the K-feldspar quality.(5) The ultimate consequence point out:for the reaction system of phosphate rock-coke-potash feldspar, calcium/silicon ratio is 2.0, calcination temperature is 1250℃, roast time is 1.5 hour, and reductant consumption is 40% of the phosphorous ore, then the reactivity ratio of phosphor exceed 90%, the total reactivity ratio of potassium near 96%, and the 93% of total potassium is escaped on gaseous state. The potassium content is only 0.18% in remainder. This circuit can simplify the extract course with water or citrate acid, and reduce the consumption of energy comparatively.
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