Experimental Research Of Producing Basic Magnesium Carbonate With Ascharite Mineral

At present, ascharite mineral resource in China is mainly used in alkaline or carbon production of borax. In recently years, with the rapid development of boron industry corresponding to produce a large amount of boron mud slag, more and more prominent caused by environmental pollution and resource prolems.This research aiming at the existing problem of ascharite mineral resource utilization, on the basis of literature review, the analysis found that ascharite mineral after effective separation of magnesium, the rest of the components are accord with the requirement of the production of non-alkali glass fiber. Therefore, based on the principle of comprehensive utilization of boron, this paper carried out a ascharite mineral as raw material, the preparation of basic magnesium carbonate in experimental study, the experiment of efficient utilization of effective separation of boron and magnesium purpose.In this paper through a series of experiments such as calcination, digestion,carbonation briquetting and pyrolysis at actionsadding calcium carbonate in ascharite mineral,the preparation of the basic magnesium carbonate process, the experimental research optimization technics conditions of assimilation:(1) The calcination experiments of ascharite mineral.Research of ascharite mineral at different temperature after calcining clinker in the activity of MgO style and weightlessness.The results show that the ore granularity in 120 microns, calcining temperature 1000 ℃, under the condition of constant temperature 0.5 h can decompose completely;Calcining clinker main phase 2MgO·B2O3 and 3MgO·B2O3, highly active low content of MgO·B2O3.And on this basis we mixing the CaCO3 briquettingcalcination with ascharite raw material, Briquetting pressure for 45 to 60 MPa,temperature 1000 ℃, about the time 0.5 h calcining temperature,calcination process of CaO and B2O3 merger replacement of MgO·B2O3, at the same time generate 3CaO B2O3 also reduces the activity of boron, avoid the loss of boron., calcining clinker activities of magnesium in the highest.(2) ascharite mineral and CaCO3 briquetting after calcining clinker carbide preparation of basic magnesium carbonate. The results show that the best optimal conditions of digestion process is: the granularity of 180 microns, 40 minutes,temperature 80℃, the digestive end-state pH is 12.4;Carbonation process of the optimal conditions is: solid-liquid ratio of 25 g/L, carbonization temperature of 30 ℃,the reaction end point pH value is 7.0; in this condition, the dissolution rate of magnesium is 78.5%;Will be carbonized liquid filtered filtrate through pyrolysis temperature 95℃, 60 min, medium speed until liquid level without air bubbles can get grade a basic magnesium carbonate(4MgCO3·Mg(OH)2·4H2O) products.And pyrolysis temperature, makes the product of basic magnesium carbonate aggregate morphology, formed by low temperature pyrolysis of filamentous transition flake or spherical morphology.In this paper, the craft of ascharite mineral mad an efficient separate of Boron and Magnesium,and the added value of the product is quite high.The results bear some theoretical significance in guiding the efficient and comprehensive use of ascharite mineral.