The chlorination roasting unit 

氯化焙烧装置

石英砂氯化提纯炉
Quartz sand chlorination purification furnace
石英砂氯化提纯管式炉炉
Quartz sand chlorination purification tube furnace

In the sand washing plant, the traditional quartz sand purification process, the vast majority of gangue minerals and gas-liquid inclusions in quartz raw materials can be dissociated or destroyed to remove, but the removal of lattice impurities is very difficult. After acid leaching, the process has reached the ultimate purification. If the amount of HF is excessively increased, the temperature or the time is prolonged, it can only cause the whole dissolution of quartz minerals, reduce the concentrate yield, and can not purify the impurity elements in the lattice. Therefore, it is necessary to develop a new deep purification process for the purification of quartz with high lattice impurity content.

在洗砂厂，传统的石英砂净化工艺中，石英原料中的绝大多数脉石矿物和气液包裹体都可以解离或破坏去除，但晶格杂质的去除非常困难。经过酸浸，该工艺达到了提纯。如果过量增加HF的量，延长温度或时间，只会导致石英矿物的全部溶解，降低精矿产率，无法净化晶格中的杂质元素。因此，有必要开发一种新的深度纯化工艺来纯化高晶格杂质含量的石英。

The main method to remove crystal lattice impurities of quartz sand is chlorination roasting process. Chlorination roasting, also known as chlorination degassing, makes use of the chemical potential gradient on the surface and inside of particles under the action of high concentration of chlorination agent to promote the diffusion of gas-liquid inclusions. There are great differences between different chlorinating agents and lattice impurities.

去除石英砂晶格杂质的主要方法是氯化焙烧法。氯化焙烧，又称氯化脱气，利用高浓度氯化剂作用下颗粒表面和内部的化学势梯度，促进气液包裹体的扩散。不同氯化剂和晶格杂质之间存在很大差异。

Different chlorination agents, such as dry hydrogen chloride (HCl), dry chlorine gas (Cl2) and mixed gas of dry chlorine and hydrogen chloride (Cl2 / HCl), were used to purify quartz sand by high temperature chlorination. The results showed that dry HCl, dry Cl2 or mixed gas of dry Cl2 / HCl had obvious purification effect on Na, Fe, K and other metal impurities, and the purification effect of dry HCl was the best;

采用不同的氯化剂，如干氯化氢（HCl）、干氯气（Cl2）和干氯与氯化氢混合气体（Cl2/HCl），对石英砂进行高温氯化提纯。结果表明，干HCl、干Cl2或干Cl2/HCl混合气体对Na、Fe、K等金属杂质有明显的净化作用，其中干HCl的净化效果最好；

Chlorination time of 2 h and chlorination temperature of 1000 ℃ are the best for the purification of Na, Fe, K and other impurities in quartz sand;

氯化时间2h，氯化温度1000℃对石英砂中Na、Fe、K等杂质的净化效果最好；

High temperature chlorination process can reduce the content of Fe, Na and K impurities, but it has no good removal effect on Al.

高温氯化工艺可以降低铁、钠、钾杂质的含量，但对铝的去除效果不好。

Chlorination purification process of quartz sand

石英砂氯化提纯工艺

Weigh a certain amount of washed quartz sand and put it into the chlorination roasting device, fill in N2 to exhaust the air, then fill in chlorination agent and mix it with quartz sand evenly, finally raise the temperature to the roasting temperature and keep it for a certain time.

称取一定量的洗过的石英砂放入氯化焙烧装置中，充入氮气排尽空气，再充入氯化剂与石英砂混合均匀，最后将温度升至焙烧温度并保持一定时间。

Principle of chlorination purification

氯化净化原理

The impurities such as alkali metals, alkaline earth metals and residual inclusions on the surface of quartz particles react with hydrogen chloride at high temperature to form gaseous chlorides, which are carried away by high temperature gas flow, so as to achieve the purpose of deep purification.

石英颗粒表面的碱金属、碱土金属等杂质和残余夹杂物在高温下与氯化氢反应形成气态氯化物，被高温气流带走，达到深度净化的目的。

It should be noted that after high-temperature chlorination, N2 is used to exhaust the roasting tail gas, and the harmful tail gas generated in the chlorination roasting process is absorbed by alkali liquor.

需要注意的是，经过高温氯化处理后，N2用于排出焙烧尾气，氯化焙烧过程中产生的有害尾气被碱液吸收。

After washing and drying, the mass fraction of Al, Fe, Na and K was analyzed.

在洗涤和干燥后，分析了Al、Fe、Na和K的质量分数。

In the case of excessive chlorination agent, the temperature and time of chlorination roasting have a key influence on the purification effect.

在氯化剂过量的情况下，氯化焙烧的温度和时间对净化效果有关键影响。