Steel residue treatment method and application in the slag pot

The steel slag in the slag pot is a simple mode of comprehensive treatment of steel slag in accordance with the guiding ideology of high value-added utilization and zero discharge of steel slag in the slag pot. That is, first, the steel slag is crushed to a particle size suitable for drying and grinding, and then coarse grinding is carried out after drying, so as to realize the separation of slag and iron (or purification of slag-containing iron particles), and then iron is extracted by magnetic separation, followed by fine grinding of steel slag in the slag pot. In this way, it is suggested that the iron should be extracted after purification and become a recycled product; in the early stage of purification, only the massive slag iron that affects the operation of the equipment (crusher) is selected. In the crushing pretreatment process, a large number of slag iron (including lump material and powder) are selected by magnetic separation, and then enter the micro-powder process line, while the selected slag iron is purified by a separate mill. This is a traditional way of dealing with.

In our new model, compared with the traditional model, most of the iron is separated and extracted in the micro-powder production line. Outside the micro-powder process line, that is, the slag iron mill mentioned above, only the selected slag iron blocks larger than 10mm (this size is determined by the grinding particle size). The proportion of the two parts of iron has not yet been calculated, estimated at 10% and 2%. The slag iron lump material in which the 2% share of iron is stored accounts for 7.1% of the original slag, and the steel slag in the slag pot is no longer picked up when it is selected (because only the lump material on the screen is magnetically separated).

These blocks are easy to dry for dry grinding and iron extraction. Even if iron is extracted by wet method, the discharge is very little, and the raw material of steel slag wasted is very little (in order to make use of this part of steel slag in mud state, at present, it can only be used as cement iron correction material after testing fineness and total iron content). In addition, the ball mill (cancel the discharge grate), the semi-autogenous mill of steel slag in the slag pot and the autogenous mill of steel slag (no discharge grate plate) can be set up for treatment. However, it is suggested that the mill with larger diameter should be used to improve the efficiency of grinding separation.

We know that the ball mill is the slag-iron separation equipment, while the dry grinding is the slag-iron separation method. The diameter of the ball mill used in the micro-powder process is larger (compared with the φ 1.2m slag iron mill), which further improves the separation effect of slag and iron. Therefore, the (coarse) mill which enters the micro-powder process after drying is the first choice. If you do not enter the coarse mill of the fine powder, then most of the slag iron powder will be magnetically separated (at this time it is convenient for magnetic separation) and fed into the grinding process of the above 2% slag iron block. At this time, the micro-powder process will be completely consistent with the traditional model, in fact, it is slightly better. Well, the equipment and method are adopted to realize the separation of slag iron in the slag pot or the purification of iron, in order to extract iron as a recovery product, and to remove iron from steel slag powder for further fine grinding. In the process of powder magnetic separation, the magnetic separator often brings out a part of non-ferrous material. The finer the powder, the more steel slag powder in the slag pot. It can be seen that the powder with fineness of about 30% is no longer suitable for magnetic separation, while the powder with fineness of 83.4% has a good magnetic separation effect, and the fineness of the powder seems to be further reduced.