Agglomeration Machines With Blow And Tissue Compensators

Sintering machines with air blowing through the burden layer (Fig.3.6.) Are arranged and operate as follows. Air is injected into the chambers under the pallets with a layer of charge. The entire working branch of the sintering machine is provided with a shelter for collection of burning gases and the creation of good sanitary conditions of work in the shop. The space under cover is conditionally divided into two zones: a rich gas (in the zone of intense roasting) and a poor (in the tail part) gas. In the area of the rich gas zone there are 9 blowing chambers, fabric compensators, into which air is supplied by a separate fan at a pressure of 3-4 kPa, in the area of lean gas there are 6 blowing chambers with a separate fan. The gases from under the shelter are sucked off separately by two fans, which provide a vacuum under the shelter of about 20 kPa. Rich gases with 5-7% sulfurous anhydride are sent to sulfuric acid production. In them passes 55-60% of sulfur contained in the charge. Poor gases with 2-2.5% sulfurous anhydride are either returned to blow in the first 9 chambers (work with recirculation), or after cooling from 450-500 ° C to 80 ° C, they are directed to dust collection in bag filters and discharged to the atmosphere. In blast-furnace machines there is a different unit for ignition of charge. The blowing agglomachines are equipped with three feed hoppers: for the bed, incendiary layer and main charge. The height of the bed layer is 15-20 mm, the incendiary layer 20-25 mm and the main layer 200-250 mm. The bed is made from a turn agglomerate of 8-15 mm in size. The ignition layer is a fine fraction, which is separated on the screen before loading the charge onto the agglomeration tape. The incendiary horn and fabric compensators with gas or oil burners are located between the feeders of the incendiary layer and the main charge. The lighted layer, moving together with the tape, leaves under the layer of the main charge. Under the mountain there is a single vacuum chamber, the vacuum in which is 1-1.5 kPa. Specific productivity of sintering machines with blowing is 13-18 t / (m2 s). The sulphurous gas, which is poor in sulphurous anhydride, except for its use as circulating in recirculation schemes, can be subjected to a separate treatment, after purification from dust, for example, by the citrate method, as was done at the installation of one of the US lead plants. The gas (Fig. 3.8.) Enters the absorber column with the nozzle and moves countercurrently with the citric acid solution. The absorption efficiency of sulfuric anhydride with citric acid is 96-99%. The solution after absorption is treated with hydrogen sulfide to obtain elemental sulfur. Pulp after separation of sulfur is pumped into a special chamber, where kerosene is added for flotation of sulfur. The extracted sulfur is melted and poured into castings weighing 45 kg. The regenerated citric acid solution from the flotation cell is returned to the absorption column. The capacity of the unit for gas is 2.8-4.2 m3 / min of gas, sulfur - 816 kg / day.