Step 1: Exhaust gas purification
The flue gas exported from the electric furnace passes through the fume hood, main flue gas pipeline, cools down through the cooler and then enters the cyclone separating dust collector, and then passes through the cloth bag dust collector. The flue gas enters the bag filter through the fan, the dust is trapped down by the inner surface of the filter bag, and the purified flue gas which meets the environmental protection standard is discharged from outside the filter bag and rises to the top of the dust collector to be discharged into the atmosphere through the emission port.
Step 2: micro silica fume collection
When the equipment running resistance or time reaches the set value, the ash unloading process starts. Using the negative pressure of the front section of the main fan, the dust cleaning process of each compartment of the bag filter is realized through the switching of the anti-suction duct and inlet and outlet duct valves, and the recovered dust is sent to the micro silica fume homogenizing device by the fan through the ash conveying duct.
Step 3: Encryption of micro silica fume
The initial density of micro silica fume collected through the bag filter is only 150-200kg/m3, which costs a lot in transportation. Therefore, after encryption, the micro silica fume is in the shape of a sphere, and the specific gravity of the pile is increased from about 0.2t/m3 of bulk micro silica fume to 0.3~0.6t/m3, which can reduce the packaging and transportation cost by about 30~60%. At the same time, the loading and unloading efficiency is improved, storage space and land area are also reduced, and the production site dust phenomenon is greatly reduced, improving labor conditions and the environment.
Future trends of micro silica fume in China
In recent years, due to the country’s attention to environmental protection, gradually strengthen the management of polluting enterprises, especially the increase in domestic demand for high-strength concrete, many ferroalloy production enterprises equipped with dust collection equipment, and the development and introduction of encryption technology. China’s micro silica fume products are developing rapidly. High-strength concrete, micro silica fume shotcrete, silica powder mortar, low-cement casting materials and other scientific research achievements have passed the ministerial or provincial and municipal technical appraisal, and have been applied in many projects, with remarkable technical and economic results.
With the development of national economic construction and the vigorous construction of China’s 18,000 kilometers of coastline (deep-water harbor terminals, cross-sea bridges, offshore drilling platforms, etc.), the application areas of micro silica fume will certainly be further expanded. In the face of such a huge market, the production management, quality control and supply assurance system of micro silica fume have put forward higher requirements, not only to ensure the production and supply of large quantities, but also to achieve modernized, scientific and refined management in the process, so as to achieve the real sense of turning “waste” into treasure.
