Refractory for blast furnace and reverberatory furnace

Compared with iron and steel metallurgy, the smelting of non-ferrous metals is characterized by complex process, long flow and many kinds of furnaces for smelting. The copper production process consists of five parts: pre-furnace treatment, matte smelting, copper blowing, fire refining and electrolytic refining.

The metallurgical methods of copper raw materials can be divided into two categories: pyrometallurgy and hydrometallurgy. Since the energy consumption of copper smelting by fire method is lower than that of hydrometallurgy, it has strong adaptability to minerals and large smelting scale. The total output of copper extraction accounts for 90%, while the refined copper produced by hydrometallurgy only accounts for about 15%. In the process of copper smelting by fire, flash smelting and melting pool smelting take the dominant position. Ausmat furnace or Esha furnace of Australia, Noranda Furnace of Canada, Mitsubishi Law of Japan, Vanukov Law of the former Soviet Union and Silver law of China are the models of copper smelting by melting pool.

Bath smelting (Bath smelting) is a direct blast, quickly through the strong agitation of molten pool, gas, liquid, solid and main chemical reactions of high pyritic smelting method, this method of strengthening smelting metallurgy applies to non-ferrous metal materials melting, sulfide, oxidation, reduction, fuming and made matte converting process. Flash smelting (Flash smelting) system will be dry and fine sulfide concentration, flux and oxygen or oxygen enriched air or preheated air spray into the blazing furnace, the burden on the state of suspension under oxidation and melting rapidly melting method. The pyrometallurgy of copper includes two stages of copper sulfide concentrate matte melting and copper matte blowing.

Otto Kump flash furnaces are the world's leading flash smelters, followed by Kiefset and Inco oxygen furnaces.

The copper content of semi-finished frits made of matte and flux such as silica and limestone varies with different types of melting furnace, and the fluctuation range is generally 30%~45%.

There are blast furnace, reflector furnace and flash furnace in matte smelting furnace. After the 1970s, flash smelting to produce copper dominated, followed by reflector furnace, essa furnace, Silver method, Noranda reactor and so on.

The blast furnace of copper concentrate airtight blast furnace is widely used in many copper factories in our country, especially in small and medium sized copper factories. Copper blast furnace by the furnace top, furnace body, this bed (also known as throat), furnace cylinder, tuyere device and other parts.

During smelting, the concentrate is added into the furnace through the feeding funnel. The concentrate is added to the top layer to make it airtight and the fuel is coke. Concentrate, coke, flux and other solid materials from the top to join, furnace body side drum into the high-pressure air draught device, in the process of running up, and the materials are melted down and REDOX reaction, completing the process of smelting, slag and copper sulfur by throat mouth the top bed separation, slag composition is given priority to with SiO2 - FeO - department of CaO, upper tuyere smelting area maximum temperature of 1350 ℃. The top cover is composed of cover plate and water jacket, the side is lined with clay brick and asbestos board, and the outer steel plate. The furnace body is composed of water jacket, and the throat and bottom of the furnace are made of magnesia brick.

The reflector furnace is rectangular and is a kind of indoor flame furnace, using coal or heavy oil as fuel. The heat transfer in the furnace is not only based on the reflection of the flame, but also mainly by the radiant heat transfer of the furnace top, furnace wall and hot gas to complete the smelting process. Smelting furnace production is continuous, the smelting process in the oxidizing atmosphere and furnace temperature is about 1500~1550℃, slag by iron, silicon, calcium, aluminum oxide composition, molten dust slag sputtered on the furnace wall and top of the refractory masonry, so that the refractory masonry suffered by slag erosion and damage. The highest temperature area in the furnace is concentrated on the top of the furnace, up to 1800℃. Refractory materials used should have high temperature resistance, good thermal shock resistance, large volume density, small change of refiring line and good slag resistance. Generally, the bottom of the furnace is sintered as a whole. At present, the sintered layer is mostly made of magnesia, iron oxide and brine after ramming.

The wall of the smelting and reflection furnace adopts the magnesia brick and magnesia aluminum brick masonry of the type of anti-erosion and heat-resisting impact. In some important parts, such as the vicinity of the pulverized coal burner of the reflection furnace and the entrance of converter slag, chrome magnesia brick is selected to extend the service life. The top of the furnace, the top of the large copper smelting and reflection furnace adopts hanging furnace top, and the top of the furnace is mostly made of magnesium-aluminum brick.