Natural gas is used as the main raw material, and channel steel is used as the flame contact surface to produce carbon black. This kind of carbon black is called channel black. Compared with furnace black and thermal black, its particles are finer and its specific surface area is larger. At the same time, due to the specific production method, its surface is oxidized and contains more oxygen-containing functional groups and is acidic. Such carbon black particles have a low degree of agglomeration. Because it contains more oxygen-containing functional groups, it can delay the vulcanization speed of rubber, improve the weather resistance of rubber, and endow ink with good fluidity and printing performance. The trough method is that in a naturally ventilated fire room, natural gas or coalbed methane is incompletely burned through thousands of porcelain burners and air to form a fishtail-shaped diffusion flame, which is in contact with the slowly reciprocating channel steel through the flame reduction layer The carbon black produced by pyrolysis is deposited on the surface of the channel steel, and then the scraper on the funnel scrapes the carbon black into the funnel, and then it is output by the screw conveyor and granulated to make the finished carbon black. Channel black has excellent reinforcing properties, especially suitable for natural rubber (NR), and has been widely used in the rubber industry. However, due to the rising price of raw gas and the serious environmental pollution caused by production, its production was basically stopped in the 1970s. However, channel black is the only type of carbon black for rubber that can be used in contact with food. Currently, channel black is produced in a few factories.
Gas-mixed carbon black is named after the mixture of solid or liquid hydrocarbons gasified and combustible gas (also known as carrier gas) as raw material. The production process of gas-mixed carbon black is generally the same as that of channel carbon black except for the production device of raw material gas.
Commonly used solid raw materials are crude anthracene, and liquid raw materials are anti-corrosion oil and anthracene oil. Commonly used carrier gases include coke oven gas, city gas, water gas, blast furnace gas and so on. The key to the gas-mixed carbon black production process is how to gasify solid or liquid raw materials and mix them with carrier gas. One is to use a gasifier, and the other is to gasify hydrocarbon materials in a tube furnace. After the mixed gas generates carbon black, it can be divided into gas-mixed carbon black with grooves and gas-mixed carbon black without grooves according to whether channel steel is used for cooling and collecting in the fire room. Gas-mixed carbon black was originally used in radial tires, sidewalls, inner tubes, rubber shoes, rubber hoses, advanced seals, and high-grade gasket products. The product is suitable for natural rubber and various synthetic rubbers. It is easy to disperse and can endow the rubber with high elasticity. The extrusion speed is fast, the mouth expansion is small, and the surface of the extruded product is smooth. The vulcanized rubber has good high temperature resistance and thermal conductivity. Reinforcing properties, flex resistance, elasticity and recovery are also better. Typical product indicators iodine absorption value 80g/kg oil absorption value 98cm3/100g, 300% modulus stress 10.2Mp, similar to the new process furnace carbon black N330 product.
In recent years, with the introduction and absorption of new process furnace carbon black, China's carbon black production has entered an era of unprecedented development. The new process carbon black relies on its own high level of industrial automation, stable quality, high yield, low manufacturing cost, and environmental protection. The advantages of high level and large production capacity have gradually eliminated gas-mixed carbon black products from the tire rubber market, and lost tire rubber, which accounted for 90% of the carbon black market. Not many manufacturers use the unique production method of aerated carbon black. Its surface is oxidized and contains more oxygen-containing functional groups, which is acidic and easy to disperse. It can endow the ink with good fluidity and printing performance as a pigment. Carbon black is retained. But at present, the brand development of aerated carbon black in my country is very backward, and there is no international or even domestic famous brand. Instead of aerated carbon black brands, there are various carbon black brands for pigments. Seriously hindered the development of gas-mixed carbon black.