Adsorption principle and instructions for use of activated carbon The adsorption of activated carbon can be divided into physical adsorption and chemical adsorption. Physical adsorption occurs mainly in the process of removing impurities from the liquid phase and the gas phase by activated carbon. The porous structure of activated carbon provides a large amount of surface area, making it very easy to absorb and collect impurities. Just like magnetic force, all molecules have mutual attraction. Because of this, a large number of molecules on the pore walls of the activated carbon can generate strong gravitational force, thereby attracting impurities in the medium to the pores. It must be pointed out that the molecular diameter of these adsorbed impurities must be smaller than the pore size of the activated carbon, so that it is possible to ensure that the impurities are absorbed into the pores. That's why we create activated carbon with different pore sizes by constantly changing raw materials and activation conditions, making it suitable for a variety of impurity absorption applications. In addition to physical adsorption, chemical reactions often occur on the surface of activated carbon. Activated carbon contains not only carbon but also a small amount of chemically bonded, functional groups of oxygen and hydrogen on its surface, such as carboxyl groups, hydroxyl groups, phenols, lactones, terpenes, ethers, and the like. These surfaces contain a ground oxide or complex which can chemically react with the adsorbed substance to bind to the surface of the activated carbon in combination with the adsorbed substance. Take a typical example: Activated carbon can react with chlorite in water to make chlorite change to chloride ion during water treatment, so as to remove chlorite from water, so that water is no longer Disgusting taste and smell. Types of activation furnaces commonly used for shell activated carbon: (1) Slip Fur: Also known as the Saddle Furnace, the refractory brick of its activation zone is a saddle type, originally a French patent. It was introduced to China by the former Soviet Union in the 1950s. After a series of improvements, it has become the most important type of granular activated carbon in China. Activation gas: water vapor. Main advantages: continuous production, large output, high quality, high temperature and stability of superheated steam, no external heating. Main problems: high requirements on raw materials, high cost, high technical requirements and high maintenance costs. (2) Simmering furnace: Activated gas: high temperature flue gas produced by coal combustion. The main advantage: simple investment province. Main problems: More fuel consumption, uneven activation, high labor intensity and large dust. (3) Earthen furnace: Activation gas: water vapor (air) Main advantages: the simplest furnace type. The main problems are low yield, low quality, original workshop style, and polluted environment. (4) Multi-tube furnace: Activated gas: water vapor Main advantages: no fuel, stable, easy to control, and large output. The main problems: uneven activation, low carbon quality, low temperature of superheated steam, easy to damage refractory tubes, and large investment. (5) Rotary furnace: Activation gas: flue gas, water vapor Main advantages: continuous operation, relatively uniform activation, suitable for the production of gas phase activated carbon. The main problems are: huge equipment, poor thermal efficiency, fuel consumption, and low quality of finished products. (6) Boiling furnace Activation gas: air, water vapor. Main advantages: good gas-solid contact, uniform activation, and small mechanical footprint. The main problem: intermittent production, easy to slag affect normal operation, fuel consumption. (7) Multi-layer oven Activation gas: flue gas, water vapor. Main advantages: large-scale equipment imported from abroad, high activation intensity and large output. Adapt to a variety of products. The main problems are: large investment, high technical requirements and high operating costs. In addition, there are a multi-tube boiling furnace, an external overflow boiling furnace, a swirling spray activation furnace, a tunnel kiln activation furnace, a swash plate type activation furnace, and the like. Wood activated carbon activation furnace: There are many types of activation furnaces. Furnaces used in foreign activated carbon manufacturing plants mainly include shaft furnaces, converters and fluidized bed furnaces. (1) Shaft furnace: Originally composed of several simple vertical combustion chambers, the walls of the chamber are made of refractory bricks. Later, the mixing was improved and the direction, speed and temperature of the gas flow in the furnace were managed. The furnace can also be used to regenerate recycled charcoal. (2) Converter: It is the most versatile horizontal activation furnace. (3) Fluidized bed furnace: Also known as fluidized bed furnace, it is a solid particle replenishing fluid blown into a suspended state. The heat transfer between gas and solid is fast, and the mass transfer rate is fast, but the particle wear is large. In the past, the powdery carbon was often produced by batch method. It has been developed into a continuous production, and can be made into ground carbon. Note the following points when using activated carbon: 1. Wash and remove dust before use, otherwise these black dust may temporarily affect the cleanliness of the water. However, it is not recommended to wash it directly with fresh tap water, because the pores of activated carbon once adsorbed a large amount of chlorine and bleaching powder in tap water, and the damage to water quality caused by subsequent placement in the filter is believed to be unnecessary. 2. It is impossible to clean the impurities in the porous pores of the activated carbon by simple cleaning. Therefore, it is important to replace the activated carbon regularly to prevent the activated carbon from losing its effect due to "adsorption saturation." And the timing of replacement is best not to wait for it to fail after replacement, in order to ensure that activated carbon can continuously remove harmful substances in the aquarium water quality. It is recommended to change 1-2 times a month! 3. The efficiency of the treatment of activated carbon is related to the amount of treatment, and it is usually "the effect of treating water with a large amount of water is relatively good". 4. After the quantitative activated carbon is used, the change of water quality should be observed frequently in the initial stage of use, and the observation results should be paid attention to as the basis for judging how long it takes for the activated carbon to be replaced. 5. When using a medicine for treating fish diseases, the activated carbon should be temporarily taken out and suspended. In order to prevent the drug from being adsorbed by activated carbon, the therapeutic effect is lowered. Commonly used distance measurement methods include tape measure distance and photoelectric distance measurement. The measuring distance of a tape measure is measured along the ground using a tape-like ruler that can be rolled up, which is a direct measuring distance. Photoelectric ranging is to use an instrument to transmit and receive modulated light waves between two points, and measure the distance according to its propagation speed and time. It belongs to electronic physical ranging. Photoelectric ranging is indirect ranging. Inch Tape Measure,Tape Ruler Measurements,Length Tape Measure,1 Inch In Tape Measure Yucheng tengxu Measuring Tool Co., Ltd , https://www.txhardwaretools.com