Yixing Fanghuizi Environmental Protection Equipment Factory


Whether mercury-containing water can be treated with powdered activated carbon

Water disposal is divided into sewage treatment and sewage disposal. Sheung Shui usually refers to domestic water, industrial water, pure water, etc., which are used after manual disposal. Because the intention of sewage treatment is in contact with drinking, the adsorption function of activated carbon is relatively low and the safety function of activated carbon itself is relatively high. The sewage usually refers to domestic sewage and industrial sewage. The pollutants in the water are roughly classified into inorganic pollutants and organic pollutants. Inorganic pollutants are mainly heavy metals such as chromium, lead, mercury, etc., as well as cyanide and radioactive materials. Organic pollutants mainly refer to oxygen-consuming organic matter (BOD, COD), phenolic organic matter, phosphorus-containing and nitrogen-containing organic matter. The demand for activated carbon for sewage disposal has a good adsorption function, and different activated carbons are selected according to the different pollutants to be disposed.

Powdered activated carbon can be used to dispose of low-concentration mercury-containing wastewater. It is used in China's consumption mercury thermometer factory to raise and condense and recover mercury through saturated carbon heating. The activated carbon loaded with hydrochloric acid has a pore radius of less than 80 nm and is activated with less than 30% of water vapor. A compound suitable for removing mercury or mercury contained in liquid hydrocarbons. The adsorption of divalent mercury in aqueous solution by activated carbon is inversely proportional to the pH. When the pH value is on an acidic scale, the adsorption of mercury by activated carbon is higher. When the pH is reduced from 9 to an acidic scale, the mercury is removed by up to two times. The mercury removal efficiency of activated carbon is related to the nature of activated carbon and the activation process. The activated carbon produced by the steam method activation of wood, coconut shell and coal has a high amount of mercury removed from the solution having a pH lower than 5, such as the pH value advances, the amount of mercury removed, and the activated carbon produced by the activation of the wood by the zinc chloride method. The amount of mercury is so high that there is still a high amount of mercury removed when the forward H value is greater than 5.

The mercury removal efficiency of activated carbon is related to the participation of additives in the solution. Participation in citrate or ethylenediaminetetraacetic acid chelating agent as little as 0.02mg / L can increase the adsorption of mercury from 10% to 30%, depending on the pH of the solution and the amount of carbon, of which tannic acid is better. Participation in nitric acid is inefficient; participation in calcium ions can also advance the adsorption of mercury. When calcium ion concentration is increased from 50 mg/L to 200 mg/L, the adsorption amount of mercury is added by 10%-20%; when calcium ions are present together with tannic acid When less activated carbon is used, the amount of mercury removed is doubled; the activated carbon impregnated with metal sulfide is also very effective in adsorbing mercury.