Preparation method and application of attapulgite clay dephosphorization adsorbent

Abstract

The invention relates to a preparation method and application of attapulgite clay dephosphorization adsorbent, wherein the preparation method is characterized by comprising the following steps: selecting attapulgite clay ore with the attapulgite content being more than 60 percent, stockpiling and homogenizing, then adjusting the water content of ore to be 40-50 percent by weight, and cutting and extruding by an extruder to form laminar materials; airing or drying the laminar materials, then crushing into powder and granules with different grain diameters; respectively roasting the granules at300-500 DEG C to obtain attapulgite clay dephosphorization adsorption granules with different particle grades; roasting the powder for 0.5-2 hours at 300-500 DEG C to obtain attapulgite clay phosphorus adsorption powder; or pelleting the powder to form granules, then roasting to obtain attapulgite clay dephosphorization adsorption granules. The invention provides a low-cost and high-efficiency absorption material and a method for low-concentration phosphoric water treatment.

Description

technical field [0001] The invention relates to a method for preparing a phosphorus-removing adsorbent by using attapulgite clay as a raw material and its application. Background technique [0002] The direct discharge of industrial wastewater and domestic sewage has led to a sharp increase in the phosphorus content in the water. On the one hand, the excess phosphorus in the water body comes from external industrial wastewater and domestic sewage, non-point source pollution, and on the other hand, it also has its endogenous effect, that is, the sediment in the water body will release phosphate in the reduced state, thereby increasing the phosphorus content. . Phosphorus eutrophication usually occurs in lakes, reservoirs, bays, plain river ditches and ditches, urban rivers, urban landscape water bodies and other waters with poor self-purification ability. In recent years, the continuous occurrence of red tides in the Bohai Sea is directly related to the high content of phos...

AI Technical Summary

Problems solved by technology

[0004] Patent document CN1817438 discloses a phosphorus-removing adsorbent that uses ion-adsorption type rare earth ores and clay as raw materials through batching, mixing, granulation, high-temperature roasting, acid-base activation, and drying. The adsorption capacity for phosphorus is up to 15 mg / g. However, this technical solution has long production cycle, high roasting temperature and high energy consumption.

[0005] Patent document CN101306343 discloses a method of using attapulgite clay to prepare water body phosphorus-removing granular adsorbents. The attapulgite clay is roughly selected, pulverized, sieved and then stirred with water. The high-pressure densifier uses a mold to granulate the mold, and the high-temperature Roasting in an electric furnace to make water body phosphorus removal granular adsorbent, but in this technical scheme, it is required that the content of dolomite in the attapulgite clay raw material used is greater than 20%, and the calcination temperature is 600-800°C. On the one hand, the calcination temperature If it is too high, the specific surface area will be reduced, and the energy consumption will be too high; Make the material strongly alkaline and reduce the adsorption of phosphorus