The pulp and papermaking wastewater contains a large amount of cellulose, lignin, inorganic alkali and tannin, which leads to deep pigmentation, high alkalinity, high content of difficult-to-degrade substances and high oxygen consumption. The adsorption method plays an important role in the advanced treatment of papermaking wastewater and will become an indispensable treatment unit for papermaking wastewater.
Bentonite has a large internal and external surface area, strong adsorption and ion exchange capacity. The natural bentonite has been modified to significantly improve the interlayer spacing, specific surface area, adsorption performance, etc., and thus has received extensive attention in the field of water treatment.
1. Preparation of bentonite adsorption materials
The bamboo powder, bentonite, phosphoric acid and 45% by mass ratio of 7: 3:14 mixed, placed in a kneader, set temperature 170 ℃, cooled kneaded taken 30min, then placed in the sample device prepared by extrusion molding, drying. The dried sample was placed in a box-type resistance furnace (activation temperature was set at 400 ° C, 500 ° C, 600 ° C, 700 ° C, 800 ° C) for 3 h; the activated sample was placed in 10% hydrochloric acid. The solution was pickled for 2 h; then washed with water until neutral, dried, ground, and screened for 200 mesh samples.
2. Bentonite adsorption materials for papermaking wastewater treatment
Take a certain amount of bentonite adsorption material sample into an Erlenmeyer flask which is previously poured into 100mL of papermaking wastewater, adjust the pH value of the wastewater, the temperature of the wastewater, etc., shake it on the shaker, and fully react to filter the solution after the reaction. , measuring water quality indicators.
The adsorption capacity of the bentonite adsorption material sample on the papermaking wastewater CODcr changes rapidly with time. When the adsorption is close to equilibrium, the adsorption amount changes little with time. When the adsorption time reaches 60min, the adsorption and aggregation saturation phenomenon appears. No longer increased, its saturated adsorption capacity is 126mg / L.
After the bentonite and the phosphoric acid-impregnated bamboo powder are mechanically kneaded, the high-temperature activation causes the bamboo powder to be burned out and carbonized to form a large number of micropores and mesopores, which can greatly improve the adsorption performance and treat the CODcr removal rate of the papermaking wastewater. Up to 66.7%, the turbidity removal rate is over 99%.
Remote Control Excavator,Jy Amphibious Excavator Machine,Positioning Pile Excavator,Jy Amphibious Excavator
Binzhou Jinyi Equipment Co.,Ltd , https://www.jyexcavator.com