Study on preparation and properties of eco-friendly dust suppressant

Abstract: Particulate matter pollution is a serious problem in north China. One of the important sources is the bare farmland on the outskirts of the cities. To effectively control wind erosion and improve the quality of the urban environment in north China an eco-friendly dust suppressant ("SY" dust suppressant) was prepared with suaede salsa seed cake, a kind of agricultural and sideline product as main material, adding suitable amount of sodium dodecyl benzene sulfonate, sodium carboxy methyl cellulose, and polyvinyl alcohol, et al. In order to discuss the performance of the "SY" dust suppressant, a study was carried out to compare "SY" dust suppressant with plant gum dust suppressant ("ZW" dust suppressant) and eco-efficient dust suppressant ("GS" dust suppressant) in various performances, including primarily the microstructure characterization of "SY" dust suppressant bonded soil particles, as well as the viscosity, moisture retention, water stability, the ability of anti-wind erosion, the effects on seed germination rate, and on soil of the three kinds of dust suppressant. The microstructure of "SY" dust suppressant adhered to soil particles showed that the "SY" dust suppressant could cement loose soil particles together and form a smooth and flat consolidation layer. The structure could effectively protect the fine particles on the surface of the soil being blown away. In the three kinds of dust suppressant, the viscosity of "SY" dust suppressant was the highest at 5-45℃, which was 10 to 17 times higher than the other two dust suppressants. The reason may be that the powder of suaede salsa seed cake went through high-temperature stewing in water bulking to biomass solution, and then crosslinking took place between the biomass solution and sodium carboxymethyl cellulose, which improvedthe bonding performance of the "SY" dust suppressant. The moisture content of the consolidation layer after spraying "SY" dust suppressant fell at the slowest pace. The moisture content fell to 4.2% after 72h, while it was still above 4%. "SY" dust suppressant extended the time of moisture in the consolidation layer by 18 hours more than the other two kinds of dust suppressant. A "SY" consolidation layer could fight 4 times the rain erosion than the other types, indicating that the "SY" dust suppressant had excellent water stability. The water stability of the three kinds of dust suppressant decreased in the order: "SY" dust suppressant> "GS" dust suppressant>"ZW" dust suppressant. The cumulative loss of soil particle on a per unit area of samples which were sprayed with "SY" dust suppressant was the minimum. The losses were all less than 0.7 g/m2, and it could improve the efficiency of dust suppression by more than 99%. Besides, because the "SY" dust suppressant contained organic matter and small amounts of nitrogen, phosphorus, potassium, magnesium, calcium and so on which were included in suaede salsa seed, spraying "SY" dust suppressant on soil samples could improve the soil nutrients needed for plant growth and promote the growth of plants. The experimental results showed that spraying "SY" dust suppressant on soil samples could increase the total nitrogen content by more than 100 times, and the content of organic matter, bicarbonate alkalinity, available potassium, exchangeable calcium, and exchangeable magnesium increased at different levels compared with spraying the same amount of tap water. It can be found clearly from the experiment of the seed germination rate that spraying "SY" dust suppressant on soil samples could improve the germination rate of seeds up to 95.6%, and the seedlings grew best. In addition, spraying "SY" dust suppressant on soil by the amount of 2 kg/m2, the cost was 0.33 RMB per square meter, when considering the expenses of labor, the cost could be controlled to about 0.5 RMB per square meter.