Development And Performance Characterization Of Marine Biotype Dust Suppressant And Application In Yellow River Beach Area

During the construction of the Yellow River flood control project,dust pollution and soil loss caused by siltation and sand fixation construction pose a serious threat to the production,living and health of nearby residents.A large number of studies and practices have shown that the treatment of shallow soil with dust suppressant can form a consolidated layer on the surface of soil layer that can not only prevent wind erosion,but also conserve soil and water.It is one of the most economical and effective methods to control dust pollution and reduce soil loss rate.Therefore,based on the concept of ecological environment protection,this paper studies the particle size distribution of the Yellow River beach area,establishes the component characteristic spectrum of dust,and uses BP neural network to establish the prediction model of dust emission in the Yellow River beach area.Then,according to the dust characteristics of the Yellow River beach area,the water-soluble polymer biomaterial prepared from marine biological waste shrimp crab shell and kelp was used as water retaining agent and film forming agent respectively.Then,the binder and surfactant with excellent performance were screened out,and a marine biotype dust suppressant with bonding,wetting,water retention and antibacterial effects was prepared.The morphology and mechanical properties of the film-forming agent,the moisture absorption,moisture retention and antibacterial properties of the water retaining agent,the bonding properties,thermosensitivity and curing properties of the binder,and the effect of surfactants on the wetting and permeation were studied by single factor experiments.Based on the results of the above single factor tests,the optimal ratio was obtained by the response surface model calculation,and the physical and chemical indexes and performance indexes of the dust suppressant under this ratio were tested.At the same time,the surface morphology of the consolidation layer was analyzed combined with the electron microscope scanning.In addition,the dust suppressant was sprayed in the silt area of the second section of Binzhou Flood Control Project,the engineering application effect was verified,and the corresponding benefit analysis was made.Research conclusions are as follows:(1)The particle size of dust in the Yellow River beach area is uniform,the particle surface roundness is high,and the distribution is scattered.The proportion of fine particle dust with particle size below 10 pm is 42.27%.The characteristic elements are Si,Al,Ca and Fe.It is expected that the traditional spraying method is difficult to suppress the fine-grained soil dust which is essentially silt.Through the monitoring of particulate matter emissions,the compliance rates of TSP,PM10 and PM2.5 concentrations were 91.4%,68.6%and 54.3%,respectively.Among them,the TSP concentration was most affected by the dust in the Yellow River beach area.With the help of BP neural network,the dust emission model of the Yellow River beach area was established.Through verification,this model has good prediction effect on the concentration increment of TSP,PM10 and PM2.5.(2)The single factor test showed that the morphology of the membrane prepared by the SA with mass concentration of 1%～3%is complete and the mechanical properties are good;CMCS with 3%mass concentration has good moisture retention,moisture absorption and antibacterial properties,and has certain economy;PAAS can show stable bonding properties in the low concentration range.When the soil sample is treated with 0.3%PAAS,the Shore hardness and Young’ s modulus reach the highest;Combined with the dynamic infiltration process of dust,SDS as surfactant can ensure the wetting effect and show good permeability.(3)With viscosity,anti-evaporation property,hardness of solidified layer and penetration rate as response indexes,the optimum ratio of dust suppressant was calculated by response surface model as follows:0.21%PAAS,2.62%SA,2.37%CMCS and 0.85%SDS.Through variance analysis,model verification and experimental verification,the predicted value of the model is close to the experimental value,and the fitting effect is good.Under this ratio,the pH value of the dust suppressant was 7.17,the surface tension was 34.69 mN/m,the viscosity was 89.50 mPa·s,and the penetration rate in the soil layer was 0.53 cm/min.(4)Through the performance test and field test,it is found that the ’ film-shell structure can be formed by spraying 2kg/m2 on the surface of soil sample,and the compressive strength of solidified soil sample is 2.41 MPa.The shear strength under 200 kPa axial pressure is 160.7kPa;The mass loss rate of soil samples after five simulated rainfalls was 18.35%.The total mass loss rate of soil sample is 12.11%after 100 min continuous erosion by force 3 to 7 grade wind.After 6 freeze-thaw cycles at-20～20℃,the compressive strength of the specimen is above 1.50 MPa.It could be basically degraded within 6 months after spraying.After three months of field spraying,the dust suppression efficiency of TSP,PM10 and PM2.5 can still reach 3 8.79%,22.72%and 14.13%.The cost of spraying dust suppressant is significantly lower than that of spraying water and covering dust-proof network.It has good economic and environmental benefits,and can realize the dual effect of slope protection and dust suppression.At the same time,it has the characteristics of rich raw materials and non-toxic side effects.It overcomes the defects of traditional dust suppressant and puts forward a new way for waste utilization.