Papers by Keyword: Artificial Soil

Abstract: Fly ash contains K, P and trace elements which are the essential nutrients for plant growth. Cow dung has a lot of N element. It’s a good way to mix the fly ash with cow dung according to a certain proportion as an artificial soil for plant growth. This design can offer different kinds of essential nutrient elements and make the fly ash which is difficult to control harmless. This experiment mixes fly ash with cow dung in different proportion, then with different qualities of sand. A pot experiment of planting corn is carried out to observe the morphological changes and measure the dry weight of corn, pH and EC of an artificial soil. The result shows that B0 mixture (fly ash: cow dung is 2:1 with no sand) is best for corn growth. Using an artificial soil of a certain proportion of fly ash and cow dung mixed to plant corn is feasible.

Abstract: Organic materials in soils mainly consist of alkanes, esters, aromatic compounds and plant secondary metabolites, but they are different from one another in material type and quantity, depending on the types of slopes. This paper conducts a comparitive study on soils from slopes along the Suining-Chongqing Railway. Preparing soil samples from the rocky slope, the cultivated and uncultivated slopes by using ultrasonic methods, we measured the organic materials with a chromatograph mass spectrometer (QP2100). The results show that the number and types of organic materials decrease from the cultivated slopes to uncultivated slopes and then to rocky slopes. No contaminant appears in artificial soils on rocky slopes, but it is found in natural soils. Hence, it can be concluded that the reconstruction of soils on engineering slopes is beneficial not only for ecological restoration, but also for the prevention of pollution.

Abstract: The pH, electric conductivity (EC), nutrients, heavy metals, water-holding capacity and water permeability of stabilized sewage sludge were investigated by mixing municipal sewage sludge with alkaline fly ash and slag. The results indicate that the evaporation of soil moisture increases and water-holding capacity decreases in these artificial soils with an increase of slag, and the infiltration rate of artificial soils increases to improve its water permeability by adding slag to sewage sludge. The pHs of stabilized artificial soils range from 7.5 to 8.0 for a weak alkaline soil, which tend to be neutral by adding slag to sewage sludge. The ECs of stabilized artificial soils range from 2.93 to 3.71 mS•cm^-1, indicating the higher salt content in these artificial soils. The nutrient contents of stabilized sewage sludge are up to a high fertilizer level and available nutrients increase with the increase of the ratio of slag to sewage sludge in these artificial soils. Cd, Ni, Pb, Cu and Zn for all artificial soil treatments are lower than control standards for pollutants in sludge and fly ash for Agricultural use.

Abstract: A leaching experiment was carried out over a period of 90 days to determine the manganese (Mn) and iron (Fe) leaching characteristics from artificial soils composed of sewage sludge and fly ash. The leachates of artificial soils were collected every 15 days and the concentration of manganese and iron in leachates of the artificial soil was measured. Results showed that the concentration of Fe and Mn in leachates of artificial soils got to a stable level by the end of the experiment. Moreover, plant Robina pseudoacacia and Amorpha fruticosa had different effect on the leachate Fe and Mn concentration. Robina pseudoacacia resulted in higher leachate Fe concentration, while Amorpha fruticosa resulted in higher Mn concentration. However, the leachate Fe and Mn concentrations from artificial soils was high, and it will also be transported to the surface and ground water. Therefore, some measures should be taken to reduce the concentration of heavy metals in the leachates before these artificial soils being applied on the ecological rehabilitation in mine spoil areas.

Abstract: Natural soil would be used for planting on paved area ground, but it had been replaced by the light weighted artificial soil to minimize burden of the structure. But, the existing light weighted soil had nearly capacity of fertilizer adsorption due to its glassy surface. In this study, the artificial soil prepared by sewage sludge was manufactured, tested characteristics as soil and examined on planting. The developed soil was analyzed through specific gravity, pH, water content, volatile matter and was tested on adsorption capacity of Cu. In addition, planting examination analyzed the leaf growth of planting and mouseear cress plant's pollen. As the result, the developed artificial soil showed to be color yellowish brown, bulk density 0.6g/cm3, pH 8~9, volatile matter 0.3, CEC 10, pressure strength 25 ton/m2, hydrophilic and non-toxic, which was suitable for rooftop gardening. Also, periodic growth rate and development of leaves was satisfactory as natural soil and growth and numbers of pollens were good. Consequently, the developed artificial soil with porosity and capacity of fertilizer adsorption could be usefully applicable to planting on the paved area.

Abstract: This study is about the development of porous material which shapes Ø3~8mm bead with sewage sludge by molten-salt method. The development of porous material was conducted by 2 different processes. One is made by molding sewage sludge into beads with pelletizer and then coating the beads with molten-salt and lastly sintered at 1050°C, and the other is mixing sewage sludge with molten-salt which is using synthesized zeolite, and then molding the mixture into beads with pelletizer. The molded mixture is finally sintered at 1050°C. We evaluated the value of developed material as sorbent and artificial soil for tree-planning by analyzing surface area, distribution of pore size, and cation exchange capacity(CEC). According to the results, surface coated porous material have 92.8m2/g of surface area and CEC 98.9meq/100g and the mixture sewage sludge with molten-salt have 104.1m2/g of surface area and CEC 140.8meq/100g. Thus, developed porous material can be applied to various uses as sorbent and artificial soil.

Abstract: We made artificial soil using sewage sludge, the organic wastes. The optimum composition is 50% of sewage sludge cake, 45% of illite low-quality clay, 3% of glassfrit, and 2% of other components. The surface was coated with γ-alumina. For an optimum manufacturing condition, we sintered and bubbled the plastic material with dry surface by flowing N2 gas at 800°C for 20 minutes. The developed artificial soil shows excellent characteristics; more than 60% of porosity, of 0.8 of density g/cm3, 80ton/m2 of compression, pH 7.4, cation exchange capacity (CEC) 10 meq/100g and about 2000 of hydraulic conductivity. The developed product performs 1.5 ~ 10 times better than the existing perlite in open porosity, nutrient holding capacity, proof compression and CEC. However, the bulk density is 1.5 times higher and heavier than perlite, it is not so problematic to green roof. The developed artificial soil shows positive effect on the development of ecotype leaf or the growth speed by period comparative to the common fertile soil. The number of pollens and lipid shows excellent growth on the artificial soil. The product can be applied to various kinds of plants such as flowering plants, foliage plants, trees and ground cover plant. It can also be applicable to other large amounts of plants grown on the other artificial grounds (slope, road, etc.)