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Cynodon dactylon has become a dominant riparian species in the reservoir region after the Three Gorges project was finished. In order to determine the effect of the species in soil conservation and slope reinforcement and the variation over time, the soil erosion resistance and shear strength of plants soil-root systems were tested during different seasons in a year through control experiment. Results showed that C. dactylon roots enhanced significantly soil conservation and slope reinforcement. The tensile strength of C. dactylon roots reached from 65.34 to 91.22Kpa/mm2 after three to twelve month growth, so did the soil erosion resistance coefficient from 0.34 to 0.86, shear strength from 20.82 to 25.98Kpa increasing by 39.62%, 154.90% and 24.74% respectively. We conclude that the temporal dynamics of C. dactylon roots influenced the performance of soil-root system in soil conservation and slope reinforcement.

The soil-root system formatted by plant roots and soil has a good effect in soil reinforcement and slope protection. Setaria viridis is a common species distributing in the three gorges reservoir region. In order to determine the performance of the species in soil reinforcement and slope protection and its variation characteristics on the water-level-fluctuation belt, we tested the tensile strength, anti-scouribility, anti-erodibility and shear resistance of the community soil-root systems. The results showed that the root system of S. viridis community grew better with the increase of altitude under the influence of water level fluctuation. The soil - root system of S. viridis community has an effect on soil reinforcement and slope protection. Its tensile strength of roots ranged from 60 to 90 Kpa/mm2,and its anti-scouribility enhancement coefficient, soil anti-erodibility enhancement coefficient and shear strength of soil-root system reached 0.15 to 0.90, 0.30 to 0.73, and 9 to 24 Kpa respectively. Its effects in soil reinforcement increased with the altitude increases. The correlation analysis indicated that the effects related significantly with root biomass. It is concluded that spatial changes of effects of soil-root systems in its soil reinforcement and slope protection might result from difference of root growth caused by water level fluctuation.

Through the analysis and study the properties, characteristics and present conditions of the flue slime of blast furnace, a suggestion was made of recovering carbon and iron concentrate from the flue dust using a beneficiation technology consisting of magnetic separation-gravity separation-flotation. The laboratory test achieved good technical and economical results, reaching the expected effect. The technology can be applied in production and popularized.

The tailings and slag based mine filling cementitious materials was prepared by sodium silicate and sodium hydroxide alkali-activated tailings and slag. Through the test that the cementing materials in the best ratio of raw materials: when slag and tailings admixture is 1.25, the content of NaOH was 50%, the amount of sodium hydroxide for 50%, water cement ratio of 0.22, under the condition of normal temperature curing 7 days, eventually making a compressive strength of 52.3MPa cementing materials.

For chengde iron tailings pulp, make the pH value, pulp density, density of tailings determination, then carried on the laboratory test, the pulp density 3.84%, use the 2 # flocculant : 1.2 g/m3, tailings concentrated overflow water suspended solid content is 216 mg/L, meet the national discharge standards, by the test it can be used to production water.

In order to better exploit and utilize the oolitic hematite ore resource in Zhangjiakou region, staged grinding-separation process consisting of high intensity magnetic separation(HIMS) and reverse floatation was adopted in the beneficiation test on the regionally representative oolitic hematite ore of Longyan Iron Mine, Xuan Stee1. The test results indicate that，with Slong pulsating high gradient magnetic separation as HIMS equipment，with NaOH，starch，CaO and TS as flotation reagents，and at a grind of 65％ -200 mesh for the primary grinding and 95％-200 mesh for the secondary grinding，an iron concentrate grading 62.34％ and having an iron recovery of 53.07％ can be achieved after two stage HIMS and one roughing—one cleaning reverse flotation.

Through the analysis and study the properties, characteristics and present conditions of the flue slime of blast furnace dust, a suggestion was made of recovering carbon and iron concentrate from the blast furnace dust using a beneficiation technology consisting of gravity separation-flotation. The laboratory test results indicated that it can obtain the iron/carbon concentrate with a grade of iron 53.41%, carbon 65.21% at a recovery rate of iron 51.33%, carbon 69.29%. This mineral processing technology achieved good technical and economical results, reaching the expected effect. The technology can be applied in production and popularized.

In order to broaden the utilization of desulfurization gypsum in China and achieve the direct usage of desulfurization gypsum, in this paper, Polycarboxylic acid water-reducer (HC), Naphthalene sulfonate formaldehyde polycondensate (NF) and Sulfonated melamine formaldehyde resin (SM) were selected as water reducer to modify desulfurization gypsum. The experiment results are as follows: SM water reducer has little effect on setting time of desulfurization gypsum, although it is helpful to increase the strength of the gypsum-sample, however, compared with HC and NF, it has no obvious effect. About HC water reducer, it has obvious effect on setting time of desulfurization gypsum, so does it to desulfurization gypsum strength, but, higher water using of normal consistency will do adverse effect on the whole with the increase of the dosage. NF water reducer has the similar effect on setting time and sample's strength on desulfurization gypsum with HC, but the dominant changes have no discipline among different mixing amounts with these two water reducer. Lower water using of normal consistency benefits the retention of the sample's strengths.

Based on the chemical analysis and mineral composition research, a series condition tests were done with ore grade 1.45%.The optimum conditions were grinding fineness -0.074mm65%, collector as butyl xanthate- Ammonium aerofloat butyl(3:1) with 100g/t ,activator as sodium sulfide 200g/t,foaming agent as 2#oil of magnetite 30g/t. The result of tests showed that the grade of copper concentrate and the copper recovery are 8.98% and79.50% by adopting a circuit of one rough flotation, two scavenger.

As high-grade refractories raw material，kyanite is widely used and the market demand is increasingly greater. To identify the process mineralogical properties of kyanite from Heibei so as to provide a mineralogical basis for its chemical composition, mineral constituent，ores texture and structure and so on. The results show that: the kyanite Al2O3 21.50%, SiO2 52.87%, using high intensity magnetic separation-gravity separation-flotation folwsheet. Experiments show that, the grinding fineness of -200 mush 65%, with strong intensity magnetic separation, magnetic concentrate by shaking the low intensity magnetic separation，we can get magnetite, garnet, biotite and phlogopite four concentrates, strong magnetic ore tailings consolidated by a rocking bed mud thrown first, refined through flotation, won Kyanite concentrate grading about 56.11% at a recovery of 49.90%.

With the development of industrial production, kyanite's position is more and more important in social production, This paper introduces the physical and chemical characteristics of kyanite, technology characteristics，and has made the quite overview to the application of kyanite and its industry standards.

As high-grade refractories raw material，kyanite is widely used and the market demand is increasingly greater. The kyanite in Hebei is complicated，main chemical composition is SiO252.87％、A120321.14％. The result of investigation on mineral processing technology show that desliming has a great influence on kyanite, especially acid process, the suitable lower limit particle size for desliming is 20μm. Magnetic separation process may remove iron-bearing minerals，and the iron removal rate is 87.78％．The optimum condition for magnetic separation is magnetic field conditions 1.0T. Base on the research, we can get concentrate with a grade of A120358.37% and a recovery of A120356.02% if we adopt magnetic separation and flotation technology.

The fine oolitic hematite ore (＜20μm) is easily covered by the ore slime, therefore, it is processed very difficultly with traditional crafts, for example, gravity treatment, magnetic separation, and flotation. The tiny iron ore is unable to recycle effectively, bring about a large of useful minerals running off. It is indicated that the selective flocculation is effective separation craft in many research works. The good dispersion of fine particles is the selective flocculation essential condition, the excessive dispersion will destroy the selective flocculation, at the same time it can be influenced by the water quality, pH, the mixing time, the shear rate and the dispersing agent use level. In this article, to oolitic hematite ore, the chemistry dispersion research is conducted to provide the foundation for further selective flocculation separation.

Based on the coal petrology character of Taixi anthracite, the selective flocculation-flotation preparation of super clean coal is studied. The influences factors of the type and dosage of dispersant, the type and dosage of flocculant, pulp density etc etc on its effect is analyzed, and, through the orthogonal experimental methods, the salience order, interaction, and the optimum combination of the main factors is revealed. The finally test results indicate that we can obtain an ash about 1.29% at a yield of 41.85%％ super clean coal, thus will provide basis for the future super clean coal industrialization.

This paper discussed the experimental resuhs of exploiting brick materials with iron tailing materials in Tanshang area. Through preparation of iron tailing bricks, the technical flow and production proportion was obtained. The results show that a burning-and steam curing-free brick product with a compressive strength of 28.30 MPa and Flexural strength of 5.63 MPa as the following: iron tailing; fly ash; sand; CaO; gypsum; cement. And long-term properties of a burning-and steam curing-flee brick is also studied by experiments in this paper. Put forward a new technique of making materials with iron tailing. At the same time, the micro mechanism of iron tailing brick was also studied with X-Ray Diffraction (XRD) and Scanning Electron Microscope(SEM).

Difficult in soil-water characteristic curve achieved, existence of non-uniqueness and indistinct in influence of unlinear deformation characteristics of soil about density and water content, deformation characteristics of unsaturated soil were studied difficultly with general triaxial test, thus direct application of unlinear Duncan-Chang model in unsaturated soil was restricted. General triaxial tests with combined dry density and water content are carried out, changing rules of parameters of Duncan-Chang model are summarized, mathematical functions between dry density, saturation and parameters of the model are established. Analysis shows that deformation characteristics of unsaturated clay are influenced obviously by saturation and dry density. Among them, the larger the saturation, the higher strain becomes under the condition of the same dry density and main stress difference, and the less the dry density, the higher strain becomes under the condition of the same saturation and main stress difference. Moreover, the main parameters of Duncan-Chang model keep close correction with dry density and saturation, and the both mutual effect can be expressed by multiplication. This shows that mechanical characteristics of unsaturated soil can be studied with general triaxial test, thus it will be used easily in project.

Based on the study on the characteristics of a limonite ore, research was made on single reverse flotation for Xinjiang limonite ore. The test results indicate that we can obtain an iron concentrate grading about 54.07％ at a recovery of 62.65％ from an iron ore assaying around 41.85％ iron，rather good metallurgical performances.

The grade of the crude hematite-limonite ore is 39.79%. The main metallic minerals are hematite-limonite. Hematite has disseminated structure distributed in the gangue. Limonite was inlayed as stars in hematite. Due to their fine dissemination and close association with gangue minerals, the hematite and limonite particles are hard to be fully liberated, bringing difficulty in their separation. Staged grinding-separation process consisting of high intensity magnetic separation and reverse floatation wag adopted in the beneficiation test on the regionally representative hematite—limonite ore resource. At a grind of 70.0% -200 mesh for the primary grinding and 98.7% -200 mesh for the secondary grinding, the final iron concentrate grade 58.26% and having an iron recovery of 8.33% can be achieved after reverse flotation process test on magnetic concentrate.

Iron tailing is a kind of waste after extracting iron element. It caused a series of environmental problems. In this paper, it was used to make mineral polymer. After activation of it, the product compressive strength reached 70.46MPa when the dosage of iron tailing was 70%, sodium hydroxide 50% and the solid-liquid ratio was 0.4. This experimental study provides a good basis for the utilization of iron tailing.

Slump and compressive strength of the concrete with different steel slag powder content and different finenesses were discussed in this paper. It was indicated that: 1) High performance concrete with higher strength can be made using ground steel slag powder. 2) The greater content of steel slag powder, the more obvious was the effect of reducing slump losing. 3) About 40MPa concrete can be made using the steel slag powder whose specific surface was 510~600m2/kg under the condition that the content of steel slag powder was 50%~60%. 4) When the content of steel slag to be certain, the finenesses of steel slag powder had little effect on the performance of concrete.

By using fly ash as raw material to prepare thermal insulation material in this research. The relationship between the compressive strength and the influence factors was systematically discussed. The compressive strength of the samples reached max when the dosage of silica fume was 5%, sodium hydroxide 40%,the solid-liquid ratio was 0.75 and the content of foam was 4%. The experimental results provided a good basis for manufacturing the thermal insulation material and improving its property.

The tailings and slag based geopolymers was prepared by sodium silicate, sodium hydroxide alkali-activated tailings and slag. The compressive strength in 7 d under different raw material proportion were tested. The result indicated that tailings and slag based geopolymers has high compressive strength . As the tailings in slag is 80%, the compressive strength in 7d can reach 45.10 MPa . As the Na2SiO3 to NaOH ratio is 0.5, the compressive strength in 7d can reach 63.79 MPa. As the NaOH and sodium silicate concentration in the solution is 35%, the compressive strength in 7d can reach 38.35 MPa respectively; As the curing period is 14 d , the compressive strength can reach 71.25 MPa. As the steel scoria in solid is 20%, the compressive strength in 7d can reach 61.86 MPa respectively.