纯镁铁水脱硫粘渣剂使用与改进

武钢第一炼钢厂将镁基喷粉铁水脱硫站改造成纯镁铁水脱硫工艺后因为脱硫后的渣少并且稀 ,不容易扒出 ,容易在转炉产生回硫。介绍了使用与改进粘渣剂 ,减少转炉回硫量的情况。

Influence of Polymer Binder on the Physical Properties and Stability of Engineering Spoil on a Slope

An experiment was performed to study the influence of polymer binders on the physical properties,and stability against a simulated rainfall,of a slope consisting of engineering spoil.Results showed that low polymer binder concentrations(≤500g/m3) could enhance the air permeability and moisture-retaining capacity of the engineering spoil;however,adding more polymer binder made the hardness of the engineering spoil increase and then decline.With the increase of polymer binder concentrations,the surface(0-5cm) permeability of the engineering spoil decreased but the permeability of the lower layers(5-10cm) increased.Polymer binders might reduce runoff and sediment,but the effect becomes weaker with the increase of rainfall.The results of this study have significance for engineering practices.Further experiments are needed to study the effects of binders under other conditions,such as natural rainfall,different slopes,different rock types,different degrees and spoil weathering and different added material,and the chemical interaction between soil and polymer binders.

TiO_2 nanoparticles' effects on properties of concrete using ground granulated blast furnace slag as binder

In the present study, compressive strength, pore structure, thermal behavior and microstrncture characteristics of concrete containing ground granulated blast furnace slag and TiO2 nanoparticles as binder were investigated. Portland cement was replaced by different amounts of ground granulated blast furnace slag and the properties of concrete specimens were investigated. Al- though it negatively impacts the properties of concrete at early ages, ground granulated blast furnace slag up to 45 wt% was found to improve the physical and mechanical properties of concrete at later ages. TiO2 nanoparticles with the average particle size of 15 nm were partially added to concrete with the optimum content of ground granulated blast furnace slag and physical and mechanical properties of the specimens were measured. TiO2 nanoparticle as a partial replacement of cement up to 3 wt% could accelerate C-S-H gel formation as a result of increased crystalline Ca（OH）2 amount at the early age of hydration and hence increase compressive strength of concrete. The increased TiO2 nanoparticles＇ content of more than 3 wt% may cause reduced compressive strength because of the decreased crystalline Ca（OH）2 content required for C-S-H gel formation and unsuitable dispersed nanoparticles in the concrete matrix. TiO2 nanoparticles could improve the pore structure of concrete and shift the distributed pores to harmless and less-harm pores.

Rheology and microstructure effects of waste spent coffee grounds in modifying asphalt binder

Herein the biowaste by-product spent coffee grounds(SCGs)from coffee industry were incorporated into asphalt binders for performance enhancement.From the analysis of Fourier transform infrared spectroscopy(FTIR),differential scanning calorimetry(DSC),dynamic shear rheometer(DSR),and Brookfield viscosity rheometer,it is confirmed that SCGs have potential prospects as bio-waste modifiers in the application of sustainable pavements.Results demonstrated that the modification process was mainly based on physical reinforcement.Compared with that of the neat asphalt,the shearing stress-resistant ability and high-temperature performance of the SCGs modified binders with the appropriate addition presented a bit of improvement;whereas the binders with 1%and 3%SCGs exhibited remarkably enhanced low-temperature stability.However,notable weaknesses of practical performance were shown for the binder with excessive content of SCGs,indicating the necessity of proportion selecting before application.