Process exploration for scale melting and solidifying of municipal solid waste incineration (MSWI) fly ash by horizontal cyclone melting furnace.

This study used the horizontal tubular heating furnace to explore the melting potential of circulating fluidized bed (CFB) incinerator fly ash and mechanical grate furnace (MGF) incinerator fly ash. The horizontal cyclone melting furnace was then built to explore further the feasibility of scale melting of MSWI fly ash. The melting characteristic temperature, amorphous content, and heavy metal leaching concentration characterized the melting potential and solidification effect of MSWI fly ash.

Numerical simulation on the deposition characteristics of MSWI fly ash particles in a cyclone furnace.

In melting municipal solid waste incineration (MSWI) fly ash by cyclone furnace, the deposition characteristics of particles affect the slag flow and the secondary MSWI fly ash formation. In this study, the composition mechanism based on critical viscosity is selected as the particle deposition model to predict the deposition and rebound of particles on the furnace wall. The Riboud model with an accurate viscosity prediction performance is selected, then the particle deposition model is integrated into a commercial computational fluid dynamics (CFD) solver through the user-defined function (UDF) to realize the coupling of particle motion and deposition process.

Gasification reactivity of co-pyrolysis char from coal blended with corn stalks.

The gasification reactivity of coal and corn stalks co-pyrolyzed char is studied using thermogravimetric analysis, and the influence of co-pyrolysis on co-gasification reactivity is quantitatively characterized by synergy index. The results demonstrate that with increasing the pyrolysis temperature, the gasification reactivity of coal char gradually decreases, however, the gasification reactivity of CS char does not change monotonically. Furthermore, inhibition effect on co-gasification reactivity of 75% CS co-pyrolyzed char and se-pyrolyzed mixed char is shown at early stage of co-gasification and it gradually becomes synergistic effect as the co-gasification process progresses.

[Scale effect of Li-Xiang Railway construction impact on landscape pattern and its ecological risk].

As a large corridor project, plateau railway has multiple points and passes various sensitive environments along the railway. The determination of the scope of impact on ecological environment from railway construction is often controversial in ecological impact assessment work. Taking the Tangbu-Jiantang section of Li-Xiang Railway as study object, and using present land use map (1:10000) in 2012 and DEM as data sources, corridor cutting degree index ( CCI) and cumulative effect index of corridor (CCEI) were established by topology, buffer zone and landscape metrics methods.

Tungsten- and cobalt-dominated heavy metal contamination of mangrove sediments in Shenzhen, China.

A baseline investigation into heavy metal status in the mangrove sediments was conducted in Shenzhen, China where rapid urban development has caused severe environmental contamination. It is found that heavy metal contamination in this mangrove wetland is characterized by the dominant presence of tungsten and cobalt, which is markedly different from the neighboring Hong Kong and other parts of the world. The vertical variation pattern of these two metals along the sediment profile differed from other heavy metals, suggesting an increasing influx of tungsten and cobalt into the investigated mangrove habitat, as a result of uncontrolled discharge of industrial wastewater from factories that produce or use chemical compounds or alloys containing these two heavy metals.

Experimental and modeling study of the effects of multicomponent gas additives on selective non-catalytic reduction process.

The influence of multicomponent additives on NO reduction by selective non-catalytic reduction process has been investigated experimentally in an electricity-heated tube reactor. The multicomponent additives are composed of two species of CO, CH(4) and H(2), and the molar ratio of their two components varies from 1/3 to 3/1. The results show that all the investigated additives could decrease the optimal temperature for NO reduction effectively, but the contributions of their components are different.