Study on Mechanical and Microscopic Properties of Nickel–Copper-Contaminated Soil Solidified by Cement, Fly Ash and Desulfurization Gypsum Under Carbonization Condition

The engineering characteristics of remediated soil are easily affected by CO2 erosion in nature. However, there are limited investigations on the mechanical and microscopic properties of heavy metal-contaminated soil. This study introduces effect of accelerated carbonization on the mechanical and microscopic properties of nickel–copper-contaminated soil, and the soil has been treated with a novel curing agent, formed by mixing cement, fly ash and desulfurization gypsum (CFG). The objective of the study is to ascertain CO2 erosion resistance of nickel–copper-contaminated soil solidified by CFG. Using unconfined compressive strength (UCS) tests, carbonization depth, X-ray diffraction, and scanning electron microscopy, the sample’s characteristics are investigated under different carbonization times and heavy metal ion concentrations. The results demonstrate that the UCS of samples of Ni0Cu0, Ni0.02, and Ni0.4 decrease with the increasing carbonization time, while that of Ni1, Cu1, and Ni1Cu1 increase initially and then decrease; in addition, when the concentration of heavy metals is lower, the effect of carbonization on UCS of samples is more significant. Moreover, the carbonization depth of samples increases with the increasing carbonization time, and the prediction model is given. Furthermore, the microscopic analysis demonstrates that calcium carbonate is the main carbonization product. The decomposition of hydrated calcium silicate gel leads to poor integrity of the structure and more pores produced in samples, which is the main reason for the decrease of the UCS in the process of carbonization. The outcomes of this investigation provide a reference for the durability in practical engineering of heavy metal-contaminated soil solidified by CFG.

Study on the Technology Co-Carbonization for Biomass and Coal

This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. Iodine adsorption method is used as a valuation means, the study was carried out on the co-carbonization of coal and biomass by the analysis of Iodine adsorption value. The research results show that the straw and cow dung has important effects on carbonization process; According to change rule of the Ignition loss rate and the iodine adsorption value, the iodine adsorption value of straw-coal co-carbonization product is higher than cow dung; Dashing treatment has significant effects on the iodine adsorption value carbonized product; the catalytic carbonization Biomass is the result of KOH effecting.

Oxidation Resistant of Silicon-Boron Pitch Carbonization Product

The silicon-boron(Si-B) pitch was successfully synthesized by solution-thermal treatment method using coal pitch, polycarbosilane and borane pyridine as starting materials. The B-Si pitch carbonization product was attained by carbonization in the temperature 900°C under flowing argon. The Si-B pitch prepared and its carbonization product were characterized by SEM, FT-IR, TG-DSC and XRD. The results show that the carbonization product has C-Si and C-B bonds and the silicon and boron components of the product is still amorphous when it is treated at 900°C. The weight loss of the Si-B pitch carbonization product at 900°C for 12h in air atmosphere is only 3.76wt%. The weight loss of the product is less than 4 wt% when the oxidation temperature reaches 1180°C. The prepared B-Si pitch carbonization product possesses good anti-oxidation property at high temperature in air atmosphere.

Effects of a carbonization product as additive on the germination, growth and yield parameters of agricultural crops

The effects of the carbonization product of separated communal waste as an additive to the soil was studied on the germination, quantitative growth and yield parameters of maize (Zea mays L.), bean (Phaseolus vulgaris L.) and tomato (Solanum lycopersicum L.). The product was tested on three soil types with different humus content and mineral composition in doses of 1, 10 and 20 g of additive per kg soil, with application before seeding or after plant emergence, under greenhouse and field conditions. It was found that plants utilized the nutrient content from the carbonization products in both methods of application and that the stimulatory effect on the germination, fresh and dry mass and yield parameters of the treated plants was dependent on the plant species, soil type, dose and method of application. A significant effect of the additive was found on the germination of bean, which increased by 8-22% over the control. Fresh and dry mass increased by 18-62% in maize and by 2-30% in bean when the additive was applied under greenhouse conditions. In the field the additive was found to have a positive effect on the average mass of tomato fruits and maize cobs, and on the yield per plant.