Fine particles removal of pyrolysis gasification flue gas from rural domestic waste: Laboratory research, molecular dynamics simulation, and applications.

Article

作者: Liu, Zhenkun ; Cheng, Teng ; Wei, Di ; Zhang, Yumeng ; Wang, Bo ; Lv, Pengfei

Chinese rural domestic waste has increased considerably with the modernization of agriculture and urbanization. Pyrolysis gasification is a common high-temperature waste treatment method. However, this method is usually accompanied by a large amount of particle emission. In this study, a rural domestic waste pyrolysis gasification station in Gansu Province, Northwest China, was selected for research. The particle emission characteristics of this station were analyzed, and the results showed that the original particle removal technologies were inefficient in fine particles. Hence, a new method of fine particle treatment, i.e., Cloud-Air-Purifying (CAP) technology, was explored herein. In CAP, fine particles grow in size via heterogeneous condensation in a supersaturated water vapor environment and are then collected efficiently using a supergravity field. A laboratory-scale pyrolysis gasifier and CAP equipment were built. Moreover, the CAP removal efficiency for particles generated from four typical rural domestic waste categories was studied. The results showed that CAP technology considerably increased the efficiency of fine particle removal. However, the removal efficiency for particles released owing to the incineration of wood was only ∼75%. This was because the tar substances formed during wood pyrolysis were attached to the surface of escaping particles, which led to a decrease in their hydrophilicity and particle condensation growth. To address this issue, the improvement in particle hydrophilicity using different surfactants was studied via molecular dynamic simulations. When the increase in water molecule adsorption, surface polarity, and the solid-liquid interaction energy for different surfactants were compared, alkylphenol ethoxylate (OP10) proved to be the most effective surfactant. Finally, the improved CAP technology combined with OP10 was applied to the on-site pyrolysis gasification flue gas treatment. Long term monitoring of the proposed technology revealed that particle removal efficiency remained >94%, exhibiting excellent fine particle removal. The successful application of the proposed technology demonstrates its potential for further application.

2023-10-24·ACS omega

Wettability Characteristics of Low-Rank Coals Under the Coupling Effect of High Mineralization and Surfactants.

Article

作者: Meng, Xiangfei ; Liu, Hongyong ; Li, Zhen ; Wang, Yushan ; Zheng, Chunshan ; Song, Fei

This paper investigates the unclear influence mechanism of the surfactant effect on improving coal seam wettability and CO₂-enhanced coalbed methane technology to enhance the gas extraction efficiency in some coal mines under highly mineralized environments in China. Specifically, the microinfluence mechanism of the coupling effect of nonionic surfactant OP-10 and highly mineralized coal samples under special treatment on the wettability of coal seam is examined. By measuring the contact angle and surface tension of the samples, it is confirmed that high mineralization can limit the effect of surfactants on improving the wettability of coal seams to a certain point. Infrared spectroscopy and X-ray diffraction measurements were conducted on the samples under coupling conditions. It is found that high mineralization impedes the effectiveness of surfactants in enhancing the wettability of coal seams. The surfactants interact with coal samples at the functional group level, producing new hydrophilic functional groups and increasing the content of kaolin with strong hydrophilic properties, thereby increasing the wettability of coal seams. However, these hydrophilic functional groups disappear under coupling conditions and hydrophobic functional groups are produced. Additionally, high mineralization inhibits the effect of surfactants on the phase composition of coal samples. The findings of this research provide a theoretical basis for water injection of highly mineralized coal seams and methane replacement recovery by carbon dioxide technology, promoting the practical application of water injection and gas injection displacement of coal seams.

2023-10-06·Molecules (Basel, Switzerland)

Effects of Hydrogen Bonds between Ethoxylated Alcohols and Sodium Oleate on Collecting Performance in Flotation of Quartz.

Article

作者: Zhang, Na ; Sun, Chunbao ; Kou, Jue ; Li, Jiajia

Hydrogen bonds play an important role in the interaction between surfactants. In this study, the effect of three different ethoxylated alcohols (OP-10, NP-10, AEO-9) on the collecting behavior of sodium oleate (NaOL) in the flotation of quartz was investigated. To explore the mechanism, the hydrogen bond between ethoxylated alcohols and NaOL was analyzed using molecular dynamics (MD) simulation. The results showed that ethoxylated alcohols promoted the collecting performance of NaOL and reduced the dosage of the activator CaO and the collector NaOL in the flotation of quartz. The Zeta potential measurement illustrated that ethoxylated alcohols promoted the adsorption of OL^- on the activated quartz surface and the degree of promotion was in the order of OP-10 > NP-10 > AEO-9. The MD simulation results showed that a hydrogen bond presented between ethoxylated alcohols and OL^-. Due to the hydrogen bond between the ethoxylated alcohols and OL^-, the attraction force between OL^- and the quartz surface increased with the addition of ethoxylated alcohols in the order of OP-10 > NP-10 > AEO-9 based on the MD simulation results. As the result, the addition of ethoxylated alcohols increased the adsorption density of OL^- on the activated quartz surface, which explained the promotion of the collecting performance of OL^- in the flotation of quartz.

100 项与 OP-010 相关的药物交易

登录后查看更多信息