Process Modeling and Exergy Analysis for a Typical VOC Thermal Conversion Plant

The emission of volatile organic compounds (VOCs) represents a major source of air pollution and presents a major risk to both the surrounding environment and local health. An efficient and clean VOCs conversion process is an important approach for energy conservation and emission reduction. In this work, process simulation is conducted using Aspen Plus according to a VOC thermal oxidizing plant for an industrial-scale aluminum spraying production process. Experimental measurements are used for model validation and the pollutant emissions are consistent with the actual plant operating parameters, where the concentration of sulfur oxides is 32 mg/m³, and that of nitrogen oxides is ~34 mg/m³, both of which are below the requirements specified by the national environment regulations in China. Energy and exergy analyses have been conducted from the perspective of the second law of thermodynamics. It is found that 68.8% of the output energy in the system considered here enters the subsequent oven production line, which will be reused for drying the aluminum plates, and the rest of the energy will contribute to the water heat exchanger; however, the furnace features the largest exergy loss of 34%, and this is due to the high-temperature heat loss. The water heat exchanger features 11.5% exergy loss, which is the largest for the series of heat exchangers, and this loss is due to the large temperature difference between the hot and cold streams in the water heat exchanger. These findings are expected to provide practical approaches to energy conservation from the perspective of energy management

Modeling optimization for a typical VOCs thermal conversion process

Aiming at the current environmental problems, the thermal oxidation treatment for industrial VOCs emission is a common and effective measure. This paper studies on the optimization effect of one optimization method for direct VOCs thermal oxidation of a color aluminum spraying production line based on Aspen-Plus. According to the direct VOCs thermal oxidation process with a 30000 m³/h circulating air volume, propose the flue gas reflux and coating room drainage technology. Use the second law of thermodynamics, and the exergy flow analysis shows the methane consumption could be reduced 12%. Carbon emissions also decreased significantly, with 3.42% reduction. These findings are practical for industrial production cost saving and environmental protection problems solving

Modeling optimization for a typical VOCs thermal conversion process

Aiming at the current environmental problems, the thermal oxidation treatment for industrial VOCs emission is a common and effective measure. This paper studies on the optimization effect of one optimization method for direct VOCs thermal oxidation of a color aluminum spraying production line based on Aspen-Plus. According to the direct VOCs thermal oxidation process with a 30000 m³/h circulating air volume, propose the flue gas reflux and coating room drainage technology. Use the second law of thermodynamics, and the exergy flow analysis shows the methane consumption could be reduced 12%. Carbon emissions also decreased significantly, with 3.42% reduction. These findings are practical for industrial production cost saving and environmental protection problems solving

psi-Bufarenogin, a novel anti-tumor compound, suppresses liver cancer growth by inhibiting receptor tyrosine kinase-mediated signaling

Resistance of hepatocellular carcinoma (HCC) to existing chemotherapeutic agents largely contributes to the poor prognosis of patients, and discovery of novel anti-HCC drug is in an urgent need. Herein we report psi-Bufarenogin, a novel active compound that we isolated from the extract of toad skin, exhibited potent therapeutic effect in xenografted human hepatoma without notable side effects. In vitro, psi-Bufarenogin suppressed HCC cells proliferation through impeding cell cycle progression, and it facilitated cell apoptosis by downregulating Mcl-1 expression. Moreover,psi-Bufarenogin decreased the number of hepatoma stem cells through Sox2 depression and exhibited synergistic effect with conventional chemotherapeutics. Mechanistic study revealed that psi-Bufarenogin impaired the activation of MEK/ERK pathway, which is essential in the proliferation of hepatoma cells. psi-Bufarenogin notably suppressed PI3-K/Akt cascade, which was required in psi-Bufarenogin-mediated reduction of Mcl-1 and Sox2. psi-Bufarenogin inhibited the auto-phosphorylation and activation of epithelial growth factor receptor (EGFR) and hepatocyte growth factor receptor (c-Met), thereafter suppressed their primary downstream cascades Raf/MEK/ERK and PI3-K/Akt signaling. Taken together, psi-Bufarenogin suppressed HCC growth via inhibiting, at least partially, receptor tyrosine kinases-regulated signaling, suggesting that psi-Bufarenogin could be a novel lead compound for anti-HCC drug