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Abstract Many organizations in the world are interested in waste management problems and their potential solutions. In order to solve these problems, a Japanese venture company has developed an innovative thermal decomposer for organic wastes called ERCM (Earth-Resource-Ceramic-Machine). The ERCM reactor employs electron injected air to promote the thermal decomposition reaction, while the effect of electron injection into air has not yet been clarified. An experimental work was performed using a fixed bed reactor to explore the effects of different parameters of electron injection into air, the reaction temperature and different feedstock on the syngas generation. The main purpose of this study is to clarify the phenomena occurring in the ERCM reactor where a direct current electric field is produced in the flame reaction zone to enhance the thermal decomposition of wastes. In this regard, a mathematical model for simulating the thermal decomposition of solid waste in the presence of an electric field have been developed. The equations of aero-thermochemistry are coupled to the balance equations for densities of charged species, and the Poisson equation for the electrical potential is solved. The model was validated by the experimental data and showed a good agreement. The results showed that the electric field significantly improves the stabilization of the flame. From the release behavior of CO and CO2, it is noted that the electron injection would affect the char combustion process significantly. Finally the effect of the flame reaction zone generated by the field induced ion wind on the thermal decomposition was investigated.

AbstractBeijing-Tianjin area is one of the most important economic area in China, CO2 emission is also quite large corresponding to the positive economic date in the area. CCUS (Carbon Capture, Utilization and Storage) technology has been considered as one of solution for CO2 emission reduction. Dagang oilfield is in the area and belong to Bohai Bay Basin, most of CO2 sources in the area, such as power plants, steel factories, refineries are located on or closed to Dagang oil field, so Dagang oilfield has been selected as the CO2 sink.In the paper, the evaluation model has been firstly set up, combing with the different methods. Then, the characteristics of Dagang oil field and the sub-oil fields has been evaluated. As there are several sub-oil fields in Dagang oil field, the sub-oil fields’ data has been collected and analyzed, the properties of the crude oil, such as MMP, have also been tested, the EOR potential for different sub-oil fields has been calculated and compared. One of typical sub-oil fields has been selected for the CO2-EOR (CO2 Enhanced Oil Recovery) pilot test.Considering the, Bohai Bay basin's fault systems are complex development and belonging to the earthquake-prone, the risk assessment for CO2-EOR storage in Dagang oil field has also been done.

AbstractGlobal climate warming caused by emission of greenhouse gas including CO2 is one of serious problems nowadays. In an effort to mitigate CO2 emissions, one of most effectively clean energy plan is to produce power from coal using the integrated gasification combined cycle (IGCC). However, the cost of existing CO2 capture technologies is still too high. Utilization of large-solubility and low-cost absorbent for CO2 capture in IGCC can effectively reduce the electricity price increase caused by addition of CO2 removal unit. As it needs to trap CO2 before combustion under high pressure in IGCC absorption is considered to be a better choice.HPP (Hot Potash Process) uses aqueous solution of potassium carbonate as the absorbent. Compared to physical solvent absorption method Rectisol and Selexol, HPP has relatively low investment and relatively high CO2 recovery. Even in comparison with other chemical absorbent amine method HPP still has advantages as good chemical stability and low vapor pressure.In this paper several activators piperidine, piperozine, pyrazine, morpholine, imidazole, N-hydroxyethyl piperozine, Naminoethyl piperozine, AMP was tested respectively at 70 °C. As a result, piperidine activation works best, followed by N-(2-hydroxyethyl)piperazine, N-(2-aminoethyl) piperazine, 2-amino-2-methyl-1 -propanol and piperazine, pyrazine and imidazole is at its worst. Among them, N-(2-hydroxyethyl)piperazine is less volatile, more stable and suitable as the activator. Absorbing capacity and absorbing rate of CO2 in carbonate aqueous solution with HPZ increases by 5% or more than those with PZ.An improved HPP process is presented adopting the new activator. In this process two de-absorption two columns is designed operating at different pressure. This makes it possible to reuse the heat of condensation during high pressure de-sorption in reboiler of low pressure de-sorption. By preliminary calculating the novel process can save energy consumption obviously. The steam consumption, cooling water consumption and power consumption declines by 43.30%, 31.81% and 10.57%, respectively. It is expected to develop a low-cost technology for capture CO2 from IGCC in the future.

To reduce fine particulate matter emission from coal burning sources especially fossil fuel fired energy generation facility is critical to improve air quality. Attapulgite suspension was attempted to spray in a 6 kW fluidized bed facility and reduce fine particulate matter emission during coal combustion. The key parameters such as attapulgite mass, flowrate and spraying zone were investigated to determine the optimal and critical conditions that influence fine particulate matter emission. Exciting results indicate that both fine particle number and mass concentrations are largely decreased due to the physical/chemical absorption with the suitable mass ratio of 3 wt%. The spray of attapulgite suspension in both dense bed and dilute bed effectively mitigates fine particle emission based on the agglomeration and absorption. The most excellent result is achieved at a flowrate of 38 ml/min in dense bed with particle number reduction up to 93.5% in PM2.5 (fine particles is equal to/less than 2.5 μm), 93.6% in PM1.0 (fine particles is equal to/less than 1.0 μm) and 93.7% in PM0.1 (fine particles is equal to/less than 0.1 μm), respectively. The work highlights the potential of spraying attapulgite suspension as an effective process to reduce fine particle emission during coal combustion in fluidized bed system.

The blending of hydrogen gas into natural gas pipelines is an effective way of achieving the goal of carbon neutrality. Due to the large differences in the calorific values of natural gas from different sources, the calorific value of natural gas after mixing with hydrogen may not meet the quality requirements of natural gas, and the quality of natural gas entering long-distance natural gas and urban gas pipelines also has different requirements. Therefore, it is necessary to study the effect of multiple gas sources and different pipe network types on the differences in the calorific values of natural gas following hydrogen admixing. In this regard, this study aimed to determine the quality requirements and proportions of hydrogen-mixed gas in natural gas pipelines at home and abroad, and systematically determined the quality requirements for natural gas entering both long-distance natural gas and urban gas pipelines in combination with national standards. Taking the real calorific values of the gas supply cycle of seven atmospheric sources as an example, the calorific and Wobbe Index values for different hydrogen admixture ratios in a one-year cycle were calculated. The results showed that under the requirement of natural gas interchangeability, there were great differences in the proportions of natural gas mixed with hydrogen from different gas sources. When determining the proportion of hydrogen mixed with natural gas, both the factors of different gas sources and the factors of the gas supply cycle should be considered.

The new movement towards green chemistry and renewable feedstocks makes microbial production of chemicals more competitive. Among the numerous chemicals, organic acids are more attractive targets for process development efforts in the renewable-based biorefinery industry. However, most of the production costs in microbial processes are higher than that in chemical processes, among which over 60% are generated by separation processes. Therefore, the research of separation and purification processes is important for a promising biorefinery industry. This review highlights the progress of recovery processes in the separation and purification of organic acids, including their advantages and disadvantages, current situation, and future prospects in terms of recovery yields and industrial application.

The reduction of wet desulfurization wastewater is one of the important tasks of coal-fired power plants, and it is important for achieving "zero emissions." Evaporation and concentration (E&C) with waste heat is an effective way to reduce wastewater. Here, two typical types of industrial desulfurization wastewater are used to study the change rule of pH and total dissolved solids during wastewater concentration in a circulating evaporation tower. The results indicate that with the increase of concentration ratio, the pH of desulfurization wastewater is decreased rapidly and then is gradually stabilized at 2-3 when SO2 or SO3 is contained in flue gas, and the increase in conductivity is less for wastewater with higher SO42- content. The characteristics of various ions are also analyzed, and the composition and microscopic morphology of the precipitates are characterized during concentration. The growth pattern of Ca2+ concentration is dependent on the ratio of Ca2+ and SO42- in raw wastewater. When the concentration ratio is 7.21, the insoluble and slightly soluble substances undergo precipitation and the solid content is approximately 20%, which can help realize the concentration and reduction of desulfurization wastewater.

Biohydrogen (BioH2) is a low-carbon fuel with high energy efficiency. Although it can be produced using various technologies, the biological method has been deemed more sustainable and economically feasible. Extensive research has also led to identifying of lignocellulosic feedstocks (LCFs) as the highly abundant and renewable raw material for BioH2 production. Although there are many hurdles, the use of microbes-dependent processes for BioH2 production could bring down the operational cost and waste produced, and is efficient enough to meet future energy demands. In this review, the latest developments made in recent years regarding the biological conversion of LCFs to BioH2 are discussed. The microorganisms involved in the technologies of biological pretreatment, photo- and dark fermentation are presented. The recent developments made with genetic engineering and other factors (like pH, temperature, external additives, and nanomaterials) for enhancing the BioH2 production from microorganisms using the LCFs are discussed in detail. Each parameter has been explored and analysed to highlight its effects on maximizing hydrogen yield and enhancing the production rate. This aims to contribute to the ongoing research about the potential of these individual parameters to improve BioH2production. Furthermore, future perspectives on integration and improvement required to enhance the lignocellulosic-biohydrogen production process are also reviewed.