Emission Reduction Process Research Articles

Driving determinants and prospective prediction simulations on carbon emissions peak for China’s heavy chemical industry

Abstract Unprecedented huge mitigation task should be associated with profound efforts in facilitating emission reduction process over the globe. As the largest CO2 emitting country, China has been strenuously promoting the mitigation resilient development pathways in conjunction with the 2030 carbon emission peak commitment from Nationally Determined Contribution document which submitted under the Paris Agreement. Based on the peaking objective, carbon emission in heavy chemical industry should be received most attentions in terms of its large proportion with respect to the emission sources from other sectors. Particle swarm optimization (PSO) algorithm optimized back propagation neural network (BP) model is employed to predict future carbon emission for heavy chemical industry with the timeframe of 2017–2035 on the basis of the previous data. The significant magnitude of each carbon emission driving force is acquired in terms of the absolute influence coefficient method. The results indicated that, carbon emission in heavy chemical industry and its corresponding sub-sectors could be achieved peak under the implementation of the predetermined mitigation scenarios. The proportion of carbon emission in energy processing industry, steel industry, and building material industry is accounted for a larger fraction over the cumulative carbon emission in heavy chemical industry during the simulation period upon 2035.

Carbon audit evaluation system and its application in the iron and steel enterprises in China

China launched its carbon emissions trading market and established a national carbon emissions trading system in 2017, both of which call for accurate carbon audits to reflect carbon emissions of enterprises. Drawing on the carbon audit theory and the driving force-state-response (DSR) model, this paper aims to construct a carbon audit evaluation index system and to analyse the application of the system in the iron and steel enterprises in China. Data was collected from the Statistical Yearbook and the Sustainable Development Report and Financial Report of the iron and steel enterprises in China from 2011 to 2015. Research results show that establishing a carbon audit evaluation index system plays an essential role in implementing carbon audits; the system also improves the corporate carbon auditing system and evaluation mechanism, optimises the enterprise’s energy saving and emission reduction process, and makes a positive contribution to a low-carbon economy. The research also identifies several issues in relation to carbon audits in the iron and steel enterprises, including insufficient infrastructure and the shortage of talents for carbon audits, and the lack of innovation in clean production technology and capital investment.

Dynamics of spray impingement wall film under cold start conditions

Fuel film that adhered on engine walls from spray impingement is considered a primary source of harmful combustion emissions. However, the physics of the wall film formation, propagation, and breakup is not fully understood yet because of its multiphase nature. Existing literature has revealed that the mass transportation within the fuel film takes a wave propagation form. This article aims to identify the dynamics of the wall film during spray impingement via high-speed laser diagnostics. In this work, a single-hole injector was used and the spray impinged onto a stage made of sapphire glass for diagnostics purposes. Iso-octane was used as the fuel and 10% ethanol was blended to dope rhodamine 6G as the fluorescent species for laser excitation. Simultaneous optical measurements, such as laser-induced fluorescence and Mie scattering, are performed to obtain the characteristics of the wall film quantitatively. Various aspects of the wall film, including the frequency of the wave, wave speed, and wave height, are inspected. The impact of fuel temperature and wall temperature under typical cold-start conditions are also studied to investigate the temperature dependence of the wall film dynamics. The research is also intended to provide quantitative experimental data for numerical models for impingement prediction and thus help the process of emission reduction and combustion optimization of internal combustion engines.

Recent Development of Energy-saving Technologies in Ironmaking Industry

Environmental protection and carbon emission reduction pressures are increasingly becoming a key factor affecting the sustainability of China’s steel companies at this stage. The key to energy saving and emission reduction in the steel industry lies in the innovation of ironmaking technology. It is inevitable to innovate and improve the traditional blast furnace ironmaking process and further strengthen the development of new ironmaking processes. This paper briefly reviews the representative achievements of iron and steel energy saving and emission reduction and new ironmaking process development in recent years, such as blast furnace utilization of alternative fuel, oxygen blast furnace ironmaking process, HIsarna smelting reduction ironmaking technology, COURSE50 technology and RHF iron nugget technology. It is expected to provide reference for achievement of energy saving, emission reduction and sustainable development of China’s steel industry.

Which provinces should pay more attention to CO2 emissions? Using the quantile regression to investigate China's manufacturing industry

At present, China's carbon dioxide (CO2) emissions ranked first in the world. Moreover, the manufacturing industry is the biggest contributor to CO2 emissions. Most of the existing studies use the average estimation method to investigate the main drivers of CO2 emissions in this industry. However, the data distribution of economic variables is often not normal distribution, and the tail of the data hidden important information. In order to provide a realistic basis for emission reduction in this industry, this paper applies the quantile regression approach to investigate the driving forces of CO2 emissions under high, medium and low emission levels. The empirical results indicate that the effect of economic growth on CO2 emissions in the upper 90th and 75th–90th quantile provinces are higher than those in the other quantile provinces. The influence of energy intensity in the 25th–50th quantile provinces is lower than those in the other percentile provinces. The impact of urbanization in the upper 90th quantile provinces is the strongest in all the quantile provinces. However, the influence intensity of energy structure in the lower 10th quantile provinces is the highest in all the quantile provinces. Therefore, policymakers should focus on the heterogeneous effects of driving forces on CO2 emissions in different quantiles during the process of CO2 emission reduction.

Experimental investigation of N2O formation in selective non-catalytic NOx reduction processes performed in stoker boiler

Abstract Stoker fired boiler plants are common throughout Eastern Europe. Increasingly strict emission standards will require application of secondary NOx abatement systems on such boilers. Yet operation of such systems, in addition to reducing NOx emissions, may also lead to emission of undesirable substances, for example N2O. This paper presents results of experimental tests concerning N2O formation in the selective non-catalytic NOx emission reduction process (SNCR) in a stoker boiler (WR 25 type). Obtained results lead to an unambiguous conclusion that there is a dependency between the NOx and N2O concentrations in the exhaust gas when SNCR process is carried out in a coal-fired stoker boiler. Fulfilling new emission standards in the analysed equipment will require 40–50% reduction of NOx concentration. It should be expected that in such a case the N2O emission will be approximately 55–60 mg/m3, with the NOx to N2O conversion factor of about 40%.

Energy efficiency of China's industry sector: An adjusted network DEA (data envelopment analysis)-based decomposition analysis

The process of energy conservation and emission reduction in China requires the specific and accurate evaluation of the energy efficiency of the industry sector because this sector accounts for 70 percent of China's total energy consumption. Previous studies have used a “black box” DEA (data envelopment analysis) model to obtain the energy efficiency without considering the inner structure of the industry sector. However, differences in the properties of energy utilization (final consumption or intermediate conversion) in different industry departments may lead to bias in energy efficiency measures under such “black box” evaluation structures. Using the network DEA model and efficiency decomposition technique, this study proposes an adjusted energy efficiency evaluation model that can characterize the inner structure and associated energy utilization properties of the industry sector so as to avoid evaluation bias. By separating the energy-producing department and energy-consuming department, this adjusted evaluation model was then applied to evaluate the energy efficiency of China's provincial industry sector.

Contribution of Cloud Computing in the Reduction of Carbon Dioxide Emission

The Information Technology industry is rapidly expanding and as a result its contribution to carbon dioxide emission is also rapidly increasing. Fortunately, the cloud computing industry is perceived by many to be a viable solution for reducing carbon dioxide emissions. Accordingly, there are numerous studies which try to prove that cloud computing can reduce carbon dioxide emissions up to more than half of the current carbon dioxide emissions. In this paper, two of such studies where reviewed to assess whether cloud computing is indeed a viable candidate for limiting and reducing the amount of carbon dioxide emitted by the IT industry. All the information gathered in this paper prove that; cloud computing is a promising technology which could reduce carbon dioxide emissions. The percentage of decrease can range from 10% to 90%. The effectiveness of the carbon dioxide emission reduction process is highly dependent on the size of the business organization. Accordingly the size of the organization is negatively correlated to the efficiency of carbon dioxide reduction. This means that as the size of the organization increase, carbon dioxide emission reduction decrease. This paper also presented the four reasons why cloud computing can reduce carbon dioxide emissions, which are: dynamic provisioning, multi-tenancy, server utilization, and data center efficiency.

Spatiotemporal Variability of Carbon Flux from Different Land Use and Land Cover Changes: A Case Study in Hubei Province, China

Carbon sources and sinks as a result of land use and land cover changes (LUCC) are significant for global climate change. This paper aims to identify and analyze the temporal and spatial changes of land use-based carbon emission in the Hubei Province in China. We use a carbon emission coefficient to calculate carbon emissions in different land use patterns in Hubei Province from 1998 to 2009. The results indicate that regional land use is facing tremendous pressure from rapid carbon emission growth. Source:sink ratios and average carbon emission intensity values of urban land are increasing, while slow-growing carbon sinks fail to offset the rapidly expanding carbon sources. Overall, urban land carbon emissions have a strong correlation with the total carbon emissions, and will continue to increase in the future mainly due to the surge of industrialization and urbanization. Furthermore, carbon emission in regions with more developed industrial structures is much higher than in regions with less advanced industrial structures. Lastly, carbon emission per unit of GDP has declined since 2004, indicating that a series of reform measures i.e., economic growth mode transformation and land-use structure optimization, has initiated the process of carbon emission reduction.

Regional Economic Growth and Carbon Emissions - A Case Study of Anhui Province

This essay tends to probe into the decoupling relationship between economic growth and carbon emissions through structuring the decoupling analysis model. The results show that: In recent years, the decoupling relationship between economic growth and carbon emissions in Anhui province has improved. Through the research about some intermediate variables, we find that the change trend of energy consumption elastic elasticity of carbon emissions and the one of GDP elastic elasticity of carbon emissions are basically the same. Meanwhile, Anhui province is relatively backward in the energy-saving and emission reduction process, carbon emissions growth and energy consumption growth did not achieve effective decoupling, which reflects that this province still has some defects in the adjustment of energy structure, energy saving and emission reduction technology promotion policy etc.

Governing shipping externalities: Baltic ports in the process of SOx emission reduction

This paper analyses the debate which has unfolded in the Baltic Sea Region regarding the reduction of sulphur content in vessel fuels, in order to illustrate how tightening environmental regulation challenges traditional forms of maritime governance. Using an interactive governance approach, this study reconstructs the process of sulphur emission reduction as a complex multi-stakeholder interaction in multiple contexts. The empirical investigation has drawn on documentary material from around the Baltic region, including Russia, and has applied the method of qualitative content analysis. The empirical study focuses on two interlinked questions: (1) How sulphur emission reduction policies are being anticipated by maritime industry, in particular by Baltic ports and (2) How port adaptation strategies are tied into Baltic local and energy contexts. Addressing these questions highlights the role of polycentricity in shipping governance and explains how the same universal international regulations can produce varying patterns of governance. The paper concludes that policy-making shall take an account of the fact that the globalized shipping industry is nevertheless locally and sectorally embedded.

A Game Pattern Analysis of the Cooperation and Competition of Global Carbon Emission Reduction

As a huge systematic project, low-carbon emission reduction involves all of the world's vital profit. From the perspective of cooperation and competition, the dynamic equilibrium process is analyzed around the low-carbon emission reduction game background in this paper. Focus on the relevant principles of game theory to give a global analysis to global carbon emission reduction market and to explain the phenomenon during the global carbon emission reduction process. Try to expose the planning and motivation of the various interest game groups.

Development of a process for producing high‐purity calcium carbonate (CaCO3) from waste cement using pressurized CO2

AbstractA new type of process for producing high‐purity calcium carbonate from waste cement powder was developed. The process consists of two main reactions; extraction of calcium in the form of calcium ions from waste cement powder in a water slurry by pressurized CO2 (typically at several MPa), and precipitation of calcium carbonate (CaCO3) from the extracted solution by reduction of the CO2 pressure. The process can be recognized as the emission reduction process of CO2 as well. Laboratory‐scale experimental studies were conducted for both the extraction reaction and the precipitation reaction, to examine the feasibility of the process. The extraction process was found to proceed at a relatively high rate, especially during the initial 10 min. The concentration of calcium ions exceeded the thermodynamic solubility of CaCO3 (supersaturation) when abundant waste cement was available. After filtration of the residues, CaCO3 particles with >98% purity were obtained by depressurizing the CO2. The dependency of the reaction rates on the operating conditions, such as the ratio of waste cement to water, CO2 pressure, and particle size of waste cement particles, was investigated. A process design was carried out based on the experimental results, assuming that the present process is applied to two types of CaCO3 production process: flue gas desulfurization and production of ultrahigh‐purity CaCO3. The estimated costs per 1 metric ton of CaCO3 were USD 136 for desulfurization and USD 323 for high‐purity CaCO3. © 2005 American Institute of Chemical Engineers Environ Prog, 2005