Advanced Materials Research Vols. 781-784

Abstract: The widely used technologies of Selective Catalytic Reduction (SCR), Non-selective Catalytic Reduction (SNCR) and hybrid SNCR-SCR for coal-fired boiler in China are reviewed. The technical characteristics of different processes and transformation methods are compared. Analysis is made about the advantages of each technology and the major problems in the retrofitting. The proposal for the corresponding problems is presented. Reference is provided for coal-fired boiler denitrification transformation in China.

Abstract: An energy model was developed based on the fuel-product concept. The matrix equation for exergy balance of regenerative system was established, and the mathematical model for exergy analysis of thermal system was structured. Exergy losses, exergy loss rate, exergy loss coefficient and exergy efficiency of the main components of a domestic N600-24.2/566/566 power plant were calculated based on this model. The results showed that the exergy efficiency of high pressure heaters are higher than that of low pressure heaters; the exergy efficiency of grade group of the intermediate pressure turbine are higher than the grade group of high pressure turbine and low pressure turbine. The exergy efficiency of the last grade group of low pressure turbine is the lowest. The exergy efficiency of the governing stage and the last grade group of low pressure turbine are 82.999% and 85.911%; the coefficient of exergy loss is maximum in the boiler (39.204%); the exergy effciency of superheater and reheater are 51.52% and 51.7%. Therefore, superheater and reheater have the largest energy conservation potential. Governing stage and low pressure turbine have more energy conservation potential.

Abstract: We set up information about Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/F) level in flue gas, ambient air, banyan leaves and soil nearby Muzha MSWI, located in the north of Taiwan. Total PCDD/F I-TEQ concentrations in flue gas are 0.0995, 0.0711ng I-TEQ/Nm3, respectively, in spring, autumn, all below the emission limit regulated by Taiwan EPA, 0.1ng I-TEQ/Nm3 . The mean PCDD/F concentrations in ambient air nearby Muzha MSWIs are 0.0283, 0.0357, 0.0391 and 0.05638pg I-TEQ/Nm3, respectively at four seasons. The mean PCDD/F concentrations in banyan leaves nearby are 3.86, 0.873ng I-TEQ/kg, respectively in spring, autumn. The mean PCDD/F concentrations in soil nearby are 1.733, 2.061ng I-TEQ/kg, respectively in spring, autumn, much lower than the emission limit in soil regulated by Taiwan EPA, 1000ng I-TEQ/kg. By comparing the PCDD/F concentration of sample at upwind and downwind sampling sites, the PCDD/F influence from Muzha MSWI on nearby ambient air, vegetation and soil is not obvious.

Abstract: High temperature CO₂ capture via a CaO-based sorbent was investigated in a fluidized bed. The sorbents tested included natural limestone, pellets made from powdered lime with a calcium aluminate cement binder, mixtures of natural limestone and alumina with a ratio of 1:1 and 2:1. Air-combustion flue gas with a composition of 15% CO₂ + 6% H₂O + 3% O₂ + 76% N₂ at 680°C and oxy-combustion flue gas with a composition of 80% CO₂ + 16% H₂O + 3% O₂ + 1% N₂ at 950°C were used as a carbonation and calcination atmosphere separately to simulate real CFB running conditions. Results showed that pellets have a lower carrying capacity (g CO₂/g calcined limestone or pellets) than nature limestone for the first few cycles mainly due to the existence of calcium aluminate cement (CaAl₂O₄) binder, while pellets have better cyclic activity than natural limestone. Solids agglomeration was found to be a big problem in the application of using Ca-based sorbent to capture CO₂. The solids was not powdery as original ones and tended to clump together after few cycles, making it difficult to fluidize and some dead areas form in the fluidized bed. Agglomeration became severer as cycle number increase and pellets had a much slighter agglomeration than nature limetone due to large particle size. The two mixtures were run in different conditions and H₂O was speculated to accelerate agglomeration.

Abstract: The petrochemical industry developed with huge energy consumption and industrial wastes discharge problems. This paper analysis and deals with these problems by using wastes comprehensive utilization model based on circular economy theory and provide suggestions on ways to improve the utilization efficiency of resources, energy and waste, give an optimization process designed as well as resource processing depth by empirical research.

Abstract: Applying gradual energy integration and optimization strategy, the energy utilization system of the air separation system utilizing LNG cryogenic energy is optimized. By analyzing the original process T-H diagram, reducing the pressure of N₂ compression cycle will be a more reasonable way to use the LNG cold energy, and decrease the system power consumption. Due to N₂ liquefaction temperature falling under the LNG gasification temperature when N₂ compression pressure is decreased from 4.0 MPa to 3.0 MPa, a new LNG cold energy utilization method is proposed. Firstly, LNG is throttled to 0.12 MPa, gasification, and then re-compressed to 0.3 MPa. By adjusting the amount of N₂ in compression cycle and LNG, hot and cold streams achieved a complete match. The heat transfer temperature difference is significantly reduced. Two basic parallel composite curves are constructed, and the energy is reasonable utilized. After improvement, the power consumption is reduced 44.6 kW, which prove this energy integration is effective.

Abstract: Fund is one of the key elements for Energy Industry to make a development aiming at low-carbon emission. This paper analyzes the connotation of low-carbon emission for Energy Industry and principles of financial support for the Energy Industry of low-carbon development, pointing out the short-coming of the current financial support for the development of China 's Energy Industry to achieve low carbon emission, and recommending the ways to enhance the current financial support such as financing, financial innovation, and cooperation of banking enterprises, etc.

Abstract: The paper elaborates development strategy of low-carbon economy in China on the basis of describing the relationship between low-carbon economy and industrial structure as well as industrial structure influencing factors, through analysis by China national conditions and the difficulties and obstacles encountered in the process of reducing carbon emissions.To some extent, it can provide theoretical support and practical guidance for industrial structural transformation which is based on the development of low-carbon.

Abstract: In view of the practical significance of the establishment of model database of slab heating, the dynamic forecasting model of temperature field in slab is established by the numerical solution according to the energy conservation in this paper. The ANSYS simulation has been successfully introduced to the modeling simulation of slab heating based on the character of slab heating. The simulation results emerge the temperature field and heat transfer of slab heating, and offer investigative instrument for the more analyse of slab heating and heating system. The temperature field in slab and energy saving would be achieved by using the model database of slab heating.

Abstract: This paper is based on STIRPAT model, combined with backcasting theory, using ridge regression analysis to analyze the related data of Tianjin from 1996 to 2011.This paper aims to explore the influences of the five driving factors on the carbon emissions in Tianjin, including population, affluent degrees, Energy intensity, Urbanization rate and the ratio of the tertiary industry. This paper is trying to make policy recommendations to change these influential factors, thus, to decrease the urban carbon degree.