Hanxiao Liu, Shuiyuan Luo, Lin Zhao, Yunjin Hu, Ying Cui, Jun Liang, Xiaowei Liu
{"title":"Comparative analysis of energy efficiency of electrostatic precipitator before and after ultralow emission in coal-fired power plants in China","authors":"Hanxiao Liu, Shuiyuan Luo, Lin Zhao, Yunjin Hu, Ying Cui, Jun Liang, Xiaowei Liu","doi":"10.1002/ghg.2216","DOIUrl":"10.1002/ghg.2216","url":null,"abstract":"<p>Electrostatic precipitator (ESP) is the main equipment for flue dust control of coal-fired power plants in China, accounting for about 70% of the total currently. In this paper, energy efficiency data of ESP, including 202 sets before ultra-low emission and 45 sets after ultra-low emission are systematically studied and analyzed by using the research method of field testing and technical investigation. The results showed that after ultra-low emission, the energy consumption and converted CO<sub>2</sub> emission of ESP in coal-fired power plants increased significantly, and the specific power consumption and energy consumption corresponding to unit mass particulate matter (PM) removal increased by 49.61% and 139%, respectively, and the converted CO<sub>2</sub> emission increased by 1.67 × 10<sup>−4</sup> kg CO<sub>2</sub>/m<sup>3</sup> and 31.12 kg CO<sub>2</sub>/t PM on average. The energy consumption of low-low-temperature ESP (LLT-ESP) was positively correlated with its emission reduction range. Before and after the gas cooler operation, the power consumption, specific power consumption and energy consumption corresponding to unit mass PM removal increased by 8.06%–38.68%, 10.66%–60.14% and 7.23%–62.98%, respectively, and the CO<sub>2</sub> emissions corresponded increased by 26.29–691.81 kg CO<sub>2</sub>/h, 0.46–2.18×10<sup>−4</sup> kg CO<sub>2</sub>/m<sup>3</sup>, 1.10–23.62 kg CO<sub>2</sub>/t PM, respectively. LLT-ESP had a great possibility to optimize the operation for energy-saving and carbon-reduction, because when the high voltage power supply operated on the maximum output mode and the energy-saving mode, the drop of power consumption and specific power consumption was around 52.00%–58.23%, 52.02%–58.29%, respectively, and the CO<sub>2</sub> emission reductions corresponded was 1,039.25–1,359.35 kg CO<sub>2</sub>/h, 2.71–3.58×10<sup>−4</sup> kg CO<sub>2</sub>/m<sup>3</sup>, respectively. LLT-ESP also had the great optimizing possibility for energy-saving and carbon-reduction during low load operation, as when the load reduced from 100% to 50%, the specific power consumption and energy consumption corresponding to unit mass PM removal increased by 5.05%–45.50%, 6.59%–63.90%, respectively, and the CO<sub>2</sub> emissions corresponded increased by 0.38–2.44×10<sup>−4</sup> kg CO<sub>2</sub>/m<sup>3</sup>, 6.76–45.98 kg CO<sub>2</sub>/h, respectively. The operation energy consumption can be effectively reduced by integrated use of multiple electric dust removal technologies, such as compared with LLT-ESP technology, the power consumption, specific power consumption and energy consumption corresponding to unit mass PM removal of “low-low-temperature + moving electrode+ electrostatic agglomeration” decreased by 37.88%, 30.08% and 45.29% respectively, and the corresponding CO<sub>2</sub> emission decreased by 697.22 kg CO<sub>2</sub>/h, 1.87×10<sup>−4</sup> kg CO<sub>2</sub>/m<sup>3</sup> and 32.98 kg CO<sub>2</sub>/t PM, respectively. ","PeriodicalId":12796,"journal":{"name":"Greenhouse Gases: Science and Technology","volume":"13 3","pages":"450-469"},"PeriodicalIF":2.2,"publicationDate":"2023-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42161066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Harshita Singh, Pankaj Singh, S. B. Agrawal, M. Agrawal
{"title":"Assessment of the Reverberations Caused by Predominant Air Pollutants on Urban Vegetation: A Multi-Site Study in Varanasi Located in Indo-Gangetic Plains","authors":"Harshita Singh, Pankaj Singh, S. B. Agrawal, M. Agrawal","doi":"10.3390/gases3020004","DOIUrl":"https://doi.org/10.3390/gases3020004","url":null,"abstract":"Plant responses to air pollution have been extensively studied in urban environments. Nevertheless, detailed and holistic studies assessing their retaliation to air contaminants are still limited. The present study evaluates the effect of criteria pollutants (SO2, NO2, PM10 and O3) on the overall biochemistry and resource allocation strategy of plants in order to categorize the dominant roadside species (Mangifera indica, Psidium guajava, Ficus religiosa, Azadirachta indica, Dalbergia sissoo, Cascabela thevetia and Bougainvillea spectabilis) of the Indo-Gangetic Plains (IGP), with different morphologies and habits, into species that are tolerant and sensitive to the prevailing air pollutants. This study was performed at three different land-use sites (industrial, commercial and reference) in Varanasi for two seasons (summer and winter). It was inferred that NO2 and PM10 consistently violated the air quality standards at all the sites. The fifteen assessed parameters reflected significant variations depending upon the site, season and plant species whereupon the enzymatic antioxidants (superoxide dismutase and catalase) and resource utilization parameters (leaf area and leaf dry matter content) were remarkably affected. Based on the studied parameters, it was entrenched that deciduous tree species with compound leaves (D. sissoo > A. indica) were identified as the less sensitive, followed by a shrub (C. thevetia > B. spectabilis), while evergreen species with simple leaves were the most sensitive. It was also substantiated that the morphology of the foliage contributed more toward the differential response of the plants to air pollutants than its habit.","PeriodicalId":12796,"journal":{"name":"Greenhouse Gases: Science and Technology","volume":"35 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2023-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75030382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}