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991.
农村户用沼气项目的碳减排效益核算——以湖北省恩施州为例 总被引:2,自引:0,他引:2
对现有的碳减排计算模型加以改进,对于关键参数的取值大部分参考我国学者的研究成果,以湖北省恩施州为例,从甲烷利用直接减排、化石能源替代减排、甲烷泄漏碳排放和甲烷燃烧碳排放4个方面,综合核算2000-2010年农村户用沼气项目的碳减排效益.结果表明,每口沼气池的碳减排量为1.10~1.29 t·a-1,碳减排量受沼气池规格(饲养生猪数量和类型)和地区气温变化等因素影响,每口沼气池的间接碳减排量(1.07 t·a-1)是直接碳减排量(0.22 t·a-1)的4.9倍.2000-2010年恩施州年碳减排效益整体随新建沼气池数量的增加而增加,碳减排量由2000年的3.97万t·a-1上升到2010年的70.93万t·a-1;2000-2010年恩施州户用沼气项目处理畜禽粪便导致的直接碳减排总量为157.44万t,沼气替代燃煤导致的间接碳减排总量为361.82万t,甲烷燃烧导致的碳排放量为13.12万t,甲烷泄漏导致的碳排放量为89.94万t,碳减排总效益为416.20万t. 相似文献
992.
Kamalesh J. Dube Lalit T. Ingale Sopan T. Ingle 《International journal of occupational safety and ergonomics》2013,19(4):551-560
Dust generated during the handling and processing of cotton causes ill health of ginning workers. The purpose of this study was to determine the prevalence of respiratory symptoms among cotton-ginning workers. This study involved 188 workers of 10 cotton-ginning factories. Forced vital capacity (FVC), peak expiratory flow rate (PEFR), and forced expiratory volume in 1 s (FEV1) declined significantly with increasing duration of exposure (p < .001) of the cotton-ginning workers. Results of a standard respirator medical evaluation questionnaire indicated that, depending on duration of exposure, 51%–71% of cotton-ginning workers suffered from chest tightness, 55%–62% experienced chest pain, while 33%–42% of the workers reported frequent cough. Blood tests of the workers showed higher values of erythrocyte sedimentation rate, eosinophils, and white blood cells when exposure was longer. Byssinosis symptoms were observed among the workers. We recommend regular periodical medical check-ups, compulsory use of personal protective equipment, and proper ventilation at the workplace. 相似文献
993.
Background. This study is concerned with household moving works and the characteristics of occupational injuries and sick leaves in each step of the moving process. Methods. Accident data for 392 occupational accidents were categorized by the moving processes in which the accidents occurred, and possible incidents and sick leaves were assessed for each moving process and hazard factor. Results. Accidents occurring during specific moving processes showed different characteristics depending on the type of accident and agency of accidents. The most critical form in the level of risk management was falls from a height in the ‘lifting by ladder truck’ process. Incidents ranked as a ‘High’ level of risk management were in the forms of slips, being struck by objects and musculoskeletal disorders in the ‘manual materials handling’ process. Also, falls in ‘loading/unloading’, being struck by objects during ‘lifting by ladder truck’ and driving accidents in the process of ‘transport’ were ranked ‘High’. Conclusion. The findings of this study can be used to develop more effective accident prevention policy reflecting different circumstances and conditions to reduce occupational accidents in household moving works. 相似文献
994.
Sławomir Zakrzewski Katarzyna Majchrzycka Agnieszka Brochocka Krzysztof Makowski 《International journal of occupational safety and ergonomics》2013,19(2):164-170
In most industrial enterprises, hazardous factors are present in quantities exceeding permissible levels. Such a situation requires using antidust respiratory protection. It has been suggested, however, that filters for respirators are not assessed properly and that lab results might not be related to real filtering efficiency in industry. This article contains test results of some commercially available filtering half-masks, including the effect of loading with real dust, high humidity, high temperature, and a combination of loading with dust and high humidity on the half-masks’ performance. The results show that the effect of these factors is considerable and that a combination of loading with silica dust and exposing to high humidity can cause a complete loss of performance. 相似文献
995.
The primary aim of the study was to analyse the non-steady state of filtration for selected electrostatic filter materials designed for use in respiratory protective devices. The obtained results showed that the filtration process in electrostatic filters was dependent in the main on the following factors: type of the filter material, electrostatic field strength of the material, and the charge of the aerosol.To a lesser degree the filtration process depended on the sign of the charge and the relative humidity of the air. A significant correlation was found between the increase in the penetration and the decrease in breathing resistance while the filter was being loaded.The effect of resuspension (tearing off and re-deposition of dust agglomerates inside the filter) on the filtration process very significant. It was also observed that under certain conditions electrostatic filter materials lost their protection properties. 相似文献
996.
Tirthankar Ghosh Sangita Barman 《International journal of occupational safety and ergonomics》2013,19(1):91-96
This study was undertaken to assess the pulmonary and respiratory problems of workers in a zarda factory. A total of 70 permanent zarda workers (50 manufacturing workers and 20 office ones) were studied in a factory in Baguihati, Kolkata, India. The study included (a) completion of a questionnaire (on pulmonary and respiratory problems), (b) measurement of physical parameters, (c) spirometry and (d) measurement of peak expiratory flow rate. At the same time, the worksite was analyzed with an OSHA-recommended ergonomics checklist. Many zarda manufacturing workers complained of respiratory symptoms. Continuous exposure to the tobacco processing environment reduced the workers’ lung volume and peak expiratory flow rates. Our study indicates that zarda manufacturing workers may have respiratory and pulmonary disorders related to exposure to tobacco dust in their work environment. 相似文献
997.
本文介绍了大型吹砂吹尘综合试验系统的设备构成和系统设计应考虑的关键技术。阐述了主要功能和技术指标,论述了砂尘浓度、试验段风速、试验段温度和相对湿度等主要试验参数的调节技术,并给出了应用结果。能够为大型吹砂环境试验设备的设计和试验应用提供参考借鉴。 相似文献
998.
中国石油宁夏石化公司采用循环喷淋洗涤技术回收尿素造粒塔粉尘,在该回收系统的运行过程中,存在排气中尿素粉尘含量偏高的情况,从设备管理和工艺优化等方面查找原因,制定应对措施并逐一进行实施,从而降低造粒塔排气中尿素粉尘的含量,减少空气污染,达到了污染减排的目的。 相似文献
999.
1000.
脉冲清灰系统是袋式除尘器和电袋除尘器的关键技术之一。通过理论估算的方法确定系统关键参数的初值,并依靠在脉冲喷吹试验平台试验的方法来获得最优的设计参数。 相似文献