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To further optimize the polyacrylamide (PAM) dosage for the removal of gas sludge in scruhbing water from blast furnace gas scrubbing, the flocculative sedimentation is simulated in a dynamic manner with an agitating dcvicc on the principle of similitude. The effect of the size of the PAM dosage on the magnitude of the agglomerate of the gas sludge is explained 根据相似原理,用搅拌装置动态地模拟了现场高炉煤气洗涤水中瓦斯泥的絮凝沉降,以较准确地选择PAM的最佳投量。并说明了PAM投加量对瓦斯泥絮团大小的影响。 Continuous measurements of the methane flux from rice fields were carried out by using chamber technique . The results show that the methane flux from rice fields has a strong diurnal variation , and that the day-mean flux has a large seasonal variation . Based on the experiments, we estimate that the total emission of methane from rice fields in China is (17 ± 2) t/yr. Methane leakage from biogas pits is very little on the whole, with a range of 61 - 490 mg/hr/pit. The total emission from biogas pits in China... Continuous measurements of the methane flux from rice fields were carried out by using chamber technique . The results show that the methane flux from rice fields has a strong diurnal variation , and that the day-mean flux has a large seasonal variation . Based on the experiments, we estimate that the total emission of methane from rice fields in China is (17 ± 2) t/yr. Methane leakage from biogas pits is very little on the whole, with a range of 61 - 490 mg/hr/pit. The total emission from biogas pits in China may be of the order of 0.01 t/yr. Total emissions of methane from cattle in China are estimated to be 5.5 t/yr . Coal and oil mining may emit 6 t methane per year. Emissions from natural wetland in China are estimated to be about 2 t/yr . There is an important source of methane in China that has not been measured . Agricultural waste in China is often treated in cesspools, which are similar to the biogas pits . However, no methane is recovered from such cesspools . We estimate that the total flux of methane from such sources may be of the order of 5 t/yr. The total emissions of methane from sources in China are estimated to be about 35 ± 5 t/yr. 1987—1989年用自动连续采样分析设备对杭州地区的稻田CH_4排放进行了三年连续观测,1988—1990年用定期采样、分析方法对四川乐山地区的稻田CH_4排放进行了三年观测.发现稻田CH_4排放率有很大的日变化、季节变化和年际变化,这些变化主要是由土壤特性、水稻生长状况以及气象条件的变化造成的.不同地区稻田CH_4排放率差别很大,变化规律也不同,这种差别主要是由土壤特性,水稻品种及气候条件的差别造成的.根据现有观测资料,估计中国稻田CH_4年排放总量为17×10~(12)g.对沼气池的CH_4泄漏进行了三年系统观测研究,发现沼气池泄漏变化范围很大,但泄漏量总起来都很小,中国1000万个沼气池不构成大气CH_4的重要源.根据沼气池的泄漏估计了农村堆肥的CH_4排放量为3.2×10~(12)g/a;根据城市、稻田附近和沙漠地区大气CH_4浓度的测量结果推算了城市CH_4排放量;根据反刍动物消耗食物总量估计了反刍家畜的CH_4排放量;根据瓦斯排放资料估计了煤矿CH_4排放量;根据文献资料估计了中国天然湿地的CH_4排放量.最后估计了中国各种源的CH_4排放总量及未来变化趋势.1988年中国CH_4排... 1987—1989年用自动连续采样分析设备对杭州地区的稻田CH_4排放进行了三年连续观测,1988—1990年用定期采样、分析方法对四川乐山地区的稻田CH_4排放进行了三年观测.发现稻田CH_4排放率有很大的日变化、季节变化和年际变化,这些变化主要是由土壤特性、水稻生长状况以及气象条件的变化造成的.不同地区稻田CH_4排放率差别很大,变化规律也不同,这种差别主要是由土壤特性,水稻品种及气候条件的差别造成的.根据现有观测资料,估计中国稻田CH_4年排放总量为17×10~(12)g.对沼气池的CH_4泄漏进行了三年系统观测研究,发现沼气池泄漏变化范围很大,但泄漏量总起来都很小,中国1000万个沼气池不构成大气CH_4的重要源.根据沼气池的泄漏估计了农村堆肥的CH_4排放量为3.2×10~(12)g/a;根据城市、稻田附近和沙漠地区大气CH_4浓度的测量结果推算了城市CH_4排放量;根据反刍动物消耗食物总量估计了反刍家畜的CH_4排放量;根据瓦斯排放资料估计了煤矿CH_4排放量;根据文献资料估计了中国天然湿地的CH_4排放量.最后估计了中国各种源的CH_4排放总量及未来变化趋势.1988年中国CH_4排放总量为40×10~(12)g,其中一半以上来自稻田.2000年中国CH_4排放总量可达45×10~(12)g,主要是反刍动物和煤矿排放量增加. The principle, system and experiments on gas pulse deaning dust device for boiler are presented. The mixture of gas and air is ignited, and explosive buming is produced. The dusts of the boiler tail heating surface are cleaned by kindle energy scouring, sound wave vibrating and heat cleaning, and good cleaning effect is achieved. It is a plactical technique with great future. 阐述了瓦斯脉冲清灰装置的原理、系统结构及试验等,可燃性气体与空气混合后点燃发生爆炸燃烧,利用动能冲刷、声波振动和热清洗对锅炉尾部受热面的积灰进行清除。
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