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Lead can be recovered from funnel glass of waste cathode ray tubes via reduction melting. While low-temperature melting is necessary for reduced energy consumption, previously proposed methods required high melting temperatures (1400 °C) for the reduction melting. In this study, the reduction melting of the funnel glass was performed at 900–1000 °C using a lab-scale reactor with varying concentrations of Na2CO3 at different melting temperatures and melting times. The optimum Na2CO3 dosage and melting temperature for efficient lead recovery was 0.5 g per 1 g of the funnel glass and 1000 °C respectively. By the reduction melting with the mentioned conditions, 92% of the lead in the funnel glass was recovered in 60 min. However, further lead recovery was difficult because the rate of the lead recovery decreased as with the recovery of increasing quantity of the lead from the glass. Thus, the lead remaining in the glass after the reduction melting was extracted with 1 M HCl, and the lead recovery improved to 98%. 相似文献
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《International Journal of Sustainable Engineering》2013,6(3):239-257
The regeneration and adsorption of desiccant wheel for producing the dry air was experimentally investigated. The air needed for regeneration was heated in an evacuated tube solar collector with surface area 4.44 m2. The desiccant wheel is regenerated at the temperature in the range of 43.9–72.6°C. The regeneration and adsorption performances are affected by the regeneration temperature, wheel rotation, air flow rate (process and regeneration) and ambient conditions. By comparing the adsorption and regeneration performance at different air flow rate and constant rph, it was found that maximum adsorption and regeneration rates are obtained at air flow rate of 210.789 kg/h. Regeneration temperature directly affects the effectiveness of the desiccant wheel. Maximum desiccant wheel effectiveness of regeneration sector and adsorption sector is obtained at air flow rate of 105.394 kg/h. The regeneration performance of desiccant wheel with evacuated tube solar air collector is suitable for the Indian climate. 相似文献
234.
通过对三种常用管道烟气静压测定法进行理论和试验分析,推荐一种实用的静压间接测定法,并对该法进行理论分析和试验验证。 相似文献
235.
试论自然资源保护法 总被引:1,自引:0,他引:1
李爱年 《中国环境管理干部学院学报》2000,(Z1)
自然资源保护法属于环境保护法的一个组成部分。目前,我国自然资源保护法还不十分完善,与自然资源保护和经济发展的要求不相适应。本文针对自然资源保护法存在的缺陷,提出进一步完善的建议,以利于我国自然资源保护事业的发展。 相似文献
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Fernando Bonilla-Musoles Luis E. Machado Newton G. Osborne Elkin A. Muñoz Francisco Raga Javier Blanes Francisco Bonilla Jr 《黑龙江环境通报》2001,21(8):622-626
A comparison between two-dimensional (2D), and three-dimensional (3D) ultrasonography was made in four fetuses diagnosed with neural tube defect (NTD) in the first half of pregnancy. 3D ultrasonography (orthogonal and multiplanar systems) proved to be an excellent complement to 2D, particularly when using orthogonal planes. When using the 3D multiplanar surface imaging system, excellent images of the malformations can be rapidly obtained. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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