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991.
992.
矿区资源循环绿色体系构建 总被引:1,自引:1,他引:0
为发展矿区资源循环利用联动体系、构建层级产业集成模式、实现绿色生态矿山建设,基于代谢、集成和生态学理论,建成了符合矿区资源流动规律和经济规律的层级绿色循环体系。结果表明,把握资源间关系,合理对资源集成规划,能减少废弃资源的利用成本,并加大资源利用效率; 提高资源循环再利用意识,对促进矿区产业联动、提高矿区生态质量、增加产业收入有较大帮助。 相似文献
993.
《中国有色金属学会会刊》2020,30(8):2239-2255
Top ash from hot-dip galvanizing plant was investigated as a source of secondary zinc to be returned to galvanizing bath. The waste material contained 63% Zn as metallic, oxide and hydroxychloride phases. It was leached in H2SO4 solutions (20% and 25%) at various bath loadings (100−300 g/L). Leaching behaviors of zinc, manganese, iron and chloride ions were investigated. A few strategies of iron elimination from leaching liquors were examined. Flocculant addition was harmful for subsequent filtration of iron precipitates due to increased viscosity of solution, while a combination of zinc oxide and calcium carbonate for rising pH resulted in the formation of dense suspension unenforceable to separate from zinc sulphate solution. Zinc electrowinning was carried out at different pH (from −0.5 to 2.8) using a range of current densities (3−10 A/dm2). Optimal conditions for pure metal recovery were: leaching in 20% H2SO4 solution at zinc ash content 100−150 g/L, Fe2O3·xH2O precipitation using H2O2 and CaCO3, zinc electrowinning at pH of 0.1−1.0 at 3−6 A/dm2. Correlations between pH and free H2SO4 concentration in electrolyte solutions were also discussed. pH−acid concentration dependence for zinc electrolyte was between experimental and calculated curves for pure H2SO4 solutions, while the curve was shifted towards lower pH if ferric ions were in the solution. 相似文献
994.
杨旸 《皮革制作与环保科技》2022,(3):175-177
以橡胶制品行业和塑料制造行业为例,分析了《排放源统计调查产排污核算方法和系数手册》在污染物产排量核算过程中存在的一些问题,并提出了几点建议. 相似文献
995.
996.
Adaptive material systems and their non‐destructive characterisation Smart materials based on carbon fiber‐reinforced plastics with embedded piezoceramic sensors and actuators are expected to be a favorite composite for vibration damping and noise reduction. Due to the wide variety of physical properties of the components various damage mechanisms may reduce the sensing and actuating capabilities of the piezoceramic material. Comprehensive non‐destructive characterization and integral health monitoring help to optimize the structure and its manufacturing and are an essential prerequisite to ensure performance and availability of smart components during their life time. 相似文献
997.
玻璃钢衬里施工一直以手糊法为主进行,因而施工质量难以保证。通过分析硫酸、磷肥、冶炼企业设备玻璃钢内衬防腐中的影响因素:基层表面处理、底漆选择、原材料选择、施工方法及施工环境、热处理方法等,提出正确的施工方法,以避免或减少玻璃钢内衬防腐质量问题的发生。 相似文献
998.
Compatibilizing effects of ethylene/propylene (EPR) diblock copolymers on the morphology and mechanical properties of immiscible blends produced from recycled low‐density polyethylene (PE‐LD) and high‐density polyethylene (PE‐HD) with 20 wt.‐% of recycled poly(propylene) (PP) were investigated. Two different EPR block copolymers which differ in ethylene monomer unit content were applied to act as interfacial agents. The morphology of the studied blends was observed by scanning‐ (SEM) and transmission electron microscopy (TEM). It was found that both EPR copolymers were efficient in reducing the size of the dispersed phase and improving adhesion between PE and PP phases. Addition of 10 wt.‐% of EPR caused the formation of the interfacial layer surrounding dispersed PP particles with the occurrence of PE‐LD lamellae interpenetration into the layer. Tensile properties (elongation at yield, yield stress, elongation at break, Young's modulus) and notched impact strength were measured as a function of blend composition and chemical structure of EPR. It was found that the EPR with a higher content of ethylene monomer units was a more efficient compatibilizer, especially for the modification of PE‐LD/PP 80/20 blend. Notched impact strength and ductility were greatly improved due to the morphological changes and increased interfacial adhesion as a result of the EPR localization between the phases. No significant improvements of mechanical properties for recycled PE‐HD/PP 80/20 blend were observed by the addition of selected block copolymers. 相似文献
999.
随着社会经济的发展和科学技术的不断提高,对煤矿机电设备安全和生产效率的要求也越来越高,机电设备折旧与维修关系到企业的经济效益和正常的生产流程。就设备折旧维修工作中存在的问题展开论述,对煤矿机电设备正确、科学地保养、维修、废物利用进行了研究,以期为日后相关工作的顺利进行提供参考和借鉴。 相似文献
1000.
为攻克目前污泥水热产物价值相对较低、水热液过剩等问题,提出将水热液作为水热介质多次循环利用的工艺方案。通过分析污泥中氮、磷及有机质等重要资源在水热固、液相中的转化及分配规律,探究水热液循环利用在提高污泥水热产物价值、节约水资源方面的可行性和潜在优势。结果表明:水热液循环利用促进液相产物中氮、磷成分积累,在250℃水热条件下,3次循环后液相氨氮质量浓度高达17 000 mg/L,液相总磷质量浓度为200 mg/L,分别是一次水热结果的4倍和5倍,显著提升水热液的资源回收效率;水热液循环利用促进水热固相的成炭过程,有助于提高污泥水热炭化产物的利用价值。通过调控水热反应强度、增加水热液循环次数,可实现水热产物价值最大化,同时提升水资源利用效率。研究结果可为水热法实现市政污泥高效减量化、资源化利用提供理论和技术支撑。 相似文献