Effect of Slime and Impurity Removal as a Pre-Treatment Stage Using a Low-Grade Zinc-Oxide Sample

2019 ◽  
Vol 60 (5) ◽  
pp. 463-472
Author(s):  
Aisan Ramadi ◽  
Mohammad Noaparast ◽  
Seyed Ziaedin Shafaie ◽  
Armin Salsani
2013 ◽  
Vol 316-317 ◽  
pp. 830-833 ◽  
Author(s):  
Ming Xiao Li ◽  
Sheng Jian ◽  
Wen Juan Zhao

The zinc oxide sample from the Lanping mine located in the west of Yunnan province,China, is characterized with low grade, high calcium content, high oxidation rate and heavy slime. According to the properties of the ore, a new dressing-metallurgy combined method is proposed to process the ore and the beneficiation part is discussed by this paper. Based on the regulation of reagent scheme, flotation flowsheet of pre-desliming and two rougher is conducted to obtain a zinc concentrate that Zn grade is 18.72% at Zn recovery of 90.88%. The calcium removal rate of zinc concentrate reaches to as high as 78.15% for the flotation operation, which could lay the foundation for the next acid leaching process.


2019 ◽  
Vol 1 (1) ◽  
Author(s):  
Adele Brunetti ◽  
Francesca Macedonio ◽  
Giuseppe Barbieri ◽  
Enrico Drioli

Abstract The recent roadmap of SPIRE initiative includes the development of “new separation, extraction and pre-treatment technologies” as one of the “key actions” for boosting sustainability, enhancing the availability and quality of existing resources. Membrane condenser is an innovative technology that was recently investigated for the recovery of water vapor for waste gaseous streams, such as flue gas, biogas, cooling tower plumes, etc. Recently, it has been also proposed as pre-treatment unit for the reduction and control of contaminants in waste gaseous streams (SOx and NOx, VOCs, H2S, NH3, siloxanes, halides, particulates, organic pollutants). This perspective article reports recent progresses in the applications of the membrane condenser in the treatment of various gaseous streams for water recovery and contaminant control. After an overview of the operating principle, the membranes used, and the main results achieved, the work also proposes the role of this technology as pre-treatment stage to other separation technologies. The potentialities of the technology are also discussed aspiring to pave the way towards the development of an innovative technology where membrane condenser can cover a key role in redesigning the whole upgrading process.


Author(s):  
Teresa C. Silva ◽  
Fredrik B. Andersson

Abstract Background A lack of conceptual modeling of how the components of opioid maintenance treatment (OMT) for opioid dependence (OD) work causes it to occasionally be labeled the “black-box” of treatment. This study had a two-fold objective: First, to analyze which factors related to OMT for OD contribute to the abstinence of problematic use of non-prescribed opioids and sustain recovery, from the patients’ perspective; second, to understand which changes OMT produced in the individuals’ lives might significantly contribute to relapse prevention. Methods We used qualitative methods of design, inquiry, and analysis from a convenience sample of 19 individuals in a Swedish treatment setting. Results All the participants reported previous cycles of problematic use of non-prescribed opioids and other non-prescribed psychoactive substances, treatment, abstinence, recovery, and relapse before starting the current OMT program. During the pre-treatment stage, specific events, internal processes, and social environments enhanced motivation toward abstinence and seeking treatment. During the treatment stage, participants perceived the quality of the human relationships established with primary social groups as important as medication and the individual plan of care in sustaining recovery. From the participants’ perspective, OMT was a turning point in their life course, allowing them a sense of self-fulfillment and the reconstruction of personal and social identity. However, they still struggled with the stigmatization produced by a society that values abstinence-oriented over medication-assisted treatments. Conclusion OMT is not an isolated event in individuals’ lives but rather a process occurring within a specific social context. Structural factors and the sense of acceptance and belonging are essential in supporting the transformation. Treatment achievements and the risk for relapse vary over time, so the objectives of the treatment plan must account for characteristics of the pre-treatment stage and the availability and capacity of individuals to restructure their social network, besides the opioid maintenance treatment and institutional social care.


2011 ◽  
Vol 332-334 ◽  
pp. 568-571
Author(s):  
Yi Jun Pan ◽  
Chien Teng Hsieh ◽  
Chien Kuo Yen

The purpose of this study is to achieve a better understanding of the influences of enzymatic and caustic pretreatments on the dying adsorption behavior of Lyocell yarns. The substantivity behavior, dyeing adsorption isotherms and their correlation between the equilibrium modeling and equilibrium isotherm parameters of the pre-treated Lyocell fibers have been studied. Although the conditions of each treatment were the same, changing the processing sequences caused substantially different modifications on the Lyocell fiber fine structure with consequent effect on dyeing behaviors. In general, pretreatment by caustic soda and/or enzyme can improve their dyeability of Lyocell fibers. The results of dyes adsorption show that for the same enzymatic treatment condition if the enzymatic treatment stage is applied before the caustic pre-treatment, the dyeability and sorption ability of small molecule dye on pre-treated Lyocell can be improved over that which can be obtained for caustic pre-treated yarn.


2017 ◽  
Vol 169 ◽  
pp. 534-541 ◽  
Author(s):  
Kun Yang ◽  
Libo Zhang ◽  
Chao Lv ◽  
Jinhui Peng ◽  
Shiwei Li ◽  
...  

Author(s):  
Zhuang Li ◽  
Yijun Cao ◽  
Guihong Han ◽  
Guixia Fan ◽  
Yanfang Huang
Keyword(s):  

2019 ◽  
Vol 72 (5) ◽  
pp. 1371-1380 ◽  
Author(s):  
Faraz Soltani ◽  
Reza Aram ◽  
Mokhtar Aazami ◽  
Hossna Darabi ◽  
Mehdi Ghadiri ◽  
...  

2015 ◽  
Vol 4 (1) ◽  
pp. 112-120 ◽  
Author(s):  
Madhuka Roy ◽  
Krishnendu Kundu ◽  
V. R. Dahake

Enhanced rate of fossil fuel extraction is likely to deplete limited natural resources over short period of time. So search for alternative fuel is only the way to overcome this problem of upcoming energy crisis. In this aspect biofuel is a sustainable option. Agricultural lands cannot be compromised for biofuel production due to the requirement of food for the increasing population. Certain species of algae can produce ethanol during anaerobic fermentation and thus serve as a direct source for bioethanol production. The high content of complex carbohydrates entrapped in the cell wall of the microalgae makes it essential to incorporate a pre-treatment stage to release and convert these complex carbohydrates into simple sugars prior to the fermentation process. There have been researches on production of bioethanol from a particular species of algae, but this work was an attempt to produce bioethanol from easily available indigenous algae. Acid hydrolysis was carried out as pre-treatment. Gas Chromatographic analysis showed that 5 days’ fermentation by baker’s yeast had yielded 93% pure bioethanol. The fuel characterization of the bioethanol with respect to gasoline showed comparable and quite satisfactory results for its use as an alternative fuel.DOI: http://dx.doi.org/10.3126/ije.v4i1.12182International Journal of Environment Volume-4, Issue-1, Dec-Feb 2014/15, page: 112-120  


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