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11.
Microalgae,a sustainable source of multi beneficial components has been discovered and could be utilised in pharmaceutical,bioenergy and food applications.This study aims to investigate the sugaring-out effect on the recovery of protein from wet green microalga,Chlorella sorokiniana CY1 which was assisted with sonication.A comparison of monosaccharides and disaccharides as one of the phaseforming constituents shows that the monosaccharides,glucose was the most suitable sugar in forming the phases with acetonitrile to enhance the production of protein(52% of protein).The protein productivity of microalgae was found to be significantly influenced by the volume ratio of both phases,as the yield of protein increased to 77%.The interval time between the sonication as well as the sonication modes were influencing the protein productivity as well.The optimum protein productivity was obtained with 10s of resting time in between sonication.Pulse mode of sonication was suitable to break down the cell wall of microalgae compared to continuous mode as a lower protein yield was obtained with the application of continuous mode.The optimum condition for protein extraction were found as followed:200g/L glucose as bottom phase with volume ratio of 1:1.25,10s of resting time for ultrasonication,5s of ultrasonication in pulse mode and 0.25g of biomass weight.The high yield of protein about 81% could be obtained from microalgae which demonstrates the potential of this source and expected to play an important role in the future.  相似文献   
12.
贵州是煤炭资源大省,作为本省的主要能源,煤炭和电力一直扮有重要角色,随着“西电东送”工程的实施,煤炭的大量利用以及电厂装机的大幅增加,导致粉煤灰的排放量急剧增加,严重污染了当地的环境,因此,对粉煤灰的利用显得迫切。对贵州某地粉煤灰进行测定的基础上,进行了浮选条件试验,并对浮选产品进行扫描电镜、X射线衍射分析,通过对粉煤灰浮选试验进行单因素考察,发现浮选浓度、浮选药剂用量是分选效果最重要的影响因素,浮选效果是浮选产品利用的关键。  相似文献   
13.
针对江西× ×难选胶磷矿,采用单一正浮选工艺进行试验.试验对各主要影响因素逐一研究分析,获得了最佳药剂制度,并在此基础上有针对性的进行了三组闭路试验,均获得了较满意的选别指标,满足了选矿厂的不同需求.研究结果为该胶磷矿的开发利用提供了技术支持.  相似文献   
14.
This article extends the earlier work (Haavisto et al. 2008. Optical spectrum based measurement of flotation slurry contents. Int. J. Miner. Process. 88 (3–4), 80–88), where visible and near-infrared (VNIR) reflectance spectroscopy was used together with an X-ray fluorescence (XRF) analyzer to improve the assaying of zinc flotation concentrate. Especially the sampling interval of the assay could be drastically reduced by the presented approach. In this study, a multichannel VNIR spectrum analyzer is utilized to measure the spectrum of the seven most important slurry lines in copper and zinc flotation circuits. Recursive data-based modeling is applied to the VNIR spectrum data and XRF assays to calculate and adaptively maintain the calibration model. The accuracy of the VNIR assays is evaluated in all the lines, and the benefits of the obtained high frequency assays in detecting oscillations and sudden grade changes are demonstrated.  相似文献   
15.
阐述了自吸式充气浮选柱与浮选机工作原理的区别,并以察尔汗光卤石矿为例,在实验室对自吸式充气浮选柱和槽式浮选机就药剂实验和矿浆比实验的浮选效果进行了比较。实验结果表明,在达到同样的氯化钾的品位的条件下,柱浮选比槽式浮选具有操作流程简单,钾的收率高等优点。  相似文献   
16.
针对湖南省××磷矿矿石性质及可选特性,采用擦洗脱泥—浮选联合工艺选别,有效降低了能耗和药耗,使P2O5品位由15.78%富集至30.77%,P2O5回收率为82.40%,磷精粉达到酸法加工用磷矿石一等品Ⅰ级标准。  相似文献   
17.
文章在介绍当前含稀土磷矿石综合利用现状的基础上,总结了近年来国内外含稀土磷矿浮选捕收剂的研究进展,并指出了今后含稀土磷矿石捕收剂的研发趋势。  相似文献   
18.
Long-chain amines, used in potash ore flotation as collectors, are insoluble in NaCl–KCl saturated brine. In commercial applications, these amines are melted at 70–90 °C, dispersed in acidic solution of hydrochloric or acetic acids, and such emulsions are then introduced to the flotation pulp.To model the commercial potash ore flotation process, dodecyl amine, used in this study, was melted at 70 °C, dispersed in hydrochloric acid aqueous solution and was added to a KCl–NaCl saturated brine at room temperature. This results in the precipitation of the amine. The present study summarizes the influence of the conditions on the particle size and morphology of the precipitating amine particles. Methyl isobutyl carbinol (MIBC), common frother in flotation processes, was shown to affect amine dispersion when added into a hot amine emulsion prior to mixing with a saturated brine. This study demonstrates that the precipitating amine particles are selectively abstracted by KCl particles, but not by NaCl particles.  相似文献   
19.
20.
Flotation tests of synthetic mixtures of celestite (SrSO4) and calcite (CaCO3) minerals using sodium dodecyl sulfonate as collector were carried out using a factorial experimental design 23. The independent experimental variables included celestite grade in the feed (50% and 90% SrSO4), conditioning pH (6.5 and 9) and sodium silicate depressant concentration (10−5 and 10−3 M). All experiments were performed at a constant collector concentration (10−4 M) and conditioning time of 15 min. The response variables were recovery and grade of SrSO4 in the concentrate.The factors that had the greatest effect on the grade and recovery of celestite were the celestite grade in the feed (L) and the depressant concentration (C); also the combination of these factors significantly affected the response variables. The highest celestite yield (96% recovery, 98% grade) was obtained when a 90% of celestite grade in the feed was used.  相似文献   
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