选磷厂废水电化学处理循环利用

简要介绍磷矿浮选厂废水（尾矿水）进行电化学处理的研究和处理后循环使用的浮选工艺试验以及含固废水电化学处理的理论基础。试验结果表明：经电化学处理后的废水达到工艺用水水质控制指标；反复循环使用于浮选工艺取得满意效果；电化学处理方法是实现工业废水循环利用的有效手段。     

海口浮选厂尾矿库回水利用方案探讨

云南磷化集团海口200万吨/年浮选厂尾矿库的沉清水,通过水处理,消除回水中对正浮选作业影响的有害离子,处理后的回水返回到浮选作业中循环使用,实现了尾矿水零排放。     

胶磷矿正反浮选尾水电化学处理利用研究

为了解决胶磷矿正—反浮选尾矿水的污染和回用问题,采用了电化学处理方法。经试验证明经处理的尾矿水中PO_4~(3-)去除率达90％以上,可以部分回用并节省Na_2CO_343％。这一处理方法具有一定的实用价值。     

云南某风化胶磷矿选矿及尾矿库回水利用研究

针对云南某风化胶磷矿进行了选矿及尾矿库回水用于浮选的试验研究。原矿P2O5品位为24.74%,MgO质量分数仅为0.20%。根据原矿性质,试验采用在磨矿后对矿样进行分级,然后再进行浮选的选矿工艺流程。在浮选指标相近时,正浮选回水流程的药剂用量较清水流程高,而反浮选回水流程的药剂用量明显低于清水流程,最终反浮选回水流程也可获得P2O5品位为28.62%,P2O5回收率为96.14%,MgO质量分数为0.17%的磷精矿产品,且反浮选所使用的回水是没有经过处理的回水。因此,尾矿库回水用于该风化胶磷矿的反浮选作业具有一定的可行性。     

云南晋宁磷矿浮选废水处理研究

在磷矿的正反浮选中,由于矿浆不同的pH值条件,磷矿石的多样性,矿浆中无机离子及药剂组份表现出不同的特性,正浮选尾矿水、反浮选精矿水及反浮选尾矿水差异性很大,将所有选矿废水集中收集,不经处理统一回用显然是行不通的。絮凝沉淀法是处理晋宁磷矿浮选废水的有效方法之一,石灰与碳酸钠或磷酸钠配合使用都可以用来处理浮选废水。当氧化钙用量为4.0 kg/m3、碳酸钠用量为0.6 kg/m3时,闭路流程试验最终精矿w(P2O5)=29.66%,回收率达77.38%;当氧化钙用量为2.0 kg/m3、十二水磷酸钠用量为0.2 kg/m3时,最终精矿w(P2O5)=30.22%,回收率76.74%。此方法处理后的废水回用对浮选过程影响不大,且简单易行,工业上容易实施。     

水总硬度对脂肪酸类捕收剂的影响初探

采用胶磷矿单一反浮选回水配制捕收剂,研究回水不同总硬度对胶磷矿捕收剂浮选效果的影响,结果表明水总硬度大于905 mg/L时,脂肪酸类捕收剂将与回水中的钙、镁离子发生络合反应,影响捕收剂的浮选效果。     

云南晋宁磷矿选矿回水对浮选指标影响的研究

采用模拟回水对晋宁磷矿进行了浮选试验研究,研究了回水中钙镁离子、磷酸根离子、硫酸根离子等有害离子对浮选指标的影响,结果表明:钙镁离子对浮选指标影响较大,磷酸根离子、硫酸根离子等对浮选影响不大,用碳酸钠和磷酸钠处理模拟回水效果较好,其中碳酸钠的效果更好一些.     

宜昌胶磷矿浮选扩大连续试验和选矿废水利用

根据矿石的性质，采用正-反浮选流程选别宜昌磷矿，工艺合理，产品质量较好，是开发利用宜昌磷矿的一个新途径基于磷矿浮选工艺要求和废水的性质，利用CaO和Na2CO3两碱处理选矿废水，废水循环回用，达到回水100％的利用．该工艺既防止了废水对环境的污染，降低了浮选药剂消耗，又充分利用了水资源，工艺简单，易于工业化.     

磷矿浮选回水利用研究与建议

针对磷矿浮选工业化生产中回水利用存在的问题,进行回水考查及处理工艺研究,发现回水中的Ca2+、Mg2+、SO42-、PO4-含量过高是影响磷矿正浮选的主要因素,为合理有效利用回水提出了改进建议。     

磷矿浮选药剂对尾矿澄清性能的影响

采用一种简易方法考察了常用磷矿浮选药剂对浮选尾矿澄清性能的影响.结果表明:该试验方法误差较小,可以用于评价浮选药剂对浮选尾矿澄清性能的影响.在海口磷矿浮选药剂中,调整剂水玻璃对浮选尾矿澄清性能影响最大,其次为MW.捕收剂用量对浮选尾矿澄清性能影响较小,但捕收剂的种类则对浮选尾矿的澄清性能影响较大.使用工业捕收剂H969浮选的尾矿澄清性能要远低于使用工业油酸时尾矿的澄清性能.增效剂的使用可提高浮选尾矿的澄清性能.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.