Development of Resource Recovery System for Phosphate and Fluoride Using Waste form Marine Industries

(1)磷酸盐的回收：研究了在Cu（II）存在下用氧气氧化亚磷酸溶液的动力学。在373 K、3atm、pH 3、[Cu（II）] 1.0 × 10 ~（-1）mol/cm ~ 2、200分钟的保留时间内，很容易实现90%以上的氧化<-3><-3>。认为自氧化反应可用于回收化学镀废液中的磷酸盐。(2)工业废水除氟：研究发现，大气中的CO_2会干扰除氟效果，并通过形成碳酸钙而产生大量污泥。为了证实这些现象，在正常和脱气条件下使用真实的废水进行实验，不仅测量废水中的氟化物浓度，而且表征所形成的污泥的性质。因此，从最小排放的角度来看，脱气条件下的氟化钙法是一种非常有前途的含氟废水处理方法。(3)氟回收系统的开发：从生态技术的角度对一种新型的废水除氟系统进行了评价。采用活性氧化铝柱除氟装置，可在不增加处理水化学成分的情况下实现除氟。但该系统在活性氧化铝饱和后必须再生，以减少其排放。为此，我们提出了一种将吸附和氢氧化铝共沉淀联合收割机相结合的生态技术氟处理系统，以氟化钙的形式去除系统中的氟。结果表明，该系统具有节能、节材的优点，具有广阔的应用前景。

(1) Recovery of phosphate : The kinetics of the oxidation of phosphorous acid solution with oxygen in the presence of Cu (II) was studied. The achievement of oxidation above 90% is readily done at 373K, 3 atm, pH 3, [Cu (II)] 1.0Χ10^<-3>moldm^<-3> during the retention time of 200 minutes. It was considered that autoxidation reaction may be applicable to the recovery of phosphate in spent electroless plating liquors.(2) Fluoride removal from industrial wastewater : It is found that CO_2 in the atmosphere interferes with fluoride removal efficiency and produces a large amount of sludge by forming calcium carbonate. In order to confirm these phenomena, experiments using real wastewater under normal and degassed conditions were carried out not only by measuring the fluoride concentration in the wastewater, but also by characterizing the properties of the formed sludge. As a result, the calcium fluoride method under degassed conditions is suggested to be a very promising method for treatment of wastewater containing fluoride from the viewpoint of minimum emission.(3) Development of fluoride recovery system : A novel system of fluoride removal from wastewater was assessed from the viewpoint of "Ecotechnology". The equipment with activated alumina in a column can remove fluoride without increment of any chemical components in treated water. However, this system must be regenerated after activated alumina saturating, in order to minimize the emission derived from it. Then, we proposed an ecotechnological fluoride treatment system, which is composed to combine the adsorption and co-precipitation with aluminum hydroxide, and fluoride was removed as calcium fluoride from the system. As a result, the system is suggested to be very promising because of it's possibility of energy saving and resources saving.