磷回收利用——面向未来的污泥处理技术

通过定向控制MAP沉淀过程，可以对生物除磷工艺进行优化处理，从而明显改善消化污泥的脱水性能，降低磷返回负荷。

采用诱导沉淀法进行污水磷回收

在生物除磷污水处理厂内，储磷细菌内的一部分多聚磷会在厌氧情况下重新返溶进入液体，经常会在厌氧污泥消化罐内出现很高浓度的正态磷，使得污泥内存在的亲水性胶体系统变得更加稳定，并导致污泥脱水性能变差。此外，根据pH值情况会在污泥消化塔的管道系统和脱水设备内产生麻烦的尿粪石沉积现象；污泥水内磷浓度很高，导致返回污水厂生物系统的磷返回负荷很高。所有这些都会导致市政污水处理厂产生很高的运转费用和保养维修费用。

含磷废水处理技术的研究进展

降低废水中磷的浓度是抑制水体富营养化的关键。处理含磷废水的方法有化学沉淀法、吸附法和生物法,本文分别介绍了3种处理方法的原理、特点及技术发展现状。对含磷废水处理技术的发展和废水中磷的回收利用进行了讨论。

承德转炉钢渣主要成分的测定及高效除磷条件的研究

对钢渣中二氧化硅、氧化钙以及氧化镁等主要成分进行测定,在此基础上利用酸浸法探究钢渣脱磷的最适宜酸条件,得到硝酸脱磷率最高。以此为条件探究酸含量、钢渣粒度等因素对钢渣除磷的影响,同时将表面活性剂引入钢渣除磷中,通过创新并改进实验中表面活性剂质量分数,得到了良好的实验效果,实验发现没食子酸正丙酯具有较好的除磷效果,在很大程度上实现了钢渣高效除磷。

Recycling and Reusing Heat Energy During the Production of Powdery Phospholipid

The temperature is 56.5℃when acetone gas is rectified during the production of powdery phospholipid. If heat exchanger is added, heat energy that is reclaimed can be used by other heaters. On the basis of exchange hot water （51℃） 4m3 every minute, a factory with the productivity of powdery phospholipid being 10 ton a day can save 533.2 ton standard coal which is equivalent to 746.48 ton common coal. If this technique of saving energy and reducing emission could be widely used in correlative industries of all over the country, economic benefits will be prominent.

Flocculation of the Moroccan phosphates slimes

In Morocco, the phosphate industry generates by washing during the ore beneficiation in humid way, big quantities of sludge loaded in fine mineral particles （or slimes） with contents of water in the order of 90-95%. The specific consumption in water for the beneficiation of one tone of dry ore is approximately 0.6 m3. The management of this sludge and the recycling of process water are played to a schema of solid-liquid separation by flocculation, settling then stocking in basins of several dozens hectares. Recovered clear waters are recycled into the circuit of washing. The principal motivation of this work which is a part of EL MAA project is dedicated to the study of the impact of the speed of agitation on the flocculation behavior in terms of dewatering of the phosphate slimes and recycling of the process water. Study was driven on sample of slimes taken in entrance of the thickeners of a Moroccan washing plants, before flocculation. The raw slimes have a concentration in solid of 75.5 g·L^-1, a P205 grade of 17.3% and a free settling velocity 9 cm·h^-1. Fine fraction -2 μm, responsible for the poor settling of slimes is composed in practice of nearly 96% of smectite. It represents 9% of the dry solid content in the slimes. Measurements reveal important variations of the granulometric and textural properties of large floes in response to flocculation, opening ways of optimization for the velocity gradient.

两种水生植物组合对网箱养殖长吻水体氮磷污染物的净化作用

为了减少网箱养鱼对养殖水体的污染,探寻环保型网箱,实现网箱养鱼的可持续发展,以筛选得到的漂浮植物大薸(Pistia stratiotes)和沉水植物金鱼藻(Ceratophyllum demersum)为研究对象,通过设置金鱼藻-大薸混养生态网箱与传统网箱进行对比,考察其对网箱养殖长吻氮磷排放的影响。试验结果表明,生态网箱氮和磷的回收率分别为49.86%±0.94%、38.07%±0.62%,传统网箱氮和磷的回收率分别为44.60%±0.85%、33.17%±0.58%,生态网箱与传统网箱氮磷的回收率均有显著性差异(P<0.05)。生态网箱氮和磷的利用率分别为28.13%±1.48%和16.95%±1.09%,传统网箱氮和磷的利用率分别为26.40%±1.89%和15.64%±1.47%,生态网箱氮磷利用率稍高于传统网箱,但两者之间差异不显著(P>0.05)。通过分析网箱养鱼系统中氮和磷输入和输出的途径及其总量,当网箱面积与大薸和金鱼藻种植面积为1∶17.00左右时,养殖长吻网箱的氮和磷为零排放。