Melo M V, Sant'anna G L, Massarani G
Program de Engenharia Química/COPPE/UFRJ--Universidade Federal do Rio de Janeiro C.P. 68502, 21945-970, Rio de Janeiro--RJ, Brazil.
Environ Technol. 2003 Jul;24(7):867-76. doi: 10.1080/09593330309385623.
The aim of this work is to develop alternative techniques for the treatment of waters heavily contaminated by oil. Furthermore, the treatment system should achieve high removal efficiencies even under unfavorable conditions, when oil is finely dispersed in the water phase and oil droplet sizes range from 5-30 mm and concentrations are between 100 and 300 mg l(-1). The first experiments were carried out in an induced air flotation system where a flotation column performance was evaluated in batch and continuous operation. The second system investigated in this work focused on the association of centrifugal separation in a hydrocyclone and the flotation operation. The considered system is characterized by the association of these two processes, resulting the set-up in a compact unit (centrifugal flotation system). The bubbles generation and the droplet-bubble contact are performed through a gas-liquid ejector, while the separation of the phase rich in oil (froth phase) is promoted by a hydrocyclone. In both systems, it was possible to reduce the chemical demand of oxygen by more than 85% and the oil concentration of an emulsion containing droplets with sizes between 10 and 20 mm, using Polyacrilamide as destabilizing agent.
这项工作的目的是开发用于处理受油严重污染的水的替代技术。此外，即使在不利条件下，当油在水相中精细分散且油滴尺寸范围为5 - 30毫米、浓度在100至300毫克/升之间时，处理系统也应实现高去除效率。最初的实验是在诱导气浮系统中进行的，在该系统中对浮选柱在间歇和连续操作下的性能进行了评估。这项工作中研究的第二个系统重点关注水力旋流器中的离心分离与浮选操作的结合。所考虑的系统的特点是这两个过程的结合，从而形成一个紧凑的装置（离心浮选系统）。气泡的产生以及液滴与气泡的接触通过气液喷射器进行，而富含油的相（泡沫相）的分离则由水力旋流器促进。在这两个系统中，使用聚丙烯酰胺作为去稳剂，都有可能将含尺寸在10至20毫米之间液滴的乳液的化学需氧量降低85%以上，并降低油浓度。
