Experimental study on pumping pressure of pipeline transportation of hazardous waste

Abstract

Mixing hazardous waste such as distilled residue and hazardous waste sludge which are piped to cement rotary kilns for incineration is the optimal method of co-processing of hazardous waste in China. Solid pump can be pumped over long distances is a difficult problem because the mixture is highly viscous and belongs to solid-liquid two-phase flow mixed with iron and wood. Firstly, the composition and mechanism of pipeline pressure is studied based on the principle of pulsating solid pump. Secondly, a mathematical model of pumping pressure suitable for engineering applications combined with the temperature difference coefficient, restart coefficient and yield stress coefficient was established. Thirdly, the pipeline pressure test platform was build. The results show that the pressure loss is 3.1 kPa at 35 % sludge mass fraction and the loss conversion coefficient of horizontal 1 m∶vertical 1 m∶horizontal 90°elbow∶vertical 90°elbow is 1∶3∶16∶18. Fourthly, the recommended sludge mass fraction is 35 % ~40 % by the slump test. Finally, the experiment showed that the pumping pressure increased exponentially with the increase of sludge mass fraction and was linear with flow velocity. The temperature difference coefficient is 1.5. The restart coefficient is 1.1 and the yield stress coefficient is 1.1.

Keywords

• hazardous waste
• co-processing
• cement-kiln
• pipeline transportation
• pumping pressure
• slump
• yield stress