Small cutter suction dredgers have been widely used in environmental dredging of rivers and lakes. However, due to the insufficient pumping pressure and large transmission resistance, the transmission distance of the cutter suction dredgers can not meet the requirements of engineering. According to the actual demand, this paper carried out the research on the air added technology of small diameter, analyzed the influence of the air added technology on the pipeline transportation, and improved the problem of short transmission distance caused by the large transportation resistance of the small diameter cutter suction dredger. At the same time, relying on the actual project, this paper carried out the field test of air added technology of DN400 diameter sludge discharge pipeline, and researched the location of air added point along the pipeline, three air adding methods, and the comparison of economic benefits between the scheme of air added and pump. The results show that the air added technology is beneficial to improve the transportation distance of small cutter suction dredger and reduce the unilateral cost of dredging transportation.
Dredging engineering is inseparable from the long-distance transportation of slurry. Improving the transportation performance of pipeline has always been the key research direction of dredging and filling engineering. The methods to improving the conveying performance mainly include the following ways: optimizing the performance of power equipment and improving the working efficiency of them; changing the basic parameters of the transmission pipeline, optimizing the pipeline layout, and adopting small resistance pipeline; improving the characteristics of conveying slurry and reducing the internal resistance of slurry. The first two methods require a lot of capital investment for equipment renewal and iteration, while the way of reducing slurry conveying resistance has little change to the original layout and can be implemented quickly.
Air added in pipeline is a technology to boost pipeline transportation by changing the slurry resistance inside the pipeline. The technology can reduces the resistance between the pipeline and the slurry effectively. As a drag reducer, air has the advantages of no pollution, easy access and no treatment. The air added equipment has the characteristics of simple installation, simple operation and low equipment loss. Therefore, there are many scholars have studied pipeline air added technology.
