Basic Research On Fast Detection Method Of Sewage Aboard Ships

The problem of the discharge of the sewage aboard ships has attached a lot of attention of many countries. Both International maritime conventions and domestic laws have made clear regulations on the water quality of the sewage. However, sanitary sewage testing equipments used in terrestrial laboratory can’t be applied in the test of the discharge of sewage aboard ships because of the constraints of the time and the space. China Maritime Safety Administration judges the water quality of the ship sewage just by exam the operating conditions of the equipment and the validity of the certificate. It is a simple law enforcement as well as qualitative enforcement.First, this paper introduces the environmental harm caused by the indiscriminate discharge of the sewage aboard ships, the shortage of the test of the ship sewage during the enforcement of the maritime law, and the methods of the bacterial counting applied in the library in the present. This paper proposes a new ship sewage rapid detection device design, this device is based on a microfluidic chip technology and laser-induced fluorescence detection principle, rapid quantitative detection of the number of E. coli in the sewage aboard ships. This paper focuses on the development of the rapid detection device of the sewage. The results of the experiments indicate that the operation of this rapid detection device is feasible. The details of the main work are as followed.(1) The structural design and production process of microfluidic chips. According to the requirement of the detection device, the paper make great efforts to optimize of the production process of the microfluidic detection chips, so that the microfluidic chips can be made easily and quickly.(2) The selection of the way of the drive aggregation. In order to make sure that the bacteria can pass the microfluidic chip detection area one by one, it is necessary to choose a proper way of the drive aggregation. Many comparative experiments have been done to compare the pressure-driven gathering way and electroosmotic flow-driven gathering way, the optimal microfluidic drive and control ways can be determined. What’s more, based on the results of the FLUNT simulations software, the relationship of focus width and the width ratio of the sheath liquid/sample channel is shown. (3) The set up of the test-bed and the test of the rapid detection device. According to the design of the detection device, the selection of related parts and the production of the signal amplification circuit have been done. After the detection device is set up completely, the detection capability of this device has been got after a large number of experiments.