Biodiversity And Treatment Technology Of Ballast Water Sediments

As "International Convention for the control and management of ship's ballast water and sediment" to be implemented,port states should provide ballast water sediment reception facilities unconditionally.In order to protect the native marine environment,it is necessary to do some treatment to make the sediments,which are received,unharmful for Port states.Combining with the project in National Key Technologies R&D Program(Project No.2006BAC11B04),this thesis has analyzed the physico-chemical nature and biodiversity of ballast water sediments in different shipping lines and coastal sediments in Dalian.Then,on that basis,microwave-ultrasound and ultrasound-SO₄^-2·technologies are used to deal with the sediments, fuether,the effect of the treatment wieh the two technologied about the two kinds of sediments are concerned.It can be concluded as follows:(1) The mian types of organisms in the ballast sediment are planktonic-diatom and dinoflagellate cyst,together with few red-tide algae,c which are distributed worldwide. In the species of dinoflagellate cysts,the toxic Alexandrium cysts are dominating ones. After further analysis,it is found that the species and the quantity of algae and cysts in ballast sediment has to do with the date and location that ballast water is carried in respective shipping lines and different marine circumstances.Planktonic diatoms and some dinoflagellates are the dominating species in coastal sediments,and phytoplankton community,the composition of species and number of algae cells in the normal range, is the typical species of the North Sea.(2) It is apparent that the effect after the treatment with microwave-ultrasound and ultrasound-SO₄^-2·technologies takes on the fact that the morphological integrity of algal cells and cysts will be destroyed.(3) Via the germination rate of cysts,the further study about the effect of the treatment on the cysts with microwave-ultrasound and ultrasound-SO₄^-2·technologies is made.After the treatment of under microwave(power 400 W,30 s)and the treatment under ultrasonic(power 300W,duty cycle 1:2)for 90s,the germination rate dropped to 8%.Ultrasound-SO₄^-2·technology,treat with ultrasonic(power 300 W, duty cycle 1:2) for 30s,and then treat for SO₄^-2·,the germination rate down to 10%,is better when the concentration of SO₄^-2·is 0.7 g/L,the processing time is 30 s.