Onboard Analysis of Ballast Water

Transcription

1 Onboard Analysis of Ballast Water The SGS Sampling System Prototype 02 Technical requirements for the installation of prototype 02 for the in-line sampling of ballast water from within ballast water main pipes onboard ships (Version ) WHEN YOU NEED TO BE SURE

2 TABLE OF CONTENT 1 BACKGROUND THE SGS BALLAST WATER SAMPLING SYSTEM SAMPLING FLANGE ISOKINETIC SAMPLING PORT SAMPLING DEVICE BACKFLUSH PORT TOTAL VIEW INSTALLATION DETAILS AND DIMENSIONS SUMMARY FOR NECESSARY ON BOARD INSTALLATIONS TECHNICAL DRAWING OF DN80 PIPE AND DN80 FLANGE WELDED TO MAIN PIPE CONTACTS

3 1 BACKGROUND The Ballast Water Management Convention formulated in 2004 by the International Maritime Organization regulates the quality of the ballast water discharged from ships into the sea. To meet the defined quality standards ships have to install a ballast water treatment system. Once the convention comes into force ships have to demonstrate that the quality of their ballast water is in line with the IMO regulations. These quality standards are mainly addressing the densities of plankton organisms in the ballast water. The IMO defines three different target size classes : I. Plankton organisms larger or equal than 50µm II. Plankton organisms larger or equal than 10µm and smaller than 50µm III. Bacteria For a rapid onboard compliance analysis a system ensuring to take representative samples as well as adequate analytical methods are indispensible prerequisites. The sampling system should be able to differentiate between the IMO target size classes and the analytical methods should be orientated along the physiological characteristics of these target size classes. Within the frame of a research and development project executed by order of the Federal German Hydrographic and Maritime Agency - BSH, Hamburg, Germany, the SGS Institut Fresenius GmbH, Taunusstein, Germany developed both a new, innovative ballast water sampling system and adequate analytical methods for a rapid onboard compliance analysis. 2 THE SGS BALLAST WATER SAM PLING SYSTEM The SGS sampling system represents a closed system, that deviates ballast water from the main pipe system onboard ships and redirects the bypass volume flow back to the main pipe system. sampling system ballast water main pipe 2

4 Figure 1: schematic principle of the new SGS sampling system The system comprises these components : (1) Sampling port flange (2) Isokinetic sampling port (3) Sampling device (4) Backflush port (5) Backflush flange The ballast water from the main pipe is deviated via the sampling flange (1) installed in the main pipe. An isokinetic sampling port (2) is fixed to this flange and sampling port and sampling device (3) are connected by tubes. Having passed the sampling device the ballast water is directed by tubes to the backflush port (4) which is fixed to the backflush flange (5) installed in the main pipe. While the sampling flange (1) and the backflush flange (5) are fixed installations of the ballast water main pipes onboard ships, the isokinetic sampling port (3), the sampling device (4), the backflush port (5) as well as all connecting tubes are mobile devices and will be brought onboard and connected to the main pipe prior to the start of the sampling procedures. Under normal conditions the permanently installed sampling flange (1) and the backflush flange (5) are closed by lids. 2.1 SAMPLING FLANGE The sampling flange comprises a rather short piece of pipe with a flange at its end. It is fixed to the ballast water main pipe. Figure 2 presents a photograph of such a sampling flange with the isokinetic sampling port disconnected. This type of sampling port is required by the IMO (cf. para 2.2). 3

5 Figure 2: Sampling flange (left) with isokinetic sampling port (right) disconnected 2.2 ISOKINETIC SAMPLING PORT The isokinetic principle describes a pipe (the isokinetic pipe) with a small diameter, which is concentrically installed in a larger, main pipe. The opening of the small isokinetic pipe is facing upstream the volume flow in the main pipe (cf. figure 3). ballast water main pipe d2 d1 isokinetic sampling pipe ("L"- shape) length Figure 3: The isokinetic principle The technical specifications of the isokinetic sampling port developed for the new SGS ballast water sampling system strictly follows the IMO document Guidelines for ballast water sampling (G2) (MEPC 58/23, annex 3, Resolution MEPC.173(58), adopted 10 th October 2008) Figure 4: The isokinetic sampling port as requested by IMO 4

6 As a follow-up development SGS constructed a universal isokinetic sampling port, which allows to take samples from volume flows of in maximum 8.000m³/h (cf. figure 5). Figure 5: The universal, isokinetic sampling port The universal sampling allows for the use of isokinetic pipes with different diameter. Inserted into a cartridge the isokinetic pipes may be adequately orientated in any pipe as indicated by the yellow arrows. 2.3 SAMPLING DEVICE The sampling device comprises three major components (i) a large filterhousing, (ii) a mains independent operating volume count and (iii) a small isokinetic bypass. bypass sampling out in isokinetic bypass pressure gauge filterhousing pressure gauge Figure 6: The functional principle of the new SGS sampling device 5

7 Figure 7: Prototype 02 of the new SGS sampling device with isokinetic sampling pipe and back flush flange equipped with a volume count In the filterhousing the plankton organisms with a size of larger or equal than 50µm are collected by means of a stainless steel screen with adequate apertures. The samples for the other IMO target size classes are collected via the isokinetic bypass. The prototype 01 of the new SGS sampling device (cf. figure 7) has a small footprint (50x60cm), a moderate height (80cm) and a rather low weight (approx. 10 kg). All materials are stainless steel. Dismantling of the sampling device for disinfection is easy. 2.4 BACKFLUSH PORT The backflush port comprises a simple flange with a connected short pipe and a ball valve. Figure 8: Backflush port of the new SGS sampling system equipped with volume count 6

8 2.5 TOTAL VIEW Figure 9: Sketch of SGS prototype 02 installed to a ballast water main pipe. 7

9 3 INST ALLATION DET AILS AND DIMENSIONS To adequately connect the new SGS sampling system with the main ballast water pipe a sampling port and a back flush port have to be fixed to the main ballast water pipe. According to the IMO regulations for the International Ballast Water Management Convention as stipulated in the IMO document Guidelines for ballast water sampling (G2) (MEPC 58/23, annex 3, Resolution MEPC.173(58), adopted 10 th October 2008) the sampling flange should be installed in the discharge line as near to the ballast water discharge point overboard as practicable. Sampling Port ballastwater main pipe minimum 70 mm DN 80 pipe DN 80 flanges 3 inch ball valve DN 80 flange to sampling system Back Flush Port ballastwater main pipe minimum 70 mm DN 80 pipe DN 80 flanges 3 inch ball valve DN 80 flange from sampling system Figure 10: Sampling port and back flush port (sketch) As presented in figure 9 both ports necessary to install the SGs ballast water sampling system to the on board ballast water main pipe have the same characteristics : a short piece of DN 80 pipe is welded to the ballast water main pipe and a DN 80 flange is fixed to this short piece of DN 80 pipe. 8

10 A 3 inch ball valve, which carries two DN 80 flanges, is fixed to the DN 80 flange, which is welded to the ballast water main pipe. The open DN flange is closed by a blind flange. Before the SGS ballast water sampling system is installed the 3 inch ball valve is closed and the blind flange is dismantled. In the next step the universal sampling port (cf. figure 5) is installed and the 3 inch ball valve is opened. The isokinetic pipe is pushed into the correct position within the ballast water main pipe to ensure it is concentrically orientated and the opening is facing upstream for true isokinetic sampling. The back flush port is installed accordingly. The following figures display the single parts and the entire installation at the ballast water main pipe. Figure 11: a) welded DN80 pipe and DN 80 flange; b) 3 inch ball valve with two DN 80 flanges; c) installed ball valve with flanges 9

11 This combination of flanges and ball valve will secure that the main ballast water pipe must not be emptied for the installation of the SGS ballast water sampling system and during the sampling procedures. 4 SUMM ARY FOR NECESSAR Y ON BO ARD INST ALLAT IONS The installation of the two ports necessary for the SGS ballast water in line sampling system comprises: Sampling Port Piece of DN 80 pipe welded to ballast water main pipe DN 80 flange welded to DN 80 pipe DN 80 flange Back Flush Port Piece of DN 80 pipe welded to ballast water main pipe DN 80 flange welded to DN 80 pipe DN 80 flange 3 inch ball valve 3 inch ball valve DN 80 flange DN 80 blind flange (lid) DN 80 flange DN 80 blind flange (lid) 10

12 5 TECHNICAL DRAWING OF DN80 PIPE AND DN80 FLANGE WELDED TO M AIN PIPE 11

13 6 CONT ACTS Dr. Lothar Schillak 0049-(0) Peter-Paul Stehouwer 0049-(0) Visit the ballast water website at