Pesca Pubblicazione scientifica Study of the CLB Mining System For Nodule & Crust Recovery FILONE TECNOLOGICO TEMA produzione e cattura RIASSUNTO ABSTRACT:The Continuous Line Bucket (CLB) is a mechanical system using an endless loop of rope suspended from ''a surface platform to reach the seabed and to which dredge buckets are attached at regular intervals. The Turning CLB is a recent important innovation; by steering the vessel in a circular track, trailing the empty buckets over the stern and bringing UP the loaded buckets amidships from within the arc of the ship''s track a good separation of lines has been achieved. Improvements to the CLB components which have been tested recently include: horizontal traction wheels and ball rollers used in combination to decrease the number of traction wheels by half; new bucket guides and dumping device to automate discharge of the loaded buckets without removing them from the line: and small model test for bucket guides was done. double braided polyester/nylon rope adopted to increase the life of the rope; and various bucket configurations including a piano wire mesh bucket designed by the French Group IFREMER. Filling efficiencies of over 60% were recorded for the buckets. The CLB system was evaluated for nodule deposits in 5.000 mwater depth. for three sizes of ship (15.000 t. 30,000 t and 60,000 t), and three production rates (500tld. 1.000tld and 2.000t/d). Rope sizes selected for the evaluation were 110 mm for 500 t/d. 150 mm for 1.000 t/d and 210 mm for 2, 000 t/d. Two 8 ton ball rollers and 6 traction wheels for the traction device were estimated to cost about 6 million dollars for the case of 1.000 t/d. Rope and buckets were costed as consumables. With a rope life of 1-1.5 years. unit production cost was estimated at $109/t for 500 t/d. $76. 7/t for 1.000 t/d. and $ 54. lit for 2.000 t/d in 1994 study. DATA Data di pubblicazione: 14/06/2013 AUTORI MASUDA Y CRUICKSHANK MJ ENTE DI AFFERENZA RYOKUSEISHA CORP UNIV HAWAII RIVISTA First ISOPE Ocean Mining Symposium, 21-22 November, Tsukuba, Japan