Abstract: An offshore structure is separated into an upper structure and a lower structure. Part or whole of the lower structure is kept in an upright standing state in water. The upper structure is moved to above the lower structure kept in the upright standing state. A uniting step includes one or both of raising the lower structure to arrange the lower structure on a lower side of the upper structure and lowering the upper structure to arrange the upper structure on an upper side of the lower structure by submerging part of a carrier vessel on which the upper structure is mounted while being held by a pair of arm-shaped structures of the carrier vessel and integrating the lower structure with the upper structure. In this way, an offshore structure is moored safely at an offshore installation site without using a crane vessel.

Abstract: A system includes mooring lines arranged respectively in three to eight directions, and at least one of a plurality of offshore structures included in the offshore structure group is moored by locking the mooring lines in the respective directions with separate mooring bases, and at least one of the mooring bases locks the mooring lines which are connected respectively to three to eight of the offshore structures in the offshore structure group. With this configuration, even when part of the mooring lines mooring the offshore structures is broken or the mooring function of the mooring bases is lost, although the offshore structure moves, the offshore structure is kept being moored by the remaining mooring-line group, so that the offshore structure can be prevented from colliding with another offshore structure.

Abstract: A guide plate having depressed portions is provided between an array of heat exchanger tubes, herein after “tubes”, arranged horizontally side-by-side and a next lower array of tubes arranged horizontally side-by-side, and is positioned with the lowest parts of the depressed portions near crest portions of respective lower tubes. The guide plate conveys a liquid D on outer surfaces of respective upper tubes onto similarly positioned lower tubes even when the tubes move in a right-and-left direction. A falling film heat exchanger installed in a ship, an offshore structure or the like can avoid reduction in heat exchange performance, even when the ship or the like inclines and swings, by substantially evenly distributing and dropping a liquid onto the crests of the tubes and causing the liquid dropped from the tubes located in an upper array to fall onto the tubes located in the next lower array.

Abstract: In a bubble lift system, a pressurized chamber at an upper end portion of a riser pipe applies a pressure to an upper portion inside the riser pipe to suppress an increase in the volume ratio of bubbles to a fluid mixture rising inside the riser pipe in a shallow water region. The upper end of the riser pipe is not opened to the atmosphere but is inserted into the pressurized chamber under a high pressure to thereby prevent expansion of the bubbles and gas. In addition, a deaerator for discharging bubbles separated by a centrifugal force is also provided in a middle portion of the riser pipe in a shallow water region to distribute the bubbles more evenly inside the whole riser pipe. The bubble lift system and a bubble lift method thus provided are efficient and employable even in a deep water region.

Abstract: An offshore structure is separated into an upper structure and a lower structure. Part or whole of the lower structure is kept in an upright standing state in water. The upper structure is moved to above the lower structure kept in the upright standing state. A uniting step includes one or both of raising the lower structure to arrange the lower structure on a lower side of the upper structure and lowering the upper structure to arrange the upper structure on an upper side of the lower structure by submerging part of a carrier vessel on which the upper structure is mounted while being held by a pair of arm-shaped structures of the carrier vessel and integrating the lower structure with the upper structure. In this way, an offshore structure is moored safely at an offshore installation site without using a crane vessel.

Abstract: A system includes mooring lines arranged respectively in three to eight directions, and at least one of a plurality of offshore structures included in the offshore structure group is moored by locking the mooring lines in the respective directions with separate mooring bases, and at least one of the mooring bases locks the mooring lines which are connected respectively to three to eight of the offshore structures in the offshore structure group. With this configuration, even when part of the mooring lines mooring the offshore structures is broken or the mooring function of the mooring bases is lost, although the offshore structure moves, the offshore structure is kept being moored by the remaining mooring-line group, so that the offshore structure can be prevented from colliding with another offshore structure.

Abstract: A guide plate having depressed portions is provided between an array of heat exchanger tubes, herein after “tubes”, arranged horizontally side-by-side and a next lower array of tubes arranged horizontally side-by-side, and is positioned with the lowest parts of the depressed portions near crest portions of respective lower tubes. The guide plate conveys a liquid D on outer surfaces of respective upper tubes onto similarly positioned lower tubes even when the tubes move in a right-and-left direction. A falling film heat exchanger installed in a ship, an offshore structure or the like can avoid reduction in heat exchange performance, even when the ship or the like inclines and swings, by substantially evenly distributing and dropping a liquid onto the crests of the tubes and causing the liquid dropped from the tubes located in an upper array to fall onto the tubes located in the next lower array.

Abstract: In a bubble lift system 10, a pressurized chamber 21 is provided at an upper end portion of a riser pipe 11, and applies a pressure to an upper portion inside the riser pipe 11 to suppress an increase in the volume ratio of bubbles to a fluid mixture rising inside the riser pipe 11 in a shallow water region. In this configuration, the upper end of the riser pipe 11 is not opened to the atmosphere but is inserted into the pressurized chamber 21 under a high pressure to thereby prevent expansion of the bubbles and gas. In addition, a deaerator 14 for discharging bubbles separated by a centrifugal force is also provided in a middle portion of the riser pipe 11 in a shallow water region to thereby make the bubbles distributed more evenly inside the whole riser pipe 11. Thus, provided are the bubble lift system 10 and a bubble lift method that are efficient and employable even in a deep water region.