PROBLEM TO BE SOLVED: To provide a box-type vessel capable of maintaining an acid treatment liquid to a prescribed pH value.SOLUTION: Provided is a box-type vessel which includes an acid treatment tank for storing an acid treatment liquid and a pair of takeup rolls provided inside the acid treatment tank for taking up a laver net with attached laver. The box-type vessel includes: a pH sensor which is provided in the acid treatment tank for detecting pH of the acid treatment liquid an undiluted liquid discharge part for discharging an undiluted acid liquid, which is provided at a position not interfering with the laver net taken up by the takeup rolls and an undiluted liquid feeder which automatically adjusts a feeding amount of the undiluted acid liquid fed to the undiluted liquid discharge part based on the detection value of the pH sensor. The undiluted liquid discharge part is provided on an entering side of the laver net in the acid treatment tank.SELECTED DRAWING: Figure 3COPYRIGHT: (C)2018,JPO&INPIT【課題】酸処理液を所望のpH値に維持することが可能な箱型船を提供する。【解決手段】酸処理液を貯留する酸処理槽と、該酸処理槽内に設けられ、海苔が付着した海苔網を巻き取る一対の巻取ロールとを備える箱型船であって、酸処理槽に設けられ、酸処理液のpHを検出するpHセンサと、巻取ロールに巻き取られる海苔網と干渉しない位置に設けられ、酸原液を吐出する原液吐出部と、pHセンサの検出値に基づいて原液吐出部に供給する酸原液の供給量を自動調節する原液供給装置とを備え、原液吐出部は酸処理槽において海苔網の進入側に設けられている。【選択図】図3
