SOLUTION: There is provided a blood purification device which circulates a washing fluid to a closed circuit which is formed of: a draining passage 27 for connecting a dialysate collection passage 14 and a waste liquid passage 16； a measurement pump P5 for draining which is provided on the draining passage 27； a connection passage 5 for connecting a dialysate supply passage 13 and a dialysate collection passage 14； and a circulation passage 28 for connecting a water supply passage 15 and the waste liquid passage 16, for washing each passage by the washing fluid. The blood purification device further comprises determination means for determining that density of the washing fluid in the closed circuit is normal. In the blood purification device, first, a prescribed amount of a washing fluid liquid concentrate is drawn to the closed circuit and, in a state of stopping the measurement pump for draining, the washing fluid and the washing fluid liquid concentrate are circulated to the closed circuit. Then, when the determination means determines that density of the washing fluid in the closed circuit is normal, the washing fluid is made to circulate in the draining passage and the measurement pump for draining for washing.EFFECT: As an effect, occurrence of damage of a measurement pump due to a washing fluid liquid concentrate with high density can be prevented.SELECTED DRAWING: Figure 6COPYRIGHT: (C)2020,JPO&INPIT【解決手段】 透析液回収通路１４と排液通路１６とを接続する除水通路２７と、当該除水通路２７に設けた除水用計量ポンプＰ５とを備え、さらに透析液供給通路１３と透析液回収通路１４とを接続する接続通路５と、給水通路１５と排液通路１６とを接続する循環通路２８とによって形成した閉回路に洗浄液を流通させて上記洗浄液による各通路の洗浄を行う血液浄化装置に関する。 上記閉回路中の洗浄液の濃度が適正であることを判定する判定手段を備え、まず上記閉回路中に所定量の洗浄原液を引き込んだら、上記除水用計量ポンプを停止させた状態で上記閉回路に上記浄水と洗浄原液とを循環させる。 その後上記判定手段が上記閉回路中の洗浄液の濃度が適正であると判定したら、上記除水通路および除水用計量ポンプに洗浄液を流通させて洗浄を行う。【効果】 高濃度の洗浄原液による計量ポンプの損傷を防止することができる。【選択図】 図６
