| 摘要 |
PURPOSE:To measure the concentration of a waste liquid without any influence of fluctuations of the liquid level of the waste liquid, by measuring the circulated amount of the waste liquid in a forcible negative pressure circulation tye waste liquid concentrator. CONSTITUTION:A forcible negative pressure circulation type concentrator concentrates the waste liquid in a heating pipe 5 and a steam pipe 6 over forcible circulation by a circulating pump 7. A flow meter 9 is provided to a circulating loop to measure the flow rate continuously. The flow rate Q of the circulating pump and a lift H has the relation shown by the graph, so while a synchronous motor is employed as a circulating pump driving motor M, the rotational frequency of the pump is made constant to obtain the constant flow-rate-lift curve 4. As the waste liquid varies in concentration, the pressure drop of piping and equipment varies and resistance curves 1, 2, and 3 and the flow rate Q vary. For this purpose, the relation between the flow rate and concentration is found in advance and the actual flow rate is measured to measure the concentration without influence of fluidity of the waste liquid. |
