How is the size of the circulator in the syngas hydrate plant chosen?

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How is the size of the circulator in the syngas hydrate plant chosen? After the process flow is determined, consideration should be given to selecting a circulation pump. It is necessary to take into account the volume of circulation required to achieve the maximum methanol production during normal operation; for example, in Process 1, the circulation volume should be 16,000 Nm3/h. At a pressure of 13.0 Mpa, this corresponds to 16,000 ÷ (130 × 60) = 2.05 m3/min. When choosing a circulation pump, not only the requirements during normal operation need to be considered, but also those related to having a backup unit. If the circulation volume is at its maximum level and the pump fails at that time, and there is no backup unit available, it may not be possible to address the issue in time, resulting in the catalyst being damaged and becoming inactive. Additionally, the requirements for heating and reducing the catalyst must also be considered. Generally, an empty space velocity of 3000–5000 h-1 is considered during reduction. If the pressure during reduction is 5 Mpa, then the circulation rate required is: take an empty space velocity of 3000 h-1 ； The circulation volume should be: 3000×4.0=12000 Nm3/h; 12000÷(60×50)=4 m3/min. Therefore, for Process 1, a capacity of 2–2.2 m3/min is appropriate, with two circulation units – one in operation and one as a backup – and both units being used simultaneously during reduction. In processes two and three, the circulation volume should be: 21000; 21000÷(130×50) = 2.7 m3/min. During reduction, it should be: 4.5×3000 = 13500; 13500÷(60×50) = 4.5 m3/min. It can therefore be seen that two circulation pumps with a capacity of 2.7–3.0 m3/h should be used. During reduction, both units are operated simultaneously, resulting in a higher space velocity and a reduced reduction time.