Laboratory peristaltic pump is a rapidly developing technology that is replacing complex and frequently maintained other positive displacement pumps in chemical dosing. Acids, alkalis, and solvents corrode the valves, seals, rotors, and moving parts of the diaphragm pump and single screw pump (two commonly used positive displacement pumps), resulting in pump damage, causing downtime, and increasing the cost of life cycle. In contrast, the working principle of the Laboratory peristaltic pump can reduce these costs and has no mechanical parts in the product line. When using the laboratory peristaltic pump, the fluid only contacts the inner wall of the hose or pipeline, and the cost of the pipe is very low, and it is very durable with less maintenance.
Laboratory peristaltic pumps have strong self-priming ability. The theoretical suction lift of water under one atmospheric pressure can reach 9.8 meters, but due to the resistance caused by the surface tension of the medium in the pipeline, the actual flow rate will decrease, and the flow rate will decrease by 15% for every one meter increase in suction lift. The suction lift is related to the pump head hose and medium of the Laboratory peristaltic pump. If a high suction lift is required, a thinner inner diameter and thicker wall hose can be selected, and a higher-speed driver can also be chosen.
The traditional liquid terminal filtration is mostly microfiltration, including the filtration form used for sterilization filtration. The flow direction of the liquid is consistent with the filtration direction. With the progress of filtration, the thickness of the filter layer or gel layer formed on the surface of the filtration membrane gradually increases, and the flow rate gradually decreases. When the filtration medium is an ultrafiltration membrane or a microfiltration membrane with a small pore size and the solid content in the material liquid is high, the dead-end filtration method is adopted, and the flow rate will rapidly decrease. Therefore, the dead-end filtration can only handle small volumes of material liquid.
For large-scale material liquid filtration, tangential flow filtration should be used, and the Laboratory peristaltic pump is used to transport the liquid. Shear forces are generated on the surface of the filtration medium during the flow process, which reduces the accumulation of the filter cake or gel layer and ensures a stable filtration speed. Therefore, tangential flow filtration is widely used in ultrafiltration and some microfiltration processes.