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Due to its specific operating environment, the pulp pump has certain requirements regarding its structure and components; the following are the requirements for the structure and components of a pulp pump. 1. To prevent the impeller from getting clogged, it is generally designed as an open impeller, which also makes cleaning of KCB gear pumps easier. However, closed impellers can be used as well, provided that the flow channels inside the impeller are wide enough. 2. On the back side of the impeller, back vanes are installed to prevent pulp from entering the filler box. By the same principle, clean water is also injected into the sealing device. 3. The dimensions of the pump body must naturally be such that it is not blocked by pulp; larger holes are provided in various locations for cleaning, or a design is used that allows the end cover to be removed easily. The structure in front of the pump inlet should facilitate the flow of pulp into it. For this reason, the suction pipe of the high-temperature residue pump must be thick and short, and the liquid level in the suction-side tank should be kept as high as possible. The inlet of the main blade is twisted into a mixed-flow shape to facilitate the uptake of the incoming pulp. At high concentrations, there must be a water head of over 2 meters from the pump axis to the liquid suction level, and a booster impeller is installed in front of the main impeller. Requirements for the structure and installation of pulp pumps: 1. Since frictional losses in the pipes are high at high concentrations, it is necessary to minimize resistances such as bends and branches in the discharge pipes of gear pumps. 2. Stir the pulp slurry well, and use a gear oil pump with heat retention to ensure that it flows as evenly as possible to the pump’s inlet. 3. It is very important to remove as much air as possible from the pulp before it enters the impeller, because a centrifugal pump experiences a sharp decline in performance when liquid containing air is pumped. Furthermore, the retention of air can cause unstable operation of the pump; therefore, it goes without saying that a structure should be adopted to prevent air from remaining inside the pump. The above are the main considerations for pulp pumps. Air forms bubbles in the pulp and enters between the fibers; at high concentrations, since the fiber filaments are closely packed together, although stirring can move the bubbles away from a fiber, it is difficult to get them to reach the free surface. For this reason, air has become the biggest obstacle preventing the improvement in the performance of high-concentration pulp centrifugal pumps for asphalt insulation. The measures taken for this purpose are to install mixers and crushers on the suction side to expel the free air through vertically installed exhaust pipes, but it cannot be expected that all of it will be removed. The design of the Ariachama company’s models in the United States features a large feed tank on the suction side of the pump; within this spacious tank, the pulp is fed into the pump’s suction inlet by a feeder, which simultaneously removes air from it. Using this method, slurries with a concentration of around 8% can be pumped.