Sulfur Recovery Daily Question 2018.10.12
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Question: What are the important process parameters of heat exchangers? Answer: The quality of a heat exchanger is usually evaluated based on the overall heat transfer coefficient and the pressure drop. (1) The overall heat transfer coefficient KK = Q/SΔT, or Q = KSΔT. Where: Q – heat transfer rate, W ； S --- Heat transfer area, in m2; △tm --- Average temperature difference, in °C; K ---- Total heat transfer coefficient, in W/m2·°C. It can be seen that, for the same heat transfer area and average temperature difference, the larger the total heat transfer coefficient K, the greater the amount of heat Q transferred. In other words, for the same amount of heat to be transferred and the same average temperature difference, the larger the total heat transfer coefficient K, the smaller the heat transfer area required, which helps to reduce costs. (2) Pressure drop: The pressure drop in a heat exchanger is caused by two types of losses, namely frictional losses due to fluid flow and losses associated with changes in flow direction. Increasing the fluid velocity can enhance the heat transfer coefficient and reduce the required heat transfer area; however, this also leads to an increase in pressure drop. Generally, it is advisable to keep the pressure drops in both the tube side and shell side within the range of 0.034–0.17 MPa.
The quality of a heat exchanger is usually evaluated based on the overall heat transfer coefficient and the pressure drop. 1) The overall heat transfer coefficient K is given by K = Q/FΔT, or Q = KFΔT. Where: K is the overall heat transfer coefficient, in kcal/m²·hour·°F; Q is the heat load, in kcal/hour; F is the heat transfer area, in square meters; and ΔT is the average temperature difference across the heat exchanger, in degrees. It can be seen that, for a given heat transfer area and average temperature difference, the larger the overall heat transfer coefficient K, the greater the amount of heat transferred Q. In other words, for the same amount of heat to be transferred and the same average temperature difference, a higher overall heat transfer coefficient K means that a smaller heat transfer area is required, which helps to reduce costs. 2) Pressure drop: The pressure drop in a heat exchanger is caused by two types of losses, namely frictional losses due to flow and losses associated with changes in flow direction. Increasing the fluid velocity can enhance the heat transfer coefficient and reduce the required heat transfer area; however, this also leads to an increase in pressure drop. Generally, it is advisable to keep the pressure drops in both the tube side and shell side within the range of 0.034–0.17 MP
The quality of a heat exchanger is usually evaluated based on the overall heat transfer coefficient and the pressure drop. ?
Material selection for the cylinder, wall thickness, dimensions of the end caps, heat exchange within the heat exchanger, heat exchange area, pressure drop, and wall temperature of the heat exchanger (Force and Heide)
The quality of a heat exchanger is usually evaluated based on the overall heat transfer coefficient and the pressure drop. 1) Total heat transfer coefficient K: K = Q/FΔT or Q = KFΔT. Where: K is the total heat transfer coefficient, in kilocalories per square meter·hour·degree; Q is the heat load, in kilocalories per hour; F is the heat transfer area, in square meters; ΔT is the average temperature difference across the heat exchanger, in degrees. It can be seen that, at the same heat transfer area and average temperature difference, the larger the total heat transfer coefficient K, the greater the amount of heat transferred Q. In other words, for the same amount of heat to be transferred and the same average temperature difference, a larger total heat transfer coefficient K means that a smaller heat transfer area is required, which helps to reduce costs. 2) Pressure drop: The pressure drop in a heat exchanger is caused by two types of losses, namely frictional losses due to flow and losses associated with changes in flow direction. Increasing the fluid velocity can enhance the heat transfer coefficient and reduce the required heat transfer area; however, this also leads to an increase in pressure drop. Generally, it is advisable to keep the pressure drops in both the tube side and the shell side within the range of 0.034–0.17 MPa.
The quality of a heat exchanger is usually evaluated based on the overall heat transfer coefficient and the pressure drop: the overall heat transfer coefficient K = Q/Ft. It can be seen that, for a given heat transfer area F and average temperature difference Δt, the higher the overall heat transfer coefficient K, the greater the amount of heat transferred Q. In other words, for the same amount of heat to be transferred and the same average temperature difference, a higher overall heat transfer coefficient K means that a smaller heat transfer area is required. Pressure drop: The pressure drop in a heat exchanger is caused by two types of losses, namely frictional losses due to flow and losses associated with changes in flow direction. Increasing the fluid velocity can raise the heat transfer coefficient K and reduce the heat transfer area F. Generally, it is appropriate for the pressure drop in the tube side and shell side to be between 0.034 MPa and 0.17 MPa.
The quality of a heat exchanger is usually evaluated based on the overall heat transfer coefficient and the pressure drop.
The quality of a heat exchanger is usually evaluated based on the overall heat transfer coefficient and the pressure drop.
The quality of a heat exchanger is usually evaluated based on the overall heat transfer coefficient and the pressure drop. 1) Total heat transfer coefficient K: K = Q/FΔT or Q = KFΔT. Where: K is the total heat transfer coefficient, in kilocalories per square meter·hour·degree; Q is the heat load, in kilocalories per hour; F is the heat transfer area, in square meters; ΔT is the average temperature difference across the heat exchanger, in degrees. It can be seen that, at the same heat transfer area and average temperature difference, the larger the total heat transfer coefficient K, the greater the amount of heat transferred Q. In other words, for the same amount of heat to be transferred and the same average temperature difference, a larger total heat transfer coefficient K means that a smaller heat transfer area is required, which helps to reduce costs. 2) Pressure drop: The pressure drop in a heat exchanger is caused by two types of losses, namely frictional losses due to flow and losses associated with changes in flow direction. Increasing the fluid velocity can enhance the heat transfer coefficient and reduce the required heat transfer area; however, this also leads to an increase in pressure drop. Generally, it is advisable to keep the pressure drops in both the tube side and the shell side within the range of 0.034–0.17 MPa.
Material selection for the cylinder, wall thickness, dimensions of the end caps, heat exchange within the heat exchanger, heat exchange area, pressure drop, and wall temperature of the heat exchanger