Calculation of the maximum condensation capacity of factory condensers
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I want to calculate the maximum condensation capacity of the shell-and-tube condenser located above the reaction vessel. The temperature and pressure of the steam are known, as well as the fact that it flows through the shell side; the chilled water temperature is 7 degrees Celsius. There is no flow meter available, only a pipe diameter of DN50, with the fluid flowing through the tube side. Guys, how should we estimate this situation? The flow rate of the chilled water is unknown, and the outlet temperature is unknown. Thank you
This post was last edited by bfdlwolf on 2018-11-7 at 11:51. The flow rate of the chilled water can be estimated based on the flow velocity and pipe diameter, while the heat load of the condenser can be calculated using the temperature difference of the chilled water entering and leaving the condenser as well as the specific heat capacity of the chilled water.
But how is the flow rate determined? The outlet temperature of the chilled water is unknown
The \"Guidelines for the Selection of Pipe Diameters in Process Units of Petrochemical Enterprises\" (SHT 3035-2007) or other documents such as the Regulations for the Process Design of Pipeline Systems (QSH0700-2008) (available in the thread) can be used to determine the flow velocity. The outlet temperature of the chilled water can be measured on-site or obtained from the data sheet of the chiller unit.
The selection guidelines provide a range, and it should be the flow rate of the main pipe. Since my chilled water system consists of many branches, is the flow rate also determined according to the regulations set here? It must be quite different from the actual value, right? The key issue is that our pipelines are very old, and there are no flow meters or thermometers.
This post was last edited by bfdlwolf on 2018-11-7 at 15:05. It’s just an estimate anyway, and what you requested is also the maximum condensation capacity. Also, it’s a pity you don’t know the amount of steam used
If estimation is used, it’s actually not difficult. For chilled water, the inlet temperature is known to be 7 degrees; the outlet temperature can be determined using a thermometer or temperature gauge (thus the temperature difference can be calculated). For a DN50 = 2” pipeline, assuming a flow rate of 1.3 M/S, the mass flow rate can be determined. The specific heat capacity can be found by consulting tables. With this information, the cooling load can be calculated. ------------------------------------------------------------------------------- As for steam, the flow rate is unknown; the temperatures at the inlet and outlet of the heat exchanger should be measured using a thermometer. The specific heat capacity can be found in relevant data, which then allows the flow rate to be determined... ------------------------------------------------------------------------------- What I want to ask is: since chilled water is generally cleaner, why isn’t it passed through the shell side while steam is passed through that side? This is because condensation of steam may lead to issues such as aggregation or sedimentation, and using the shell side for steam could cause problems... ------------------------------------------------------------------------------- The above information is provided for reference only