Steam radiator efficiency calculation and cleaning

- Nov 26, 2018-

Steam radiators are what we call heat exchangers. They are used in many industries such as petroleum, chemical, food, power and many other industries. Steam heat exchangers have energy saving and efficiency, improve heat transfer efficiency, reduce heat transfer area, and reduce Pressure drop, improve the thermal strength of the device and so on.


For the calculation method of steam radiator efficiency, many people do not understand, so that will affect the construction progress, then, how to calculate the efficiency of steam radiator?


Steam radiator efficiency overview


The steam radiator uses steam as a heat source to heat the water. The equipment that uses steam as a heat source to heat the water is divided into two categories: 1. Direct heating equipment - steam and water are directly mixed to heat the water. 2. Indirect heating equipment - steam and water are two independent systems that conduct heat from high grade to low grade through metal surface heat.


The hourly heat load is: 0.72*10000*(60-20)=288000KJ/h; hourly steam consumption: 288000/(2763-697)=139kg; heat exchanger average temperature difference: 164-40=124; heat exchange efficiency : 20W/m2 (assuming that the value is determined according to the type, arrangement, medium flow rate, etc. of the heat exchange tube. Please check the data according to the specific conditions); the minimum heat transfer area required: 288000/124/20*1000/ 3600 = 32 square meters.


According to the temperature difference between the refrigerant and the heat medium, the logarithmic mean temperature difference can be obtained; according to the physical property parameters of the heat medium (or refrigerant) and the temperature difference between the inlet and the outlet, the heat exchange power of the heat exchanger can be obtained, and the heat exchange power is the logarithmic mean temperature difference and heat transfer. The coefficient of the coefficient and the heat exchange area can be used to exchange heat exchange area.


Although the calculation method of the efficiency of the steam radiator is not complicated, it is necessary to know the knowledge of the efficiency of the steam radiator, so as to ensure the accuracy of the calculation value, avoid errors during construction, and affect the quality of the project. Come to serious consequences.


We know the calculation of the heat transfer efficiency of the steam radiator, so pay attention to the cleaning of the steam radiator during use.


In the chemical industry's production process, due to many reasons, steam radiator equipment and pipeline lines will produce many such as coking, oil, scale, scale, sediment, corrosion products, polymers, fungi, algae, sticky Dirt and other dirt. The dirt generated will invalidate the equipment and pipelines, and the equipment system will have a decline in production, energy consumption and material consumption. When the fouling is particularly serious, the process will be interrupted, and the system will be forced to stop production, directly causing various economics. Losses, and even malignant production accidents may occur.


It is almost impossible to completely avoid the generation of dirt in the development of science today. Therefore, the cleaning of equipment such as steam heat exchangers has become an indispensable part of industrial production, especially in the production of petrochemical and thermoelectric plants. .


Important steps for cleaning steam radiators


The first step: descaling cleaning. Proportionally add the descaling cleaning agent in the circulating water of the cleaning tank to carry out boiler cleaning and descaling. Determine the cleaning cycle time and the amount of the added agent according to the amount of the scale. Confirm that all the scale is cleaned and then transfer to the next cleaning procedure. .


The second step: clean water. After the cleaning equipment and the boiler are connected, it should be cleaned with clean water for 10 minutes to check the system status, whether there is any leakage, and the floating rust is washed away.


The third step: peel off the anti-corrosion cleaning. Proportionally add surface release agent and slow release agent to the circulating water of the cleaning tank, cycle cleaning for 20 minutes to separate the scale and cleaning parts, and pre-corrosion treatment on the surface of the object without scale to prevent descaling and cleaning. The cleaning agent corrodes the cleaning components.


The fourth step: passivation coating treatment. The passivation coating agent is added to passivate the boiler cleaning system to prevent corrosion of pipelines and components and new rust formation.


Steam radiators need to be scientifically cleaned, otherwise energy consumption and environmental damage may result, and equipment may be damaged while reducing operational efficiency. Both chemical cleaning and high-pressure water jet cleaning are effective. At present, all countries are making every effort to develop environmentally-friendly cleaning technology in order to reduce energy consumption and prevent excessive damage to the environment.