High-throughput tube, high-throughput tube heat exchanger, overview

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This post was last edited by gn_1984 on 2015-8-19 17:13. High-flux tubes and heat exchangers: High-flux tubes are new products that combine sintering methods with machining techniques; they enable an increase in the heat transfer coefficients on both the inner and outer sides of the heat exchange tubes, thereby significantly raising the overall heat transfer coefficient of the entire tube, that is, its total heat exchange efficiency. Thus, it addresses the current bottleneck issue in enhanced heat transfer processes, where only the heat transfer coefficient on one side is improved while the overall heat exchange efficiency remains low, thereby significantly enhancing the heat exchange efficiency of heat exchange tubes and heat exchangers. High-throughput tubes can reduce steam demand on the one hand, and improve heat transfer capacity on the other. In large heat exchange systems, the requirement for small temperature differences leads to a very high need for reboilers. Using high-throughput tubes at this time can reduce the number of reboilers by 3/4, with a required temperature difference ΔT of only 5°C. Replacing traditional light tubes with high-throughput tubes eliminates heat transfer bottlenecks, meets the demands of higher heat transfer loads, and significantly increases productivity. At the same time, while maintaining design efficiency, a lower steam pressure can be used to reduce cost expenditures. The currently established product designs include: porous layer sintered on the outer surface/low fins on the inner surface, longitudinal grooves on the outer surface/porous layer sintered on the inner surface, serrated surface on the outer surface/porous layer sintered on the inner surface, and fins on the outer surface/porous layer sintered on the inner surface. 1.1 Material and dimensions of high-flow tubes: Materials include carbon steel, white brass, stainless steel, red copper, and brass, etc. Dimensions: outer diameter of 15–40 mm, length of 500–12,000 mm. Generally, the middle part of the high-flow heat exchange tubes is a reinforced section, while the two ends are smooth sections to facilitate tube insertion and expansion jointing. High-throughput heat exchange tubes can be customized according to customer requirements. The products are packaged in wooden boxes. 1.2 The media suitable for high-flow heat exchangers include ethylene glycol (MEG), diethylene glycol (DEG, diglycol), trichloroethylene, ethane, propylene, and ethanol. 1.3 Applications of high-flux heat exchangers High-flux tubes and their associated high-flux heat exchangers can be used in various heat exchange devices involving phase changes, such as vaporizers, evaporators, reboilers, and condensers. Specific examples include ethylene vaporizers, the top condensers and reboilers in ethylene separation units, ethylene glycol evaporation systems, aromatic compound processing plants, and the main condenser-evaporators in air separation units. As well as natural gas liquefaction, cryogenic refrigeration, air separation, seawater desalination, etc. (1) Refining and petrochemical units such as the top condensers and reboilers of ethylene separation units, ethylene vaporizers, catalytic slurry evaporators, ethanol evaporators, ethylene glycol evaporators, etc., can reduce the heat exchanger area by over 80%, while also decreasing the horsepower required for refrigeration machines. Porous surfaces that enhance boiling heat transfer maintain stable performance during long-term operation, without any occurrence of coking or scaling. At the same time, it can significantly reduce the consumption of heat source medium, and even lower its temperature. (2) Natural gas purification and separation units, such as the reboiler condensers in low-temperature air separation plants, can on the one hand reduce the initial cost of evaporation-condensation (cooling) heat exchangers by reducing their area ； On the other hand, operating at a low temperature difference reduces power consumption. (3) Seawater desalination and waste heat utilization. 1.4 Benefit analysis of high-flow heat exchangers: The total investment for building a set of large-scale ethylene production equipment with a capacity of millions of tons is generally over 20 billion yuan. Based on historical data, heat exchanger costs account for around 30% of the total investment; therefore, the cost of heat exchangers for each such large-scale ethylene project amounts to approximately 7 billion yuan. However, since China’s energy utilization efficiency is only 34%, it is equivalent to the level of developed countries 20 years ago, and 10 percentage points lower than that of developed countries. Developing an efficient heat exchanger that can transfer more heat with the smallest possible temperature difference and minimal heat transfer area can be considered the first step in industrial energy-saving efforts. Using high-throughput heat exchange tubes and their efficient heat exchangers is the most effective and economical way to improve energy efficiency. At present, the demand for high-flow heat exchange tubes in our country is increasing sharply. High-flow heat exchange tubes and the efficient heat exchangers they enable have broad application prospects in industries such as the ethylene industry due to their excellent heat transfer properties, thus presenting a huge potential market demand. In countries such as the United States, Japan, and Germany, large-scale production of such high-efficiency heat exchange tubes as finished products has already taken place, but this technology remains a secret from our country; as a result, the ethylene industry is forced to use imported high-flux heat exchange tubes. The double-sided reinforced high-throughput tubes we have developed can not only reduce the heat transfer area and size of traditional heat exchangers by about 80%. Moreover, for large reboiler projects, it is also possible to reduce the total number of heat exchangers, thereby saving costs related to piping, control systems, foundation construction, and floor space. For the expansion and renovation of heat exchange units in existing plants, only the tube bundles need to be replaced, while the existing end caps, shells, pipelines, etc. can be reused.