How to choose the insulation method for asphalt tanks
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Currently, a 10,000 m3 asphalt tank is being constructed, equipped with coiled tubes, with the requirement that the temperature of the asphalt be maintained at around 140°C. Two insulation methods have been considered: 1) insulation using heat transfer oil, and 2) insulation using saturated steam at a pressure of 1.0–1.5 Mpa. Question: Which of the two methods has lower operating costs? Better cost-effectiveness? If heat is retained using steam, how is the condensate usually handled?
Liaohe Petrochemical Company is the largest asphalt production base in China, with an annual output of around 1.2 million tons of asphalt. The high output of asphalt has brought considerable economic benefits to the company. However, the storage of asphalt also consumes a large amount of steam each year. To further advance energy-saving efforts, the company focused on the energy consumption of the asphalt tank farm. Starting in mid-May, a project was carried out to upgrade the heating system in the asphalt storage area, switching from steam heating to heat transfer oil heating for the stored asphalt. After the renovation, 80,000 tons of steam can be saved each year, generating an economic benefit of 8 million yuan. By mid-June, half of the work related to laying the main pipelines for this project had been completed. Liaohé Petrochemical has a storage capacity of 146,000 cubic meters for asphalt; storing asphalt on an annual basis requires the use of over 200,000 tons of steam. At a cost of 100 yuan per ton of steam, the company spends around 20 million yuan each year on steam costs. Because asphalt is different from other light oils, its fluidity is poor at low temperatures, which makes it difficult to load and transport. In the past, steam was used to heat the asphalt, raising its storage temperature to 130°C–140°C. Moreover, every winter, even when there is no asphalt in the storage tanks, steam must still be used for heating to prevent the heaters from freezing. The vapor after heating is volatile; only a very small portion condenses into water for reuse, while the majority is released into the air, resulting in unnecessary waste. Using heat transfer oil for heating not only saves steam but also allows the oil to be reused, thereby achieving further energy savings. In addition, it improves operational flexibility by changing from continuous heating to intermittent heating; especially in winter, it can be turned off at any time, eliminating the concern that the heater might get damaged due to freezing. It is reported that the project is expected to be completed by the National Day holiday. (Reporter: Xu Pingping) Source: Liaohe Petrochemical Company Website, July 1, 2008
It is recommended to use heat transfer oil. The price of steam is too high nowadays; as the cost of coal continues to rise, the production costs of steam are also increasing steadily. Heat transfer oil can be reused, eliminating the issue of condensate recovery.
We use heat transfer oil, and it has been in use for 8 years (with intermittent operation); the quality of the heat transfer oil remains excellent
Agreeing to use heat transfer oil for heating asphalt is beneficial for three reasons: it is environmentally friendly, energy-efficient, and facilitates management. Currently, the heating method used by foreign companies also relies on organic heat carriers.
Heat transfer oil – pollution-free, high heat exchange efficiency, and energy-saving: lol
Could colleagues provide information on the design and process for heating with heat transfer oil?
I agree to use heat transfer oil; however, if heat transfer paste is added, the heat transfer efficiency will be better and energy consumption will be reduced.