Scaling in the low-temperature waste heat recovery unit of sulfuric acid plants severely affects steam production

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Whether sulfur is used to produce sulfuric acid or pyrite, sulfuric acid plants typically incorporate low-temperature waste heat recovery systems to capture heat for the generation of low-pressure steam, which is then used in subsequent processes or for power generation. However, for various reasons, the demineralized water preheater, deoxygenated water preheater, acid-acid heat exchanger, and evaporator in the system may all suffer from severe scaling, which leads to a decrease in the heat conversion efficiency of the low-temperature waste heat recovery unit, and consequently results in a reduction in the amount of steam produced by the unit. According to data from actual cases, steam production can decrease by as much as 40-50% due to severe scaling. For example, if a sulfuric acid plant’s low-temperature waste heat recovery system is designed to produce 200,000 tons of low-pressure steam per year, long-term scaling in the heat exchangers and evaporators may result in only around 100,000 tons of steam being produced in reality. This means that the low-temperature waste heat recovery system functions at only 50% of its capacity, and half of the substantial investment in such equipment is wasted. By employing advanced microwave scale inhibition technology, it is possible to effectively prevent scaling in the demineralized water preheater, deoxygenated water preheater, acid-to-acid heat exchanger, and evaporator in low-temperature waste heat recovery systems. This improves the heat exchange efficiency of these devices and increases the effective steam output of the system. After scale inhibition, the steam output of the plant can be increased through the following methods: (1) After scale inhibition, the heat exchange efficiency improves, which allows the temperature of the deionized water to be raised significantly; this in turn reduces the amount of steam needed for heating in the deaerator, thereby indirectly increasing the plant’s steam output. (2) The heat exchangers and evaporators no longer suffer from scaling, allowing more water to be heated in the same amount of time, thereby producing more steam. Practice has shown that it is entirely feasible to improve the thermal efficiency of heat exchangers by using advanced scale inhibition techniques such as microwave scale inhibition. Calculations show that by preventing scale formation, the amount of steam produced by the equipment can be significantly increased, thereby boosting the economic benefits of the enterprise. This leads to an increase in effective steam production of 50,000–60,000 tons per year, generating an economic value of 7–10 million yuan per year. Technical features of microwave scale inhibition and removal technology: 1. Wide range of scale inhibition types. It exhibits good scale-inhibiting effects on the vast majority of existing scales, including carbonate scale, sulfate scale, silica scale, oxalate scale, sodium chloride scale, hydroxide scale, and metal oxide scale. It can effectively prevent scaling on the feed side. 2. Strong scale inhibition capacity. It is not restricted by water quality and can handle high-hardness and high-alkalinity waters effectively. 3. No restrictions on pipe diameter or flow rate. It has strong adaptability and can handle tasks without any issues, regardless of the pipe diameter or flow rate. 4. Large scale and long distance. The device uses radio frequency antenna technology to transmit microwaves along water bodies and pipelines, enabling scale prevention and removal over distances of dozens or even hundreds of meters. 5. Low power consumption and maintenance-free. The device's power consumption ranges from 120 to 300 watts, making it low-power. The equipment can be installed without damaging existing facilities; it is simple to install and requires little maintenance over time. If you are interested, add me on WeChat: TigerPeng2014 or scan the QR code: https://p3-sign.toutiaoimg.com/tos-cn-i-6w9my0ksvp/cb2ad7cbeb5347a2b6625b9e789259e7~tplv-tt-origin-web:gif.jpeg?_iz=58558&from=article.pc_detail&lk3s=953192f4&x-expires=1733107143&x-signature=MZJXNGmpCybW6Vs1x32%2FeYXXGI8%3D