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In the field of coal chemical industry, olefin separation units play a crucial bridging role and are key equipment for the success of coal-to-olefins projects. The product gas from the MTO unit, after being compressed in the second stage by the product gas compressor, enters a water scrubber to remove any entrained oxides, and then goes into an alkali scrubber where strong alkalis are used to eliminate any acidic gases carried along. Washing and alkali washing are pre-treatment processes for the product gas before it enters the distillation system; they help to prevent substances such as polymers and dry ice from clogging the distillation system or contaminating the product. The Shenhua Baotou coal-to-olefins project has a capacity of 1.8 million tons per year for coal-to-methanol production, 600,000 tons per year for methanol-to-olefins production, 300,000 tons per year for polyethylene production, and 300,000 tons per year for polypropylene production. The separation technology for the alkali washing system in the MTO unit employs the Lummus process from the United States. From the time the unit began operating until 2014, its shutdown for maintenance was carried out once a year. In order to maximize economic benefits, the planned maintenance period for the Shenhua Baotou MTO unit in 2015 was set at one and a half years; the scheduled maintenance date was April 1, 2016. However, by December 2015, severe blockages had occurred in the strong-alkali section of the alkali washing tower, as well as in the downcomers. The ability of the tower trays to facilitate liquid flow decreased steadily. Due to this declining capacity in the strong-alkali section, it became necessary to reduce the circulation volume in that section as well, in order to prevent the accumulation of alkaline solution on the tray surfaces. As of February 3, 2016, the circulation rate in the strong alkali section had been reduced from 60 t/h to 4.5 t/h, while the pressure difference in that section increased from 10 KPa to 21 KPa ； When the circulation rate in the medium-alkaline section was 60 t/h, the pressure difference rose to a maximum of 18 KPa; even after reducing the circulation rate to 55 t/h, the pressure difference still reached 13.7 KPa ； The circulation rate in the weakly alkaline section can still be maintained at 60 t/h, but the pressure difference also increases from 10 kPa to 13.8 kPa. After blockage occurred in the caustic scrubber tower, the plant tried various methods such as increasing the dosage of butter inhibitor, reducing the alkali concentration in the scrubber tower, carrying out segmented hot water flushing, and using xylene for washing, but none of these methods proved effective. Before trying the alkali scrubber cleaner, the strong-alkali section was already unable to circulate effectively, and the medium-alkali section also showed significant blockages, with a tendency for the situation to worsen, severely affecting the normal operation of the plant. Experts in cleaning alkali scrubber towers – RedSain’s alkali scrubber tower cleaner enables online cleaning. In response to this issue, Tianjin RedSain New Material Development Co., Ltd. has developed, based on the characteristics of petrochemical and coal chemical industries, a patented product called TRD-1F Alkali Scrubber Tower Cleaner. This cleaner not only helps to prevent the formation of butter during the alkali cleaning process but also contains efficient dispersing components that enable the removal and dispersion of polymers adhering to the tower trays; these polymers are then removed along with the waste alkaline solution, thereby restoring the cleaning efficiency of the alkali scrubber tower. This allows for online cleaning of towers that have suffered from blockages, thus extending the operational lifespan of the equipment. “Expert” cleaning process: RedSain Corporation conducted technical exchanges regarding this product with Shenhua Baotou Company, and was invited to carry out experiments using the detergent produced by our company for cleaning alkali scrubbers. The experimental results showed that this detergent is effective at dispersing the butter that forms inside alkali scrubbers, and it received unanimous approval from Baotou Company. Therefore, in order to prevent further deterioration of blockages in the alkali scrubber towers, from February 3, 2016, to March 2, 2016, the Shenhua Baotou Olefins Plant used our company’s alkali scrubber tower cleaning agent for online cleaning. The test was carried out in two phases. In the first phase, the weakly alkaline section and the moderately alkaline section were cleaned; larger amounts of caustic cleaner were injected into these sections to gradually remove the grease from the tray surfaces, and the cleaning effect was observed ； In the second phase, emphasis is placed on cleaning the strong-alkali section; the amount of cleaner injected into this section is increased, while the amounts injected into the medium-alkali and weak-alkali sections are reduced. The trays are cleaned from bottom to top to prevent a large amount of butter on the trays in the strong alkali section from falling off and accumulating together with the butter attached to the lower trays. Cleaning effect: During the trial use of the alkali scrubber cleaner TRD-1F, the circulation volume in each alkali section increased, while the pressure differences across the various sections of the alkali scrubber remained stable or even decreased. This significantly improved the operation of the facility and ensured its proper functioning ； Especially in the strong alkali section, the circulation rate was gradually increased from 4.5 t/h to 22 t/h, while the pressure difference dropped from around 20 KPa to around 19 KPa. The maximum circulation rate of the alkaline solution in this section kept increasing; both the pressure difference and the liquid level remained stable, with no occurrence of liquid carryover. This fully demonstrates the cleaning effect of the detergent used in the caustic scrubber tower. The following shows the changes in the state of the butter in the spent alkaline solution: before using the cleaning agent, the butter in the spent alkaline solution was dark red in color, paste-like in texture, highly viscous, and had poor flowability ； During the trial period of the cleaner, the waste alkaline solution had a bright red butter-like color and was slightly foamy; after being left to stand, an oil layer with good fluidity formed ； Even after the use of the cleaner was completed, it continued to exert its effect; the amount of butter in the waste alkaline solution decreased significantly, and its color lightened. In summary, after one month of using this cleaner for cleaning the alkaline scrubber towers, the operational conditions of Shenhua Baotou’s alkaline scrubber towers improved markedly. Tianjin Ruide Saien New Material Development Co., Ltd., thanks to the excellent ability of its TRD-1F alkaline scrubber tower cleaner to prevent the formation of butter and to remove existing amounts of butter, was able to resolve the problem of blockages in Shenhua Baotou’s MTO plant’s alkaline scrubber towers by enabling online cleaning of these blocked towers. This ensured the safe, efficient, stable, and optimal operation of the MTO plant. As a leading expert in alkaline scrubber tower cleaning in the industry, Tianjin Ruide Saien New Material Development Co., Ltd. has received high praise from Shenhua Baotou Company for the effectiveness of its products and technical services, thereby generating significant economic benefits for its clients.