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“The pre-treatment technology for coal coking wastewater that enables efficient ammonia recovery was successfully evaluated as a scientific and technological achievement. Author/Source: Chuangju Technology; Date: 2021-09-13; Clicks: 54. On September 8, 2021, Tianjin Technology Property Rights Exchange Co., Ltd. organized experts to assess the scientific and technological achievement titled “Pre-treatment technology for coal coking wastewater that enables efficient ammonia recovery”, submitted by Tianjin Chuangju Technology Co., Ltd. The expert panel at the appraisal meeting listened carefully to the project report, and after posing questions and conducting thorough evaluations, it unanimously concluded that the project has reached an internationally advanced level overall. Introduction to this technical achievement: This achievement aims to develop a set of pre-treatment technologies for coal coking wastewater that enable the efficient recovery and utilization of ammonia, to improve the technical level of the associated equipment, particularly the performance of the equipment used inside towers, to ensure that the wastewater treatment standards are met, and thus to achieve efficient recovery of ammonia. I. Main Research Contents 1. Research on a new ammonia evaporation pretreatment process for coal coking wastewater in order to increase the ammonia concentration. Given that the traditional ammonia evaporation process can only produce ammonia water with a concentration of 8–10 (wt)%, and that increasing the ammonia concentration leads to equipment blockages and prevents the system from operating stably over long periods, this study analyzed the reasons for blockages in the process pipelines and equipment by taking into account the main components of coal coking wastewater. A new ammonia evaporation process was developed through process simulation; this process has both acid removal and ammonia removal functions, enabling the production of ammonia water with a concentration of 20 (wt)% or higher. 2. Research on a new type of anti-clogging tray technology to address the severe clogging problem in ammonia evaporation towers. In response to the serious clogging issue in the ammonia evaporation towers used for treating coal coking wastewater, the reasons why traditional bubble-type trays and ordinary vertical spray-type trays fail to prevent clogging were analyzed. A new type of anti-clogging tray was developed; this tray has no components that could lead to clogging in its structural design, and the high gas velocity at the tray openings makes clogging less likely. It offers excellent anti-clogging performance as well as high mass transfer efficiency. Professional fluid dynamics simulation software was used to conduct in-depth studies on the gas flow field, liquid flow field, and gas-liquid two-phase flow field of this tray, with the tray structure being optimized accordingly. Hydraulic tests on this tray were carried out using cold model experiments, providing a theoretical basis for tray design. 3. Research on a new type of baffle for side-stream ammonia extraction ports to address the serious problem of entrainment of mist during extraction. To tackle the issues of poor mist removal at side-stream ammonia extraction ports and the high water content in the extracted ammonia gas, which affects its concentration, a baffle was developed that effectively prevents mist entrainment while also possessing strong anti-clogging capabilities. Industrial applications have shown that this baffle for side-stream ammonia extraction ports yields remarkable results. 4. Research on efficient recovery and utilization technologies for concentrated ammonia water to reduce wastewater treatment costs in coal coking enterprises. Addressing the issue of fluid level rise in gas desulfurization systems due to the use of low-concentration ammonia water produced by traditional ammonia evaporation processes, the causes of this fluid level rise were analyzed; high-concentration ammonia water with a concentration of 20% (by weight) or higher, produced by new processes, was then used in gas desulfurization systems, thereby solving the problem of fluid level rise resulting from the addition of ammonia to the desulfurization solution. Furthermore, concentrated ammonia water can also be used for flue gas desulfurization or denitrification in power plants, enabling efficient recovery and comprehensive utilization of ammonia, turning waste into a resource and reducing the wastewater treatment costs for coal coking enterprises. II. Economic Benefits: Taking a coal coking production capacity of 1.2 million tons per year and a wastewater generation volume of 40 m3/h as examples, the various economic indicators for the traditional ammonia steaming process and the process based on this technological innovation are compared as follows: (1) Assuming the cost of steam is 150 yuan per ton, and with an annual operating time of 8,000 hours, the annual savings in steam-related costs amount to approximately (6.8–4.8) t/h × 8,000 h × 150 yuan/t = 2.4 million yuan. (2) The cost of treating the desulfurization liquid is calculated at 30 yuan per ton; thus, the annual savings in costs related to its treatment amount to approximately (1.75–0.7) tons/hour × 8000 hours × 30 yuan/ton = 252,000 yuan. (3) Concentrated ammonia water can be used for desulfurization and denitrification in power plants. The cost of purchasing ammonia water is calculated at 600 yuan per ton; thus, the annual savings in purchasing costs amount to approximately 0.7 t/h × 8000 h × 600 yuan/t = 3.36 million yuan. (4) Traditional ammonia vaporization methods require 1–3 months of maintenance due to blockage issues, whereas the equipment based on this technological advancement needs maintenance only once a year, saving approximately 45,000 yuan in maintenance costs. In summary, for a coal coking plant with a production capacity of 1.2 million tons per year, this technical solution can result in annual cost savings of over 6 million yuan compared to traditional ammonia steaming processes. The savings are significant in terms of steam consumption, the treatment of desulfurization liquid in the desulfurization unit, the purchase of concentrated ammonia water for flue gas desulfurization and denitrification, as well as equipment maintenance costs. To date, this technological achievement has been successfully applied in wastewater pretreatment projects at nearly a hundred coal coking enterprises in China, generating economic benefits worth over 100 million yuan. III. Social benefits: The wastewater treated using this technological solution not only creates favorable conditions for subsequent biochemical treatment and plays a crucial role in ensuring that the wastewater is discharged in compliance with standards, but it also enables efficient recovery and utilization of ammonia, turning waste into a valuable resource. This helps to reduce the operating costs of environmental protection projects that otherwise would require significant investment, thereby increasing the motivation for coal coking enterprises to carry out technical upgrades and improve their equipment. In the coming years, as resources in the coal coking industry continue to be integrated, this project will generate even greater economic and social value. It is believed that the promotion and application of this technological achievement will undoubtedly bring about a major innovation in the pretreatment technology for coal coking wastewater!