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Basic data ☆ Ammonia treatment capacity: 5 t/h ☆ Composition of ammonia water (wt): NH3: 8.5% (100 wt%), H2O: 90.5%, CO2: 1.0% II. Process flow description 1. Brief description of the process flow: The incoming ammonia water and the waste liquid from the tower bottom are heated through a feed preheater to around 90°C, after which they enter the ammonia distillation tower operating at a pressure of approximately 0.12 MPa (A). Steam is used for stripping and distillation; the ammonia vapor exiting the ammonia condenser at the top of the tower (at around 70°C) enters a high-position ammonia absorber for absorption. The liquid phase obtained from the condensation in the ammonia condenser is directly fed back into the tower as reflux. 2. Process flow description: ☆ The heating method for the tower and reactor can be direct steam or indirect steam (reboiler). Compared to indirect steam heating, direct steam heating results in more wastewater, fewer pieces of equipment, and a shorter process flow ； ☆The temperature of ammonia entering the high-position ammonia absorber at 70℃ is relatively high; an additional heat exchanger can be added, depending on the area of the cold exhaust surface. III. Design Scheme 1. The ammonia vaporization tower adopts an internal recirculation configuration with an ammonia fractionator located at the top of the tower: the tower diameter is Φ800mm, and the tower height is approximately 15.0m (including about 2m for the skirt) ； The number of tray layers is 24, with a tray spacing of *** mm ； Tower internals type: Radial side-guided spray tray (CJST) ； Material: The tower and its internal components are made of stainless steel 304, while the skirt is made of carbon steel. 2. The ammonia fractionator uses a stainless steel spiral plate heat exchanger, with a heat exchange area of F=---m2. IV. Meeting of process specifications ☆ Ammonia content in the gas at the top of the tower: ≥65% (Wt) ☆ Composition of the liquid at the bottom of the tower: NH3 ≤ 150 ppm ☆ Direct steam consumption: ≤200 kg/m3 of feed ammonia water. V. Technical advantages of the CJST stainless-steel ammonia evaporation tower 1. Introduction to CJST trays The radial side-guided jet tray CJST is a new type of spatial mass transfer tray developed by our company based on earlier research results regarding vertical sieve tray towers. It represents our company’s proprietary technology, and a patent has been granted for it; the patent number is: ZL 2006 2 0025314.8. This tray tower boasts advantages such as high mass transfer efficiency, large processing capacity, good operational flexibility, strong resistance to clogging, and ease of maintenance. It has been successfully applied in industries such as coking, chlor-alkali, fertilizers, petrochemicals, and fine chemicals, making significant contributions to enterprises’ capacity expansion, energy savings, and cost reduction, while also delivering excellent social and economic benefits. The CJST tray was listed as a project under the science and technology development plan by the Tianjin Science and Technology Commission in 2005, and in the same year it received grant funding from the **Technology Innovation Fund for Small and Medium-sized Science and Technology Enterprises. 2. Problems with traditional ammonia vaporization towers Traditional ammonia vaporization towers are generally of either bubble cap or grid plate type, and are made of cast iron. A bubble column is equipped with 30 or more trays, while a trayed column has 32 or more trays. Its problems: it requires a concrete frame, involves high costs, and has a long construction period ； Bubble column towers have a low processing capacity and efficiency, while tray columns are even less efficient, with efficiency generally only reaching 30% ； Ammonia water contains substances such as tar residues; in bubble-type mass transfer towers, the bubbles tend to get clogged ； High steam consumption and high operating costs. 3. Features of the CJST stainless steel ammonia evaporation tower: High efficiency – The CJST ammonia evaporation tower is equipped with 20–26 trays; the ammonia vapor concentration at the top of the tower can exceed 15%, while the ammonia content in the wastewater at the bottom is less than 150 mg/l. The ammonia evaporation rate reaches 98% (whereas traditional ammonia evaporation towers achieve a rate of less than 90%) ； Save over 30% on steam usage ； Anti-clogging, long operating cycle, easy maintenance and installation ； The total investment in equipment and civil works saves more than 30% compared to cast iron towers (by eliminating the need for a concrete frame). Ø Low operating costs: Energy savings in the ammonia vaporization tower are very important; if the steam consumption per ton of ammonia water is reduced by 30%, that amounts to approximately 60 kg of steam. Based on the processing of 300,000 tons of ammonia per year, 18,000 tons of steam can be saved, worth approximately 2.7 million yuan (at a cost of 150 yuan per ton of steam).