Xinghua United Alkali Center: Precision management to achieve ‘zero emissions’ in the region”

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Xinghua Union Alkali Center: Precise Management Achieves Regional “Zero Emissions” Author/Source: Xinghua Group Date: 2021-12-16 Clicks: 3 Since the beginning of this year, the Union Alkali Center has implemented the company’s philosophy of precise management; through careful operation by its employees, technical limitations of the production facilities have been overcome. The purity of the soda ash produced can be maintained at 0.7% or lower on a long-term basis, and over 80% of the alkali produced is of top quality. While producing high-quality products with low salt and alkalinity over long periods, it is possible to keep the total amount of such products at a minimal level. Meanwhile, wastewater generated from rainwater utilization and equipment cleaning is continuously utilized, enabling a sustainable cycle of \"producing and using wastewater internally\". The current level of water in the wastewater tank has dropped from the upper limit of 5.5 m to 2.5 m, with over 3,000 cubic meters of wastewater having been used in production. A good operational condition of the process is the result of the concerted efforts of all employees at the caustic soda production facility, and it is the outcome of continuous and meticulous management. Process control to reduce water usage: To address issues such as mother liquor expansion and rising liquid levels in wastewater tanks that plague the production of high-purity soda ash and heavy soda ash at Taiwan Glass, the center clarified its approach by focusing on process optimization, strictly controlling the parameters of the carbonation reaction, and thereby reducing water usage. Through experimentation and discussion, the center carried out a series of technical modifications, adding wash water flow meters; by comparing various factors it determined the relationship between the amount of wash water used, the volume of gas used in the process, and the salt content of the product, and developed a detailed chart showing the appropriate amounts of wash water to use. The nozzles of the alkali filtration machine were modified to ensure effective penetration washing by the washing water. Regularly check for wear on the nozzles, adjust their height, and optimize the control of the contact area between the washing water and the alkali cake, thereby reducing the amount of water used unnecessarily. The staff on duty have received training and adhere strictly to the procedures, carrying out operations carefully in accordance with the standards. This approach enables continuous reduction of salt content while maintaining extremely high levels of fixed ammonia, thus ensuring normal production of ammonium chloride and laying the foundation for further reduction in the overall system volume. Precise management and scientific utilization of wastewater: The 6 Ammonia Scrubbing Units currently in operation generate 80 cubic meters of ammonia-containing wastewater per day. This large volume of wastewater places considerable strain on the sewage tanks at the caustic soda production facility. Such ammonia-containing wastewater cannot be discharged outside, so it must be utilized internally. Based on the test results of the Ammonia in Air systems and various exhaust outlets, different water replacement cycles were established for each such system. Water replacement was carried out at staggered times, and the water from one of the washing systems was used directly as a solvent for ammonium chloride, thereby reducing the discharge of ammonia-containing wastewater and lessening the pressure on the sewage tanks at the caustic soda plant. Thanks to the preliminary modifications and process optimizations, the overall system volume has been reduced; as a result, around 200 cubic meters of water can be pumped out of the wastewater tanks each day. Through proper control, the wastewater tanks at the caustic soda production facility now have sufficient space for emergency situations, ensuring \"zero emissions\" in that area. Through cyclic management and multi-party control of wastewater, a stable operational condition is achieved. This is thanks to the attention paid by the company’s leadership, as well as the collective efforts of all employees at the center. By expanding the capacity of the ammonium chloride E centrifuges and improving their maintenance, while strictly controlling the number of times they are used, monitoring oil temperature and vibration levels, and making frequent adjustments to the process, it is possible to ensure the long-term stable operation of these centrifuges. The water within the system is removed as effectively as possible through the use of wet ammonium, thereby reducing the total amount of water in the system. Production management is comprehensive in nature; maintaining a healthy operational status is also the best way to control wastewater. By paying close attention to on-site environmental management, process stability is ensured, leaks are reduced, the environmental conditions improve, and cleanliness is maintained. Strict controls are imposed on practices such as using water unnecessarily for cleaning or leaving water running, which helps to significantly reduce wastewater generation.