【Ten Years of Rapid Development in Chemical Processing Equipment】The first domestic chemical pulp alkali recovery system was put into operation successfully between 1652 and 2011

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Happy May Day 2024! Safety first. Let’s give praise and support to the achievements made in China’s chemical engineering technology and equipment. **********************【Ten Years of Progress in Chemical Engineering Equipment】A continuously updated summary post is available; feel free to join the discussions at https://bbs.hcbbs.com/thread-3576046-1-1.html (Source: Haichuan Chemical Industry Forum) ***************** In June 2011, China’s first chemical pulp alkali recovery system was put into operation – the first-phase chemical pulp production line of Guangxi Jingui Co., Ltd. As of last week, it had been in trial operation for nearly 100 days, with all economic and technical indicators meeting expectations. Once put into operation, this alkali recovery system, for which the investment exceeded 400 million yuan, raised Jinguì Company’s capabilities in papermaking chemicals and pollutant recovery to a leading level in China. 　　The test results show that the main pollutants after treatment by Jin Gui Company amount to only **11.25% of the standard value, which is better than the industry standards** ； At the time of discharge, the COD concentration is 60–80 ppm, while the BOD concentration is around 20 ppm. The amount of pulp wastewater discharged per ton is approximately 10 tons, all of which meet the discharge standards approved for this project; these values are far superior to those of other domestic pulp production lines that do not have alkali recovery systems in place. 　　This system sends the chemical pulp pulping wastewater to the alkali recovery workshop, where it is evaporated and concentrated before being sent to the alkali recovery furnace for combustion. After combustion, the organic substances in the wastewater are converted into thermal energy, while the alkalis present in the pollutants are recovered through a causticization process; this reduces the difficulty of treating these pollutants, thereby achieving energy savings, emission reduction, and clean production. Low-emission technologies for chemical mechanical pulp wastewater have been included in the **Ministry of Environmental Protection’s 2010 List of Environmental Protection Technologies Encouraged for Development**, becoming mature technologies for the control of pollutants generated by chemical pulp and chemical mechanical pulp processes that are encouraged for demonstration and widespread adoption. 　　It is understood that during the alkali recovery process, new chemical control agents cause the surfaces of some adhesives to become passivated or to be adsorbed, while other adhesives are emulsified and dispersed or degraded, thereby losing their adhesive properties. This technology can effectively treat the waste liquids generated during pulping and cooking in the paper industry, as well as recover the alkali used for cooking, thereby achieving comprehensive benefits such as resource recycling, energy savings, and reduced pollution. 　　To date, the system has operated stably during the trial production phase, with a white water reuse rate of 80%, a water recycling rate of 95%, and an alkali recovery rate from wastewater of 93%. The clean hot water recovered by the system is equivalent to saving approximately 33,000 tons of standard coal per year. 　　With the rapid development of industries such as printing and packaging, the pollutant components in waste paper are becoming increasingly complex, making it more difficult to remove or control them. As a result, researching and developing corresponding technologies and equipment has become an urgent task, and it is also a focus of attention for the paper chemicals industry. During the construction of this recycling facility, as production technology improved and environmental protection standards became stricter, Jin Gui Company promptly enhanced the design for pollutant treatment, thereby continuously improving the relevant technologies.