The Sanyou Chlor-Alkali project has successfully “integrated” soda ash production
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This post was last edited by sunjl1981 on January 6, 2013, at 21:57. The Sanyou Chlor-Alkali project has successfully integrated soda ash production. June 12, 2012, 09:11. Source: On June 8, the first phase of the technical renovation project at Sanyou Group—involving a production capacity of 400,000 tons per year of polyvinyl chloride (PVC) and 500,000 tons per year of caustic soda—was successfully commissioned and put into operation. Thus, the first domestic circular economy industrial chain encompassing soda ash, chlor-alkali, chemical fibers, and silicon industry has taken shape within this company. The successful completion and commissioning of this project have met the needs of Sanyou Group for mutual supply of products among its soda ash, chemical fiber, and silicon industries’ production lines, as well as for the comprehensive utilization of waste. According to reports, the total investment in this project is 497 million yuan. Based on partial capacity expansion modifications to the existing production system, it will enable the plant to produce 400,000 tons of PVC and 500,000 tons of caustic soda per year. In line with the strategy of technological leadership, this project utilizes a number of internationally and domestically advanced new technologies and equipment, including a high-current-density naturally circulating bipolar zero-gap ion-exchange membrane electrolyzer, a new type of steam synthesis furnace, energy-saving fluidized bed drying technology, and a 106-cubic-meter large-scale polymerization reactor. These innovations have effectively reduced production costs; it is expected to generate annual benefits worth 36 million yuan. For every ton of polyvinyl chloride produced in a chlor-alkali plant, 1.59 tons of calcium carbide slag are generated. If this slag is simply stockpiled, it not only occupies a large amount of land but also causes pollution to the surrounding environment. Sanyou utilizes all the wet calcium carbide slag generated during the PVC production process to replace lime milk in both the ammonia stripping system for soda ash production and the chemical fiber wastewater treatment facility, generating economic benefits of over 10 million yuan annually. It not only reduces the costs of lime production and calcium carbide slag treatment, but also prevents environmental pollution caused by the storage of calcium carbide slag, thus enabling the recycling of waste residues and effluents. The dilute brine generated by this caustic soda plant is sent to the company’s internal soda ash plant as a raw material, which helps save a large amount of raw salt and reduces both construction investment and raw material costs. In addition, the produced caustic soda also met the raw material requirements of chemical fiber and silica fume production facilities. The produced chlorine and hydrogen chloride can be integrated with the company’s existing silicone production facilities, thereby achieving a complete balance between chlorine and hydrogen chloride and preventing potential environmental safety hazards caused by storage overload. Currently, the project has been designated by Hebei Province as a key circular economy construction project. hcbbs!!. hcbbs
Calcium carbide slag could otherwise be used to produce building materials such as cement. However, when used for ammonia stripping, it can only reduce the amount of slag produced; it cannot eliminate it entirely. Given that this slag contains sodium chloride, it likely has no practical use at all. Moreover, the process generates large quantities of calcium chloride-containing waste liquid. It remains unclear what happens to these residues and waste liquids—how can this possibly be considered a circular economy? ?
Partially agree with you. Waste calcium chloride solution can be concentrated to extract calcium chloride—a key component of de-icing agents. It can be directly used for removing ice and snow from highways, or as an additive in grass de-icing agents. As for Solvay's alkali residue, it can be used as reclamation materials, building materials and masonry raw materials, but you are right, the trouble in the White Sea can be eliminated temporarily.
Calcium solution is generally discharged directly into the sea. Concentration? So, how much does it cost to concentrate calcium at such a low concentration?
Wow, how do salt fields produce salt?! ! ! ………………………………………………? ? ?
Calcium chloride is not sodium chloride; it can’t be dried out by sun exposure. Through sun drying alone, only concentration can be achieved; to produce calcium, an evaporation system is required. The cost of this calcium production method is simply not competitive, and there isn’t a large market for calcium chloride either.