Integrated technology for capturing and mineralizing carbon dioxide

Abstract

The invention relates to an integrated technology for capturing and mineralizing carbon dioxide, which is characterized in that renewable ammonium salt (NH4HSO4) is used for obtaining a calcium and magnesium ions-containing leachate from ores or solid wastes, the leached residual slag is a small-size particle with high content of silicon oxide, the leachate is subjected to separation, impurities removal and precious metal purification, partial solution is directly used for capturing renewable ammonia gas to obtain a calcium and magnesium containing ammonia-rich liquid, CO2 is captured by the ammonia-rich liquid under normal temperature to generate ammonium carbonate salt, then the ammonium carbonate salt is subjected to rapid reaction with another part of the leachate for depositing to obtain magnesium(calcium) salt product with high purity, and a reaction-finished solution is further heated to regenerate ammonium salt (NH4HSO4) and ammonia gas for pretreating ores and capturing CO2. According to the invention, the steps of the technology enable complete closed circulation, thereby the chemical agent amount and three wastes are reduced, two high energy consumption steps of CO2 capturing desorption and compression in a traditional method can be avoided, the efficiency for each step is more than 90%, the waste heat in a power plant can be simultaneously used for assisting the regeneration of ammonium salt, and total energy consumption of the technology can be reduced.

Description

technical field [0001] The invention relates to the technical field of flue gas carbon dioxide capture and utilization, in particular to an integrated process of carbon dioxide capture and mineralization. Background technique [0002] The global greenhouse effect caused by the increase in the concentration of greenhouse gases in the atmosphere has caused icebergs to melt, sea levels to rise, species to decrease, and various climate disasters to occur frequently around the world, causing serious economic losses and threatening human survival. carbon dioxide (CO 2 ) As the most important greenhouse gas, its future total control and emission rights allocation have become the focus of international climate negotiations. Governments and energy companies in various countries have paid more and more attention to CO 2 Research on emission control technologies, some countries have taken the lead in starting substantive decarbonization work. With my country's carbon emissions surpa...

AI Technical Summary

Problems solved by technology

[0004] For the traditional carbon dioxide mineralization technology, it is first necessary to use high-temperature heat treatment (600-650°C) and fine grinding (ore particle size less than 38m) for ore activation. -200°C, 150-185bar) to feed the captured gas CO 2 Carry out carbonation reaction, the reaction rate is 78-90% carbonation rate in 1 hour, NaHCO needs to be added in the reaction 3 and NaCl to improve the reaction efficiency, but NaHCO 3 extremely low recycling rate

Another indirect mineralization process using strong acid and strong alkali, first dissolves the ore with strong acid to obtain calcium and magnesium ion leaching solution, and then carries out carbonation reaction with strong alkali. The strong acid and strong alkali required by this process are recycled and regenerated by electrolysis. Very high energy consumption