Method for combined production of lightweight magnesium carbonate and ammonium chloride based on carbon dioxide sequestration

Abstract

The invention relates to a method for the combined production of lightweight magnesium carbonate and ammonium chloride based on carbon dioxide sequestration. According to the technical scheme of the invention, the wastes of potassium salts dried in a salt lake are adopted as raw materials, and the pH value of a solution is adjusted by the liquid ammonia for the absorption of carbon dioxide in the industrial flue gas. An ammonium magnesium carbonate hydrate crystal generated during the above reaction is adopted as an intermediate product and the ammonium magnesium carbonate hydrate is refined to prepare the lightweight magnesium carbonate. In addition, the magnesium chloride raw material is added into an ammonium-rich solution after the reaction, and then the combined production of an ammonium chloride fertilizer is obtained after the solid-liquid separation process and the drying process. During the refining process of the ammonium magnesium carbonate hydrate, the generated carbon dioxide and the generated ammonia gas are fed back to the reaction solution to be re-absorbed, so that the utilization rate of raw materials is improved. The emission of the tail gas is reduced. During the salting-out process, a generated bittern concentrated liquid is fed back to a crystallization reactor to be used as raw materials for the absorption of carbon dioxide. The above method is energy-saving, environment-friendly, high in operability and easy to industrialize.

Description

technical field

[0001] The invention relates to a process for sequestering carbon dioxide with minerals and using it to produce light magnesium carbonate, which belongs to the field of inorganic salt chemical industry and fertilizer production. Background technique

[0002] According to the report of the Intergovernmental Panel on Climate Change (IPCC), since the middle of the 20th century, the extensive use of fossil fuels has led to a continuous increase in the content of atmospheric greenhouse gases, mainly carbon dioxide. This phenomenon is closely related to global climate change. In order to prevent further deterioration of the environment caused by global climate change, it is necessary to stabilize the carbon dioxide content in the atmosphere from both "source" and "sink".

[0003] Since fossil fuels are in a dominant position now and even for a long time in the future, coal, oil, and gas are the main energy sources. In addition, the price of renewable energy will st...

Examples

Embodiment 1

[0042] (1) 1500ml of ammonium chloride solution is prepared, and the concentration of ammonium chloride is 3mol / L. The waste material produced by drying potassium salt in salt lakes is the magnesium chloride solution of 6mol / L for raw material preparation concentration, and the two kinds of solutions are added to the crystallization reactor and mixed Uniformly used as an absorption solution, the volume ratio of ammonium chloride solution to magnesium chloride solution is 5:1, the pH of the solution is adjusted to 9.1 with liquid ammonia, and the flue gas discharged from a cement factory with a carbon dioxide volume fraction of 13% is passed into the absorption solution. The reaction temperature was 53.2°C for 6 hours to obtain slurry I;

[0043] (2) Filter the slurry I obtained in step 1 to obtain mother liquor I and ammonium magnesium carbonate hydrate, the purity of ammonium magnesium carbonate hydrate is 95%, the concentration of magnesium ions in mother liquor I is 0.004mol...

Embodiment 2

[0047] (1) 1500ml of ammonium chloride solution is prepared, and the concentration of ammonium chloride is 3mol / L. The waste material produced by drying potassium salt in salt lakes is the magnesium chloride solution of 6mol / L for raw material preparation concentration, and the two kinds of solutions are added to the crystallization reactor and mixed Uniformly used as the absorption solution, the volume ratio of the ammonium chloride solution and the magnesium chloride solution is 5:1, the pH of the solution is adjusted to 9.8 with liquid ammonia, and the flue gas discharged from the cement factory with a carbon dioxide volume fraction of 15% is passed into the absorption solution. Reaction at 47.6°C for 15 hours to obtain slurry I;

[0048] (2) The slurry I obtained in step 1 is filtered to obtain mother liquor I and ammonium magnesium carbonate hydrate, the purity of ammonium magnesium carbonate hydrate is 96%, the concentration of magnesium ions in mother liquor I is 0.002mo...

Embodiment 3

[0052] (1) 6000ml of ammonium chloride solution is prepared, and the concentration of ammonium chloride is 2mol / L. The waste material produced by drying potassium salts in salt lakes is a magnesium chloride solution of 6mol / L as a raw material, and the two solutions are added to the crystallization reactor and mixed Uniformly used as the absorption solution, the volume ratio of the ammonium chloride solution and the magnesium chloride solution is 3:1, the pH of the solution is adjusted to 9.3 with liquid ammonia, and the flue gas discharged from the cement factory with a carbon dioxide volume fraction of 15% is passed into the absorption solution, and in the reaction Reaction at 25°C for 20 hours to obtain slurry I;

[0053] (2) Filter the slurry I obtained in step 1 to obtain mother liquor I and ammonium magnesium carbonate hydrate, the purity of ammonium magnesium carbonate hydrate is 96.7%, the concentration of magnesium ions in mother liquor I is 0.008mol / L, and the concent...

technical field

[0001] The invention relates to a process for sequestering carbon dioxide with minerals and using it to produce light magnesium carbonate, which belongs to the field of inorganic salt chemical industry and fertilizer production. Background technique

[0002] According to the report of the Intergovernmental Panel on Climate Change (IPCC), since the middle of the 20th century, the extensive use of fossil fuels has led to a continuous increase in the content of atmospheric greenhouse gases, mainly carbon dioxide. This phenomenon is closely related to global climate change. In order to prevent further deterioration of the environment caused by global climate change, it is necessary to stabilize the carbon dioxide content in the atmosphere from both "source" and "sink".

[0003] Since fossil fuels are in a dominant position now and even for a long time in the future, coal, oil, and gas are the main energy sources. In addition, the price of renewable energy will st...

Examples

Embodiment 1

[0042] (1) 1500ml of ammonium chloride solution is prepared, and the concentration of ammonium chloride is 3mol / L. The waste material produced by drying potassium salt in salt lakes is the magnesium chloride solution of 6mol / L for raw material preparation concentration, and the two kinds of solutions are added to the crystallization reactor and mixed Uniformly used as an absorption solution, the volume ratio of ammonium chloride solution to magnesium chloride solution is 5:1, the pH of the solution is adjusted to 9.1 with liquid ammonia, and the flue gas discharged from a cement factory with a carbon dioxide volume fraction of 13% is passed into the absorption solution. The reaction temperature was 53.2°C for 6 hours to obtain slurry I;

[0043] (2) Filter the slurry I obtained in step 1 to obtain mother liquor I and ammonium magnesium carbonate hydrate, the purity of ammonium magnesium carbonate hydrate is 95%, the concentration of magnesium ions in mother liquor I is 0.004mol...

Embodiment 2

[0047] (1) 1500ml of ammonium chloride solution is prepared, and the concentration of ammonium chloride is 3mol / L. The waste material produced by drying potassium salt in salt lakes is the magnesium chloride solution of 6mol / L for raw material preparation concentration, and the two kinds of solutions are added to the crystallization reactor and mixed Uniformly used as the absorption solution, the volume ratio of the ammonium chloride solution and the magnesium chloride solution is 5:1, the pH of the solution is adjusted to 9.8 with liquid ammonia, and the flue gas discharged from the cement factory with a carbon dioxide volume fraction of 15% is passed into the absorption solution. Reaction at 47.6°C for 15 hours to obtain slurry I;

[0048] (2) The slurry I obtained in step 1 is filtered to obtain mother liquor I and ammonium magnesium carbonate hydrate, the purity of ammonium magnesium carbonate hydrate is 96%, the concentration of magnesium ions in mother liquor I is 0.002mo...

Embodiment 3

[0052] (1) 6000ml of ammonium chloride solution is prepared, and the concentration of ammonium chloride is 2mol / L. The waste material produced by drying potassium salts in salt lakes is a magnesium chloride solution of 6mol / L as a raw material, and the two solutions are added to the crystallization reactor and mixed Uniformly used as the absorption solution, the volume ratio of the ammonium chloride solution and the magnesium chloride solution is 3:1, the pH of the solution is adjusted to 9.3 with liquid ammonia, and the flue gas discharged from the cement factory with a carbon dioxide volume fraction of 15% is passed into the absorption solution, and in the reaction Reaction at 25°C for 20 hours to obtain slurry I;

[0053] (2) Filter the slurry I obtained in step 1 to obtain mother liquor I and ammonium magnesium carbonate hydrate, the purity of ammonium magnesium carbonate hydrate is 96.7%, the concentration of magnesium ions in mother liquor I is 0.008mol / L, and the concent...

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