METHOD FOR WET REMOVAL OF SULFUR DIOXIDE BY SILICATE BACTERIA-ENHANCED PULP

Abstract

The present disclosure provides a method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp. The method includes: treatment of ore waste residue, activation and domestication of silicate bacteria, preparation of pulp, removal of sulfur dioxide, and resource utilization of a desulfurization product. The present disclosure combines flue gas desulfurization with resource utilization of the ore waste residue, and improves a desulfurization efficiency of the method by the pulp and a utilization rate of ore waste residue resources through silicate bacteria. The present disclosure has a high desulfurization efficiency, simple production process, and low cost, and realizes the recycling of resources such as the ore waste residue, the sulfur dioxide, and silicon. The present disclosure has obvious economic and environmental benefits and broad prospects for use.

Claims

1. A method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp, comprising the following steps: S1, treatment of ore waste residue: crushing, grinding, and sieving the ore waste residue to obtain an ore powder; S2, activation and domestication of silicate bacteria: conducting activation on the silicate bacteria in an activation medium, and conducting domestication on activated silicate bacteria in a domestication medium; S3, preparation of pulp: mixing the ore powder obtained in step S1, activated and domesticated silicate bacteria obtained in step S2, nutrients and distilled water to obtain the pulp, conducting culture until the pulp precipitates dissolved silicon, and subjecting the pulp to solid-liquid separation to remove silicon in ore; S4, removal of sulfur dioxide: subjecting treated pulp obtained in step S3 and flue gas containing sulfur dioxide to a contact reaction, to remove the sulfur dioxide in the flue gas; and S5, resource utilization of a desulfurization product: subjecting a reaction product obtained in step S4 to solid-liquid separation, impurity removal, concentration, and crystallization, and drying sequentially.

2. The method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp according to claim 1, wherein in step S1, the ore waste residue is one or more selected from the group consisting of manganese oxide ore, manganese carbonate ore, pyrite, red mud, phosphorite, magnesium ore, lead-zinc ore, copper ore, nickel ore, vanadium titano-magnetite, copper slag, electrolytic manganese slag, magnesium slag, and halobolite.

3. The method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp according to claim 1, wherein in step S1, the ore powder has a particle size of less than or equal to 0.18 mm.

4. The method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp according to claim 1, wherein in step S2, the silicate bacteria are Bacillus mucilaginosus and/or Bacillus circulans.

5. The method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp according to claim 1, wherein in step S2, the activation medium comprises the following raw materials: 1,000 mL of distilled water, 3 g to 6 g of sucrose, 2 g to 5 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, 0.5 g to 1 g of MgSO.sub.4.Math.7H.sub.2O, and 1.0 g of a bauxite powder; the activation is conducted at 15° C. to 45° C., 150 r/min to 400 r/min and a pH value of 5 to 9.

6. The method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp according to claim 1, wherein in step S2, the domestication medium comprises the following raw materials: 1,000 mL of distilled water, 3 g to 6 g of sucrose, 2 g to 5 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, and 0.5 g to 1 g of MgSO.sub.4.Math.7H.sub.2O; the domestication is conducted at 15° C. to 45° C., 150 r/min to 400 r/min and a pH value of 5 to 9.

7. The method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp according to claim 1, wherein in step S3, the preparation of pulp specifically comprises: 10 g to 100 g of the ore powder, 3 g to 6 g of sucrose, 2 g to 5 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, 0.5 g to 1 g of MgSO.sub.4.Math.7H.sub.2O, and the activated and domesticated silicate bacteria with a viable count of 10.sup.8 to 10.sup.11 are added to each 1 L of the distilled water; and the pulp is cultured at 15° C. to 45° C., 150 r/min to 400 r/min and a pH value of 5 to 9 for 5 d to 15 d.

8. The method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp according to claim 1, wherein in step S4, the flue gas containing sulfur dioxide is environment set smoke-derived flue gas and/or metal smelting-derived tail gas with a sulfur dioxide concentration of less than or equal to 5,000 mg/m.sup.3.

9. The method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp according to claim 1, wherein in step S4, the contact reaction is conducted in a one-stage absorption reaction device or multi-stage absorption reaction devices; the multi-stage absorption reaction devices are connected in series sequentially, and each stage of the multi-stage absorption reaction devices is equipped with an independent pulp circulation pump and an independent pulp circulation pool; the flue gas containing sulfur dioxide is introduced from a first-stage absorption reaction device and discharged from a last-stage absorption reaction device, and the pulp in the absorption reaction device is subjected to the contact reaction with the flue gas.

10. The method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp according to claim 1, wherein in step S4, the contact reaction is conducted at 20° C. to 60° C. for 4 sec to 30 sec.

Description

DETAILED DESCRIPTION

[0015] The present disclosure is further described below by combining embodiments and is not limited in any way. Any transformation or replacement based on the teachings of the present disclosure falls within the protection scope of the present disclosure.

[0016] The present disclosure includes the following steps: [0017] S1, treatment of ore waste residue: crushing, grinding and sieving the ore waste residue to obtain an ore powder; [0018] S2, activation and domestication of silicate bacteria: conducting activation on the silicate bacteria in an activation medium, and conducting domestication on activated silicate bacteria in a domestication medium; [0019] S3, preparation of pulp: mixing the ore powder obtained in step S1, activated and domesticated silicate bacteria obtained in step S2, nutrients and distilled water to obtain the pulp, conducting culture until the pulp precipitates dissolved silicon, and subjecting the pulp to solid-liquid separation to remove silicon in ore; [0020] S4, removal of sulfur dioxide: subjecting treated pulp obtained in step S3 and flue gas containing sulfur dioxide to a contact reaction, to remove the sulfur dioxide in the flue gas; and [0021] S5, resource utilization of a desulfurization product: subjecting a reaction product obtained in step S4 to solid-liquid separation, impurity removal, concentration and crystallization, and drying sequentially, to recycle valuable metals.

[0022] In the present disclosure, in step S1, the ore waste residue is one or more selected from the group consisting of manganese oxide ore, manganese carbonate ore, pyrite, red mud, phosphorite, magnesium ore, lead-zinc ore, copper ore, nickel ore, vanadium titano-magnetite, copper slag, electrolytic manganese slag, magnesium slag, and halobolite.

[0023] In the present disclosure, in step S1, the ore powder has a particle size of less than or equal to 0.18 mm.

[0024] In the present disclosure, in step S2, the silicate bacteria are Bacillus mucilaginosus and/or Bacillus circulans.

[0025] In the present disclosure, in step S2, the activation medium includes the following raw materials: 1,000 mL of distilled water, 3 g to 6 g of sucrose, 2 g to 5 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, 0.5 g to 1 g of MgSO.sub.4.Math.7H.sub.2O, and 1.0 g of a bauxite powder; the activation is conducted at 15° C. to 45° C., 150 r/min to 400 r/min and a pH value of 5 to 9; the bauxite is added to the medium as a silicate mineral, and is decomposed and utilized by the silicate bacteria, promoting the growth of silicate bacteria.

[0026] In the present disclosure, in step S2, the domestication medium includes the following raw materials: 1,000 mL of distilled water, 3 g to 6 g of sucrose, 2 g to 5 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, and 0.5 g to 1 g of MgSO.sub.4.Math.7H.sub.2O; the domestication is conducted at 15° C. to 45° C., 150 r/min to 400 r/min and a pH value of 5 to 9.

[0027] In the present disclosure, in step S3, the preparation of pulp specifically includes: 10 g to 100 g of the ore powder, 3 g to 6 g of sucrose, 2 g to 5 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, 0.5 g to 1 g of MgSO.sub.4.Math.7H.sub.2O, and the activated and domesticated silicate bacteria with a viable count of 10.sup.8 to 10.sup.11 are added to each 1 L of the distilled water; and the pulp is cultured at 15° C. to 45° C., 150 r/min to 400 r/min and a pH value of 5 to 9 for 5 d to 15 d.

[0028] In the present disclosure, in step S4, the flue gas containing sulfur dioxide is environment set smoke-derived flue gas and/or metal smelting-derived tail gas with a sulfur dioxide concentration of less than or equal to 5,000 mg/m.sup.3.

[0029] In the present disclosure, in step S4, the contact reaction is conducted in a one-stage absorption reaction device or multi-stage absorption reaction devices; the multi-stage absorption reaction devices are connected in series sequentially, and each stage of the multi-stage absorption reaction devices is equipped with an independent pulp circulation pump and an independent pulp circulation pool; the flue gas containing sulfur dioxide is introduced from a first-stage absorption reaction device and discharged from a last-stage absorption reaction device, and the pulp in the absorption reaction device is subjected to the contact reaction with the flue gas. The absorption reaction device is a flue gas purification device well known to those skilled in the art; during the desulfurization, the multi-stage absorption reaction devices realize multi-stage circulating purification of a desulfurized slurry, improving a desulfurization efficiency and saving a cost.

[0030] In the present disclosure, in step S4, the contact reaction is conducted at 20° C. to 60° C. for 4 sec to 30 sec.

[0031] The present disclosure is further described below in conjunction with Examples 1 to 3.

Example 1

[0032] A method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp included the following steps: [0033] S1, treatment of ore waste residue: manganese oxide ore, manganese carbonate ore, pyrite, red mud, phosphorite, magnesium ore, lead-zinc ore, copper ore, nickel ore, vanadium titano-magnetite, copper slag, electrolytic manganese slag, magnesium slag, and halobolite were crushed, ground, and sieved by an 80-mesh sieve according to a mass ratio of 1:1:1:1:1:1:1:1:1:1:1:1:1:1 separately, and mixed well to obtain an ore powder. [0034] S2, activation and domestication of silicate bacteria: activation was conducted on Bacillus mucilaginosus in an activation medium, and domestication was conducted on activated Bacillus mucilaginosus in a domestication medium; where the activation medium included the following raw materials: 1,000 mL of distilled water, 4.5 g of sucrose, 3.5 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, 0.75 g of MgSO.sub.4.Math.7H.sub.2O, and 1.0 g of a bauxite powder; the activation was conducted at 30° C., 275 r/min and a pH value of 7; and the domestication medium included the following raw materials: 1,000 mL of distilled water, 4.5 g of sucrose, 3.5 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, and 0.75 g of MgSO.sub.4.Math.7H.sub.2O; the domestication was conducted at 30° C., 275 r/min and a pH value of 7. [0035] S3, preparation of pulp: the ore powder obtained in step S1, activated and domesticated Bacillus mucilaginosus obtained in step S2, nutrients and distilled water were mixed to obtain the pulp, where the preparation of pulp specifically included: 55 g of the ore powder, 4.5 g of sucrose, 3.5 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, 0.75 g of MgSO.sub.4.Math.7H.sub.2O, and the activated and domesticated Bacillus mucilaginosus were added to each 1 L of the distilled water; and the pulp was cultured at 30° C., 275 r/min and a pH value of 7 for 10 d, and the pulp was subjected to solid-liquid separation to remove silicon in ore. [0036] S4, removal of sulfur dioxide: treated pulp obtained in step S3 and environment set smoke-derived flue gas were subjected to a contact reaction at 40° C. for 17 sec, to remove the sulfur dioxide in the flue gas. [0037] S5, resource utilization of a desulfurization product: a reaction product obtained in step S4 was subjected to solid-liquid separation, impurity removal, concentration and crystallization, and drying sequentially.

[0038] The gas after flue gas desulfurization in this example had a sulfur dioxide concentration of 99 mg/m.sup.3, and a desulfurization efficiency of 96.7%, which complied with GB-26132-2010.

Example 2

[0039] A method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp included the following steps: [0040] S1, treatment of ore waste residue: manganese oxide ore, pyrite, red mud, phosphorite, magnesium ore, and copper ore were crushed, ground, and sieved by an 80-mesh sieve according to a mass ratio of 1:1:1:1:1:1 separately, and mixed well to obtain an ore powder. [0041] S2, activation and domestication of silicate bacteria: activation was conducted on Bacillus circulans in an activation medium, and domestication was conducted on activated Bacillus circulans in a domestication medium; where the activation medium included the following raw materials: 1,000 mL of distilled water, 3 g of sucrose, 2 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, 0.5 g of MgSO.sub.4.Math.7H.sub.2O, and 1.0 g of a bauxite powder; the activation was conducted at 15° C., 150 r/min and a pH value of 5; and the domestication medium included the following raw materials: 1,000 mL of distilled water, 3 g of sucrose, 2 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, and 0.5 g of MgSO.sub.4.Math.7H.sub.2O; the domestication was conducted at 15° C., 150 r/min and a pH value of 5. [0042] S3, preparation of pulp: the ore powder obtained in step S1, activated and domesticated Bacillus circulans obtained in step S2, nutrients and distilled water were mixed to obtain the pulp, where the preparation of pulp specifically included: 10 g of the ore powder, 3 g of sucrose, 2 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, 0.5 g of MgSO.sub.4.Math.7H.sub.2O, and the activated and domesticated Bacillus circulans were added to each 1 L of the distilled water; and the pulp was cultured at 15° C., 150 r/min and a pH value of 5 for 5 d, and the pulp was subjected to solid-liquid separation to remove silicon in ore. [0043] S4, removal of sulfur dioxide: treated pulp obtained in step S3 and metal smelting-derived tail gas were subjected to a contact reaction at 20° C. for 4 sec in a one-stage absorption reaction device, to remove the sulfur dioxide in the flue gas. [0044] S5, resource utilization of a desulfurization product: subjecting a reaction product obtained in step S4 to solid-liquid separation, impurity removal, concentration and crystallization, and drying sequentially.

Example 3

[0045] A method for wet removal of sulfur dioxide by silicate bacteria-enhanced pulp included the following steps: [0046] S1, treatment of ore waste residue: phosphorite was crushed, ground, and sieved by an 80-mesh sieve, and mixed well to obtain an ore powder. [0047] S2, activation and domestication of silicate bacteria: Bacillus mucilaginosus and Bacillus circulans were used as silicate bacteria; activation was conducted on the silicate bacteria in an activation medium, and domestication was conducted on activated silicate bacteria in a domestication medium; where the activation medium included the following raw materials: 1,000 mL of distilled water, 6 g of sucrose, 5 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, 1 g of MgSO.sub.4.Math.7H.sub.2O, and 1.0 g of a bauxite powder; the activation was conducted at 45° C., 400 r/min and a pH value of 9; and the domestication medium included the following raw materials: 1,000 mL of distilled water, 6 g of sucrose, 5 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, and 1 g of MgSO.sub.4.Math.7H.sub.2O; the domestication was conducted at 45° C., 400 r/min and a pH value of 9. [0048] S3, preparation of pulp: the ore powder obtained in step S1, activated and domesticated silicate bacteria obtained in step S2, nutrients and distilled water were mixed to obtain the pulp, where the preparation of pulp specifically included: 100 g of the ore powder, 6 g of sucrose, 5 g of Na.sub.2HPO.sub.4, 0.1 g of CaCO.sub.3, 0.005 g of FeCl.sub.3, 1 g of MgSO.sub.4.Math.7H.sub.2O, and the activated and domesticated silicate bacteria were added to each 1 L of the distilled water; and the pulp was cultured at 45° C., 400 r/min and a pH value of 9 for 15 d, and the pulp was subjected to solid-liquid separation to remove silicon in ore. [0049] S4, removal of sulfur dioxide: treated pulp obtained in step S3 and mixed flue gas of environment set smoke-derived flue gas and metal smelting-derived tail gas were subjected to a contact reaction at 60° C. for 30 sec in multi-stage absorption reaction devices, to remove the sulfur dioxide in the flue gas. [0050] S5, resource utilization of a desulfurization product: subjecting a reaction product obtained in step S4 to solid-liquid separation, impurity removal, concentration, and crystallization, and drying sequentially.