Carbon dioxide absorber and its manufacturing method using sludge, and method for absorbing carbon dioxide in exhaust gas

• US 5,455,013 A
• Filed: 01/28/1994
• Issued: 10/03/1995
• Est. Priority Date: 02/04/1993
• Status: Expired due to Term

• Current Assignee: Kyoei Bussan Kabushiki Kaisha
• Original Assignee: Kyoei Bussan Kabushiki Kaisha
• Inventors: Shibata, Hitoshi, Satokawa, Manabu, Im, Young-Il, Lim, Kang-Haeng
• Primary Examiner(s): McCarthy, Neil
• Application Number:
  US08/188,303
• Time in Patent Office: 613 Days
• Field of Search: 34/79, 34/80, 34/329, 95/139, 423/230, 423/432, 106/793, 106/900, 405/263
• US Class Current: 423/230
• CPC Class Codes: B01D 53/62 Carbon oxides
• CPC Class Codes: B01J 20/041 Oxides or hydroxides
• CPC Class Codes: B01J 20/06 comprising oxides or hydroxides of metals not provided for in group B01J20/04
• CPC Class Codes: B01J 20/08 comprising aluminium oxide or hydroxide; comprising bauxite
• CPC Class Codes: B01J 20/103 comprising silica
• CPC Class Codes: B01J 20/3021 Milling, crushing or grinding
• CPC Class Codes: B01J 2220/42 Materials comprising a mixture of inorganic materials materials coated or impregnated on a carrier B01J20/32
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02C 20/40 of CO2
• CPC Class Codes: Y10S 106/90 Soil stabilization

Abstract

A carbon dioxide absorber is made by separating sludge from exhaust water discharged upon manufacturing fresh mixed concrete or concrete secondary products, then dewatering the separated sludge, and drying and crushing the dewatered sludge into dry fine particles.

Claims

1. A method for absorbing carbon dioxide contained in exhaust gas from a power plant or factory which contains carbon dioxide, comprising the steps of:

separating sludge containing calcium hydroxide from exhaust water discharged upon manufacturing fresh mixed concrete or concrete secondary products;

dewatering the separated sludge;

putting the separated sludge or the dewatered sludge into contact with said exhaust gas.

2. The method of claim 1 including the step of drying the dewatered sludge prior to contact with the exhaust gas.

3. The method of claim 2 including the step of crushing the dried sludge prior to contact with the exhaust gas.

4. A method for reacting carbon dioxide in factory exhaust gas comprising the steps of:

separating sludge from exhaust water discharged during manufacturing of fresh mixed concrete, the sludge containing solids including calcium hydroxide and water; and

putting the sludge into contact with the exhaust gas, whereby the calcium hydroxide is converted to calcium carbonate upon absorption of the carbon dioxide.

5. The method of claim 4 including the step of precipitating the sludge containing exhaust water to separate solids from the water prior to putting the sludge into contact with the exhaust gas.

6. The method of claim 5 wherein precipitating includes separating the sludge into an uppermost layer of supernatant water, an intermediate layer of sludge-containing water, and a lowest layer of sludge.

7. The method of claim 6 further including the step of dewatering the sludge from the lowest layer to remove moisture.

8. A method for absorbing carbon dioxide contained in exhaust gas of a concrete manufacturing factory including the steps of:

separating sludge containing calcium hydroxide from exhaust water discharged upon manufacturing fresh mixed concrete;

removing water from the separated sludge; and

putting the dewatered sludge into contact with the exhaust gas whereby the calcium hydroxide absorbs the carbon dioxide.