KR100871393B1 - Method for manufacture of non-polluting portland cement - Google Patents

Abstract

A method of manufacturing non- polluting portland cement is provided to relieve strong alkalinity of the cement and to remove toxic materials by preventing being emitted by adding a combination of an activity alumina, a calcium chloride and sugar in the cement and dissolving a chrome by de-wetting and catalytic action. A method of manufacturing non- polluting portland cement includes steps of: evaporating moisture and stabilizing a calcium chloride and a sugar carbide which becomes an anhydride by adding a heat of 250-300‹C after mixing the calcium chloride and sugar at a rate of 50% and dissolving it in water; adding and mixing the activity alumina in range of 1-3% of a cement amount; and wrapping and developing the cement in which an additive is mixed up.

Description

Method for manufacture of non-polluting portland cement

1 is a process chart for explaining a method for manufacturing a pollution-free portland cement according to the present invention.

The present invention relates to a method for manufacturing Portland cement, and more particularly, to a composition using activated alumina (Al ₂ O ₂ ), calcium chloride (CaCl ₂ ) and sugar to cement to solve the pollution problem of cement. One method is to prepare a pollution-free portland cement.

Cement, which is widely used today, is generally referred to as Portland Cement. In the broader sense, cement means Inorganic Cementing Material that hardens when kneaded with water.

Portland cement is a powder made by mixing a sufficient amount of raw materials containing lime, silica, alumina and iron oxide as the main components in a suitable ratio, and adding a portion of gypsum to a sintered clinker.

It is widely used in various construction and civil engineering materials, such as buildings, roads, bridges, blocks, sleepers, and poles, using concrete molded by mixing aggregates such as gravel and sand with water in such Portland cement.

However, when kneading a mixture of sand or gravel crushed stone with the clinker constituents of Portland cement, it loses fluidity and condenses after a while, and then various toxic substances are generated by chemical reaction during the curing process. These toxic substances not only deteriorate the health of residents living in concrete buildings, but also cause damage to animals and plants, causing serious environmental pollution.

In addition, when the cement is low in temperature and high in humidity, the water-soluble component contained in the cement hardened body moves to the surface and only white water is evaporated, causing whitening to precipitate whitening. Not only could the appearance not be kept beautiful, but there were also closed ends such as lowering the strength of the concrete.

Thus, in recent years, a number of prior art related to the production of non-toxic cement that effectively neutralizes the toxicity of cement has been proposed. As an example, there is a "method for producing a non-toxic cement" of Korean Patent Publication No. 2005-104936 (Nov. 3, 2005) and "concrete admixture and non-toxic concrete using the same" of the registered Patent No. 709669 (2007. 4.13).

In Korean Patent Application Publication No. 2005-104936 (Nov. 3, 2005), the method for producing non-toxic cement has a variety of minerals obtained by collecting minerals such as sericite, chlorite, and illite. The particles are crushed into particles to remove impurities, followed by natural drying to dry the moisture contained in the epidermal layer of the mineral.The dried minerals are put into a drying furnace, followed by heating at 500-700 ℃ to completely dry the moisture contained in the mineral. Then, the dried minerals are finely ground and pulverized into fine powders so as to maintain a particle size of 200 mesh or more, 88-91% by weight of cement powder, 5-7% by weight of sericite, 0.4-0.6% by weight of chromite, and 2 ~ 3% by weight of light powder and 0.8 ~ 1.2% by weight of fly ash powder are mixed evenly, and the mixed powders are put in a bag and packaged, so that the strong adsorption power of minerals and large amount of negative ions are released And there is a disclosed technology that enables to effectively neutralize the toxicity (毒性) of cement or the like by.

 "Concrete admixtures and non-toxic concretes using the same" in Korean Patent No. 709669 (April 13, 2007) include 60 to 75 parts by weight of filler, 16 to 23 parts by weight of cement, and 0.2 to 1.0 parts by weight of admixture based on the weight of cement. Including a 6 to 12 parts by weight of a dilute admixture, there is disclosed a technique for minimizing the emission of pollutants while having the strength characteristics, durability, fire resistance, and workability required for concrete.

By the way, Portland cement products absorb moisture in the air and calcium hydroxide produced by hydration combines with carbon dioxide in the air to form lime carbonate. It is caused to be coated with, and about 6.0% of magnesium oxide (MgO) contained in the cement dissolves chromium contained in the ore, releasing hexavalent chromium toxicity to the outside.

Hexavalent chromium compounds, such as chromic acid (chromium trioxide) and chromates, easily penetrate the mucous membranes of skin and have a strong influence on life. For example, skin contact causes local symptoms such as burns, erosions, and necrosis, while inhalation causes symptoms of coughing, green-yellowing, shortness of breath, and pulmonary congestion. If the hexavalent chromium compound is swallowed, it causes side effects such as vomiting and abdominal pain of green yellow mucus. Then, as a systemic symptom, nausea and vomiting continue to cause liver and gastrointestinal harm. In particular, in severe cases of hematuria, deficiency, and urinary poisoning, it leads to death. Lesions of the kidney are the main changes in necrosis, the appearance of urine tubules.

The primary stimulation of hexavalent chromium causes needle-like rashes and papules on the skin of the nail, the back of the hands (particularly between the joints of the fingers, between the fingers, the joints of the hands, etc.), the face, and the toes. This rash is prone to eczema, itching and scratches, abrasions, etc., the area develops into ulcers and becomes chrome ulcers. Like mucous membranes, mucous membranes are also prone to disease, and inflammation and ulcers on the nasal mucosa and larynx are easy.

The primary stimulation of chromium compounds, such as chronic respiratory inflammation, allergic asthma, and other actions on the respiratory system should be careful.

In animal carcinogenesis studies, tumors of both trivalent and hexavalent forms are recognized, and there are reports of epidemiological investigations in humans. Hexavalent chromium is more than 9 times more absorbent than trivalent chromium, which is a serious pollution problem where source prevention measures are absolutely desired.

As described above, there is an urgent need for measures to neutralize the toxicity of cement and to suppress the release of hexavalent chromium, a harmful substance with a strong effect on living organisms.

Therefore, the object of the present invention was devised in view of the above-mentioned point, by mixing calcium chloride (CaCl ₂ ), sugar carbide, activated alumina (Al ₂ O ₂ ) as an additive in cement to absorb toxic substances and moisture The present invention provides a method for producing a pollution-free portland cement that can remove cement odors and toxic substances, prevent whitening, and inhibit the formation of hexavalent chromium.

The method for producing the pollution-free portland cement of the present invention for achieving the above object is, in the method for producing the pollution-free portland cement, (1) after mixing calcium chloride and sugar in a certain ratio to dissolve in water, and then evaporate water Adding 250-300 ° C. heat to form anhydrous calcium chloride and sugar carbide, (2) adding the anhydrous calcium chloride and sugar carbide to within 2% of the amount of cement and mixing; 3) adding and mixing activated alumina within a range of 1-3% of the amount of cement, and (4) packaging and commercializing the cement mixed with the additives.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a process chart for explaining a method for manufacturing a pollution-free portland cement according to the present invention.

In Fig. 1, 50% of calcium chloride and 50% of sugar are dissolved by boiling in water, followed by evaporation of water and heating at 250-300 ° C. to form earthy carbide. Calcium chloride and sugar carbide, which are anhydrides whose water molecules are released from the compound by evaporation of water, are added and mixed within 2% of the amount of cement.

Calcium chloride (CaCl ₂ ) is strongly deliquescent and absorbs moisture and is widely used as a desiccant. Therefore, mixing and packing anhydrous calcium chloride and sugar carbide in cement does not cause hardening reaction, alleviates strong alkaline components during mortar or concrete work, absorbs odors and toxic substances and releases moisture without releasing it to the outside. Absorbs well and eliminates whitening caused by evaporation of water.

In addition, activated alumina is added and mixed within 1-3% of the amount of cement as the most important preventive measure of hexavalent chromium. Packaged and commercialized cement containing anhydrous calcium chloride, sugar carbide and activated alumina as additives. Cement, carbide, and activated alumina are each mixed in a ratio of 98: 1: 1 by weight.

Here, activated alumina (Al ₂ O ₂ ) blocks the root cause of dissolving about 6.0% of magnesium oxide contained in cement raw materials by dissolving chromium contained in sand or gravel stone by dehumidification and catalysis of gas. Let's do it.

As a result of measuring the contamination of heavy metals through construction and civil engineering materials, ie, concrete using Portland cement manufactured by the present embodiment, heavy metals are not detected at all and can be used to replace products made of natural construction or civil engineering materials. In particular, no hexavalent chromium compound was detected.

Believing that the pollution of Portland cement is taking the opportunity of coexistence in living things, the solution to dismantle the cement revetment block installed in the current river and install new natural stone and crushed stone to make natural river will cause another environmental problem. At the required time, the cement mixture according to this embodiment can present a preferred solution.

As described above, the method for producing the pollution-free Portland cement of the present invention is a strong alkaline property of the cement by adding a combination of activated alumina, calcium chloride and sugar to the cement to prevent it from being released by dissolving chromium by dehumidification and catalysis. It is effective in reducing pollution, removing odors and toxic substances, and preventing whitening and the formation of hexavalent chromium to provide pollution-free cement.

Claims (3)

In the method for producing a pollution-free portland cement, (1) mixing calcium chloride and sugar at a rate of 50%, respectively, dissolving and dissolving in water, evaporating water, and applying 250-300 ° C. to form calcium chloride and sugar carbide of anhydride; (2) adding and mixing calcium chloride and sugar carbide of the anhydride within 2% of the amount of cement; (3) adding and mixing activated alumina within 1-3% of the amount of cement; And (4) A method for producing a pollution-free portland cement comprising the step of packaging and cementing the cement mixed with the additive. delete The method of claim 1, wherein the cement, the carbide, and the activated alumina are each mixed in a ratio of 98: 1: 1 based on the total weight.

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