KR100587915B1 - Method for producing calcium sulfate alpa-hemihydrate from FGD gypsum by microwave - Google Patents

Method for producing calcium sulfate alpa-hemihydrate from FGD gypsum by microwave Download PDF

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KR100587915B1
KR100587915B1 KR1020040086347A KR20040086347A KR100587915B1 KR 100587915 B1 KR100587915 B1 KR 100587915B1 KR 1020040086347 A KR1020040086347 A KR 1020040086347A KR 20040086347 A KR20040086347 A KR 20040086347A KR 100587915 B1 KR100587915 B1 KR 100587915B1
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gypsum
alpha
microwave
type hemihydrate
hemihydrate gypsum
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KR20060037166A (en
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김기형
박승수
안희수
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한국전력공사
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F11/00—Compounds of calcium, strontium, or barium
    • C01F11/46—Sulfates
    • C01F11/464—Sulfates of Ca from gases containing sulfur oxides
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B11/00—Calcium sulfate cements
    • C04B11/02—Methods and apparatus for dehydrating gypsum
    • C04B11/028—Devices therefor characterised by the type of calcining devices used therefor or by the type of hemihydrate obtained
    • C04B11/032—Devices therefor characterised by the type of calcining devices used therefor or by the type of hemihydrate obtained for the wet process, e.g. dehydrating in solution or under saturated vapour conditions, i.e. to obtain alpha-hemihydrate
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B11/00—Calcium sulfate cements
    • C04B11/26—Calcium sulfate cements strating from chemical gypsum; starting from phosphogypsum or from waste, e.g. purification products of smoke
    • C04B11/262—Calcium sulfate cements strating from chemical gypsum; starting from phosphogypsum or from waste, e.g. purification products of smoke waste gypsum other than phosphogypsum
    • C04B11/264—Gypsum from the desulfurisation of flue gases

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  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Inorganic Chemistry (AREA)
  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)

Abstract

본 발명은 마이크로파를 이용한 배연탈황석고로부터 알파형 반수석고를 제조하는 방법을 제공하기 위한 것으로 기존의 가압수증기법을 이용하는 가압반응기(Autoclave)에 마이크로파를 조사할 수 있도록 하여 알파형 반수석고의 생성시간을 단축시킬 수 있을 뿐만 아니라 반응 종료 후 생성된 알파형 반수석고를 가압반응기에 부착되어 있는 마이크로파만으로 건조시킴으로써 에너지 효율을 높여 알파형 반수석고의 제조비용을 낮출 수 있도록 한 것이 특징이다.The present invention is to provide a method for producing alpha-type hemihydrate gypsum from a flue gas desulfurization gypsum using a microwave, it is possible to irradiate microwaves to a pressure reactor (Autoclave) using a conventional pressurized steam method to produce alpha-type hemihydrate gypsum In addition to shortening, the alpha-type hemihydrate gypsum produced after the reaction is dried only with microwaves attached to the pressure reactor to increase energy efficiency, thereby reducing the manufacturing cost of the alpha-type hemihydrate gypsum.

마이크로파, 배연탈황석고, 알파형, 반수석고, 가압반응기Microwave, flue gas desulfurization gypsum, alpha type, hemihydrate gypsum, pressure reactor

Description

마이크로파를 이용한 배연탈황석고로부터 알파형 반수석고의 제조방법{Method for producing calcium sulfate alpa-hemihydrate from FGD gypsum by microwave}Method for producing alpha-type hemihydrate gypsum from flue gas desulfurization gypsum using microwave {Method for producing calcium sulfate alpa-hemihydrate from FGD gypsum by microwave}

도 1은 본 발명에 따른 스팀과 마이크로파를 이용하여 알파형의 반수석고를 제조하는 공정도이다. 1 is a process chart for preparing alpha-type hemihydrate gypsum using steam and microwave according to the present invention.

도 2는 본 발명의 방법에 의해 제조한 알파형 반수석고의 SEM 사진이다.2 is an SEM photograph of alpha-type hemihydrate gypsum prepared by the method of the present invention.

도 3은 본 발명의 방법에 따라 제조한 알파형 반수석고의 DSC 그래프이다.3 is a DSC graph of alpha-type hemihydrate gypsum prepared according to the method of the present invention.

<도면의 주요부분에 대한 부호의 설명><Description of the symbols for the main parts of the drawings>

1 --- 탈황석고 저장조, 2 --- 탈황석고 이송장치1 --- desulfurized gypsum reservoir, 2 --- desulfurized gypsum feeder

3 --- 혼합기 4 --- 첨가제 이송장치3 --- Mixer 4 --- Additive Feeder

5 ---- 첨가제 저장조 6 ---- 압력 성형기5 ---- additive reservoir 6 ---- pressure molding machine

7 ---- 성형체 운반대 8 ---- 마이크로파 가압 반응기7 ---- molded carrier 8 ---- microwave pressurized reactor

9 ---- 분쇄기 10 ---- 알파형 반수석고 저장조9 ---- Grinding Machine 10 ---- Alpha Type Half Gypsum Storage Tank

본 발명은 화력발전소 및 일반 산업공정에서 부산되는 배연탈황석고를 수열 합성시켜 알파형 반수석고를 제조하는 방법에 관한 것이다. 더욱 상세하게는 수분을 함유하고 있는 배연탈황석고의 성형체에 스팀과 더불어 마이크로파(Microwave)를 조사하여 고강도로 제조할 수 있고, 제조비용도 대폭적으로 절감시킬 수 있는 마이크로파를 이용한 배연탈황석고로부터 알파형 반수석고를 제조하는 방법에 관한 것이다. The present invention relates to a method for producing alpha-type hemihydrate gypsum by hydrothermal synthesis of flue gas desulfurized gypsum from Busan thermal power plants and general industrial processes. More specifically, it can be produced in high strength by irradiating microwave and microwave to the molded body of flue gas desulfurized gypsum containing water, and it can be produced in high strength, and alpha type from flue gas desulfurized gypsum using microwave which can greatly reduce the manufacturing cost. The present invention relates to a method for producing hemihydrate gypsum.

일반적으로 석고는 크게 천연석고와 화학석고로 나눌 수 있으나 SO3의 함량에 따라 순도가 결정되며 석고에 들어 있는 결정수의 함량에 따라 이수석고, 반수석고, 무수석고로 구분된다. 이수석고는 탈수조건에 따라 알파(α)형, 베타(β)형, 또는 무수석고로 전이하게 되는데 건조한 상태에서 탈수가 이루어지는 경우에는 베타형으로 습식상태에서 탈수되는 경우에는 알파형으로 전이한다. 탈수온도는 일반적으로 110℃ 이상 140℃ 이내이다. 생성된 알파형 반수석고는 베타형 반수석고보다 강도가 10배 이상 뛰어나고 초기 경화시간이 짧아 건축용, 치과용, 금형용 등 다양한 용도로 이용되고 있으나 비싼 가격 때문에 사용이 제한적이다.In general, gypsum can be divided into natural gypsum and chemical gypsum, but the purity is determined according to the content of SO 3 and is divided into dihydrate gypsum, hemihydrate gypsum and anhydrous gypsum according to the amount of crystal water in gypsum. Isuly gypsum is transferred to alpha (α), beta (β), or anhydrous gypsum, depending on the dehydration conditions. If dehydration occurs in a dry state, it is converted to beta form. Dehydration temperature is generally 110 degreeC or more and 140 degrees C or less. The produced alpha-type hemihydrate gypsum is more than 10 times stronger than beta-type hemihydrate gypsum and its initial curing time is short, so it is used for various purposes such as construction, dental and mold, but its use is limited due to its high price.

현재까지 이수석고로부터 알파형 반수석고를 제조하는 방법으로는 상압 수용액법, 가압 수용액법, 가압수증기법, 마이크로파법 등이 소개되어 있으나, 가장 널리 상용화되고 있는 방법은 가압반응기(Autoclave)를 이용한 가압수증기법이다. To date, alpha-type hemihydrate gypsum is prepared from atmospheric pressure aqueous solution method, pressurized aqueous solution method, pressurized steam method, microwave method, etc., but the most widely used method is pressurization using autoclave. It is a vapor technique.

지금까지 알려진 가압수증기법에 의한 알파형 반수석고의 제조방법은 주로 가압반응기에 이수석고를 투입한 다음 스팀으로 가압반응기의 압력을 2kgf/㎠ ~ 5kgf/㎠, 온도 120℃ ~ 150℃의 조건하에서 5 ~ 8시간 유지하여 제조하는 것으로 알려져 있다. 반응온도를 높이면 반응시간은 단축되나 결정형상은 주로 침상으로 석출되어 혼수율이 높아짐에 따라 강도가 저하된다. 반대로 반응온도를 낮추게 되면 결정형상은 주상으로 바뀔 수 있으나 알파형 반수석고로 전이되는데 걸리는 반응시간이 길어지고 에너지 비용을 많이 소모하는 단점이 있다. The method for producing alpha-type hemihydrate gypsum by the pressurized steam method so far is mainly put the hydrated gypsum into the pressurized reactor and then pressurize the pressure of the pressurized reactor to 2kg f / ㎠ ~ 5kg f / ㎠, the temperature of 120 ℃ ~ 150 ℃ It is known to manufacture by keeping for 5 to 8 hours under. When the reaction temperature is increased, the reaction time is shortened, but the crystal form is mainly precipitated as a needle, and the strength decreases as the coma ratio increases. On the contrary, when the reaction temperature is lowered, the crystal form may be changed into the main phase, but the reaction time required to transfer to the alpha-type hemihydrate gypsum is long and consumes a lot of energy costs.

수용액 내에서 칼슘의 과포화도를 조절하여 알파형 반수석고를 석출시키는 방법으로는 가압 수용액법이나 상압 수용액법등이 알려져 있다. 상압 수용액법은 과포화도를 감소시키고 전이온도를 낮추기 위하여 고농도의 염화칼슘이나 황산용액을 사용하고 있으나 생성된 알파형 반수석고의 입자가 침상으로서 혼수율이 떨어지고 강도가 저하되는 단점과 수세가 필요하다는 단점 때문에 상용화되지는 않은 것으로 알려져 있다. As a method of precipitating alpha-type hemihydrate gypsum by adjusting the degree of supersaturation of calcium in aqueous solution, a pressurized aqueous solution method or an atmospheric pressure aqueous solution method is known. Atmospheric pressure solution method uses high concentration of calcium chloride or sulfuric acid solution to reduce super saturation and lower transition temperature. It is not known to be commercially available.

가압 수용액법은 20 ~ 50%의 이수석고 슬러리에 매정제를 첨가하고 가압반응기에서 120 ~ 140℃, 한 시간 정도 반응시켜 알파형 반수석고를 제조하는 방법으로 비교적 잘 발달된 결정을 얻을 수 있으나 슬러리를 취급하기 때문에 탈수과정이 필요하고 장치가 복잡하다는 단점이 있다. In the pressurized aqueous solution method, a well-developed crystal can be obtained by adding a refiner to a slurry of 20-50% of dihydrate gypsum and preparing alpha-type hemihydrate gypsum by reacting at 120-140 ° C for one hour in a pressure reactor. Dehydration process is necessary because of the handling and has the disadvantage that the device is complicated.

마이크로파를 이용하여 탈황석고로부터 알파형 반수석고를 제조하는 방법은 비교적 최근에 국내외에서 몇몇의 연구가 진행되고 있는 것으로 알려져 있다.It is known that a method of preparing alpha-type hemihydrate gypsum from desulfurized gypsum using microwave has been studied in recent years at home and abroad.

국내에서 소개된 마이크로파를 이용한 알파형 반수석고를 제조 방법(대한민국특허 제1999-0054430호)은 수분 약 10% 정도 함유하는 배연탈황석고를 벨트 컨베이어를 통하여 이송되는 도중에 마이크로파를 조사하여 알파형 반수석고를 생성하는 것으로 기재하고 있으나, 본 발명자들의 실험결과 상기의 방식으로는 알파형 반수석고를 제조하지 못하였다. 이러한 이유는 상압 하에서 수분이 포함된 석고에 마 이크로파를 조사하면 최초에는 수분이 증발하면서 건조되어 이수석고로 되고 건조된 이수석고에 마이크로파를 계속 조사하면 석고는 베타형 반수석고를 거쳐 무수석고로 전이되기 때문인 것으로 판단된다. The method of manufacturing alpha-type hemihydrate gypsum using microwave introduced in Korea (Korean Patent No. 1999-0054430) is an alpha-type hemihydrate gypsum by irradiating microwaves during the transfer of flue gas desulfurization gypsum containing about 10% moisture through a belt conveyor. Although it is described as to produce, but the results of the inventors of the present invention did not produce the alpha-type hemihydrate gypsum in the above manner. This is because when microwave is irradiated with water containing gypsum under atmospheric pressure, the water is first evaporated to dry as moisture evaporates, and when irradiated with microwave on dried dihydrate gypsum, the gypsum transfers to beta-type gypsum and to anhydrous gypsum. It seems to be because

상압의 건식상태에서 마이크로파 단독으로 이수석고를 탈수시키면 알파형 반수석고보다는 베타형 반수석고가 형성된다. 따라서 마이크로파를 조사할 경우에는 무수석고와 베타형 반수석고가 생성되지 않도록 습식분위기를 충분히 유지시키는 것이 필요하다. When the dehydrated gypsum is dehydrated by microwave alone in the dry condition of atmospheric pressure, beta-type hemihydrate gypsum is formed rather than alpha-type hemihydrate gypsum. Therefore, when irradiating microwaves, it is necessary to maintain a wet atmosphere sufficiently so that anhydrous gypsum and beta-type hemihydrate gypsum are not produced.

본 발명은 가압반응기(autoclave)에 마이크로파 발생 장치를 부착하여 스팀에 의한 반응과 마이크로파에 의한 동시반응을 유도함으로써 탈황석고의 용해-재석출 반응에 의한 알파형 반수석고의 반응시간을 단축시켜 종래의 가압수증기법의 단점인 장시간의 반응시간에 따른 제조비용을 대폭 감소시킬 수 있는 마이크로파를 이용한 배연탈황석고로부터 알파형 반수석고를 제조하는 방법을 제공하는데 그 목적이 있다.According to the present invention, a microwave generator is attached to an autoclave to induce simultaneous reaction by steam and microwave to shorten the reaction time of alpha-semi-hydrated gypsum by dissolution-reprecipitation reaction of desulfurized gypsum. It is an object of the present invention to provide a method for producing alpha-type hemihydrate gypsum from flue gas desulfurization gypsum using microwaves which can significantly reduce the manufacturing cost according to a long reaction time, which is a disadvantage of the pressurized steam method.

또한, 본 발명은 반응이 끝난 후 마이크로파의 세기를 조절하여 생성물을 건조시킬 수 있기 때문에 별도의 건조설비가 불필요하며 효율적으로 건조가 가능한 마이크로파를 이용한 배연탈황석고로부터 알파형 반수석고를 제조하는 방법을 제공하는데 그 목적이 있다. In addition, since the present invention can dry the product by controlling the intensity of the microwave after the reaction is completed, there is no need for a separate drying equipment, and a method for producing alpha-type hemihydrate gypsum from flue gas desulfurized gypsum using microwaves that can be dried efficiently The purpose is to provide.

본 발명은 배연탈황석고를 알파형 반수석고로 전이시키기 위한 수열합성방법에 있어서, 일정량의 수분 및 첨가제를 함유하는 배연탈황석고의 성형체를 30 내지 40kgf/㎠의 성형 압력 하에서 10 내지 15중량%의 함수율을 갖도록 제조하여 가압반응기에 넣는 단계; 상기 가압반응기에 설치되어 있는 마이크로파 조사장치로부터 마이크로파를 조사하여 알파형 반수석고를 제조하는 단계; 및 상기 생성된 알파형 반수석고를 마이크로파로 건조시키는 것을 특징으로 한다. In the hydrothermal synthesis method for transferring the flue gas desulfurized gypsum to alpha-type hemihydrate gypsum, the molded body of flue gas desulfurized gypsum containing a certain amount of water and additives under a forming pressure of 30 to 40 kg f / ㎠ 10 to 15% by weight Preparing to have a water content of and putting it in a pressurized reactor; Preparing an alpha-type hemihydrate gypsum by irradiating microwaves from a microwave irradiation device installed in the pressure reactor; And drying the produced alpha-type hemihydrate gypsum with microwaves.

이와 같은 본 발명을 첨부한 도면에 의거하여 더욱 상세히 설명하면 다음과 같다.When described in more detail based on the accompanying drawings of the present invention as follows.

첨부 도면 중 도 1은 본 발명에 따른 스팀과 마이크로파를 이용하여 알파형 반수석고를 제조하는 시스템의 구성도를 나타낸 것으로, 먼저 배연탈황석고 저장조(1)로부터 일정량의 석고를 탈황석고 이송장치(2)를 통해서 혼합기(3)에 넣고 필요한 경우 첨가제 저장조(5)로부터 첨가제로서 0.5 ~ 2 중량% 농도의 숙신산나트륨(C4H4Na2O4)을 첨가제 이송장치(4)를 통해서 첨가하여 혼합한다. 이때 혼합물의 함수율을 10 ~ 15 중량%로 유지하는 것이 중요하다. In the accompanying drawings, Figure 1 shows a block diagram of a system for producing alpha-type hemihydrate gypsum using steam and microwaves in accordance with the present invention, first a desulfurized gypsum transfer device for a certain amount of gypsum from the flue gas desulfurization gypsum reservoir (2) And add sodium succinate (C 4 H 4 Na 2 O 4 ) at a concentration of 0.5 to 2% by weight as additives from the additive reservoir (5) through the additive feeder (4), if necessary. do. At this time, it is important to maintain the water content of the mixture at 10 to 15% by weight.

여기에 필요한 경우 종결정(Seed crystal)으로 미리 제조한 알파형 반수석고를 넣어도 좋다. 알파형 반수석고의 첨가량은 5 ~ 10 중량%가 적당하다. 첨가제인 0.5 ~ 2 중량% 농도의 숙신산나트륨(C4H4Na2O4)은 반응생성물인 알파형 반수석고가 침상으로 전이하는 것을 방지하고 결정형상을 주상으로 바꾸어주는 역할을 한다. If necessary, alpha-type hemihydrate gypsum prepared in advance with seed crystals may be added. The amount of alpha-type hemihydrate gypsum is preferably 5 to 10% by weight. Sodium succinate (C 4 H 4 Na 2 O 4 ) in the concentration of 0.5 ~ 2% by weight as an additive prevents the transfer of the alpha-type hemihydrate gypsum to the needle bed and serves to change the crystal form into the main phase.

이렇게 해서 준비된 혼합물을 압력성형기(6)에 넣고 일정한 압력으로 성형체를 제조한다. 이때 성형체의 압력은 30 ~ 40kgf/cm2로 유지하는 것이 바람직하다. 이보다 더 높은 압력으로 성형체를 제조하면 반응도중 성형체가 깨질 가능성이 높으며, 이보다 더 낮은 압력으로 성형체를 제조하면 성형체가 쉽게 부서지는 단점이 있다.
배연탈황석고를 일정한 압력이상으로 성형하는 이유는 성형체 내에 닫힌 기공(Closed pore)을 형성시키기 위한 것으로서 성형체에 마이크로파를 조사하면 닫힌 기공내의 수분의 온도상승으로 인해 성형체 내부의 기공 즉 성형체의 내부를 알파형 석고의 생성 조건인 포화수증기압 상태로 유도하기 위한 것이다.Thus prepared mixture is put into a pressure molding machine (6) to produce a molded body at a constant pressure. At this time, the pressure of the molded body is preferably maintained at 30 ~ 40kg f / cm 2 . If the molded article is manufactured at a higher pressure than this, the molded article is likely to be broken during the reaction. If the molded article is manufactured at a lower pressure, the molded article is easily broken.
The reason why the flue gas desulfurization gypsum is formed above a certain pressure is to form closed pores in the molded body. When the microwave is irradiated to the molded body, the pores inside the molded body, i.e., the inside of the molded body, are raised due to the temperature rise of moisture in the closed pores. It is for inducing to the saturated steam pressure state which is a production condition of mold plaster.

성형체가 제조되면 성형체를 운반대(7)에 일정한 높이로 쌓고 운반대를 마이크로파를 조사할 수 있는 가압반응기(8)에 넣는다. 다음에 가압반응기에 스팀을 넣어 가압반응기의 내부 온도를 일정온도±1℃로 유지시킨다. 이때 가압반응기의 압력은 포화수증기압으로 유지된다. 반응시 일정온도는 120 ~ 135℃의 범위를 벗어나지 않도록 한다. 일정시간이 지난 후 성형체 내부의 온도가 일정온도인 120 ~ 135℃보다 1 ~ 3℃ 높게 유지되도록 단속적으로 마이크로파를 조사한다. 약 1시간의 반응 후 스팀의 공급을 중단하고 반응기내의 스팀을 배출한 후 성형체 내부의 온도가 약 105℃를 유지하는 조건으로 마이크로파를 조사하여 건조를 실시하였다. 건조시간은 약 20분 정도가 적당하였다. 건조가 끝난 후 생성물은 분쇄기(9)에서 분쇄한 후 저장조(10)에 보관한다. When the molded body is manufactured, the molded body is stacked on the carrier 7 at a constant height and the carrier is placed in a pressurized reactor 8 capable of irradiating microwaves. Then, steam is put in the pressure reactor to maintain the internal temperature of the pressure reactor at a constant temperature ± 1 ℃. At this time, the pressure of the pressure reactor is maintained at the saturated steam pressure. During the reaction, the constant temperature should not be out of the range of 120 ~ 135 ℃. After a certain time, microwaves are intermittently irradiated so that the temperature inside the molded body is maintained at 1 to 3 ° C higher than the constant temperature of 120 to 135 ° C. After the reaction of about 1 hour, the supply of steam was stopped, the steam in the reactor was discharged, and drying was performed by irradiating microwaves under the condition that the temperature inside the molded body was maintained at about 105 ° C. The drying time was about 20 minutes. After the drying is finished, the product is ground in a grinder (9) and stored in a storage tank (10).

이렇게 해서 얻어진 생성물은 DSC에 의해 알파형 반수석고임이 확인되었다. The product thus obtained was confirmed to be alpha-type hemihydrate gypsum by DSC.

첨부 도면 중 도 2는 상기한 방법으로 제조된 본 발명에 따른 알파형 반수석고의 표면 상태를 촬영한 시차주사현미경(SEM) 사진이고, 도 3은 알파형 반수석고 시료에 대한 열적 흐름 특성을 분석한 DSC(Differential Scanning Calorimeter) 그래프이다.2 is a differential scanning microscope (SEM) photograph of the surface state of the alpha-type hemihydrate gypsum according to the present invention prepared by the above method, Figure 3 is a thermal flow characteristic analysis for the alpha-type hemihydrate gypsum sample One differential scanning calorimeter (DSC) graph.

본 발명에 따른 마이크로파를 이용한 배연탈황석고로부터 알파형 반수석고를 제조하는 방법은 기존의 가압수증기법을 이용하는 가압반응기(Autoclave)에 마이크로파를 조사할 수 있도록 하여 알파형 반수석고의 생성시간을 단축시킬 수 있을 뿐 만 아니라 반응 종료 후 생성된 알파형 반수석고를 가압반응기에 부착되어 있는 마이크로파만으로 건조시킴으로써 에너지 효율을 높여 알파형 반수석고의 제조비용을 낮출 수 있도록 한 것이 특징이다.The method for producing alpha-type hemihydrate gypsum from the flue gas desulfurization gypsum using microwaves according to the present invention can reduce the production time of alpha-type hemihydrate gypsum by allowing microwaves to be irradiated to the autoclave using the conventional pressurized steam method. In addition, it is possible to reduce the production cost of alpha-type hemihydrate gypsum by increasing energy efficiency by drying only the alpha-type hemihydrate gypsum produced after the reaction is finished with microwaves attached to the pressure reactor.

Claims (5)

습식 배연탈황석고에 마이크로파를 조사하여 알파형 반수석고를 제조하는 방법에 있어서, 함수율이 10 내지 15중량%이고, 첨가제로서 0.5 내지 2중량% 농도의 숙신산나트륨을 함유하는 상기 습식 배연탈황석고를 30 내지 40 Kgf/㎠의 성형압력하에서 성형체를 제조하고, 가압반응기 내에서 상기 성형체에 스팀을 가하여 120 내지 135℃의 온도를 유지하면서 포화수증기압 상태로 유지한 후, 상기 온도보다 1 내지 3℃ 높게 유지되도록 단속적으로 마이크로파를 조사하고, 다시 마이크로파를 이용하여 약 105℃의 온도에서 약 20분 동안 건조 및 분쇄시켜서 제조하는 것을 특징으로 하는 마이크로파를 이용한 배연탈황석고로부터 알파형 반수석고를 제조하는 방법.In the method for producing alpha-type hemihydrate gypsum by irradiating microwave to wet flue gas desulfurization gypsum, the wet flue gas desulfurization gypsum containing 30 to 15% by weight of water and containing 0.5 to 2% by weight of sodium succinate as an additive To a molded product under a forming pressure of 40 to 40 Kg f / cm 2, and steam is applied to the molded body in a pressurized reactor to maintain a saturated steam pressure while maintaining a temperature of 120 to 135 ° C., and then 1 to 3 ° C. higher than the temperature. Method for producing alpha-type hemihydrate gypsum from flue gas desulfurized gypsum using microwave, characterized in that the microwave is irradiated intermittently to be maintained, and dried and pulverized for about 20 minutes at a temperature of about 105 ℃ using microwave again. 제 1항에 있어서, 상기 성형체의 제조 시에 종결정으로 미리 제조한 알파형 반수석고를 5 내지 10중량%로 첨가하는 것을 특징으로 하는 마이크로파를 이용한 배연탈황석고로부터 알파형 반수석고를 제조하는 방법.The method for producing alpha-type hemihydrate gypsum from flue gas desulfurized gypsum using microwaves according to claim 1, wherein an alpha-type hemihydrate gypsum prepared by seed crystals is added at 5 to 10% by weight at the time of manufacturing the molded body. . 삭제delete 삭제delete 삭제delete
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Publication number Priority date Publication date Assignee Title
KR100920255B1 (en) * 2007-12-17 2009-10-05 한국지질자원연구원 Method for drying gypsum microwave
KR101155091B1 (en) 2010-08-17 2012-06-11 한국지질자원연구원 Method of adsorbing cadmium using waste calcium carbonate obtained from carbonation reaction of flue gas desulfurization (fgd) gypsum

Citations (1)

* Cited by examiner, † Cited by third party
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KR19990054430A (en) * 1997-12-26 1999-07-15 이구택 Device for manufacturing alpha-type hemihydrate gypsum of flue gas desulfurization waste absorbent

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR19990054430A (en) * 1997-12-26 1999-07-15 이구택 Device for manufacturing alpha-type hemihydrate gypsum of flue gas desulfurization waste absorbent

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
1019990054430 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100920255B1 (en) * 2007-12-17 2009-10-05 한국지질자원연구원 Method for drying gypsum microwave
KR101155091B1 (en) 2010-08-17 2012-06-11 한국지질자원연구원 Method of adsorbing cadmium using waste calcium carbonate obtained from carbonation reaction of flue gas desulfurization (fgd) gypsum

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