가스분사형 반응기에서 HCl가스가 석회석 슬러리의 탈황반응에 미치는 영향

유경선; 김경태

HWAHAK KONGHAK, Vol.36, No.5, 641-645, October, 1998

Export Citation

가스분사형 반응기에서 HCl가스가 석회석 슬러리의 탈황반응에 미치는 영향

Effect of HCl Gas on Sulfation Reaction of Limestone Slurry in a Jet Bubbling Reactor

유경선, 김경태

초록

가스분사형 반응기에서 HCI가스의 존재가 SO₂ 제거효율과 생성된 석고입자의 특성에 미치는 영향을 분석하였다. HCI 가스의 존재는 SO₂ 제거효율을 감소시켰으며 이는 HCI가스의 흡수에 의하여 생성된 Cl^- 이온에 의하여 SO₂가스의 수화반응 평형상수가 감소하였기 때문이다. 분산관의 압력손실 90mmAq이하에서 SO₂제거효율은 급격하게 감소한 반면 HCl 가스의 제거효율은 압력손실 50mmAq까지 유지되었으며 이는 HCl가스의 제거속도가 SO₂가스의 제거속도보다 매우 빠르기 때문이다. CaCl₂를 이용하여 슬러리내의 Cl ^-1이온농도를 증가시키면 SO₂제거효율은 Cl^-1 이온농도 10-30g/ι영역에서 최대값을 보인 후 완만히 감소하였다. HCl가스의 농도를 증가시키면 500ppm영역에서 최대의 SO₂제거효율이 나타났다. HCl가스를 이용한 경우 CaCl₂보다 낮은 액상의 Cl^-1이온농도에서 SO₂제거효율의 감소가 일어나며 이것은 가스상의 HCl흡수에 의하여 생성된 Cl^{- 1}이온농도가 벌크상보다 계면에서 높게 나타나기 때문이라고 사료된다. HCl가스가 존재하여도 생성된 입자는 석고로 확인되었으며 HCl가스의 농도가 증가할수록 석고결정의 크기는 감소하였다

Effect of the Presence of HCl gas on the SO₂ removal efficiency and the characteristics of gypsum crystal formation has been investigated in a jet bubbling reactor. The presence of HCl gas reduces the SO₂ removal efficiency, which results from the decrease of equilibrium constant of SO₂ hydrolysis reaction by the production of Cl^-1 ions with absorbing HCl gas.SO₂ removal efficiency decreases rapidly below the pressure drop of 90 mmAq in the sparger, while HCl gas removal efficiency is sustained up to ,50 mmAq because the removal rate of HCl gas is more faster than that of SO₂. When the concentration of Cl^-1ions is augmented using CaC1₂, SO₂ removal efficiency shows maximum value at about 10-30g/ι and then decreases gradually. Maximum SO₂ removal efficiency appears at the concentration of about 500 ppm by the increase of HCl gas. The decrease of SO₂ removal efficiency using HCl gas occurs at lower concentration of Cl ^-1 ions than using CaCl₂, which might implicate that concentration of Cl^-1ions at the gas-liquid interface is higher than that in bulk Phase. The Product Particles are identified as gypsum in spite of the presence of HCl gas and the size of gypsum crystal decreases with increasing the concentration of HCl gas.

Keywords:FGD;HCl;Gypsum;CaCl₂;Gas-Liquid Mass Transfer;Limestone Slurry

[References]

Kohl AL, Riesenfield FC, "Gas Purification," 4th ed., Gulf Publishing Co., Houston (1985)
Yoo KS, Kim SD, Park SB, Ind. Eng. Chem. Res., 33(7), 1786 (1994)
Yoo KS, Jeong SM, Kim SD, Park SB, Ind. Eng. Chem. Res., 35(5), 1543 (1996)
Lim YI, Yoo KS, Jeong SM, Kim SD, Lee JB, Choi BS, HWAHAK KONGHAK, 35(1), 83 (1997)
Chu KJ, Yoo KS, Kim KT, Mater. Res. Bull., 32(2), 197 (1997)
EPRI Report "Evaluation of the Chiyoda Thoroughbred 121 Flue Gas Desulfurization Process at the University if Illinois Abbott Plant," (1990)
Toprac AJ, Rochelle GT, Environ. Prog., 1, 52 (1982)
Rosenberg HS, Ind. Eng. Chem. Prod. Res. Dev., 25, 348 (1986)
Boynton RS, Chemistry and Technology of Lime and Limestone, 2nd ed., John Wiley & Sons, Inc., New York, pp. 228-359 (1980)
Yoo KS, Song BH, Kim SD, Kim KT, J. Korea Solid Waste Eng. Soc., 14, 403 (1997)
Choi BS, Park SS, Kim YW, J. Korean Ind. Eng. Chem., 5(5), 836 (1994)
Chan PK, Rochelle GT, EPA/EPRI Symposium on Flue Gas Desulfurization, NewOrlenas, November 1-4 (1983)
Bjerle I, Bengtsson S, Farnkvist K, Chem. Eng. Sci., 27, 1853 (1972)
Wallin M, Bjerle I, Chem. Eng. Sci., 44, 61 (1989)
Noblett JG, The 1991 SO2 Control Symposium, Washington, D.C., December 3-6 (1991)
Jarvis JB, Trofe TW, Stewart DA, EPA/EPRI Symposium on Flue Gas Desulfurization, New Orleans, November 1-4 (1983)
Chen PC, Tai CY, Shih SM, J. Cryst. Growth, 123, 277 (1992)
Tseng PC, Rochelle GT, Environ. Prog., 5, 5 (1986)

[1] Kohl AL, Riesenfield FC, "Gas Purification," 4th ed., Gulf Publishing Co., Houston (1985)

[2] Yoo KS, Kim SD, Park SB, Ind. Eng. Chem. Res., 33(7), 1786 (1994)

[3] Yoo KS, Jeong SM, Kim SD, Park SB, Ind. Eng. Chem. Res., 35(5), 1543 (1996)

[4] Lim YI, Yoo KS, Jeong SM, Kim SD, Lee JB, Choi BS, HWAHAK KONGHAK, 35(1), 83 (1997)

[5] Chu KJ, Yoo KS, Kim KT, Mater. Res. Bull., 32(2), 197 (1997)

[6] EPRI Report "Evaluation of the Chiyoda Thoroughbred 121 Flue Gas Desulfurization Process at the University if Illinois Abbott Plant," (1990)

[7] Toprac AJ, Rochelle GT, Environ. Prog., 1, 52 (1982)

[8] Rosenberg HS, Ind. Eng. Chem. Prod. Res. Dev., 25, 348 (1986)

[9] Boynton RS, Chemistry and Technology of Lime and Limestone, 2nd ed., John Wiley & Sons, Inc., New York, pp. 228-359 (1980)

[10] Yoo KS, Song BH, Kim SD, Kim KT, J. Korea Solid Waste Eng. Soc., 14, 403 (1997)

[11] Choi BS, Park SS, Kim YW, J. Korean Ind. Eng. Chem., 5(5), 836 (1994)

[12] Chan PK, Rochelle GT, EPA/EPRI Symposium on Flue Gas Desulfurization, NewOrlenas, November 1-4 (1983)

[13] Bjerle I, Bengtsson S, Farnkvist K, Chem. Eng. Sci., 27, 1853 (1972)

[14] Wallin M, Bjerle I, Chem. Eng. Sci., 44, 61 (1989)

[15] Noblett JG, The 1991 SO2 Control Symposium, Washington, D.C., December 3-6 (1991)

[16] Jarvis JB, Trofe TW, Stewart DA, EPA/EPRI Symposium on Flue Gas Desulfurization, New Orleans, November 1-4 (1983)

[17] Chen PC, Tai CY, Shih SM, J. Cryst. Growth, 123, 277 (1992)

[18] Tseng PC, Rochelle GT, Environ. Prog., 5, 5 (1986)