KR800000897B1

KR800000897B1 - A method for removing fluorine from phosphoric acid and concentrating

Info

Publication number: KR800000897B1
Application number: KR7701986A
Authority: KR
Inventors: 임진성
Original assignee: 임진성
Priority date: 1977-08-25
Filing date: 1977-08-25
Publication date: 1980-09-10

Abstract

A method of defluorating a wet process phosphoric acid solution and simultaneously concentrating the solution having a P2O5 content of 41.9%, and F 1.68% by weight to a P2O5 content of 53.5% and F 0.41% by weight by the way of spraying said solution from the top of the tower to contact said soln. countercurrently with heat gas rising from the bottom in the acid-resisting filler packed in the middle of the tower, is described.

Description

Debulking concentration method of phosphoric acid

본 발명 공정의 일실시예시도.One embodiment of the process of the present invention.

본 발명은 인산의 농축과 탈불을 효과적으로 실시하기 위한 탑식농축법의 개량방법이다.The present invention is a method of improving the tower concentration method for effectively concentrating and defluorination of phosphoric acid.

종래의 인산 농축법으로서는 액중연소증발법, 수직관식 열교환기에 의한 진공농축방법, 탑식분무 증발방법 등이 있으며, 탑식인산 농축방법은 탑실내 공간에 상부에서 순환인산액을 고압분출시켜 완전 미스트 상태로 분사 낙하시키는 과정에서 하부로부터 상승되는 고온중유연소 열가스와 접촉교류하므로 서로 수분을 휘발시켜 농축하나 탑상부에서의 순환인산액을 완전 미스트상으로 분사하는 특수장치등이 필요하고 순환인산액을 미스트상태로 분사하기 때문에 상승가스와 더불어 비산 손실되는 인산량이 액 5%에 달하고 탑실내에서의 상승하는 고온가스와의 접촉시간이 짧은 관계상 인산의 농축효율과 탈불효율도 낮은 등의 문제등이 있었다.Conventional phosphoric acid concentration methods include submerged combustion evaporation method, vacuum concentration method using a vertical tube heat exchanger, tower spray evaporation method, and the like. In the process of injection dropping, it is in contact with hot gasoline combustion hot gas rising from the lower part, so it vaporizes and concentrates each other's water, but it requires special equipment to spray the circulating phosphate liquid from the top of the column to the complete mist phase. Due to the injection in the state, the phosphoric acid lost in scattering with the rising gas reached 5% of liquid and the contact time with the rising hot gas in the tower room was short. .

본원 발명인은 탑식분무농축 방법의 문제점을 검토 연구한 결과 탑실내에 Na₂O₂CaO3SiO₂의 조성으로 된 내산연화를 충진하고 순환인산액을 상부에서 액방울상태(液滴狀態)로 낙화시켜 순환인산액이 충진내산 연화표면에 액막(液幕)을 형성하도록 유하시킨 결과 순환인산액의 낙하시간과 상승열가스의 탑내 체류시간이 길어 상호 접축시간이 길어서 농축효과와 열효율이 향상되고 인산액의 미스트로 인한 비산 손실이 0.5%정도로 현저히 감소되며 하부에서 취입하는 열가스에 의하여 하부에서 발생된 증기와 열가스가 유하액 표면과 교류접축됨으로서 증기를 인산액 표면에 취입하는 결과가 되어 액증연소법, 열교환기를 이용한 진공농축법등 보다 탈불효과가 현저히 향상되며 보통 상압하에서 농축할때와 비교하여 실시예와 같이 통상보다 약 50℃정도 저온에서 농축을 행할 수 있어 장치의 수명을 연장하는 등의 여러가지 종래 어떤 방법보다도 현저한 효과를 얻을 수 있었다.The present inventors have studied the problems of the tower spray concentration method and found that the tower chamber was filled with acid softening resistant to Na ₂ O ₂ CaO ₃ SiO ₂ , and the circulating phosphate solution was dropped from the top to the droplet state. As a result of dropping the phosphate solution to form a liquid film on the surface of the acid-resistant softening, the dropping time of the circulating phosphate solution and the residence time of the rising heat gas were long, so that the contact time was long. The fugitive loss due to mist is significantly reduced to about 0.5%, and the steam and heat gas generated at the bottom are in contact with the surface of the dripping liquid by the heat gas blown from the bottom, resulting in the injection of steam to the surface of the phosphate solution. The de-fluorination effect is remarkably improved than the vacuum concentration method using a heat exchanger, and it is usually about 50 ° C. than usual as compared with the case of concentration under normal pressure. The concentrate can be performed at low temperatures, any number of conventional ways, such as to extend the life of the device than can be obtained a remarkable effect.

제1도는 본원 발명실시예시도로서 공정에 의하여 설명하면, 농축될 인산은 저장탱크(1)에 공급되어 폼푸(2)로 스프레이(3)에 보내진다. 스프레이(3)에서 유적(流滴)상태로 산포된 인산은 탑(4)을 유하하는 동안 충진물인 내산연화층(5)의 표면을 필림상으로 흐르게 되며 이때 하부로부터 상승하는 고온 연소가스와 접축하여 가온 증발된다.1 is illustrated by the process of the present invention, the phosphoric acid to be concentrated is supplied to the storage tank (1) and sent to the spray (3) to the foam (2). Phosphoric acid dispersed in the spray (3) in the oily state flows through the surface of the acid-resistant softening layer (5), which is a filling material, during the flow of the tower (4), and is in contact with the hot combustion gas rising from the bottom. On evaporate warmly.

증발된 가스는 파이프(6)을 통하여 벤츄리스크라바(7) 및 (8)을 통하는 동안 폼푸(11), (12)에 의하여 순환되는 냉각수(9),(10)에 의하여 불소(F)가 제거된 후 대기에 붕출된다.The evaporated gas is fluorine (F) by the cooling water (9), (10) circulated by the pompu (11), (12) while passing through the venturislava (7) and (8) through the pipe (6) It is removed and then dissipated to the atmosphere.

[실시예]EXAMPLE

습익인산(P₂O₅41.9% F1.68%)을 제1도 탑식농축 장치에 공급하여 P₂O₅53.5까지 농축한 결과 F는 0.41%, 농축 종료시의 온도 118℃, P₂O₅의 회수율 99.5%를 얻었다.Wet phosphate (P ₂ O ₅ 41.9% F1.68%) was fed to the first-column tower concentrator and concentrated to P ₂ O ₅ 53.5. F was 0.41%, the temperature at the end of concentration was 118 ° C and P ₂ O ₅ 99.5% recovery was obtained.

[본원방법의 효과비교][Comparison of Effects of the Original Method]

이상과 같이 본원 발명방법은 순환인산액을 종래의 분무식을 지양하고 액적상태로 하므로 종래와 같이 미스트 발생을 위한 특수시설이 불필요하고 충진내산연화 표면을 인산이 필림상으로 막을 지어 흐르므로 미스트 발생을 최대한 억제할 수 있고, 하부 고온부에서 발생된 미스트는 상승하면서 유하액에 다시 흡수되므로 미스트가 페가스와 같이 비산 손실되는 인산이 적어지므로 종래 방법에서 미스트로서 비산되는 인산손실이 5%이던 것이 본원방법에서는 0.5%로 억제할 수 있어 인산화수율이 99.5%에 이르며, 순환인산액이 내산연화표면을 필림상으로 유하하므로 체류시간이 길어 탑내의 열가스와의 접속시간이 길어져 농축효과와 열효율이 좋으며 따라서 종래 160℃에서 조업을 행하던 것을 비교적 저온인 110℃에서 행할 수 있고 탑하부에서 고온열가스에 의하여 발생되는 수증기와 열가스가 유하액 표면과 교류접축됨으로 접축표면적이 크고 접축시간이 길어져 탑불효과가 현저하게 향상된다.As described above, the method of the present invention avoids the conventional spray type and makes the droplet state, so that no special facility for generating mist is required as in the prior art, and mist is generated because the phosphoric acid flows through the filling film in the film. It can be suppressed as much as possible, because the mist generated in the lower portion of the hot portion rises again absorbed in the dripping liquid, so that less phosphoric acid is lost scattering, such as waste gas in the conventional method was 5% of the phosphoric acid loss scattered as mist in the conventional method In the method, it can be suppressed to 0.5%, the phosphorylation yield reaches 99.5%, and the circulating phosphate fluid flows down the surface of acid softening, so the residence time is long, so the connection time with the heat gas in the tower is long, so the concentration effect and thermal efficiency are good. Therefore, the conventional operation at 160 ℃ can be performed at a relatively low temperature 110 ℃ and high temperature heat at the bottom of the tower Doemeuro water vapor and heat exchange jeopchuk gas and liquid flows down the surface generated by the switch becomes longer, this large surface area jeopchuk jeopchuk time is improved considerably the tapbul effect.

Claims

A method of condensing phosphate decondensing in a column-type phosphoric acid concentration method, by filling acid-resistant fillers in a column, dispersing circulating phosphoric acid in the form of a droplet from the top, and emulsifying the filler phase in a liquid film state while performing AC-contact with heat gas.