Phosphoric acid slurry pump is mainly used in the delivery of phosphate slurry media, is one of the key pump device can be used vertical or horizontal, vertical pump assembled in the extraction Ye above the tank. Following Xiaobian share with you about phosphate slurry pump overview. Phosphate slurry pump Overview 1. Operating characteristics (1) Dihydrate phosphate plant transport medium Dihydrate phosphate slurry Solid phosphogypsum (the main component of CaS04.2H2O and undecomposed phosphate and acid insoluble). 25% -32% P2O5 20% -30%; free sulfuric acid H2S041% --- 4%; fluorosilicic acid H2SiF61% -3%; chloride Cl- slight viscosity 5-15 mPa.S density Slurry) 1.3 ~ 1.5t / m3 Medium temperature 70 ~ 85 ℃ (2) semi-aqueous phosphoric acid plant Semi-aqueous phosphoric acid plant operating conditions and dihydrate phosphoric acid plant is the main difference between the liquid phosphoric acid concentration and The reaction temperature is higher, the specific data are as follows: liquid phosphoric acid P20540% ~ 48%; reaction temperature 95 ~ 105 ℃ The medium is under vigorous stirring conditions. 2. Selection requirements Phosphate slurry pump selection requirements are mainly based on mixing medium and the reaction tank, the choice of corrosion resistance and wear resistance of the pump over-current components and materials of a reasonable structure of the vertical pump. (1) Material selection of pump overcurrent parts The corrosion resistance of ultra-low carbon molybdenum di-titanium and molybdenum tri-titanium is good under the condition of phosphoric acid medium (solid content less than 3%), but the phosphoric acid slurry % ~ 35%) conditions, severe wear and tear, shortened service life. Therefore, pay particular attention to media and operating conditions when selecting pump overcurrent component materials. ①medium temperature pump over-current component corrosion rate increases with temperature. For example, the extraction phosphoric acid temperature from 70 ℃ to 85 ℃, the corrosion rate doubled. Therefore, the selection of materials to pay attention to the temperature. ② phosphoric acid concentration increased phosphoric acid concentration, increased corrosion. For example, molybdenum tri-titanium stainless steel is corrosion-resistant in the dihydrate phosphoric acid production, but in semi-aqueous phosphoric acid, when used in a reaction-tank stirred shaft bushing, 85% of NN is pyramidal in only one month Pupil pupil 3. . Therefore, the dihydrate phosphate reaction tank vertical pump overcurrent components recommended CD a 4MCu; Z3CNUD26-05; Chromium 30 (F30% CrM0 and FCr30) alloy; half-water phosphoric acid production pump over-current components recommended chromium 30 (F30% CrM0 and FCr30) alloys; J-1 alloys; F5 alloys; SaniCr028; Hastelloy C. (2) the choice of pump speed Pump speed increases, will accelerate the impeller and volute overcurrent components such as erosion and corrosion. According to the foreign countries and the phosphate fertilizer plant in Yunnan phosphate fertilizer plant in the 1970s the introduction of phosphoric acid plant pump speed, the vast majority of 970 and 1460r / min (the former more), but not as high as 2900r / min speed. Therefore, to meet the flow, lift the premise, try to choose low-speed pump. (3) the choice of vertical pumps and horizontal pumps Before the 1980s, China's phosphate ammonium phosphate plant pumps, almost all vertical pumps. Due to the prevailing conditions, the domestic horizontal shaft pump leak serious. At present, many domestic horizontal pump sealing technology has been greatly improved. Horizontal packing used to seal, agreed that the carbon fiber pump. The pump flow and lift provided by the pump manufacturer are data obtained from the performance test of water as the medium. When the pump is used, the performance should be converted according to the viscosity and solid content of the process medium. Therefore, the actual selection of the pump factory sample flow rate of 800 ~ 900m3 / h, lift 8-9m circulation pump is appropriate. Flow selection is also not necessary too large, which will increase energy consumption and will accelerate the wear and tear of the media on the heat transfer tube wall. Filler use more reliable. Compared with the vertical pump, the horizontal pump also has the following advantages: ①horizontal pump price is low, usually the same flow, head pump vertical field conditions, and even ¼. ② vertical pump support frame cantilever shaft length is limited, often to the production control level to bring trouble. If the vertical pump can not be installed directly on a large tank (such as phosphate finished storage tank), the media must be led to the small tank of the vertical pump by opening the side of the lower tank, which increases the investment and sometimes prevents "Empty" or "full slot", but also one more operating workers. (4) Selection of pump impeller type Since phosphoric acid, phosphoric acid slurry and ammonium phosphate slurry contain solid particles, together with sodium, potassium and impurities such as iron, aluminum and magnesium brought by phosphate rock, especially sodium, Potassium) In the production of phosphoric acid will produce sodium fluoride and potassium silicate, dissolved in phosphoric acid. As the temperature drops, solubility decreases and precipitates, making it easy to form a hard scale on the pump impellers, especially the volute (these foulants are also intermingled with other solids such as calcium sulfate). Therefore, in the phosphate ammonium phosphate plant, generally use open impeller, especially in the phosphate plant reaction tank and phosphate filtration system, we must choose the open impeller; ammonium phosphate slurry pump also use open impeller. For example, Dalian Pump Factory vertical pump manufacturing, TCF-type open impeller for phosphate slurry media; and TCN-type closed impeller can not be used for phosphate slurry media. Furthermore, experience has shown that the lower part of the vertical pump for slurry can not be set under the bearings. 3. Structure characteristics of phosphate slurry pump and product status at home and abroad Phosphoric acid slurry pump are vertical, single stage, single suction cantilevered submerged pump, base, the liquid pipe separated from the cylindrical tube, without shaft seal. Pump shaft in the liquid part of the bearing does not set to accommodate the transport of solids containing media. The depth of the pump immersion medium can be 700-2000mm, if necessary, can also be installed in the suction inlet pump. FYL type, YPL type, LYA type pump structure and TCF similar. Selection requirements Pump over-current component material can refer to or slightly lower than the phosphor slurry pump over-current components of the material requirements, the selection of phosphate slurry slurry pump more use 0Cr18Nil2M02Ti, phosphate circulation pump can also be 0Cr18Ni12M02Ti, but the choice of CD-4MnCu it is good. The selection of circulating pump focus on the following issues. (1) As the circulating pump is a large flow, low lift horizontal pump, shaft seal at the general use of cooling water, it is necessary to pay attention to shaft seal without slurry leakage, but also to prevent the cooling water into the media system. (2) When the system stops in an emergency, the pump will also stop. Pay attention to no slurry leakage at the pump shaft seal when the evaporation system is not discharging. (3) In the case of unfavorable conditions of the concentrated evaporation system, such as high heating steam pressure, high slurry concentration or low liquid level, the actual flow of the circulating pump is much lower than the rated flow of the pump, which requires the pump to have good resistance Cavitation performance. (4) According to the process of calculating the flow and lift, choose the appropriate flow, lift the pump. For example, 30,000 tons / year slurry APM universal design of 25% -40% aqueous ammonium phosphate slurry medium selection flow 800m3 / h, head of the mixed flow pump 8m or axial flow. Further reading: Motor IFAT China's top ten brands Guangzhou Exhibition building water pump manufacturers ranking ptc Show article belongs to Internet industry (Xiamen) Co., Ltd. All are welcome to reprint, please indicate the source and author of: Asian pumps Network Editor : Gogoing (QQ / wechat: 181817456) starting: http://beng.liuti.cn/ (service hotline: 400-6030-811)