Research and Application of High Flow and High Temperature Concentrated Sulfuric Acid Circulation Pump

Abstract: With the development of domestic phosphate compound fertilizer and non-ferrous metal smelting enterprises and the more stringent environmental protection requirements, more and more large-scale sulfur and flue gas sulfuric acid plants are under construction or are about to be built. As the contact method sulfuric acid plant key equipment - vertical high temperature sulfuric acid circulating pump, the majority of large flow models rely on imports, Kunming Jia and Pump Co., Ltd. using advanced materials and technology has been successfully developed and produced high-volume high-temperature concentrated sulfuric acid cycle Pumps, Guixi Smelter in Jiangxi Copper, Yunnan Tricyclic Company, Yunnan Fu Rui companies, Gansu Jinchuan Nonferrous Metals Group, Zhejiang Jiahua use.

Key words: large scale flue gas, acid, vertical high temperature, concentrated sulfuric acid circulating pump, practical application

1 Introduction

In the late 1980s, as one of the key equipment in the contact sulfuric acid plant, the dry and suction tower high-temperature concentrated sulfuric acid circulation pump has basically achieved its localization. So far in large and medium-sized sulfuric acid plant, the vast majority of dry and suction tower high-temperature concentrated sulfuric acid circulating pump (flow rate of 1000m3 / h or less) have been using domestic equipment, only a few large-scale flue gas acid plant and by foreign contractor In the import is still used dry, suction tower high temperature concentrated sulfuric acid circulating pump.

With the sulfur and phosphorus chemical companies and non-ferrous metal smelting enterprises bigger and stronger requirements, the domestic sulfuric acid plant tends to large-scale and oversized (800kt / a or more). In the process of optimizing the sulfuric acid process, in addition to the traditional three-tank and three-pump three-column circulation mode, more two-tank two-pump three-tower, one-tank two-pump three-tower and even one-tank-one pump three-tower circulation mode are used more now. This high temperature concentrated sulfuric acid circulation pump flow and reliability put forward higher requirements.

Based on the needs of the market, Kunming Jiahe Pump Co., Ltd. constantly innovates and absorbs the advanced experience of foreign concentrated sulfuric acid pumps. Based on the design and production experience of high-temperature concentrated sulfuric acid pumps for many years, we have successfully developed and produced large-flow 1200m3 / h and 1400m3 / h High-temperature concentrated sulfuric acid pump based on its own design and trial production jhb2000-26 high-temperature concentrated sulfuric acid pump, the flow of 2000m3 / h, head 26m, to meet the large-scale production of sulfuric acid plant cycle requirements.

The following high-flow high-temperature sulfuric acid circulating pump in all aspects of the situation for a brief introduction.

2, material characteristics

Materials in reference to foreign advanced high-temperature sulfuric acid pump advanced materials technology, self-developed nickel-based austenitic stainless steel jsb-11 alloy, used in the manufacture of impeller, bushings, bushings, seal ring. This is a special alloy developed for high temperature concentrated sulfuric acid pump, after heat treatment hardened to make it rise from cloth hardness 225 to cloth hardness 500 without reducing its corrosion resistance, with strong resistance to erosion and erosion erosion Performance, up to 140 ° C in 98% h2so4 and 100 ° C even in 93% h2so4, with annual corrosion rates (static coupons) below 0.02 mm / a in both cases.

Jiahe latest development of jsb-1, jsb-2 new alloy ductile iron, due to the addition of the original alloy composition, nickel, chromium added to improve its corrosion resistance in sulfuric acid, adding copper, molybdenum and rare earth to improve the metallurgical Structure, grain refinement, increased resistance to pitting. The formation of dense feso4 • crso4 colloids in high temperature concentrated sulfuric acid resulted in the formation of a stable, purified membrane that retarded the corrosion of sulfuric acid.

Shaft made with jsb-1, after the special heat treatment after the ball, with good strength and corrosion resistance, due to the alloy itself already has a good anti-corrosion properties, the abolition of the traditional axis of the package Teflon , So maintenance, processing, transportation more convenient. jsb-2 is used to make the pump body, the center take over and the liquid pipe and so on.

3, the structural features In the structure of the form, in the first generation of high-temperature high-temperature concentrated sulfuric acid circulating pump based on the second generation of new design, improve pump reliability and improve pump efficiency.

a, followed the traditional advantages of jhb vertical high temperature concentrated sulfuric acid pump structure, the use of six-motor drive, compact structure, full account of the hydraulic model in the design of the NPSH, the efficiency of the pump can be as high as 80%, the pump operation Smooth, reduce energy consumption.

b. According to the design requirement of the horizontal circulation groove, extend the distance from the bottom of the pump to the center line of the impeller to 1900mm ~ 2100mm. After the suction pipe is installed, the depth of the total liquid can reach 3300mm, meeting the technical requirements of production technology.

c, the use of symmetrical double-volute shell structure design to reduce the radial load on the plain bearings to extend the service life of plain bearings.

d, improve the installation and positioning to take over to make the operation easier and more convenient to maintain.

4, the actual use

a, so far, Kunming Jia and Pump Company designed and manufactured the maximum flow of high-temperature concentrated sulfuric acid pump jhb1400-22, flow 1400m3 / h, head 22m, the pump floor to the impeller centerline distance 1900mm, Jiangxi Copper Group Guixi Sulfuric acid sulfuric acid smelting tower circulation tank on a system for six months, with the original plant in Japan imported 6000v, 200kw six-motor drive, put into use without maintenance. Pump performance fully meet the process requirements of the system, the pump vibration value in operation to meet the standard requirements, fix the visual inspection without any corrosion.

b, the largest sulfur acid plant has been driving the system, Yunnan Chemical Industry, Chemical Engineering, 600kt / a absorption tower circulating pump (one or two absorption tower shared) jhb1250-28, flow 1250m3 / h, lift 28m, has been running for one year More than enough to fully meet the technical requirements of the device.

c, Zhejiang Jiahua 300kt / a sulfur acid plant, the choice of a tank and a pump three-tower cycle, circulating pump jhb1100-40, flow 1100m3 / h, lift 40m, run almost six months, fully able to meet the device technology Claim.

d, Yunnan Furui Chemical 800kt / a sulfur acid plant, the choice of three-tank three-pump three-loop cycle, each circulating pump is jhb1300-30, flow 1300m3 / h, lift 30m, stand-alone commissioning normal.

e, Jinchuan Nonferrous Metals Company chemical plant 570kt / a copper smelter acid plant, the choice of three tanks and three pumps three-loop cycle, each circulating pump is jhb1250-30, flow 1250m3 / h, lift 30m, has been shipped to The scene, is installing and debugging.

5 Conclusion

As the largest supplier of high temperature concentrated sulfuric acid pump design and production in China, Jiahe Company devotes itself to the development of large-scale key pump equipment. With excellent product quality and considerate and timely after-sales service, Jiahe Company makes localization for key equipment of domestic large-scale and ultra-large sulfuric acid plant Greater contribution.