What pumps are mainly used in power plant desulfurization? What are the consumables of these pumps?

Power plant desulfurization generally uses wet CaSO4 desulfurization, this desulfurization method is simple and common, mainly including: slurry circulation pump, gypsum slurry discharge pump, process water pump, mist eliminator flushing pump, limestone slurry pump, accident slurry pump, pit pump, ** water pump, pit pump in dehydration area, pit pump in pulping area, etc.; There are also oxidation fans, booster fans, water ring vacuum pumps for dewatering (not necessarily the same in each plant), various lubricating oil pumps, hydraulic oil pumps, and sealed fans. In terms of pump types, power plants mainly use centrifugal pumps, axial flow pumps, and piston pumps.

However, as far as desulfurization is concerned, centrifugal pumps and fans are basically axial flow. Because the axial flow pump cannot adapt to the actual requirements under various working conditions in the application, and the outlet pressure is relatively low under the same output; It is generally suitable for use when the flow rate is large but the pressure is low. So the pumps in power plants, unless there are special requirements, are centrifugal.

The fan generally uses axial flow Yes (the flow rate is large, and the pressure requirement is not high).

What are the consumables of the pump:

1. The pump casing is generally cast iron, which is prone to cracks due to mechanical force or thermal stress. When the pump is affected by cavitation during the work or does not release the water in the pump casing in winter and is frozen, it is also easy to rupture, if the damage is serious and cannot be repaired, the new pump casing should be replaced.

2. The pump shaft is generally made of carbon steel, but it is also easy to be damaged due to manufacturing quality, use or installation. Pump shafts may be subject to cracks, bending, journal wear, thread damage, etc., and may also cause fracture accidents. If the damage is serious and cannot be repaired, a new shaft should be replaced.

3. The impeller is an important working part of the pump, which is made of cast iron. It is also susceptible to damage due to manufacturing quality and use. The impeller may be cracked, the surface may form sockets or perforations due to cavitation, and the blades may be thinned or ecbrased by long-term erosion, or even crushed by debris.

Some flaws can be fixed; Some defects cannot be repaired, i.e. the impeller should be replaced with a new one.

4. The bearing of the sliding bearing is made of copper tin alloy, which has poor wear resistance and is one of the most vulnerable parts that are easy to wear and burn out. Rolling bearings generally have an average service life of 5,000 hours, but they are also prone to wear or damage due to improper installation, long service time or poor maintenance. In addition to the individual parts of the rolling bearing can be replaced with new ones, the whole parts should generally be replaced.

5. The mouth ring is also known as the leakage reduction or wear reduction ring, which is one of the most easily worn parts of the water pump. It can be repaired or replaced with a new one after wear. When replacing a new leakage reduction ring, its inner diameter should be configured according to the outer diameter of the impeller inlet.

If the outer diameter of the impeller inlet is worn, it can be turned to eliminate grooves and ellipses, and then equipped with a leakage reduction ring with a reduced inner diameter, and the outer diameter of the impeller inlet can generally be turned three times.

6. The filler will become hard and lose its elasticity after a long time, which will make the pump leak air and water, and the new filler should generally be replaced.

7. The oil seal is a rubber product, which is easy to wear and age, and generally needs to be replaced with new parts.

Generally, it is an ordinary horizontal desulfurization pump and a vertical pit pump, as well as a small number of clean water pumps, and the desulfurization pump is also divided into main circulation pump and small pump.

Wearing parts are generally overcurrent parts, divided into alloy and rubber materials, and mechanical seals are also relatively easy to damage.

Wet calcium method magnesium double base:

Slurry circulation pump: impeller, suction pipe, volute, machine seal.

Slurry addition pumps: impeller, volute, front and rear guards.

Gypsum discharge: impeller, volute, front and rear guards.

Filter vacuum pump: distribution plate, impeller.

Wet ammonia method: basically no wearing parts!

The pumps used in desulfurization are different due to different solid content, but they are basically slurry pumps, and the wearing parts are impellers and the like like other pumps.

1) Corrosion and wear-resistant, one pump is multi-purpose, and acid and alkali clear liquid slurry are applicable.

2) The pump body is a steel-lined ultra-high molecular weight polyethylene structure, the lining thickness is 8 20mm, the pump applies the patented technology of plastic lining, compared with other similar pumps, it has the advantages of good thermal deformation resistance of the lining layer, crack resistance, anti-falling off, and high service temperature.

3) There are two types of impellers: split type and closed type, which can be selected according to the condition of the medium.

4) Seal: K-type power seal, K1 type power seal, T-type packing seal, T1 type packing seal, C3 type non-standard seal.

5) Applicable medium: sulfuric acid with a concentration of less than 80%, nitric acid with a concentration of less than 50%, hydrochloric acid and liquid alkali of various concentrations, suitable for both clear liquid and slurry.

4. Main technical parameters: operating temperature -20 90 (using modified materials, it can be increased to more than 100), inlet diameter 32mm 350mm, flow rate 5 2600m3 h, head within 80m.

1) Phosphorus sulfate fertilizer industry: transportation of dilute acid, mother liquor, sewage, seawater, fluorosilicic acid containing silica gel, phosphoric acid slurry and other media.

2) Non-ferrous metal smelting industry: especially suitable for the transportation of various acids, corrosive slurries, slurry (with filter presses), electrolytes, sewage and other media such as lead, zinc, gold, silver, copper, manganese, cobalt, rare earth and other hydrometallurgy.

3) Chemical and other enterprises: all kinds of sulfuric acid, hydrochloric acid, alkaline, oil clear liquid or slurry positions. Production of titanium dioxide and iron red powder, production of various dyes and pigments, processing of non-metallic minerals and other industries.

4) Chlor-alkali industry: hydrochloric acid, liquid alkali, electrolyte, etc.

5) Water treatment industry: pure water, high-purity water, sewage (leather sewage, electroplating sewage, electronic sewage, papermaking sewage, textile sewage, food sewage, domestic sewage, pharmaceutical sewage, etc.).

6) Iron and steel enterprises: sulfuric acid, hydrochloric acid posts in pickling systems, sewage with impurities.

7) Wet semi-dry desulfurization circulating pump: It can be used for alkaline, acidic and corrosive positions at the same time.

8) Transportation of corrosive liquids and coal slurry in the coal industry and coal chemical industry; Coal washing and preparation with pumps.

1. Shaft seal part:

The packing shaft seal pump needs to regularly test the sealing water pressure and water volume, always keep a small amount of clean water flowing along the shaft, regularly adjust the packing gland, check and replace the packing regularly, and the shaft seal water pressure and water volume should meet the requirements of the shaft seal inspection.

2. Impeller part:

In order to make the pump run efficiently, the gap between the impeller and the front guard plate must be adjusted in time, the pump should be stopped first when adjusting the impeller clearance, the bolt of the compression bearing box should be loosened, the adjustment nut should be loosened, and the bearing assembly should move forward, and the shaft should be rotated by hand according to the rotation direction of the pump until the impeller and the front guard plate rub, and then the rotor should be moved back with the adjustment bolt, and the front and rear moving clearance should be noted down, and it should be evenly distributed between the front and rear guard plates of the impeller until the gap between the impeller and the front guard plate and the rear guard plate is equal. And tighten the two dust discs and fasten them on the shaft. After adjustment, it is necessary to re-check whether the impeller rotates normally and whether the bearing assembly hold-down bolt is tightened before starting again, and then start the pump.

3. Bearings need to be lubricated

When assembling the bearing assembly, if it is assembled correctly, the appropriate amount of lubricating oil, and the maintenance is timely, the transportation life will be longer. Therefore, maintenance personnel should regularly overhaul the bearing assembly, check the condition of the bearing and lubricating oil, add or replace the lubricating oil regularly during operation, and add lubricating oil in a reasonable and timely manner.

4. The standby pump should rotate the shaft 1 4 times a week to make the bearing evenly bear the static load and external vibration.