DL/T 1997-2019Cellular wet electrostatic precipitator (English PDF)

4.1 Product Classification

4.1.1 According to the layout, it can be divided into one-piece type and split type.

4.1.2 Integrated type refers to the arrangement in which the equipment is arranged on the upper part of the demister of the desulfurization absorption tower and integrated with the absorption tower.

4.1.3 Split type refers to the arrangement where the equipment is arranged outside the desulfurization absorption tower to form an independent device.

4.2 Structure composition

4.2.1 The wet electric dust collector (fog) is composed of mechanical equipment and electric control system.

4.2.2 Mechanical equipment includes shell, dust collector, discharge electrode, cleaning system, sewage system, hot air heating system and flow field distribution device.

4.2.3 The electrical control system includes electrical systems, control systems and measuring instruments.

5.2 Flue gas temperature (°C)

5.3 Flue gas pressure (Pa)

5.4 Smoke and dust concentration at inlet and outlet (mg/m3)

5.5 Inlet and outlet droplet concentration (mg/m3)

5.6 Flue gas velocity (m/s)

5.7 Specific dust collection area (m2/(m3/s))

5.8 Dust removal efficiency (%)

5.9 Mist removal efficiency (%)

5.10 Body resistance (Pa)

5.11 Air leakage rate (%)

5.12 Equipment availability (%)

5.13 Life of the whole machine (years)

6.1 General requirements

6.1.1 The layout method should be determined according to the site conditions, and the selection and design parameters refer to Appendix A.

6.1.2 The power supply area shall operate independently in different areas. 300MW units should be divided into 4 power supply areas, 600MW units should be divided into 4-6 power supply areas, the 1000MW unit should be divided into 6-8 power supply areas.

6.1.3 The dust collector is arranged vertically in a honeycomb structure, and the discharge electrode should adopt an integral suspended structure.

6.1.4 The equipment should be equipped with a cleaning system, a sewage system and a heating system.

6.1.5 The dust collector, discharge electrode and accessories should be made of corrosion-resistant materials according to the flue gas conditions.

6.1.6 Equipment manholes, valves, instruments and other frequently operated parts should be equipped with maintenance platforms, and the design of platform escalators should meet the requirements of GB 4053.

6.1.7 A lifting device should be provided on the top of the shell.

6.1.8 Manhole doors should be equipped with safety interlocking devices.

6.1.9 The equipment is equipped with a safe and reliable power supply and control system.

6.2 Main technical requirements

6.2.1 Shell

6.2.1.1 The design should comply with the relevant regulations of GB 50009 and GB 50017.

6.2.1.2 The structural parts shall adopt metal structure, and the material requirements shall not be lower than Q235.

6.2.1.3 Rectangular steel should be used for the dust collector suspension beam, and the supporting nodes should be simplified as much as possible to facilitate corrosion protection.

6.2.1.4 The manufacturing quality should meet the relevant requirements of DL/T 514.

6.2.1.5 There should be an inspection space between the inner wall and the dust collecting electrode.

6.2.1.6 The inner wall should be made of glass flakes for anti-corrosion, and the anti-corrosion should meet the requirements of HG/T 2640.The outer wall can be insulated according to the use environment temperature.

6.2.2 Dust collector

6.2.2.1 Non-metallic conductive materials or other corrosion-resistant alloy materials that are resistant to acid and chloride ion corrosion should be used.

6.2.3.2 The non-metallic conductive dust collector can be manufactured by pultrusion or hand lay-up, and the physical and chemical properties of the product should meet the requirements of DL/T 1844 related requirements.

6.2.2.3 The section should be a polygon with an inscribed circle diameter (Phi300mm~Phi400mm), the limit deviation of the inscribed circle is ±3 mm, non-metallic the thickness of one side of the dust collecting pole tube is >=3mm.

6.2.2.4 The effective length should be 4500mm~6000mm, and the length limit deviation should be ±10mm.

6.2.2.5 The integral structure shall be adopted, without splicing, the inner surface is smooth,, and without damaging scratches, and the inner surface flatness tolerance is 1mm;

Surface roughness Ra7 Test acceptance

7.1 No-load boost test

7.1.1 The insulation box and the holder must be tested for the hot air heating system, and the heating performance should meet the design requirements.

7.1.2 The high-voltage power supply must be subjected to insulation test, short circuit test (constant current source)/open circuit test (voltage source), which shall meet the design requirements.

7.1.3 The insulation resistance test should be carried out in the power supply load area, and the insulation resistance of each power supply area should be greater than.200Mohm.

7.1.4 The output voltage of the high-voltage power supply during no-load test shall not be less than 50kV, or the secondary current shall reach the rated value.

7.1.5 The cleaning system shall be subjected to manual/automatic tests, and the control shall meet the design requirements.

7.1.6 After meeting the requirements of (7.1.1~7.1.5), the no-load boost test shall be carried out after the water spray cleaning is completed, the voltage shall be increased step by step, and the record table the primary and secondary voltage and current values indicated by the panel.

7.1.7 When the no-load pressure rise test is carried out at altitudes higher than 1000m, atmospheric pressure correction shall be carried out. For every 100m increase in altitude, secondary voltage the value can be reduced by 1%.

7.2 Flow field uniformity test

7.2.1 The airflow uniformity coefficient at the entrance of the electric field shall be implemented in accordance with Table 3 and meet the requirements of DL/T 461.

7.2.2 The uniform distribution of the flow field can be verified by numerical simulation calculation or physical model test.

7.2.3 The simulation calculation range of the split structure should include the exhaust flue range of the desulfurization absorption tower; the simulation calculation range of the integrated structure should include the desulfurization Range of flue at the entrance of absorption tower.

7.2.4 Solve the problem of inlet flow deviation by optimizing and adjusting the flow field. The relative flow deviation of the inlet of each chamber of the electric field should be less than 10%.

7.3 Performance test

7.3.1 Test content

7.3.1.1 Smoke emission concentration

7.3.1.2 Dust removal efficiency

7.3.1.3 Resistance

7.3.1.4 Air leakage rate

7.3.1.5 Running power consumption

7.3.1.6 Running water consumption

7.3.1.7 Noise

7.3.1.8 PM2.5, PM10, fog drop, SO3, etc. can be tested according to project requirements

7.3.2 Layout of measuring points

7.3.2.1 The arrangement of measuring points shall meet the relevant requirements of GB/T 16157.

7.3.2.2 The flow field uniformity coefficient of the test section shall be less than 0.25.

7.3.2.3 The test location shall have stairs and platforms.

7.3.2.4 The inner diameter of the sampling hole should not be less than 90mm, and the sampling hole with an inner diameter of 90mm~120mm should be selected.

7.3.3 Test equipment

7.3.3.1 The test instrument shall meet the relevant requirements of GB/T 16157 and HJ/T 48 and have the function of air tightness inspection.

7.3.3.2 The sampling device shall be made of corrosion-resistant materials, and shall have a heating function. The heating temperature shall be adjustable from 60°C to 120°C.

7.3.3.3 The smoke and dust test shall adopt the combined sampling head integral weighing method.

7.3.3.4 The filter membrane should be made of quartz or polytetrafluoroethylene.

7.3.4 Test method

7.3.4.1 The smoke and dust test method shall meet the relevant requirements of HJ836, GB/T 16157 and GB/T 13931.

7.3.4.2 The effective sampling number of the smoke and dust test shall not be less than 5 groups.

7.3.4.3 The fog drop and SO3 test meet the relevant requirements of GB/T 21508.

7.3.4.4 PM2.5 and PM10 tests shall meet the relevant requirements of DL/T 1520 and GB/T 16157.

7.3.4.5 The analysis of smoke and dust samples shall meet the relevant requirements of HJ836, GB/T 16157, and GB/T 13931.

8.1 Factory inspection

The factory inspection is carried out in accordance with the requirements of the relevant standards of each equipment.

8.2 Transportation inspection

The transportation inspection is jointly responsible by the installation unit and the manufacturing unit, and the inspection shall be carried out according to the construction drawing and the shipping list.

9.1 Nameplate mark

The type and size of the product nameplate should meet the requirements of GB/T 13306, and be fixed in a prominent position of the equipment, mainly including the following.

a) Product name

b) Performance parameters. processed flue gas volume, specific dust collection area, power supply area, power supply specifications, smoke emission concentration

c) Factory number

d) Name of manufacturer

e) Production date

9.2 Packaging mark

9.2.1 The packaging signs should include the receipt and delivery signs, and the packaging, storage and transportation pictorial signs, and should comply with GB/T 191 and GB/T 6388.

9.2.2 The packaging of electronic control equipment, dust collector, cathode frame, insulating porcelain bottle, etc. should be marked with the words "fireproof, moisture-proof, pressure-proof, and handle with care".