1.DZL series water and fire tube boiler use a lot of new technologies, for example, thread smoke tube, wing flue, arch-tube plate,self fixture, return water injection, etc. They can not only eliminate the disadvantages of drum deformation,tube sheet crack, water cooling wall burst but also can save energy and be more efficient.
2.Smoke circulation: The hot smoke burst from grate erupts from middle of arch —- rear furnace—-wing flue—-front smoke chamber—-thread smoke tube—-rear smoke chamber—-flue—-economizer—-dust collector—-induced draft fan—-chimney.
3.Air flows: forced draft fan—-underground wind duct—-air chamber at two sides of grate—-separated wind chamber under grate-supply air for the burning by ventilation holes
opening at the grate.
Cool down smoke in high temperature tube sheet, avoid subcooled boiling, reduce boiler bottom heat load, avoid tube sheet crack, avoid drum deformation.
2.Arch tube plate
Improve tube sheet flexibility, reduce welding seam thermal stress. Cancel brace and avoid tube sheet crack.
3.Thread gas tube
Enhance heat transfer,reduce drum size,improve flexibility,reduce welding seam thermal stress.
No dust accumulation, avoid tube and sheet crack.
1.The boiler is small and compact. Thread smoke tubes replaces smooth tubes, then the tubes heat transfer efficiency is 1.7-1.8 higher than previous, which decreases boiler required heating surface and boiler volume. This makes the boiler easier to transport, layout, install and reduces engineering cost.
2.The boiler mainly adopts thread smoke tubes as convection heating surface. The tubes is laid inside the boiler drum. Then the boiler has a compact structure and prevents cool air permeating into smoke side. Less air leakage lows exhaust smoke loss and improve boiler efficiency.
3.Arch tube plate and one-pass thread smoke tube inside the drum effectively avoids tube sheet crack during operation.
4.Wing flue covers drum bottom effectively avoids drum bottom deformation during operation.
Soot inertial separation device is set inside boiler and Big volume natural sedimentation chamber is set on the rear arch top. Smoke flow speeds is slow here, some particles in the smoke can be separated out because of gravity. The smoke turns fast at the head of wing flue, and many particles are separated out because of inertia. It lows original emission concentration. The ash in the rear arch can fall on the grate by ash falling hole, then be removed, which decreases secondary pollution. The boiler operates well and turns out that the original emission concentration is less than 2000mg/Nm³. Besides, with the equipped high efficiency dust collector, the boiler emission concentration satisfies national 1-class standard.
The intense radiation furnace arch can form reasonable A style fire to prompt the combustion. Water cooling wall forms furnace upon the grate. It is big enough to burn the coal completely. The reasonable arch arrangement ensures flow speed. Meanwhile, the inside thread smoke tube, high efficient burning device, well-designed arches and high quality insulation materials and other characteristics ensure the boiler thermal efficiency is higher than national standard.
All the circulation are independent and simple, which greatly avoid water cooling wall crack.
1.In design perspective, we design bigger contribution allowance. Our verifying calculation turns out that the contribution allowance is more than 10%. The boiler operation practice indicates that the use of high efficient heat transfer component—-thread smoke tube with enough screw thread makes the boiler output 10% high than nameplate rated capacity.
2.The equipment operates stably. The reasonable smoke speed enable no ash deposition on the thread smoke tube in the operation. So the boiler output and thermal efficiency wont decrease along with the long operation time. As a result, the boiler can keep ideal sustainable output and efficient.
The sufficient heating surface enables the fuel heat be absorbed amply. Calculation shows that smoke exhaust temperature is at 160ºC. On the other hand, we arrange furnace arch and furnace wall reasonably. The furnace wall is tight while the expansion seam is rational, which decrease cool air leak into boiler. The boiler thermal efficiency is up to 80%.
Flexible load regulation
Big water volume, high heat storage capacity, nearly 1/3 drum heating surface with many high efficiency thread smoke tube inside the boiler drum apparently reduce boiler heating time.
|(t/h) Rated evaporation capacity||4||6||8||10||15||20||25||30|
|(Mpa) Rated working pressure||1.6||1.6||1.6||1.6||1.6||1.6||1.6||1.6|
|(ºC) Rated steam temperature||204||204||204||204||204||204||204||204|
|(ºC) Feed water temperature||20||150|
|() Radiation heating area||12.24||19.2||22.1||24.15||34.5||53.7||99.2|
|() Convection heat area||89.55||115.3||128||168.2||339.9||411.8||457.8||628.6|
|() Economizer heat area||28.16||52.3||52.8||130.8||150.4||188||295||413|
|() Grate effective area||5.18||7.7||9.07||11.53||16.24||22.84||24.7||26.88|
|Suitable coal type||AII|
|(kg/h) Coal consumption||615||870||1153||1440||2165||2868||3550||4254|
|(%) design thermal efficiency||78.45||77.26||80.63||79.7||80.5||81.1||81.2||81.5|
|Max transport (××)(m)||7.06×2.96×3.60||7.60×2.95×3.70||7.34×3.00×3.70||7.20×3.50×3.70 7.50×2.30×2.60||7.33×3.37×3.70 8.90×3.37×2.50||7.81×3.37×3.51 9.44×3.77×2.60||8.47×2.60×2.74 12.00×8.02×8.90||9.00×2.60×2.85 12.00×8.20×9.70|
|(t) Max transport weight||30||42||46||25/18.5||27/25||29/28.5||31/33||35/36|
|Feed water pump||type||1 1/2GC-5×9||2GC-5×7||2GC-5×7||2 1/2-6×8||DG25-30×8||DG25-30×8|
|(kw)electrical power||1.1||1.5||1.5||1.5||2.2 ()||2.2 ()|