Easily serviceable single-drum DZH coal fired steam boiler for
parboiling rice mill
Description
The coal-fired boiler developed by our company uses negative
pressure and gasification technology to make the soot fully mixed
with oxygen at high temperature. A secondary combustion chamber is
arranged inside the furnace, and the unburned soot (gas) and the
coal slag can be burned for the second time, thereby achieving the
effect of energy saving. At the same time, the equipment adopts
three-pass water-fire tube heat exchange technology, which reduces
the flue gas discharge temperature (less than 110 degrees). The
boiler operates at normal pressure and adopts an automatic
temperature control system to facilitate temperature adjustment.
The product has high performance, beautiful appearance and compact
structure. The coal-fired boiler is composed of a pulverized coal
preparation system, a burner, a heating surface, and an air
preheater.
Features
1. The application of advanced technology can quickly form a high
temperature zone inside the boiler, stably maintain the combustion
state of the fuel, ensure that the flue gas can stay in the high
temperature furnace for a long time, the fuel is fully burned, and
the combustion efficiency is high.
2. The emission concentrations of soot and sulfur dioxide are not
more than 10mg/m3 and 50mg/m3 respectively, which reduces air
pollution.
3. The application of automatic feeding and slag removal equipment
can fully automate the boiler work. At the same time, the boiler
can work continuously for 4,000 hours without maintenance, and the
work is stable and reliable.
4. Take effective measures to prevent high temperature corrosion
and low temperature corrosion. The company has taken a lot of
measures to prevent corrosion during boiler design. At the same
time, the heated surface adopts high-grade corrosion-resistant
materials. For example, high-temperature three-stage and four-stage
superheater materials are all made of stainless steel SA-213TP347H,
and air preheater materials are used. JNS is resistant to sulfuric
acid dew point corrosion steel (having resistance to sulfuric acid
and hydrochloric acid).
5. Adopt international leading dust collector technology. The dust
collector technology developed by the company has the
characteristics of high ash removal efficiency, compact structure,
small floor space and flexible layout. After the dust is removed
from the dust, the discharge fully meets the environmental
requirements.
6. The boiler body is automatically welded by argon arc welding
process, 100% non-destructive testing, excellent quality.
| Parameters Table for DZH 0.5-6 ton |
| Item No. | DZH0.5-0.7 | DZH1-1.0 | DZH1-1.25 | DZH2-1.0 | DZH2-1.25 | DZH4-1.25 | DZH4-1.6 | DZH6-1.25 |
| Rated steam output(t/h) | 0.5 | 1 | 1 | 2 | 2 | 4 | 4 | 6 |
| Rated work pressure(Mpa) | 0.7 | 1 | 1.25 | 1 | 1.25 | 1.25 | 1.6 | 1.25 |
| Rated steam temperature(°C) | 165.3 | 184 | 194 | 184 | 194 | 194 | 204 | 194 |
| Rated feed water temperature(°C) | 20 | 20 | 20 | 20 | 20 | 20 | 20 | 20 |
| Thermal efficiency(%) | 76.6 | 77.18 | 77.6 | 76.8 | 77.7 | 78.8 | 78.8 | 78.5 |
| Fuel consumption (kg/h) | 79 | 172 | 178 | 358 | 361 | 726 | 732 | 1080 |
| Shipping size(m) | 3.67*
1.76*
2.78 | 4.31*
1.9*
2.86 | 4.31
*1.9*
2.85 | 5.41
*2.6*
3.1 | 5.41
*2.6*
3.26 | 5.86
*2.8*
3.39 | 5.86
*2.8*
3.4 | 6.2*
2.96*
3.58 |
Structure classification of pulverized coal burner
The pulverized coal burner is a device that feeds pulverized coal
into the furnace for combustion, and can be classified into a
cyclone burner and a direct-flow burner. The following is a
detailed description of the two burners.
1. Swirling burner. The primary air carrying pulverized coal and
the secondary air without pulverized coal are connected to the
burner by different pipes. The pulverized coal and air can be
thoroughly mixed and form a re-circulation zone. Each boiler can be
configured with 4 to 48 burners.
2. DC burner: The nozzle is narrow, and the primary and secondary
air do not rotate in the burner. The pulverized coal can be
completely burned therein.
The heated surface separates the heated surface from the heated
surface and the heated surface. Modern large and medium-sized
boilers are constructed of water-cooled walls, whereby the
water-cooled wall (the heated surface) absorbs the radiant heat in
the furnace to evaporate the water into saturated steam. In order
to increase the radiant heating surface without increasing the
volume of the furnace, the large boiler can be double-exposed
water-cooled wall. The superheated heating surface can be divided
into a screen type superheater heating surface arranged on the
upper part of the furnace and a convection superheater heating
surface arranged in the convection flue. The former absorbs radiant
heat in the furnace; the latter absorbs convective heat.
Fault diagnosis and processing system features
The system can monitor the current working conditions of the gas
steam boiler in real time, and carry out real-time and
comprehensive intelligent fault identification and processing. The
control system is capable of diagnosing and processing the
following faults in real time.
1). Steam pressure over-limit protection: When the steam in the pot
is over-pressure, the control system immediately enters the
equipment to stop working, and the sound and light alarm is given.
The screen displays “Vapor pressure is extremely high”. Until the
fault is eliminated, press the reset button to cancel the alarm
state.
2). Water shortage protection: When the boiler has a low water
level failure due to pump failure or other reasons, the control
system immediately turns off the burner power supply, enters the
interlocking state, sound and light alarm until the fault is
eliminated, and then press the reset button to cancel the alarm
state.
3). Boiler water level over-limit protection: When the water level
is higher than the upper limit warning water level, the sound and
light alarm. Prompt "the water level in the pot is too high", the
display prompts drainage, and the pump starts to drain. The fault
is automatically restored after the fault is eliminated, and the
pump stops working.
Data table 1
| Auxiliary components |
| Auxiliary System | Parts |
| Water supply system | soft water, demineralized water system, deaerator, feed water pump,
water tank, ammonia adding device, dosing device |
| Steam (hot water) system | Steam separator (water) cylinder, desuperheater |
| Fuel supply system | Coal machine, belt coal conveyor, crusher, vibrating screen
electronic belt scale, electromagnetic iron remover, double pear
type unloader, pre-furnace coal feeder, etc |
| Smoke system | Blower, induced draft fan, chimney, etc.
Sewage (steam) system, row, row, sampler, silencer |
| Electronic control system | General control, PLC control, DCS control |
| Other equipment in the boiler room | Heat exchange station, circulation pump, decontamination unit, etc. |
| Flue gas purification system | Dust collector, desulfurization device, denitration device, etc. |
| Quckly installed boiler |
| boiler model | Unit | DZL1-0.7/1.0-AII | DZL2-0.7/1.0-AII | DZL4-0.7/1.25/1.6-AII | DZL6-1.25/1.6-AII |
| capacity | ton/h | 1 | 2 | 4 | 6 |
| rated pressure | Mpa | 0.7/1.0 | 0.7/1.0 | 0.7/1.25/1.6 | 1.25/1.6 |
| rated steam temeperature | ℃ | 170/184 | 170/184 | 184/193/204 | 193/204 |
| feed water temperature | ℃ | 20 | 20 | 20 | 105 |
| radiation area | ㎡ | 4.21 | 6.43 | 10.55 | 16.95 |
| convection area | ㎡ | 20.68 | 39.23 | 90.45 | 134.87 |
| economizer area | ㎡ | 9.66 | 16.56 | 16.56 | 53.13 |
| valid grate area | ㎡ | 1.852 | 3.15 | 5.18 | 8.395 |
| applicable fuel | * | COAL | COAL | COAL | COAL |
| exhaust gas temperature | ℃ | 152/160 | 152/161 | 163/163.8/169.5 | 163/169 |
| design efficiency | % | 77.73/77.24 | 78.53/78.18 | 79.37/79.30/78.96 | 79.83/79.19 |
| fuel consumption | kg/h | 170.74/172.93 | 341.71/343.63 | 673.22/676.27/682.11 | 866.39/877.51 |
| max part size for delivery | mm | 5488*2254*2782 | 5694*2704*3324 | 6743*2954*3508 | 8244*2951*3704 |
