Complaint
High-efficiency continuous exhaust waste heat recovery device
Utility model patent: ∶zL 20142043463.4
One.summary
Industrial boilers and power station boilers with a capacity of more than six tons are equipped with continuous blowdown systems. Usually, the discharge rate of industrial boilers is between 79% and 10%, and that of utility boilers is between 1% and 3%. The discharged sewage is saturated and contains a lot of heat energy. For example, the temperature of the discharged sewage of a medium-temperature and medium-pressure boiler (4Mpa) is 250ºC and its enthalpy is as high as 259.7Kg.
The common continuous flash tank can recover part of heat energy and working medium by flash evaporation, but the continuous flash tank can't cool the sewage below 100ºC (usually 105-10ºC), so the recovered heat is very limited.
Some even directly discharge the flash steam into the atmosphere, and the energy loss is serious. Moreover, the continuous expansion vessel is tall and bulky, Complex system with high failure rate. The new high-efficiency waste heat recovery device produced by our company directly recovers the heat of continuous sewage discharge through heat exchange.
For industrial casting furnaces, make-up water can be used to cool the sewage; for power station boilers, in addition to make-up water, turbine condensate can also be used to cool the sewage.
Two.Product structure and working principle
According to the specific situation of the power plant, our company has two sets of design schemes.
Scheme 2: The boiler continuously discharges sewage to drain water and directly enters the waste heat recovery device. Because the cooling water temperature is normal temperature or slightly higher than normal temperature, the sewage can be cooled to a lower temperature. Recover most (70%-90%) of the heat loss from sewage discharge. Because of the novel heat exchange method, the product has the advantages of large heat exchange coefficient, compact structure, regular shape, convenient installation, reliable operation, good water quality after recycling, and being able to replace continuous expansion vessels.
Three.Model description .
Model example: JSLG-40, which means the continuous exhaust waste heat recovery device with 40 boiler evaporation capacity produced by Lianyungang Jiusheng Company.
Four.Installation and Connection
1.Installation
This product is light in weight, so it is generally unnecessary to consider the bearing capacity of the ground when it is installed on the zero-meter floor. When installed in the boiler operation layer or oxygen removal layer, the place with strong bearing capacity should be selected, and the bearing capacity of the ground should be checked when necessary. The center of gravity of this product is low, so it can be installed by matching the corresponding fixing bolts according to the bottom anchor holes.
V.Debugging, operation and withdrawl
After the waste heat recovery device is installed and connected with the system, it can be debugged.
1. Open the cooling water bypass valve and check whether the cooling water is unblocked.
2. Open the cooling water inlet valve and check the tightness of the cooling water side.
3. Open the cooling water outlet valve, slowly close the cooling water bypass valve, and check whether the cooling water is smooth.
4. Slowly open the sewage inlet valve (if multiple boilers share one waste heat recovery device with fixed discharge, it can be opened in turn), and check whether there is any leakage, abnormal noise or vibration at the welding joint.
5. Slowly open the sewage outlet valve and gradually adjust to the required flow rate.
6. Note that you must first open (fully open) the sewage inlet valve, and adjust the sewage flow rate with the outlet valve. Otherwise, the sewage may be vaporized due to sudden pressure drop, causing equipment vibration and even water attack.
7. When the waste heat recovery unit is handed over because of maintenance and inspection, it should first close the sewage outlet valve, then close the sewage inlet valve, open the cooling water bypass valve, and then close the cooling water inlet and outlet valve.
Six.ordering instructions
Users should provide the following data when ordering:
1.Order quantity
2. Connection mode (single connection or common connection)
3. Boiler capacity and related parameters
4.Technical parameters of continuous expansion vessel
Specification Cmm of drain pipe Working pressure: Mpa working temperatureºC Volume m Exhaust Pipe Diameter mm
Specification sheet for waste heat recovery unit tube exchange.
| No. | Tube O.D. (mm) | Wall thickness (mm) | Range of distances (mm) |
| 1 | φ12 | 1.0~2.0 | 40~500 |
| 2 | φ14 | 1.0~2.0 | 40~500 |
| 3 | φ16 | 0.9~2.5 | 60~718 |
| 4 | φ19 | 1.0~2.5 | 70~480 |
| 5 | φ20 | 1.0~2.5 | 80~470 |
| 6 | φ22 | 1.2~2.5 | 80~526 |
| 7 | φ25 | 1.5~2.5 | 80~634 |
| 8 | φ27 | 1.5~2.5 | 100~400 |
| 9 | φ32 | 2.0~3.0 | 150~320 |
Common faults and treatment
1.The waste heat recovery device vibrates or has water attack.
A.Check whether there is blockage or insufficient opening of the primary valve and sewage inlet valve of the boiler, and if so, eliminate it.
B. Check whether the opening of the sewage outlet valve is too large, and whether the sewage flow rate is too large. If so, try to turn down the sewage outlet valve to reduce the discharge amount.
C. Check whether the cooling water is unobstructed, whether the cooling water bypass valve is opened by mistake, and whether the cooling water quantity is enough. If the cooling water quantity is insufficient, open the cooling water inlet and outlet valve and close the mistakenly opened bypass valve.
2. The amount of sewage is insufficient. Check whether the flow restrictor is plugged or not, if so, remove it and clean it.
3. Packing leakage at cooling water side. Open the packing side shell and properly press the gland nut. When the high-efficiency waste heat recovery device runs for too long (more than 10 years), part or all of the packing can be replaced.
4. Leakage on the high voltage side. The sewage heat exchange side of this product (that is, part of the high-pressure pipe inside the outer pipe) is made of seamless thick-walled pipe, and there is no welded joint in the middle, so it can be used normally, and generally no leakage will occur. If it is found that the conductivity of boiler feedwater increases, open the front and back sampling needle valves to test the conductivity.
