Content |
refrigeration unit |
Heating unit |
Cold heat |
930kw |
1860kw |
energy consumption |
185kw |
2.65m³steam |
Hot and cold water temperature |
12/7℃ |
75/55℃ |
Drying room temperature |
4 air chamber 40 ℃, relative humidity 55%, 8 air chamber 55 ℃, 18% |
2: Heat recoverable from the production line
Num
Cooling equipment
Enthalpy of temperature and humidity
at state point
Airflow
Heat recovery
1
4 air chamber exhaust
40℃,55%,108kj/kg
15000m³/h
164kw
2
8 exhaust of air chamber
55℃,18%,102kj/kg
10000m³/h
111kw
3
Regeneration exhaust
40,55%,108kj/kg
20000m³/h
250kw
4
Return air of air cabinet
40,40%,108kj/kg
45000m³/h
515kw
Total:
1040kw
Project design
1.Description of heating system transformation
The project is designed by H.Stars Group and adopted with two high-temperature water source heat pump units, which are connected in series to the heating return water of the original system to the steam heating section. The heating return water of the original system is first heated by adding the primary and secondary heating of the high-temperature water source heat pump unit. If the outlet water temperature of the heat pump does not reach the set 75 ℃ after heating, the steam heating will start automatically. The heating capacity of the primary high temperature water source heat pump unit is 818kw and the input power is 235Kw; The heating capacity of two-stage high temperature water source heat pump unit is 806kw and the input power is 265KW.
2. Description of exhaust heat recovery transformation :
A 10³m is added in the design The square insulated water tank transmits 15 ℃ cold water to each heat recovery ceiling air cabinet through the circulating pump, and the 20 ℃ hot water heated by exhaust air returns to the insulated water tank for heating by high-temperature heat pump unit; Reduce the enthalpy of exhaust air and reduce the surrounding thermal pollution.
3. Description of return air heat recovery Transformation:
The return air contains a large amount of water vapor and high enthalpy. A ceiling heat recovery air cabinet is installed on the return air duct to reduce the water vapor content and enthalpy of the return air, reduce the energy consumption of lithium chloride dehumidifier, and the recovered heat is supplied to the high-temperature heat pump unit.
4. Recycling instructions of heat pump chilled water in summer :
The system was originally equipped with a 930kw refrigerating capacity refrigeration unit to cool and dehumidify the fresh air in summer and the lithium chloride dehumidifier. The water supply temperature is 12 / 7 ℃, while the heat pump unit can adjust the water temperature at the cold source side to 12 / 7 ℃ when working in summer. The supply and return water at the cold source side can directly replace the supply and return water of the original refrigeration unit and reduce the operation energy consumption of the original system.
Project system diagram
Program advantages
1. The high-temperature water source heat pump unit is used for both cooling and heating. The energy efficiency ratio of the unit is more than 3.0 and the comprehensive energy efficiency ratio is as high as 7.0. The operation energy consumption is low, saving more than 50% of the operation cost compared with the original system .
2. Reclaiming the heat from the exhaust of the original system for heating can kill two birds with one stone. First, the heat pump unit has high efficiency and low operation energy consumption; Second, reduce the heat and water vapor of exhaust air, reduce emissions and improve the surrounding environment .
3. Recover the heat and water vapor of the return air of the original system, that is, reduce the water vapor and enthalpy of the return air, reduce the energy consumption of re dehumidification of the return air and reduce the operation cost .
4. When working in summer, the supply and return water temperature at the cold source side of the high-temperature heat pump unit can also be adjusted to replace the original refrigeration unit, reduce the service time of the original refrigeration unit and reduce the system operation cost
5. The whole system adopts full-automatic control and is automatically put into operation according to temperature changes to reduce energy consumption.
6. The project is equipped with a central computer room with integrated design and centralized management to minimize investment cost and operation management cost.
Economic analysis of project operation before and after transformation
Num |
Project |
Refrigeration and steam heating of refrigeration unit |
High temperature water source heat pump unit for cooling and heating |
||||||
model |
unit |
Cooling capacity(Kw) |
power(KW) |
model |
unit |
Cooling capacity(Kw) |
power(KW) |
||
1 |
Water chiller |
|
1 |
930 |
185 |
New heat pump unit |
2 |
1126 |
500 |
2 |
Steam heating capacity |
Party A's original |
1 |
1860 |
2.65 |
Heating capacity of heat pump unit |
1 |
1626 |
0 |
3 |
Cooling water pump |
Party A's original |
1 |
|
37 |
Fan power of air cabinet |
1 |
|
10 |
4 |
Cooling tower |
HD-250 |
1 |
|
7.5 |
|
|
|
|
5 |
Total cooling power |
229.5 |
0 |
||||||
6 |
Total heating power |
2.65T steam |
510kw |
||||||
7 |
Cooling operation mode |
Cooling tower+water chiller |
Cold recovery of heat pump unit |
||||||
8 |
Annual operation days (D) |
90 |
90 |
||||||
9 |
Daily running time(H) |
24 |
24 |
||||||
10 |
Annual operation time(H) |
2,160 |
2,160 |
||||||
11 |
Annual average operating load rate(%) |
0.80 |
0.80 |
||||||
12 |
Annual cooling power consumption(KWH) |
396,576 |
0 |
||||||
13 |
Customer electricity billing is 0.6yuan/KWH |
237,946 |
0 |
||||||
14 |
Cost saving of cooling |
237,946 |
|||||||
15 |
Heating operation mode |
steam |
Heat pump unit |
||||||
16 |
Annual operation days (D) |
360 |
360 |
||||||
17 |
Daily running time(H |
24 |
24 |
||||||
18 |
Annual operation time(H |
8,640 |
8,640 |
||||||
19 |
Annual average operating load rate(%) |
0.80 |
0.80 |
||||||
20 |
Annual power consumption of heat pump unit in machine room(KWH) |
18,317 |
3,525,120 |
||||||
21 |
Customer electricity billing is 0.35/KWH,steam 200yuan/t |
3,663,360 |
1,339,546 |
||||||
22 |
Saving cost of heating |
2,323,814 |
|||||||
23 |
Total annual savings |
2,474,513 |
|||||||
24 |
Energy saving rate |
68% |