Application of sewage water source heat pump?

The application of sewage source heat pump is very important. Knowing the function and precautions of sewage source heat pump can play a better role, and it is very important to deal with every detail. Zhong Da Consulting will introduce the application of sewage source heat pump to you.

1, preface

Water-source heat pump technology is a low-temperature and low-level heat energy resource, which uses solar energy and geothermal energy absorbed by shallow water sources such as groundwater, rivers and lakes, and adopts the heat pump principle to realize the conversion from low-level heat energy to high-level heat energy through a small amount of high-level electric energy input [1 2]. Generally, COP (the ratio of heating capacity to input power that a heat pump system can achieve) is used as its energy-saving evaluation index.

Effluent from sewage plant is an excellent low-temperature residual heat source. During the whole heating period (cooling period), the fluctuation of water temperature is small, the water resources are concentrated and the water quality is good. It is an ideal low temperature heat source for water source heat pump. Vigorously developing water source heat pump air conditioning system with secondary effluent from urban sewage treatment plant as water source can not only solve the problems of personnel heating and equipment insulation, but also bring huge economic and environmental benefits to enterprises and society.

2. Working principle of water source heat pump

Water source heat pump is based on the relatively stable temperature of groundwater (surface water) at room temperature, which can be divided into two operation modes: winter and summer. In winter: when the unit is in heating mode, it absorbs heat from groundwater (surface water), concentrates the heat of groundwater (surface water) through electrically driven compressor and heat exchanger, and releases it indoors at a higher temperature. Summer: when the unit is in refrigeration mode, the cooling capacity is extracted from groundwater (surface water), and the cooling capacity is sent indoors through the operation of the unit, and the indoor heat is discharged into groundwater (surface water) to achieve the purpose of air conditioning.

2. 1 system composition

The water source central air conditioning system consists of terminal system, water source central air conditioning host system and water source system. When heating users, the water source central air-conditioning system extracts low-grade heat energy from the water source and delivers it to the high-temperature heat source through the "pump" of the water source central air-conditioning host driven by electric energy to meet the heating needs of users. When the water source central air conditioner provides refrigeration for users, it transfers the indoor residual heat of users to the water source through the main engine of the water source central air conditioner to meet the cooling needs of users.

2.2 Water source application conditions

1. The water temperature of source water shall be 12-22℃ during heating operation and 18-30℃ during cooling operation.

2. The pH value of source water should be 6.5 ~ 9.0.

3. The content of calcium oxide in source water is less than 200mg/L. 。

4. Salinity of source water

5. When using water source heat pump system, corrosion-resistant stainless steel heat exchanger or titanium plate heat exchanger should be installed in the system.

6. The design of water intake should consider the water temperature factor, the guarantee rate of water intake and the relationship between the elevation of water intake structure and the water level in flood season.

3. Feasibility analysis of sewage as water source

3. 1 The sewage source flow is large and stable.

As can be seen from the table, the treatment capacity of existing sewage plants is 0.2-30,000 m3/d, and the heating area that can be met is 0.8-10.2 million m2, while the heating (refrigeration) area of each water plant is approximately 0.5-0.5 million m2, so the existing sewage treatment capacity can fully meet the demand.

3.2 Sewage is warm in winter and cool in summer

In winter, even in severe cold areas, the temperature of sewage is above 10- 18℃, which is a rich heat source. In summer, the temperature of sewage is 20-28℃, which is an ideal place to discharge waste heat.

3.3 Sewage quality

The effluent of the existing sewage treatment plants is required to meet the Grade A standard in the Discharge Standard of Pollutants for Urban Sewage Treatment Plants (GB 189 18-2002).

The suspended matter in the water quality standard is 10mg/L, and the pH value is 6-9, which meets the technical requirements of water source heat pump. At the same time, the existing water source heat pump systems all have their own suspended matter filtering and anti-corrosion equipment to avoid affecting the heating equipment.

3.4 sewage heat energy utilization field is wide.

Because the current heat pump technology has developed to the stage of directly recovering the heat energy of untreated urban sewage, it has expanded the use area in the city.

According to the investigation line, the main manufacturers of water source heat pump are: Tsinghua Tongfang Artificial Environment, Beijing Senotel, etc.

3.5 Limitations of other renewable energy sources

The development of underground water source heat pump system in China is limited because 1) China lacks water resources; 2) Well water recharge technology of underground water source heat pump system is not mature at present; 3) In addition, there are problems such as exhaustion and aging of water wells.

In the ground source heat pump system, due to the low efficiency of soil heat exchange; 2) The initial investment of the system is high, and the fault caused by operation is not easy to repair.

Therefore, it has great advantages to use sewage instead of groundwater and soil as heat source.

4. Scientific analysis of sewage as water source

Sewage source heat pump technology can consume about 25% electric energy to extract more than 75% sewage heat energy, and get 100% heating heat energy. If the thermal power generation efficiency is 0.33, the primary energy utilization rate of the system is as high as 1.33, and even the most efficient boiler efficiency is below 0.9. Considering the auxiliary energy consumption and heat loss, the primary energy of sewage heat pump air conditioning system can save more than 45%.

5. Economic analysis of sewage as water source

The service life of water source heat pump is about 20 years, and the power consumption is1kw h. Users can get 4.3-5.0 kW·h of heat or 5.4-6.2 kW·h of cold energy.

Taking a sewage treatment plant in Qingdao (heating area: 80* 104m2, air conditioning area: 50* 104m2) as an example, the economic benefits and energy saving of water source heat pump system and natural gas direct-fired heat pump unit are compared respectively. The results show that the total cost of direct sewage source heat pump system is 88.5% of that of gas turbine, the operating cost is 765,438+0.2% of that of gas turbine, and the annual cost is 75.8% of that of gas turbine. It embodies the economy of direct sewage source heat pump.

6. Environmental benefit analysis of sewage as water source

6. 1 The power consumption of water source heat pump unit is equivalent to reducing greenhouse gas emissions by more than 70% compared with electric heating.

6.2 When using water source heat pump for heating, it can replace the boiler room system, and there is no combustion process, thus avoiding the smoke pollution. When cooling, the cooling tower is omitted, avoiding the noise and mold pollution of the cooling tower, making the environment cleaner and more beautiful.

7. Conclusion

1, water source heat pump has the characteristics of high efficiency, energy saving, environmental protection, convenience and comfort.

2. The pretreatment device should be added to the water source heat pump to make the inlet water meet the use requirements.

3. The power consumption of water source heat pump is1kW h, and users can get 4.3-5.0 kW·h of heat or 5.4-6.2 kW·h of cold energy.

4. Water source heat pump is a kind of clean energy, and it will not produce secondary pollution during use. In areas with strict requirements for boiler combustion, the use of water source heat pump has good economic, environmental and social benefits.

Want to know more about "sewage water source heat pump application" in detail, the construction design of Zhong Da Consulting is simple, convenient and reliable.

For more information about project/service/procurement bidding, and to improve the winning rate, please click on the bottom of official website Customer Service for free consultation:/#/? source=bdzd