Application of new screw heat recovery chiller
1 Introduction with the increasing development of economy and the continuous improvement of human living standards, the application of air conditioning is becoming more and more popular. While air conditioning adapts to economic development and meets human needs, it also brings a huge burden of energy consumption and other negative effects such as the greenhouse effect. Therefore, reducing the energy consumption of air conditioning and seeking the way of sustainable development of air conditioning have become an important and primary problem faced by air conditioning design. Before discussing the content of this paper, it is necessary to classify the energy consumption of air conditioning, and make some classification and comparison of the existing energy-saving technologies of air conditioning
2. Classification of air conditioning energy consumption: electric power or steam should be used for air conditioning refrigeration; The transmission of water and gas for air conditioning consumes electricity; In winter, air conditioning should use electricity, oil, coal and other natural energy. Different seasons and different air conditioning systems have different energy consumption. But in terms of classification, it can be divided into two categories: power consumption and heat consumption. However, electricity consumption can still be attributed to heat energy consumption (except natural energy power generation). Therefore, from the perspective of environmental protection, all energy consumption of air conditioning is heat energy consumption, with the emission cost of CO2 and greenhouse gases. Specifically, in the air conditioning system, all electric drive equipment has power consumption; All kinds of boilers and lithium bromide chillers have heat energy consumption. In the case of a Rotating Zigzag rod, air conditioners in summer, except lithium bromide chillers, are dominated by power consumption; In winter, air conditioning is dominated by heat energy consumption, but there is also power consumption. Air conditioning systems of various air sources, water sources and ground sources only consume electricity. 3. Classification and comparison of air-conditioning energy-saving technology as a reward for continuous exploration of air-conditioning energy-saving technology, there are many mature technologies and related products available in air-conditioning design. Specifically, it can be divided into three types: 3.1 saving type: by pursuing high efficiency, optimizing the system and strengthening the application of automatic control, we can save energy consumption in air conditioning operation, reduce or avoid energy waste, so as to save energy. For example, select high-efficiency products, optimize system configuration, adopt energy-saving systems such as variable air volume or variable water volume, secondary return air, and other operation control energy-saving technologies. In terms of the energy consumption saved, it saves not only the power consumption of air conditioning, but also some heat energy consumption of air conditioning. 3.2 natural energy utilization type: reduce the energy consumption of air conditioning by using natural energy reasonably, such as natural energy utilization technologies such as fresh air cooling, cooling water cooling, air source, water source and ground source cooling and heating. The natural energy utilization type mainly saves the heat energy consumption of air conditioning. It is worth noting that the heat energy saved is considerable. In addition, the energy consumption of air conditioning is saved, and the corresponding CO2 emission is reduced to within ± 0.5% of the set value;, Therefore, it has good environmental protection advantages and sustainable development characteristics. 3.3 heat recovery type: through the recycling of heat energy, realize the secondary utilization of heat energy, so as to reduce the energy consumption of air conditioning. Ruxin exhaust heat recovery technology. According to different products, it can be divided into: runner type or fixed plate fin type full (sensible) heat exchange heat recovery, coil type heat recovery, heat pump type heat recovery, etc. Others, such as domestic hot water heat recovery of water chillers, etc. Based on the analysis of the energy consumption saved by the above heat recovery methods, generally, the energy consumption of air conditioning power is mainly saved in summer. When the lithium bromide host is used, the energy consumption of air conditioning is saved. Generally, the heat energy consumption of air conditioning is mainly saved in winter. When using natural energy utilization host such as air source heat pump, the energy consumption of air conditioning power is saved. In short, it also has good environmental protection advantages and sustainable development characteristics. Because the heat recovery chiller used series condensers in previous applications, the maximum heat recovery is generally only 30% to 40% of the refrigeration load due to the structural design of the chiller. Moreover, the heat recovery capacity decreases rapidly with the reduction of cooling load, which cannot be provided relatively stably. In addition, the recovered heat energy is generally used for domestic hot water. Due to the instability in the use of domestic hot water, the heat recovery is sometimes non-existent, sometimes high and sometimes low, which has an adverse impact on the operation stability of the unit. Therefore, this kind of heat recovery, although also used as waste heat, has a certain significance of environmental protection and energy conservation, but the savings are small, which also has an adverse impact on the stable operation of the system. However, when a new structure is adopted to make the heat recovery higher and more stable, and the recovered heat energy is used in the air conditioning system itself, the heat consumption of air conditioning heat energy saved by the heat recovery chiller is considerable. Its energy-saving significance can be brought into full play. What this paper explores below is this new field of heat recovery technology and its application. 4. The new heat recovery method of the water chiller (hereinafter referred to as the new method) takes the conventional screw water chiller as an example. Based on the working principle of compression refrigeration, the refrigerant on the evaporator side of the water chiller evaporates and absorbs heat, while the refrigerant on the condenser side condenses and releases heat, and its heat release is greater than the heat absorption of the evaporator. The goal of the new heat recovery method is to recover 100% of the heat release of the condenser for reuse, Thus, the corresponding heat energy consumption of air conditioning can be saved, and the greenhouse gas emissions to the atmospheric environment caused by air conditioning can be reduced. Based on the design of the condenser, the new recovery method of the condensing unit can be named as the integrated parallel condenser (hereinafter referred to as the new condenser). The conventional condenser is a group of coils. After the cooling water absorbs heat, the heat is dissipated into the atmosphere by the cooling tower. Generally, the cooling water is an open system. The so-called integrated parallel condenser refers to a condenser relative to the refrigerant, but from the water side, there are two groups of parallel water coils, one of which corresponds to the working mode of the conventional model, and is an open system, while the other group is a heat recovery coil, which adopts closed circulation. From this structure, it can be seen that any group of coils, as long as they are equipped with sufficient heat exchange area, can absorb all the condensation load. Therefore, the influence of cooling load changes on the production heat recovery of steel welding tensile machine of Jinan new era Gold Testing Instrument Co., Ltd. for many years can be completely eliminated. For example, when the cooling load of the unit decreases to 40% of the full load, the heat recovery can still reach the unit. "Due to the particularity of the mechanical properties of polymer materials and the special use mode of flexible packaging materials, the thickness of the sample tested by flexible packaging materials is very thin, more than 45% of the cooling load."
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