In-depth Analysis of the Energy-saving Principle of the Seven-effect Falling-film Evaporator

The Basic Energy-saving Logic of Multi-effect Evaporation

The multi-effect evaporation of Henan Jiuye Chemical Equipment Co., Ltd. is the core foundation of the energy-saving of the seven-effect falling-film evaporator. In this system, the seven effect bodies are like a precisely coordinated "energy relay team". The first effect evaporator heats the solution to its boiling point under the heating of external steam, and part of the solvent in the solution vaporizes to form secondary steam. These secondary steam are not wasted but serve as the heat source for the next effect evaporator, providing heat for the second effect evaporator. The second effect evaporator uses the secondary steam generated by the first effect to continue evaporating and concentrating the solution. At the same time, it generates new secondary steam and transfers it to the third effect evaporator. This process continues in turn until the seventh effect. In this way, the heat energy of the steam that could only be used once originally is utilized multiple times in the seven effect bodies, greatly improving the utilization rate of energy.

Taking the energy consumption comparison between a traditional single-effect evaporator and a seven-effect falling-film evaporator as an example, when processing the same amount of solution with the same properties, the single-effect evaporator consumes approximately 1.1 to 1.3 tons of raw steam for every 1 ton of water evaporated. In contrast, the seven-effect falling-film evaporator only needs to consume about 0.2 to 0.3 tons of raw steam for every 1 ton of water evaporated, and the energy-saving effect can reach 70% to 80%. This huge gap in energy consumption intuitively reflects the remarkable advantages of multi-effect evaporation in terms of energy conservation.

Cascaded Utilization of Heat Energy and Temperature Level Matching

The energy saving of the seven-effect falling-film evaporator also benefits from its cascaded utilization of heat energy and temperature level matching. During the entire evaporation process, as the effect bodies progress sequentially, the boiling point of the solution gradually decreases. This is because with each effect of evaporation, the pressure within the system gradually decreases. According to the relationship between the boiling point and pressure, when the pressure decreases, the boiling point of the solution also decreases accordingly.

The first effect evaporator operates at a relatively high pressure and temperature, and the generated secondary steam has a relatively high temperature, which can meet the evaporation requirements of the subsequent effect bodies at slightly lower temperatures. As the number of effect bodies increases, the temperature and pressure of the secondary steam gradually decrease, but it can still provide sufficient heat for the next effect evaporator, achieving the full utilization of heat energy.

This design of temperature level matching enables the precise application of heat energy at different temperatures to the evaporation processes with corresponding requirements, thus avoiding the waste of heat energy. For example, when dealing with materials with high concentration and a relatively high boiling point, the early-stage effect bodies can utilize high-temperature steam for preliminary evaporation and concentration. In the later stage, as the concentration of the materials decreases and the boiling point drops, the secondary steam at a lower temperature is used to continue the evaporation process, ensuring that every bit of heat energy is utilized to the maximum extent.

Recompression and Recycling of Secondary Steam

In addition to multi-effect evaporation and the cascaded utilization of heat energy, the seven-effect falling-film evaporator further enhances its energy-saving effect through the recompression and recycling of secondary steam. After being generated, part of the secondary steam will be reinhaled by the jet thermocompressor. After compression, its pressure and temperature are increased, and then it is sent back to the shell side of the first-effect evaporator to participate in the evaporation process as a heat source. This secondary steam recompression technology converts the originally low-grade secondary steam into high-grade heat energy, achieving the recovery and reuse of energy.

Taking a chemical enterprise that uses a seven-effect falling-film evaporator to process chemical solutions as an example, through the secondary steam recompression technology, it can additionally recover an amount of energy equivalent to thousands of tons of standard coal each year. This not only significantly reduces the enterprise's energy consumption costs but also cuts down a large amount of carbon emissions, bringing about remarkable economic and environmental benefits.

Optimized Design to Reduce Heat Loss

The seven-effect falling-film evaporator of Henan Jiuye Chemical Equipment Co., Ltd. also takes fully into account the factors of reducing heat loss in its structural design. Its heating tubes are wrapped with high-efficiency thermal insulation materials, which can effectively reduce the loss of heat to the external environment. The equipment has good sealing performance, reducing the possibility of steam leakage and ensuring that the heat energy is maximally utilized in the evaporation process. In addition, the fluid flow path inside the equipment has been optimized in design, reducing unnecessary resistance and energy loss, and further improving the energy utilization efficiency.

Through the synergistic effect of various energy-saving measures such as multi-effect evaporation, cascaded utilization of heat energy, recompression and recycling of secondary steam, and optimized design, the seven-effect falling-film evaporator has established a set of efficient and energy-saving evaporation systems. Against the backdrop of increasingly tight energy resources and continuously improving environmental protection requirements, in-depth understanding and promotion of the energy-saving principle of the seven-effect falling-film evaporator are of great significance for promoting the sustainable development of industrial production. In the future, with the continuous innovation and improvement of technology, the energy-saving performance of the seven-effect falling-film evaporator of Henan Jiuye Chemical Equipment Co., Ltd. is expected to be further enhanced, bringing greater energy-saving benefits and development space to various industries.