Shandong Shanlan Environment Group Co., Ltd 
Condensation Recovery Principle：
Condensation is an effective method used to recover VOCs. The basic principle is to utilize gaseous pollutants that have different saturated vapor pressures at different temperatures and pressures, and by lowering the temperature or increasing the pressure, certain organics condense out, allowing VOCs to be purified and recovered.
Condensation Recovery Advantages and Disadvantages：
Advantages: The condensation method is to utilize the different recovery of the boiling point of the substance, suitable for organic matter with high boiling point, the method has the advantages of high recovery purity and simple equipment process; and has the advantages of compact equipment, small occupied space, high degree of automation, easy maintenance, good safety, and the output is liquid oil that can be directly utilized, and so on. The biggest advantage is that it can produce economic benefits of recovery.
Disadvantages: the efficiency is generally between 50% and 90%, a single condensation method to meet the standard needs to be reduced to a very low temperature, energy consumption is too large, generally need to be combined with other process technology; condensation method can recover the boiling point of the organic waste gas, the recovery of high volatile organic waste gas recovery is not good.
Scope of application of condensation recovery：
It is suitable for room temperature, high temperature and high concentration, especially suitable for treating high concentration and medium flow VOCs.
Graded matching and control technology:
The condensation temperature and the number of condensation stages are set flexibly according to the characteristics of the VOC medium, so as to reduce the irreversible heat transfer temperature difference by graded cooling, and the condensation temperature of the condensation method recovery device is generally realized according to the steps of pre-cooling, mechanical refrigeration and liquid nitrogen refrigeration. Pre-cooler is a single-stage cooling device, its condensation temperature above the solidification temperature of each component, generally around 4 ℃, the purpose is to make most of the water vapor condensed to water and removed, reducing the device’s operating energy consumption. The volatile gas leaves the pre-cooler and enters the mechanical refrigeration stage, which enables most of the organic waste gas to be condensed into liquid for recovery. If lower cooling temperature is required, liquid nitrogen refrigeration is connected after mechanical refrigeration, which can make the recovery rate of organic exhaust gas reach 99%. The operating temperature range of the single-stage mechanical compression refrigeration unit is -35 to -10℃;Mechanical compression refrigeration units in series consisting of a shallow cooling stage and a deep cooling stage.Its working temperature range is -70℃~-40℃;the working temperature of the deep-cooling device with liquid nitrogen refrigeration can reach -195℃.
Schematic Flow Diagram of Hierarchical Matching Condensation and Control Technology
Staged cooling has the following characteristics:
1.Pioneering multi-stage condensation separate recovery process, solve the problem of oil pressure imbalance
2.Through the different levels of cooperation and start-stop, to achieve the required process, to meet the emission requirements, and improve the adaptability of the device.
3.Reduce the total amount of frost, extend the frost cycle, and promote the long-term stable operation of the device.
4.Reduce the overall energy consumption of the device.
5.Independent compressor, independent temperature control, full redundancy design of refrigeration channel.
6.Intelligent defrost control, fast, effective, pre-cooling in advance, small temperature fluctuations.
