Glycol heat exchanger
Glycol heat exchanger
Principle:
The heat exchanger and glycol solution are used as the heat exchange medium to transfer the cooling capacity (heat) in the exhaust air to glycol solution through the heat exchanger at the exhaust side to reduce (increase) the temperature of glycol solution, and then the cooled (heated) glycol solution is delivered to the heat exchanger at the fresh air side through the circulating pump to reduce (increase) the temperature of fresh air, reduce the load of the system and the whole air conditioning system The operating cost of the system.
Construction:
It is composed of the heat exchanger at the exhaust side and the heat exchanger at the fresh air side. The two heat exchangers are directly connected through the glycol pipe and circulates through the circulating pump. Because of the existence of the carrier refrigerant glycol, glycol has certain volatility and toxicity, and it is a flammable liquid, which has potential leakage.
characteristic:
Indirect energy recovery (sensible heat) type has many heat transfer media in the middle and low heat transfer efficiency. The sensible heat efficiency is generally only 30-40%, and the maximum is only 45%. Basically, there is no latent heat recovery (temperature exchange efficiency).
In terms of structure and working principle, it is difficult to maintain and repair, with high maintenance cost and hidden danger.
Because there are many connecting parts, complex structure and many connecting parts. The leakage of connecting pipes, the quality of heat exchange medium, the quality of heat exchanger, the quality of pipeline circulating pump can form the hidden trouble of the whole air conditioning system.
As a functional section of the air conditioning box, it can be installed up and down or left and right. It is more suitable for the air supply and exhaust system of remote end treatment, where the air supply and exhaust must be completely isolated. The maximum surface wind speed that can bear is 2.8m/s, which takes up a large space. Because the freezing point of 15% glycol aqueous solution is only about - 5.4 ℃, in order to better ensure its system operation, the recommended method is as follows:
1. Monitor the temperature of the air conditioner room. When the temperature of the air conditioner room is lower than 0C, measures shall be taken in time to prevent the temperature from falling further;
2. For the commissioning unit with glycol heat recovery system that is not in operation temporarily, it is recommended to close all its fresh air valves to prevent fresh air with reduced outdoor temperature from entering the air conditioning phase;
3. If the outdoor temperature is lower than 5 ℃, it is recommended to turn on the glycol heat recovery device before starting the unit, make its internal solution run, and then start the unit, so as to carry the risk of its solidification;
4. Since glycol solution will volatilize and deteriorate during operation, resulting in its concentration decreasing and solution freezing point increasing, it is recommended that operators regularly detect the change of ethanol concentration, timely supplement and reduce the risk of system icing.
