Dirty in the heat exchanger of a LiBr absorption system is a common and serious issue that significantly affects the system's performance and operational reliability. Dirty primarily forms on the inner walls of heat exchanger tubes that come into contact with cooling water or chilled water (typically in the condenser, absorber, and evaporator; the generator may also be affected, depending on the type of heat source).

The primary impacts of dirty includes:  

1. Significant reduction in heat transfer efficiency:  

The thermal conductivity of dirty is far lower than that of metal tube walls (typically only a fraction of the metal's thermal conductivity).  

Scale forms an insulating layer on the tube walls, significantly increasing thermal resistance.

This prevents heat (or cold) from being effectively transferred.

2. Reduced cooling/heating capacity of the unit:

Due to the decrease in heat transfer efficiency, the evaporation capacity of the evaporator weakens, resulting in a significant reduction in the cooling (or heating) capacity output by the unit. The unit cannot meet the design load and fails to satisfy the heating and cooling needs of end-users.

3. Increased energy consumption and rising operating costs:

To compensate for the loss of cooling/heating capacity due to scaling, the unit must consume more high-grade energy (such as steam, natural gas, or hot water) to drive the cycle. The unit's performance coefficient significantly decreases.

The power consumption of pumps (cooling water pumps, chilled water pumps) also increases due to increased system resistance (partial blockage) or increased flow requirements (to compensate for performance). Overall operating costs (energy expenses) significantly rise.

In summary, the hazards of scaling in LiBr absorption unit heat exchangers are multifaceted: it directly weakens the core heat transfer capacity, leading to insufficient unit output, plummeting efficiency, and soaring energy consumption, while also laying the groundwork for accelerated corrosion and frequent failures, ultimately significantly increasing operating and maintenance costs. Therefore, strict water quality management (including makeup water treatment and circulating water treatment, such as chemical dosing, softening, and filtration) and regular inspection and cleaning of heat exchanger tubes are critical measures to ensure the efficient, stable, and long-term operation of LiBr absorption units.