The Case of Using Condensate Water


Central heating has strong seasonally for condensate water using, condensate water pipes will be non-occupation for a long time, it’s difficult for power plants to recycle qualified condensate water, and investment recovery ratio is very low, so the power plant will drain the unqualified Condensate water commonly, it’s too much waste for draining such a huge amount of Condensate water. We are in the age of scarce water resources, to improve the heating efficiency, we should apply way widely, and to make full use of these steam condensate water.


Below are some try using of condensate water,


1) To be used as filling up water in heating water circulation system. Condensate water quality is better than heating circulation system water, and with a certain temperature, it’s good as a secondary network filling up water, and can be unified deployment when used between different thermal sub-stations.

2) To be used as heating source to small area nearby.

3) To be used as a bath after short processing.

4) To be raw materials of pure water after certain treatment.

5) To supply warm water for swimming pool in winter.

6) To be used in heating air condition.


The operation of the power station are complying with the adjustment of the whole central heating system, condensation water using is complying with the unified deployment, too. To improve the operation efficiency and economic benefit of the whole system, we need to have the concept of overall, safety as well as economic.


Prefabricated insulated piping mandatory limits the water temperature of plastic material, also limits the service life of pipelines.


During the working life, the system need the heat preservation material better performance on compressive strength and better bond properties compressive strength with steel pipe and the outer casing. Tension and deformation conditions are depends on the working conditions, temperature and pressure, and also take corresponding technical measures depends on the condition of pipeline buried. In addition, the polyethylene vinegar insulation materials and the polyurethane thermal casing has big influence on the life of the heating pipe, we choose ammoniac vinegar bubble to analysis these two performances of the materials, which are heat resistance performance and compressive strength performance.


I. Heat resistance performance of European EN253 standard prefabricated insulated piping life must be at least 30 years when in normal working temperature 120 condition.

If we assume that the highest water temperature is 110 for the rest of the year, then the entire system life is 75 years and accord with EN253 standards. But, the 75 years life does not mean that the prefabricated insulated piping do not need any require maintenance during heating, it only means that polyurethane heat preservation vinegar material is expected to remain its strength performance during the period. In addition, when design a district heating system, use period of fatigue calculation assumes that a number of load cycles - temperature changes should be considered from the working temperature to the soil temperature then back to working temperature. Although polyamine vinegar heat preservation material keep the performance in a fairly long period, but the load cycle continues. Therefore, must ensure that the district heating pipes in every day’s running is less than the design allows conditions facing the load cycle changes.


II. The compressive strength finite of polyurethane insulation materials will limited the compressive strength of vinegar limits the buried depth of pipeline and related usually buried conditions standards. Tests have confirmed that when the density of polyurethane foam vinegar is 75 kg/m3, it exposed to a temperature of 140 environment at about 15months, its compressive strength will turn to zero. The compressive strength values in about two years later will be still the same as the new polyurethane foam vinegar when the temperature exceeds 125 . We need pay special attention to directionality changing, such as pipe bend or branch, thermal insulation material compressive strength finite will limited the maximum pipe buried standard.