As important way to save energy and improve the environment and a key infrastructure for the development of economy and society of the city, district heating is the symbol of modern cities. Because of the continuous economic growth and the demand for better living environment, the district heating industry has been developed rapidly, becoming a major heating approach. The priority problems that need to be addressed in the heating industry involve energy saving, environmental protection, cost reduction and efficiency improvement. The optimal design of district heating system and the progress of the heating technologies are preconditions for the sustainable development of district heating and for attaining the best environment with the most economical energy consumption.
Adopting the advanced technologies and equipment, new and high-tech materials and products with high power and efficiency and low energy consumption is a key measure to save energy. THT has always been paying attention to the development of heating industry. Over the past 20 plus years, it has been committed to studying and disseminating the intensified heat transmission technologies, creating value for our clients, saving tremendous energy and greatly reducing the metal consumption. THT has evolved from providing the efficient plate heat exchangers to automatic duty-free pre-assembly integrated heat exchange station. In 1991, THT developed the patented uneven cross-section heat exchanger. Later, it developed the pressure-separated heat exchange station high-pressure plate heat exchanger. All of these achievements have provided the technological progress of district heating with advanced equipment guarantee and professional solutions.
In the district heating industry, the uneven cross-section plate heat exchangers are widely used, in which the heat transmission plates have such design that the cross-sections of the runner passage on the two sides is uneven with the diversion corrugation.
In this design, the plate that has larger cross-section constitutes the wide runner while the one with the smaller cross-section constitutes the narrow runner. The ratio of the two cross-sections is 2:1. Correspondingly, the angular holes in the plates are different. The agents with larger flow pass the larger angular hole and wide runner while those with smaller flow pass the smaller angular hole and narrow runner. While having the features of even cross-section plate heat exchanger, the uneven cross-section plate heat exchanger has the following characteristics:£º ¡¤Greaten heat transmission capability: Because of its special structure, the heat exchanger is particularly suitable for the working conditions in which the treatment capacity on the hot and cool sides is ¡İ2:1. Due to the 2:1 ratio of the runner cross-section, in the single flow path, the plate spacing flowing speed of the cold and hot agents is similar or the same. In this way, the heat transmission coefficient is raised. In other words, the heat exchange capability of the plate heat exchanger is improved. ¡¤Lower investment cost: When the treatment capacity of the hot and cool agents is ¡İ2:1, the heat transmission coefficient of the uneven cross-section heat exchanger can be raised by 20% to 30% compared with that of common even cross-section heat exchanger, which means the heat exchanger surface can be reducedby 20% to 30%. As a result, the equipment cost can be reduced. ¡¤Smaller pressure loss: Because the uneven cross-section plate heat exchanger usually adopts the single flow path and the heat transmission plates employ the uneven cross-section running layout, the plate spacing flowing speed is more rational than that of even cross-section type. As a result, the pressure loss is decreased.
¡¤Easier to be used: Because the uneven cross-section heat exchanger usually adopts the single flow path, the tube opening is on one side of the fixed plate and the flexible plate is not fixed, it is easy and convenient for the clients to install, debug, combine, alter, clean and repair the heat exchanger.
Nowadays, more and more district heating projects are beginning to make use of the waste heat produced by the thermal power plants. The cooperation between the power plants and the heat suppliers has become a widely accepted way to save energy. As a major equipment in such cooperation, the heat supply network heater uses the extraction steam (usually the 4th or 5th section of the extraction steam with the steam pressure at between 0.2-0.6 Mpa ) of the turbine as the heat source to heat the heat supply network water. As a result, the performance reliability, advanced and rational design and economical investment of the heat supply network heater have become the never-changing pursuit of the manufacturers.