In China, the waste gas and cooling water waste heat resources, which currently account for nearly 55% of the calorific value of gas generator unit fuel, are basically wasted. The waste heat utilization technology of gas generator units is to achieve a system that fully utilizes the originally wasted heat resources.
With the improvement of people's quality of life, refrigeration and heating are becoming increasingly popular, and energy consumption is increasing. At the same time, the waste heat resources of gas generator units have not been comprehensively utilized, consuming a large amount of energy. Based on the current situation of waste heat utilization in gas power generation units, our company has utilized its technological advantages to develop a set of gas unit flue gas waste heat utilization supporting heat pipe waste heat boiler and heat pipe heat exchanger. The generated superheated steam and hot water are used for waste heat power generation and internal cooling, heating, and power supply within the enterprise.
At the same time as generating electricity from the gas turbine, the heat from the exhaust gas of the unit is used as the energy source. The flue gas passes through the heat pipe waste heat boiler and heat exchanger, heating the medium water. The superheated steam generated by the heat pipe waste heat boiler is used for waste heat power generation, and the hot water generated by the heat pipe heat exchanger is cooled or heated by the lithium bromide chiller. The system principle is shown in the following figure:
Flow diagram of waste heat refrigeration and heating system
The comprehensive utilization of thermal energy from gas generator units mainly starts from three aspects: power supply, heating and bathing, and summer air conditioning and refrigeration. In the design process of comprehensive utilization, the following factors should be fully considered:
a. The utilization should avoid having a significant impact on the performance of the gas generator unit, that is, not affecting the normal operation and power output of the gas generator unit;
b. The distance between the exhaust main pipe and the waste heat utilization system should be as short as possible, and full consideration should be given to the insulation and insulation of the exhaust pipe to reduce heat loss from the exhaust outlet of the gas generator unit to the heat pipe waste heat boiler;
c. It is necessary to consider the impact on waste heat power generation, waste heat cooling, and heating caused by load changes of gas generator units, in order to avoid excessive cooling (or heating) or insufficient capacity due to load changes;
d. Considering the large control range, multiple items, and high operational difficulty of the entire process, the entire system should implement electrical automation control and monitoring as much as possible;
e. The entire system should fully consider the safety of maintenance operations and use.