In the pharmaceutical manufacturing industry, energy consumption has always been an important part of production costs, while the waste heat generated during the production process is often overlooked. In fact, the application of waste heat recovery technology can not only significantly reduce energy expenses, but also reduce carbon emissions, helping enterprises achieve green and sustainable development.
Sources and recovery processes of waste heat in pharmaceutical manufacturing
Pharmaceutical production involves multiple high-temperature and high-pressure links. If the waste heat generated in these links is reasonably recovered, the energy utilization rate can be greatly improved. The following are the five main sources of waste heat and their recovery scenarios:
Steam condensate from raw material cooking
During the cooking process of pharmaceutical raw materials, high-temperature steam releases a large amount of heat energy to form condensate, and the temperature is usually maintained above 80°C. By installing a shell-and-tube heat exchanger, the waste heat in the condensate can be used to preheat the boiler inlet water or the plant heating system, reducing the consumption of new energy required for steam generation.
Waste gas from drying and granulation processes
The drying and granulation processes will produce high-temperature waste gas (about 100~150°C), and direct emission will cause energy waste. Finned tube heat exchangers can be used to recover the heat in the exhaust gas and use it to preheat the air entering the dryer, reducing heating energy consumption. In addition, the recovered heat can also be used in other low-temperature process links, such as pre-drying of raw materials.
Reactor cooling water
In drug synthesis reactions, the reactor often needs to be temperature-controlled by cooling water. After the cooling water absorbs heat, the temperature rises (up to 50~70℃). If it is directly discharged or circulated for cooling, a lot of heat energy will be wasted. Through the waste heat recovery system, this part of the heat energy can be transferred to the purified water system or cleaning process that needs to be heated, realizing the cascade utilization of energy.
Boiler flue gas
The flue gas temperature discharged during boiler operation is usually as high as 200℃ or above, which contains rich waste heat. Using a heat exchanger to recover the waste heat of the flue gas can preheat the air or production water required for boiler combustion, significantly improve the thermal efficiency of the boiler, and reduce fuel consumption and ammonia oxide emissions.
Sterilizer exhaust gas
The sterilization process uses high-temperature steam to kill microorganisms, and the temperature of the waste gas generated can reach above 120℃. Through the waste heat recovery device, the waste gas heat energy can be converted into clean steam and reused in the preheating stage of the sterilization cabinet itself or other equipment, forming a closed-loop energy-saving mode.