We all know that the fermentation of beer requires a lower temperature, and during the fermentation process, the metabolic activity of the yeast will increase the temperature in the tank, so artificial control is required to make the temperature suitable throughout the fermentation process.
In this post, I will explain how the fermenter can control temperature.
1. Cooling method
First, let’s take a look at the two cooling methods of conical tanks: indirect cooling and direct cooling. The refrigerant used in the indirect cooling method is a mixture of ethanol or ethylene glycol and water. It is cooled in the evaporator box of the ammonia refrigerator. The temperature is generally controlled at about -5°C. The refrigerant flows in from below and flows out from above. The direct cooling method means that the liquid ammonia evaporates and absorbs heat directly in the cooling jacket of the conical tank to cool the wine in the fermentation tank. Liquid ammonia enters from above through the distribution pipe and flows downward.
2. the comparison of two cooling methods
Compared with the indirect cooling method using ethanol or ethylene glycol, the direct evaporative cooling of liquid ammonia has the following advantages:
(1) Saving energy by about 20%, the working temperature of the compressor with direct evaporation only needs to be about -5 °C, while when the indirect cooling method is used, the compressor needs to work at a much lower temperature, which makes the refrigerator work. Cooling capacity is low. In addition, the delivery volume of refrigerant liquid ammonia is also much less.
(2) Less equipment is required. Compared with indirect cooling, direct cooling saves the alcohol water or glycol water required for the evaporation of liquid ammonia, and also saves the evaporator.
(3) Less thermal insulation material is required and installation cost is low. As the flow of liquid ammonia is reduced, the diameter of the pipes used becomes smaller, and the number of containers is reduced, which reduces the consumption of thermal insulation materials and saves installation costs.
3. Precautions for using liquid ammonia
Due to the many significant advantages of the direct cooling method, more and more breweries have adopted the method of direct evaporative cooling of liquid ammonia. However, in the craft brewing industry, there are still many breweries that use the indirect cooling method of ethanol or glycol. This is because when using direct cooling, extra attention needs to be paid to its safety.
Liquid ammonia is a pungent and toxic substance, which is flammable and explosive under certain conditions, so its safety must be considered in equipment design. Secondly, the working pressure of liquid ammonia is high and the permeability is strong, so the welding quality of the jacket of the fermentation tank is extremely high. Pay attention to the structural design of the jacket, and ensure that the welding is good everywhere, and there must be no leakage of liquid ammonia, otherwise serious quality and safety problems will occur.
Therefore, if you plan to use liquid ammonia direct evaporative cooling to cool your brewery fermentation tanks, be sure to find a reliable manufacturer to buy high-quality brewery brewing equipment.
The above is the relevant content of the temperature control of the conical fermentation tank in the craft beer equipment! Welcome everyone to discuss the knowledge of craft beer with me! If you need beer brewing equipment or plan to build your own brewery, please contact China Vdo Machinery (JINAN) Co., Ltd.
Understanding Temperature Control Systems in Craft Beer Equipment