1.What is zero emission of steam?
The brewery'ssaccharification workshop is a big energy consumer, and its thermal energy consumption accounts for more than 50% of the entire plant's energy consumption. In the past, the 6 pots, including the gelatinization pot, saccharification pot, filter tank, temporary storage tank, boiling pot, and precipitation tank in the brewery saccharification workshop, produced a large amount of secondary steam during the production process. These high-energy exhaust gases are not only realized in the boiling pot. Except for part of the recycling, all of them are vented into the atmosphere through the exhaust tube. It is a pity that there is no recycling. The so-called zero emission means that all the secondary steam discharged in the saccharification process is recovered and utilized, and no steam is discharged, so that the entire saccharification plant can achieve zero emission of steam.So, what is the disadvantage of saccharification secondary steam venting?First, pollute the environment. The exhausted waste steam has the smell of rotten sweet potatoes, which seriously pollutes the brewery and the surrounding environment.Second, increase carbon emissions. Evacuation of a large amount of secondary steam increases carbon emissions, enhances the greenhouse heating effect, and promotes atmospheric warming. As the earth's temperature rises, there is a contribution to the evacuation of secondary steam from brewery saccharification.In 2015, it successfully recovered all the secondary steam from saccharification, achieved zero emissions, and became the first person in China to eat crabs. This is a welcome technological advancement in the Chinese beer industry. Its significance is that China has achieved a gratifying result in its march from a major beer country to a powerful beer country.
2. How to achieve zero emissions?
First connect the exhaust cylinders of the 6 saccharification pots together, and then divide them into 3 areas with 2 pneumatic valves: the first area is the gelatinization pot, saccharification pot, filter tank, and temporary storage tank 4 pots, because of this part The working temperature of the materials is between 70℃~100℃, which are relatively similar and will not affect each other.
The second area is the boiling pot. The boiling pot will generate a large amount of secondary steam, and a special secondary steam condenser is required to absorb this part of heat.The third area is the end of the sedimentation tank.Each area is equipped with a separate water-sealing tank for conditional connected breathing with the outside world.
Each area is equipped with a separate vacuum valve, pressure transmitter, and pressure relief valve. The function of the water-sealed tank is to realize mechanical dissolution regardless of the formation of a vacuum in the sealed space or the formation of overpressure; the function of the pressure transmitter is to automatically open the pressure relief valve to exhaust steam when the program detects the overpressure, and when the program detects the vacuum The vacuum valve is automatically opened to inhale. The above two designs form a double protection for the sealed space of the pot body, including mechanical water-sealing protection and software program protection. Through automatic control system technology, zero emission of saccharification secondary steam can be achieved.
3. The working principle of achieving zero emissions
Taking the saccharification pot as an example, the saccharification pot has several main steps such as feeding, heating, stopping, and transferring to the filter tank.When feeding, as the liquid level in the saccharification pot rises, the gas in the upper part of the pot is discharged. These gases are first discharged to other boilers through the exhaust pipe connecting pipe. When other boiler steam fills the space, the pressure in the sealed space will increase. When the pressure is higher than the pressure that the water sealed tank can withstand, the water seal will be broken. Release into the atmosphere. However, because there is a spray ball on the top of the water seal tank, and the spray is always circulating, even if the water seal is broken, all the secondary steam will be absorbed by the water under the spray ball, as long as it can dissolve in the smell of water Will be washed and adsorbed in the water, and only non-condensable gas will be discharged into the atmosphere, realizing zero emission.When the temperature rises, similarly, some secondary steam will be generated during the heating stage. These secondary steam will first run to other pots. When the gas has nowhere to escape, the pressure in the sealed space will be higher than the pressure of the water-sealed tank. The water seal will be broken again, and the secondary steam will be absorbed by the water from the spray ball. The non-condensable gas is discharged into the atmosphere. When the pressure ceases, the steam neither exhausts nor inhales, reaching equilibrium.When the mashing pot is mashed to the filter tank, the liquid level of the saccharification pot needs to be sucked in, and the liquid level of the filter tank rises and needs to be exhausted. The two pots are connected, so they are mutually ventilated and balanced. In this way, the entire production process of the saccharification pot has achieved zero emissions.Transform the existing saccharification equipment:
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Connect the exhaust cylinders of the 6 saccharification pots together, and then divide them into three areas with 2 pneumatic valves.
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Each area is equipped with a separate water sealing tank.
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Each area is equipped with a separate vacuum valve, pressure transmitter, and pressure relief valve.
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To prevent overpressure and vacuuming, special attention should be paid to preventing vacuuming, forming negative pressure, and evacuating the pot.
The process of filter tank and temporary storage tank is the same. When the temporary storage tank needs to transfer the wort to the boiling pot, open the pneumatic valve between the two boiler exhaust cylinders, and the gas will reach equilibrium through communication. Because the boiling pot is equipped with a separate secondary steam condenser, the secondary steam generated during the heating, preheating, and boiling phases transfers heat to the thermal water through this condenser. Only when the temperature of the thermal water is too high cannot When the excess heat is completely absorbed, it will be discharged to the water-sealed tank, and the heat will be absorbed by the water-sealed tank and the spray ball on the top of the water-sealed tank.When the boiling pot needs to be transferred to the sedimentation tank, the factory can open the pneumatic butterfly valve between the two pots to communicate with each other to balance the gas. During the resting phase of the sedimentation tank, no air is inhaled or exhausted. When cooling is required to send the gas to the fermentation tank, the sedimentation tank needs to be inhaled. At this time, the vacuum valve can be opened intermittently according to the pressure in the tank to prevent the generation of vacuum.In this way, in all the above process steps, the secondary steam will not be directly discharged into the atmosphere, and the various tanks will digest each other, or only discharge some non-condensable gas, and finally achieve the goal of zero emission.
