spray dryer cleaning and maintenance are fastidious, these commonly used methods must be kept firmly in mind
September 16, 2020
spray dryer cleaning and maintenance are fastidious, these commonly used methods must be kept firmly in mind.
Spray dryer is a device that can dry and granulate at the same time. It mainly consists of slurry supply system, atomizer, drying tower, hot air system, exhaust gas and dust removal system, unloading and powder conveying system.
Spray dryer is also a continuous atmospheric dryer, which is used for drying thermosensitive liquids, suspensions and viscous liquids, and also for drying fuels, intermediates, soap powder and inorganic salts.
At present, pharmaceutical enterprises pay more and more attention to the cleaning and maintenance of pharmaceutical equipment, but different pharmaceutical equipment have different cleaning methods.
Take the centrifugal spray dryer as an example, after using the centrifugal spray dryer, to ensure the next normal use, users need to clean and maintain the centrifugal sprinkler.
I understand that at present, there are three kinds of cleaning methods for centrifugal sprayer, namely dry cleaning, wet cleaning and chemical washing. Among them, dry cleaning mainly refers to the use of brushes, brooms, vacuum cleaners, etc. Chemical washing method can be divided into alkali solution, acid solution and various detergents.
The so-called wet washing is not literally a simple water or disinfectant for washing. According to the drying equipment manufacturers, wet washing refers to the use of hot water in the range of sixty to eighty degrees Celsius, the centrifugal spray dryer spray nozzle cleaning, the scope of the hot water can ensure that the nozzle is cleaned and sterilized more thoroughly.
In fact, in addition to the above-mentioned several methods, there are acid washing and alkaline washing and other chemical cleaning methods. Among them, pickling refers to the nitric acid in accordance with the concentration of 1-2% after the solution is prepared and heated.
Alkaline washing refers to mixing sodium hydroxide into 0.5-1% concentration solution, then heating to 60-80 ℃ to wash it, and then use clean water to wash it.
It should be reminded that when the staff are cleaning the centrifugal sprinkler, we should pay attention to the protection measures for the centrifugal spray dryer and the centrifugal sprinkler, and not use chlorine and its compounds to wash, so as to avoid oxidation.
In addition, if there are some faults, the operators should solve them in time, so as not to reduce the service life spray dryer. If wet powder is adhered to the inner wall of the main tower, it is likely that the feeding speed of the material is too fast and the amount is too large, resulting in the failure to completely dry. The solution is to slow down the feeding speed and quantity, and properly adjust the feed pump.
It may also be that the operator did not operate according to the instructions. The main tower was not heated. The solution was to increase the inlet and outlet temperature of the spray dryer.
If there is a lot of impurities in the product, it is indicated that the impurities in the spray dryer material are not filtered out during the filtration process. The air filter can be checked and the filter net can be replaced according to the situation.
It is also possible that the purity of the material liquid is not high, so the sample test can be carried out on the material liquid, and the impurities in the material liquid can be filtered out. It is also possible that there are impurities in the equipment, and the operators need to clean the equipment comprehensively on a regular basis to remove impurities.
There are two main reasons for the low recovery rate of the product. One is that the cyclone separator has problems. The solution is to check the cyclone separator to see if there is a gap and whether the air tightness is in good condition. Second, the dust removal performance is low, and the manufacturer suggests that the secondary dust removal can be appropriately increased.