噴霧干燥技術在口服固體制劑生產中的應用

1、the spray drying technology with the spray method, make the material to droplet disperse in the hot air f 1 ow, full contact materials and hot air, heat and mass transfer process in an instant, the solvent (ineluding water and organic solvent) quickly evaporated into gas, to achieve the purpose of d

2、rying the spray drying technology is widely used in the pharmaceutical industry in china, in the field of oral solid preparation, commonly used in high sensitive drugs and feed liquid concentration during the process of decomposition of drug drying. the product has fine particle size, uniform distri

3、bution, good fluidity and quick dissolving propertycharacteristics and classification of spray dryerspray dryer is a kind of drying equipment which directly dry the solution or suspension into solid particles the drying product can be directly obtained from the feed liquid, and the unit operation su

4、ch as evaporation, crystallization, separation and pulverization can be avoided, and the product can be continuously and automatically produced, and the operation is stable the drying methods, spray dryer gas-solid contact surface area, short drying time, dry time is 530s,suitable for drying heat se

5、nsitive materials the dried product has good quality and can obtain 3050 micron m particles the product has good fluidity and instant solubility the disadvantage is that the dryer has large volume and low heat transfer coefficient, resulting in low thermal efficiency and large power consumption.ther

6、e are many kinds of classification methods of spray dryer,gas-liquid flow in flow, and can be divided into countercurrent and francis; according to installation of the atomizer can be divided into spray type, spray type： according to the structure of the atomizer can be divided into centrifugal, pre

7、ssure and airflow; according to whether gas heating cycle can be divided into open and closed type, partial circulationthe basic process of spray drying (closed type)the material is atomized by atomizer and dispersed into small drying chamber at the same time, the heated gas is sent into the heater

8、by the blower and then heated into the drying chamber. the mixture of liquid droplets and hot gas is fully mixed and contacted in the drying chamber. the liquid in the droplet instantly evaporates into gas, and the material is dried into tiny particles the mixed gas and solid two phase fan is sucked

9、 into the cyclone separator, the two phases are separated, the solid material is settled to the bottom collector, and the gas phase is sent to the dust filter to capture the escaping materia1. after the gas phase is condensed by the condenser, the solvent carried by the gas phase is changed into liq

10、uid and can be collected and used as a carrier after being dried, the gas is recycled in the system the flow chart is as follows:process requirements for oral bulk drugoral solid preparation of different kinds of specific process requirements are also different, in the process of spray drying machin

11、e design and manufacture, the best do different design for different varieties, in order to achieve the best state of equipment and technology to adapt the some requirements listed below are often mentioned in the selection of spray dryers for solid formulations:1. clean requirements (the following

12、7 headings should be changed into italics)the main process of the production of api must be carried out in the clean environment of grade one hundred thousand spray drying is an important process of quality contro1. the parts of the contact material in the spray dryer should be made of stainless ste

13、e1. for the material with strong acid corrosion, it is better to use 316l stainless stee1. the parts which are directly contacted with the material, such as drying chamber, cyclone separator and filter, should be smooth in inner wall, no dead angle, easy to be cleaned, easy to disassemble and easy t

14、o clea.n. spray dryer is often a huge system, and therefore can not be put in the overall clean area, often only will collect the materials into the clean area, this system requires good airtight performance, so as to prevent the external pollution not system2. avoid sticking to the wallthe sticking

15、 wall phenomenon is still a prominent problem that hinders the normal operation of spray dryer the spray drying process of solid preparations (especially chinese herbal medicine) is especially obvious the sticky wall of material is not only harmful to collection operation, but also the sensitive wal

16、l material will deteriorate and become unqualified material with the extension of time. from the perspective of technology solutions including selecting suitable solvent, adding accessories, changing the process parameters, but these methods can adjust the room is not large, so we must seek the fund

17、amental solution from the point of equipmentthe sticking and caking problems in drying process were studied by experts both at home and abroad it was agreed that the main reason for sticking wall was wall temperature five possible ways to prevent wall sticking are listed below:a wall drying tower is

18、 adopted, in which the air is cooled so as to keep the wall temperature below 50 degrees;introducing two times air cooling tower wall through the tangential plate of the tower wall;a gas broom consisting of a row of nozzles is installed near the wall of the tower and slowly rotating along the wall o

19、f the tower;* the tower wall increased by air hammer, hammer percussion, force the material from sticking to the wall;increase the machining accuracy, and the polishing of the inner wall of the tower can also reduce the adhesion of the wal 1.3. automatic control performancespray drying is a continuo

20、us production process with more control points fot example, closed loop control system includes: feed concentration, feedrate, inlet velocity, inlet temperature, system pressure, various components of differential pressure and gas purity detection and so on, rely on traditional manual adjustment is

21、very difficult a set of good automatic control system can make the whole spray drying system run smoothly, reduce the unqualified rate of products, reduce the hidden danger of safety at present, domestic products in automatic control is relatively backward, and some foreign advanced equipment, such

22、as the danish company nehru spray dryer in automatic control technology has been very mature4. drying effectdue to the need to further complete the preparation process of oral api, the physical properties of spray drying products are different in terms of improving the preparation effect and taking

23、the absorption effect of the final medicine first of all, moisture content is the first indicator of drying products, generally required to control in a certain range, not too high or too low. secondly, the volume of the drug is generally controlled according to the volume, which requires the stabil

24、ity of the heap density of the product, and the liquidity of the product is better oral granules often require instant solubility in general, changing the atomization dispersion or changing the operating conditions to control the drying rate can be used to produce products with different bulk densit

25、ies, but the range of variation is limited. one of the techniques that is worth mentioning in improving the physical properties is foam spray drying, which is to start the foaming of the feed liquid and then spray drying this method was originally proposed to improve the thermal efficiency, and late

26、r was used to adjust the physical properties of the products it has been proved that the product prepared by foam spray drying has large particle size, porous, multi concave, rough surface, and has good instant solubility in addition, oral api also has some special requirements, such as: particle sh

27、ape some require spherical particles, uniform particle size in general, different shapes of particles can be obtained by changing the atomization method before choosing the spray dryer, it is better for the raw material manufacturers to carry out the parameter optimization experiment with the help o

28、f the equipment manufacturing enterprises to determine the best combination of parameters to ensure the drying effect of the medicine5. protective measuresdue to the different nature of the drugs, some higher requirements are also put forward for the protection design of the equipment when the mater

29、ial is dissolved in organic solvent, the whole system must meet the requirements of explosion protection when drying in the motor, instrumentation, control valves and other accessories design should choose explosion-proof type in addition, in order to prevent the mixture of solvent and air as explos

30、ive gas, the system can not use open type, but must adopt the closed cycle system, and the carrier should use inert gas, such as nitrogen. in addition, the closed circulation system using nitrogen as the carrier is needed for the drying of some oxidizable materials6. environmental protectionthe prod

31、uct of spray drying for fine particles, in order to meet the requirements of environmental protection, spray drying system with cyclone separation products, exhaust gas purification is not enough, but also with the general purifying bag type dust collector, the exhaust gas dust content is lower than

32、 50mg/ (nm) 3 gas; or use wet scrubber, the exhaust gas the quantity of dust is reduced to 15 35mg/ (nm) 3 gas when using nittogen as carrier, the system should pay attention to airtight, the exhaust port should be taken to the outside7. reduce coststhe inlet temperature of hot air is 250500 degrees centigrade in parallel flow operation,t