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2設(shè)備參數(shù)對中藥有機(jī)溶劑噴霧干燥機(jī)粘壁性的影響  噴霧干燥是流化干燥技術(shù)用于液體物料的一種較好的方法，其流程是利用霧化器將一定濃度的液體物料噴射成霧狀液滴，在干燥的介質(zhì)中進(jìn)行熱交換使霧狀液滴中的溶劑迅速蒸發(fā)，獲得粉狀和顆粒狀制品。中藥成分因理化性質(zhì)不同，其傳質(zhì)和傳熱的速率也存在較大差異，造成不同程度粘壁現(xiàn)象。在充分掌握中藥提取物的理化性質(zhì)的前提下，通過調(diào)整噴霧干燥設(shè)備的參數(shù)可改善粘壁的情況。 

2．1 有機(jī)溶劑噴霧干燥機(jī)噴嘴安裝  在噴霧干燥過程中，增加物料的分散度，可加速傳熱和傳質(zhì)過程。噴嘴的安裝對噴霧設(shè)備是非常重要的。當(dāng)霧滴群離開噴嘴時(shí)，其形狀是個(gè)被壓縮空氣心充滿的錐形薄膜，霧滴應(yīng)均勻分布在噴霧錐中；噴霧錐是對稱的，如果不同心就會偏離中心線，進(jìn)而影響霧化效果，導(dǎo)致霧滴直徑增大，嚴(yán)重時(shí)會出現(xiàn)液線，造成粘壁現(xiàn)象。因此，在使用的過程中必須保證同心度。

 2．2 熱風(fēng)量  風(fēng)量控制的好壞，zui終體現(xiàn)在干燥物料的含水量，與粘壁有直接的關(guān)系。由于噴霧干燥過程是在微負(fù)壓下操作，霧滴能否達(dá)到干燥效果并抽走干燥物料取決于熱風(fēng)量。同時(shí)霧滴直徑大小可用熱風(fēng)量來調(diào)節(jié)。隨著熱風(fēng)量的增加，霧滴直徑減小，干燥加快，粘壁的可能就相對減小。但氣流量過大，所得粉體的吸濕性增強(qiáng)，噴霧過程中會發(fā)生粘壁現(xiàn)象；氣流量過小，導(dǎo)致霧徑偏大，干燥不充分，發(fā)生粘壁現(xiàn)象。

 2．3有機(jī)溶劑噴霧干燥機(jī)進(jìn)風(fēng)溫度  進(jìn)風(fēng)溫度的高低，也是影響粘壁性的主要因素。研究表明：如果在開啟設(shè)備時(shí)就將空氣加熱器全開，這樣就會造成出口溫度很快上升，而實(shí)際塔體溫度并沒有均衡升上來．溫度不均勻，此時(shí)開始噴霧就很容易產(chǎn)生粘壁現(xiàn)象。若溫度過高，會對中藥有效成分造成破壞或者改變某種成分的性質(zhì)；溫度過低，不能充分干燥，發(fā)生粘壁現(xiàn)象。在適宜的范圍內(nèi)，進(jìn)風(fēng)溫度越高，溶劑蒸發(fā)越快，粘壁現(xiàn)象減輕。如果中藥浸膏含粘性成分較多，應(yīng)適當(dāng)降低進(jìn)風(fēng)溫度和出風(fēng)溫度，這樣就能使噴霧干燥順利進(jìn)行，因?yàn)樘穷惓煞质芨邿岷笳承栽黾樱畡t產(chǎn)生粘壁現(xiàn)象，適當(dāng)降低溫度則可減輕粘壁情況。

 2．4供液速度  供液速度與粘壁現(xiàn)象的發(fā)生也有重要。在其他條件沒有改變的情況下，供液速度加快，會導(dǎo)致霧滴未處在流化狀態(tài)，因干燥不充分而粘于壁上或底部。如提高*微囊的供液速度，雖對其吸濕性的影響不大，但會使其分散率明顯下降””。造成霧滴粒徑過大，干燥不充分而粘壁。影響噴霧干燥的因素很多，除上述因素外，還存在藥液溫度、負(fù)壓大小、負(fù)壓的穩(wěn)定性等因素，因此在實(shí)際操作中應(yīng)綜合考慮上述影響因素對噴霧干燥工藝的影響。 

3 有機(jī)溶劑噴霧干燥機(jī)關(guān)于中藥提取物防粘壁的思考  輔料可通過改善物料的吸濕性、提高物料的軟化點(diǎn)、增強(qiáng)提取液的流動性、改善提取液的霧化效果、對易吸濕造成粘壁的成分進(jìn)行包裹等，以發(fā)揮其防粘壁作用。因輔料在改善中藥提取物性質(zhì)方面起著重要作用，所以有機(jī)溶劑噴霧干燥機(jī)噴霧干燥過程中的應(yīng)用顯得尤為重要。對于復(fù)方提取物而言，因其理化性質(zhì)較為復(fù)雜，通過單一輔料進(jìn)行改性所發(fā)揮的作用有限．而通過多種輔料聯(lián)合應(yīng)用，則可從多方面共同發(fā)揮防粘壁作用。對有機(jī)溶劑噴霧干燥機(jī)，適當(dāng)提高進(jìn)風(fēng)El的溫度，可減少粘壁現(xiàn)象的發(fā)生。噴霧干燥所用壓縮空氣的壓力應(yīng)保持恒定，壓力的波動會產(chǎn)生嚴(yán)重的粘壁現(xiàn)象。噴嘴進(jìn)料速度和噴嘴的壓縮空氣量應(yīng)匹配，正常操作中應(yīng)隨時(shí)檢查噴嘴霧化效果，以減少粘壁的發(fā)生。但通過調(diào)整參數(shù)來發(fā)揮粘壁作用比輔料的應(yīng)用所發(fā)揮的作用要小，參數(shù)的調(diào)整范圍也很有限。鑒于中藥成分的復(fù)雜性，在整個(gè)噴霧干燥工藝的研究過程中，要充分分析和了解物料的性質(zhì)，通過輔料的應(yīng)用和噴霧干燥設(shè)備參數(shù)的調(diào)整，總結(jié)防粘壁規(guī)律，以解決中藥粘壁問題，zui終得到科學(xué)、合理、可行的噴霧干燥工藝。

?2 Effect of device parameters on traditional Chinese medicine organic solvent spray dryer wall sticking of spray drying is fluidized drying technology for a better method of liquid material, the process is the use of liquid atomizer to certain concentration of spraying droplets, heat exchange of droplets in the solvent evaporates quickly in the dry the medium for powdery and granular products. Because of the different physical and chemical properties of Chinese medicine, the mass transfer and heat transfer rate also differ greatly, resulting in different degrees of adhesion to the wall. On the premise of fully grasping the physicochemical properties of the extract of traditional Chinese medicine, the conditions of the adhesive wall can be improved by adjusting the parameters of the spray drying equipment.
2.1 the nozzle of the organic solvent spray dryer is installed in the spray drying process, increasing the dispersion of the material, and accelerating the heat transfer and mass transfer process. The installation of the nozzle is very important for the spray equipment. When the droplets from the nozzle, its shape is a compressed air heart with tapered film, droplet should be distributed evenly in the spray cone; the spray cone is symmetrical, if not concentric will deviate from the center line, thereby affecting the atomization effect, cause droplet diameter and liquid line will be serious, caused by wall sticking phenomenon. Therefore, the concentricity must be guaranteed in the process of use.
2.2 the control of the quantity of hot air volume is reflected in the water content of the dry material, which has a direct relationship with the wall of the sticky wall. Because the spray drying process is operated under the micro negative pressure, whether the droplet can reach the drying effect and remove the dry material depends on the amount of hot air. At the same time, the diameter of the droplet can be adjusted by the amount of hot air. As the amount of hot air increases, the droplet diameter decreases, the drying speed increases, and the wall adhesion may be relatively reduced. However, if the gas flow rate is too large, the moisture absorption of the powder will be enhanced, and the sticking phenomenon will occur in the spray process. If the gas flow rate is too small, the fog diameter will be too large and the drying will not be enough.
2.3 the inlet temperature of the air inlet temperature of the organic solvent spray dryer is also the main factor affecting the wall adhesion. Guo Jianbo research shows that if the air heater is fully opened when opening the device, it will cause the outlet temperature to rise rapidly, and the actual tower temperature is not balanced up. The temperature is uneven. At this time, the spray will easily produce sticky walls. If the temperature is too high, it will cause damage to the effective components of Chinese medicine or change the properties of some components; the temperature is too low and can not be fully dried, and the phenomenon of wall sticking occurs. In the suitable range, the higher the air inlet temperature is, the faster the solvent evaporation, the viscosity of the wall is reduced. If the extract of Chinese medicine contains more viscous components, the inlet air temperature and outlet temperature should be reduced appropriay, so that the spray drying can be carried out smoothly, because the carbohydrate components are increased after the high heat viscosity, resulting in sticky wall phenomenon. Decreasing the temperature appropriay can reduce the sticky condition.
2.4 the velocity of feeding liquid supply is also closely related to the phenomenon of wall sticking. When the other conditions are not changed, the speed of the feed is accelerated, which causes the droplets not to be in the flow state and stick to the wall or bottom because of the insufficient drying. as