Why Is Powder Flow Important In Pharmaceutical Manufacturing?

1.What isDefinition of Powder Flow?

Powder Flow - Sourced: Perkchops

As is well known, liquids can flow, did you know that powders can also flow? You may wonder what powder flow is? Powder flow refers to the physical properties exhibited by powder during the flow process, specifically manifested as the displacement ability of the powder under the action of gravity. To be honest, the reason why powder flows is essentially due to the imbalance of forces on particles in the powder.

Power flow is directly related to the smooth process of powder transportation, mixing, filling, and pressing. In short, good flowability means that the powder can be evenly and quickly distributed, reducing clogging, thereby improving production efficiency, and ensuring product quality.

2.Why Is Powder Flow Important In Pharmaceutical Manufacturing?

In the pharmaceutical production process, powder is the main raw material and can be used to produce capsules, tablets, etc. Therefore, powder flow is crucial in the pharmaceutical production process. Do you know the importance of that?

Controllingthe quality of medicine

Controlling the Quality of Medicine - Sourced: Technology Networks

The powder flow is related to the quality of the final pharmaceutical product, and the capsules we take are made by mixing many powdered drugs. If the powder flow is poor, these drugs cannot be mixed evenly, which affects the final efficacy.

Optimizing production process

Ensuring Production Process - Sourced: Wolters Kluwer

As we all know, many machines, such as capsule filling machine use power to produce pharmaceutical products. If the powder flow is poor, it can affect the operation of the machine, such as machine jamming.

If the powder flow is good, it is easier to achieve uniform mixing, which facilitates the entire drug production process and does not delay work due to blockage, greatly improving work efficiency.

Ensuring production safety

Ensuring Production Safety - Sourced: IFPMA

Powder with poor flow may generate static electricity during processing, posing a safety hazard. Improving powder flow can reduce the risk of static electricity generation and enhance the safety of the production environment.

In addition, powders with good fluidity are more stable during storage and transportation, reducing the possibility of leakage and environmental pollution.

3.What Factors Will Affect Powder Flow?

Are you curious about the factors that affect the powder flow? Next, I will take you to understand.

Temperature

Temperature - Sourced: Science4Fun

As the temperature increases, the powder flow shows a trend of first increasing and then decreasing. This is because at low temperatures, the density of powder particles increases with increasing temperature; When the temperature is too high, the adhesion of the powder increases.

Humidity

The humidity of powder refers to the amount of water, also the moisture content in the powder. When the moisture content of the powder is very low, water is adsorbed on its surface, and this adsorbed water has little effect on the powder flow.

As the moisture increases, a thin film of water is formed around the adsorbed water. At this time, relative movement between particles is not easy to occur, which limits the overall flow of particles. When the moisture increases beyond the maximum molecular bound water, the powder flow deteriorates, and even loses its flowability.

The size of particle

The Size of Particle - Sourced: Swift River

The smaller the particle size of power, the larger the specific surface area, the stronger the electrostatic and molecular attraction, and the greater the possibility of adsorption, aggregation, and bonding between particles, which will affect the flow characteristics of the powder.

Shape

Even if the particle size of the powder is equal, different forms of powder have different flowability. Spherical particles have the best flowability because they have the smallest contact area; There are a large number of shear forces and planar contact points between irregular particles on the surface of sheet-like or branched particles, resulting in poor flowability.

4.What Are the Patterns of Powder Flow?

Do you know what are the patterns of powder flow? There are two patterns of powder flow in a silo.

Funnel Flow VS Mass Flow - Sourced: Chemical Engineering

Funnel flow

Funnel flow, as the name suggests, is a form in which powder flows out of a silo like material in a funnel under the action of gravity. In this form, materials flow by overcoming internal friction rather than sliding down the angled walls of the silo. In this form, some materials are flowing while others remain stationary in the silo.

Mass flow

During the unloading process, all the materials in the hopper are in a uniform downward motion state, and this flow state becomes the mass flow. There are no dead corners in the overall flow chamber, and the flow is uniform and smooth, which can re mix materials with separated particle sizes. The overall flow needs to increase the height of the hopper and increase the wear of the hopper wall.

In short, funnel flow is a flow state that hinders production, while mass flow is the reasonable result of proper hopper design.

5.What Methods Can Be Used to Measure Powder Flow?

You must know the importance of powder flow, then do you know any methods to measure powder flow?

Angle of repose method

Angle of Repose Method - Sourced: Springer Link

This method is one of the most intuitive ways to measure powder flow. By using this method, you should drop a certain amount of powder from a certain height and stack it on a horizontal plane to form a cone. The angle between the generatrix of the cone and the horizontal plane is the angle of repose. The smaller the angle of repose, the better the powder flow.

Carr index method

The Carr index method is a comprehensive evaluation of powder flow, which measures the loose density and tap density of the powder under different vibration conditions. It can calculate the ratio of the two (Carr index) to evaluate the powder flow. The smaller the Carr index, the easier it is for the powder to compact and have better flow under vibration.

Shear testing method

Shear Testing Method - Sourced: Freeman Technology

The shear test method evaluates the power flow by simulating the shear force experienced by the powder during the flow process and measuring its flow resistance. This method is particularly suitable for situations that require high-precision evaluation of powder flow, such as powder mixing and compression processes in the pharmaceutical industry.

Measure the flow rate

Continuous powder flow should be maintained during measurement, as even power with good flow can experience pulse flow, and changes in outflow velocity can be observed when the container is emptied.

Several important parameters to be considered in the measurement include: 1. the diameter and shape of the small hole; 2. Types of container materials (metal, glass, plastic); 3. The diameter and height of the powder bed in the container.

6.What Equipment Can be Usedin the Measurement of Powder Flow?

With the continuous development of science and technology, many equipment to test power flow have been invented. Next, I will introduce three common equipment.

Angle of repose tester

Angle of Repose Tester - Sourced: KARG Industrietechnik

One of the methods we mentioned earlier for detecting powder flowability is the detection method. The angle of repose tester use this method to characterize the powder flow. By measuring the angle of repose, the friction performance and powder flow can be understood, providing important references for optimizing production processes and guiding equipment selection.

Hall flowmeter

Hall Flowmeter - Sourced: Bettersize

A Hall flowmeter is an instrument used to measure the flow of powder or granular materials. This instrument utilizes the Hall effect to determine the velocity of powder flow by measuring the magnetic field changes on the sensor. Gnerally, the Hall flowmeters typically consist of a controller and a sensor.

Power flow tester

Powder Flow Tester - Sourced: AMETEK Brookfield Asia

With measurement technologies such as laser velocimetry and weighing sensors, this powder flow tester can monitor and record the flow rate and particle size of powders in real time. Users can fully understand the flow and particle size distribution of the powder.

7.What Is the Common Problems and Solution for Powder Flow?

Powder flow is crucial for the quality of the final product, but there are often some issues with powder flow. Do you know how to solve these problems?

Low flow

Low Flow - Sourced: Granutools

The low flow of the powder will not directly affect the operation of the machine, but it will affect the subsequent production process. Therefore, a larger feeder can be replaced or the reducer on the driver can be replaced to speed up the process.

No flow

Powder not flowing may cause machine shutdown. To address this issue, a mixer can be used to stir the powder before feeding, or a vibrator can be added to the hopper to help the powder flow.

Powder clumping/caking

Powder Clumping - Sourced: Atlas Bar

Powder clumping is difficult to mix with materials and can cause blockages, so it is necessary to check whether the powder has high humidity or poor quality. Therefore, the storage location of the powder can be changed or the powder material can be replaced.

8.How toOptimize Humidity for Powder Flow?

We have already discussed in the previous text that powder humidity has an impact on powder flow. As high humidity can cause clumping and affect flowability, while low humidity can lead to powder brittleness or deformation, how to optimize humidity for powder flow has become a problem waiting to be solved.

Storage environment for powder

Storage Environment - Sourced: Texas Farm

The storage environment for powders should maintain a relatively low humidity, usually between 30% and 50%. Excessive or insufficient humidity can have an impact on the powder flow.

In addition, establishing a scientifically reasonable ventilation system to ensure circulating ventilation in the powder warehouse. Regularly checking the temperature and humidity inside the powder warehouse, and adjust the working status of ventilation, cooling, heating and other equipment based on the test results.

If the power is exposure to sunlight, the powder will absorb moisture. So it is necessary to store the powder in a dark environment.

Protection of powder processing equipment

In the process of powder processing, a drying system can be added to remove humid air, for example, a dryer or drying oven can be installed to control the humidity of the powder.

In addition, you should ensure that the processing equipment has good sealing performance and reduces the entry of humid external air. Once other liquids or impurities enter, they will affect the properties of the powder, thereby affecting its flowability.

9.What Will Powder Flow Influence on thePharmaceutical Product?

Do you know what impacts the powder flow has on the final pharmaceutical product? Let’s look them together.

Affecting the uniformity of pharmaceutical product mixing

Uniformity of Pharmaceutical Product Mixing - Sourced: ConsumerLab.com

The particle size and density of the powder determine the tendency of the material to separate or mix during the mixing process. If the mixed materials have similar particle size and density, the tendency for separation will decrease and an equilibrium state will be reached between mixing and separation.

The powder flow directly affects the uniformity of mixing. If the flow is too poor, it is easy to adhere and clump during mixing, making it difficult to mix evenly; However, if the flow is too good, it is not easy to mix evenly. If the flow is too good, it is easy to separate from other powders. Even if the mixture is evenly mixed, it is easy to cause delamination during discharge, transportation, powder loading, and other processes.

Affecting the dosage of the product

Affecting the Dosage of the Product - Sourced: Pngtree

If the particle size distribution of the powder is wide, there may be differences in bulk density, which can affect the difference in dosage. If the particle size of the powder is too small or the self weight of the particles is small, it will affect the flowability of the material.

Affecting drug disintegration

Drug Disintegration - Sourced: ZS

Once the drug progresses, it will be disintegrated, released, and ultimately absorbed in the body. Disintegration is the primary condition for the drug to exert its effect. If the humidity of the powder is high, it will be difficult for water to penetrate into the tablet, and the tablet will be difficult to disintegrate.

10.How to Improve Powder Flow in Pharmaceutical Manufacturing?

We understand the importance of powder flow in pharmaceutical production, so we all want to obtain powders with good flow. Do you know how to improve powder flow in pharmaceutical production?

Controlling the particle size of the powder

Particle Size of the Powder - Sourced: Contract Laboratory Outsource

The particle size is one of the important factors affecting the powder flow. If the particle size is too large or too small, it will cause poor powder flow. Increasing particle size and pelletize adhesive powder particles to reduce the number of contact points between particles, thereby lowering their adhesion and cohesion

Choosing appropriate additives

Choosing Appropriate Additives - Sourced: by ALPA Powder

When adding 0.5% to 2% talc powder, micro powder silica gel and other flow aids to the powder, the powder flow can be greatly improved. This is mainly because micro powder particles fill the rough surface of the powder particles to form a smooth surface, reducing resistance and electrostatic forces. However, excessive flow aids actually increase resistance.

Adopting vibration screening technology

To tell the truth, many machines are equipped with vibration screening technology to screen powders, remove unnecessary particles and impurities, thereby improving the flowability of powders. This method is suitable for large-scale powder processing and can improve production efficiency and product quality.

Adopting ultrasonic treatment technology

Adopting Ultrasonic Treatment Technology - Sourced: Sinaptec

Ultrasonic treatment technology uses ultrasonic waves to treat powders, breaking the electrostatic force and adsorption force on the surface of the powder, thereby improving the powder flow. This method is suitable for small batch powder processing and can improve the quality and flowability of the product.

Conclusion

In the pharmaceutical industry, the power flow is directly related to the smooth operation of production lines. By optimizing powder flow, enterprises can improve production efficiency, product quality, enhance production safety, and effectively control costs, thereby occupying a favorable position in fierce market competition. This article takes you to understand the importance of powder flow in pharmaceutical production, as well as methods and instruments for measuring powder flow. If you have any further questions about powder flow, please feel free to contact AIPAK at any time.