YC-018A Pilot Scale Spray Dryer

Pilot Scale Spray Dryer : The Complete Buying Guide

In the laboratory, it is possible that you may need to test more samples. For example, one day, if you have 20L of materials or more to be dried, laboratory spray dryer cannot handle it in a day. At this time, you need YC-018A pilot scale spray dryer.

But there are several big problems in the general pilot scale spray dryer.

1) Large size: usually 3-5 square meters, only one general pilot scale spray dryer can be put in a general laboratory considering the operating space, occupying too large floor area.

2) High noise: the general pilot scale spray dryer has high noise (90DB or above), very unsuitable for use in laboratory.

3) High power: the general pilot scale spray dryer has high power consumption (15KW or above).

Pilotech YC-018A pilot scale spray dryer perfectly solves the three problems: 1) Small size, 1050*900*1750MM, occupies only 1 square meter; 2) Low power, only uses  5.5KW; 3) Low noise, 60DB or below. Pilotech YC-018A pilot scale spray dryer has little impact on the environment, and is especially suitable for use in the laboratory.

There is still a big problem in the general pilot scale spray dryer equipment. You cannot get any powder samples if you just want to test a small amount of materials. 2000ML of sample is needed at least. Pilotech YC-018A pilot scale spray dryer can carry out the experiment even if only 100ML of sample is to be tested. You do not need to buy another laboratory spray dryer machine.

The recovery rate is also important for the pilot scale spray dryer. The traditional pilot scale spray dryer has a lower recovery rate, less than 60%, causing a great loss. If the sample is expensive, the loss will be even greater. The maximum recovery rate of Pilotech YC-018A pilot scale spray dryer can reach 92%.

Pilotech YC-018A pilot scale spray has a relatively wide temperature range. The maximum air inlet temperature is 350 ° C, suitable for some samples requiring high temperature for drying; and the minimum air inlet temperature can reach 110° C. Some sugar-containing materials and heat-sensitive materials can be dried well under such low air inlet temperature, and there will be no denaturation and wall sticking problems.

If you’re looking for lab & pilot scale spray dryer supplier, then you’re in the right place, contact us for a quick quote now.

Pilot Scale Spray Dryer: The Ultimate FAQs Guide

In this guide, you will find all information about pilot scale spray dryer machine.

It covers all information, including classification criteria, working principle, specifications, applications, nozzle types and properties of the final product, among other vital aspects.

Keep reading to learn more.

What is Pilot Scale Spray Dryer?

Pilot scale spray dryer are suitable for small scale testing, research and development and small scale powders production.

They are ideal for producing testing samples, feed formulation studies, and establishing optimum drying conditions.

However, you cannot utilize the drying equipment for developing required particle size or physical features achievable with large scale spray dryers.

Pilot scales spray dryer

Which are the Types of Pilot Scale Spray Dryer?

There exist various types of pilot scale spray drying machines including:

· Co-current Flow Spray Dryer

Here, the system directs the feedstock spray into heated gas flowing into the spray drying equipment.

Both the spray and heated air go through the drying chamber in similar direction.

Co-current pilot scale spray dryer is ideal for thermo-labile products.

This is due to the fact that contact between drying gas and liquid droplets happen at maximal moisture content of droplets.

Spray vaporization is rapid, which quickly reduces the drying air temperature.

There is negligible heat degradation since the temperature of droplet is low throughout the evaporation time.

After attaining the target moisture content level, the particle temperature does not rise significantly.

The negligible increase in temperature is due to cooler surrounding air.

Often, co-current pilot scale spray dryer is efficient in drying dairy and heat-sensitive foodstuffs.

· Counter-current Flow Spray Dryer

With this pilot scale spray dryer design, the drying air and spray flow in at opposing sides of dryer.

It has the atomizer at the upper part while the hot air enters at the base.

This type of spray dryer ensures greater energy efficiency and faster evaporation in comparison to co-current type.

Since driest powder particles interact with hottest gas, counter-current pilot scale spray dryer is not appropriate for heat-sensitive materials.

They usually employ spray nozzles to atomize the feed since it is possible to direct spray energy against movement of air.

· Mixed Flow Spray Dryer

Pilot scale spray dryers of this kind blend both counter-current and co-current flow.

In the drying equipment, you will find atomizer at the base while drying air flows in at the upper part.

Similar to counter-current version, mixed flow spray drying machine subjects driest powders to hottest drying gas.

Therefore, this design of pilot scale spray dryer is not appropriate for heat-sensitive products.

· Open Cycle Spray Drying Machine

The system sucks in atmospheric air, heats it, conveys across drying compartment, and eventually exhaust to the environment.

This design of pilot scale spray dryer is the most common.

· Closed Cycle Spray Dryer

Closed cycle spray dryer reuses the gas for drying that might be an inert gas or air.

This type of spray drying plant is best if:

• Feedcomprise of solid materials blended with inflammable organic solvents.
• You require total solvent recovery
• The materials are toxic
• There is ban on pollution because of odor, particulate emissions or vapor.
• There is need to eliminate risks of explosion
• Oxidation during spray drying will degrade the powder.

· Semi-closed Cycle Spray Dryer

This is a blend of closed and open cycle spray drying machines and it is not airtight.

There exist several varieties of this design, though “self-inertizing” or “direct heated” system being the most essential.

In self-inertizing type, it uses a direct-fired heater, and it restricts air flowing into system to that needed for combustion.

The spray dryer bleeds out of the system an air amount equivalent to combustion air.

The bleeding takes place at the opposite side of the drying process.

Also, the system recycles the drying gas through the pilot scale spray drying plant.

The gas features exceptionally low content of oxygen.

Therefore, you can use it for products that you should not expose to oxygen because of degradation or explosive hazard.

There is another version of semi-closed cycle spray dryer that features indirect air heater.

· Single Stage Spray Dryer

The spray drying machine reduces the moisture content to target value in single pass across the equipment.

Most pilot scale spray drying equipment come as single stage designs.

· Two Stage Spray Drying plant

In this pilot scale spray dryer type, the product exiting the drying chamber has higher moisture content than end product.

After exiting the chamber, the spray drying equipment further reduces the moisture content in second stage.

The second phase drying might take place in vibrating bed drying equipment or fluidized bed dryer.

Besides, the spray dryer design enables use of decreased temperature, making it ideal for heat-sensitive materials.

· Horizontal Spray Dryer

Horizontal dryer features a rectangular box drying chamber having a V-shaped or flat base.

Nozzles of box spray dryers usually spray horizontally and the dried particles fall to the bottom.

A screw conveyor or sweep conveyor moves the dried powder to a bagging segment.

This type of pilot scale spray dryer is normally small and feature comparatively short particle dwell time.

For that matter, it always uses low flow spray nozzles.

· Vertical Spray Dryer

Also referred to as tower pilot scale spray dryer, it features a tall cylinder having cone-shaped base as drying chamber.

It can have spray nozzles located at the base (mixed/counter-current), or upper part (co-current) of the drying chamber.

Moreover, you can have the heated drying air inlets at the chamber’s side, base, or top.

Vertical spray drying machines are often big, and feature comparatively long dwell time.

Therefore, they normally use higher flow spray nozzles, which create comparatively large particles.

Which are the Key Components of Pilot Scale Spray Dryer?

There exist several types of pilot scale spray dryers, each with differing properties for fulfilling various spray drying requirements.

The primary parts of a small scale spray dryer consist of:

Components of spray dryer

• Process control systems
• Material Feeder
• Spray nozzles or atomizer
• Air Disperser or air heater
• Drying tower chamber
• powder recovery systems

What is the Difference Between Rotary Atomizer and Pressure Atomizer of Pilot Scale Spray Dryer?

Centrifugal or rotating atomizers feed liquid formulation at the middle of swiftly rotating disks.

The disks may feature vanes to help in directing the flow.

The system ejects a sheet of fluid from the margin and disintegrates into droplets.

This type of atomizer is specifically ideal for feeds consisting of entrained solids.

Centrifugal atomizers generate more regular sizes of particles in comparison to pressure spray nozzles.

Nevertheless, rotary atomizers might be more costly compared to other options.

Conversely, pressure nozzles feature small orifices via which the pilot scale dryer forces fed streams.

On leaving the nozzles, the feedstock disintegrates into droplets.

They are less costly compared to rotating disk atomizers.

Nonetheless, they are prone to increasing back pressure, plug and disorganizing flow pattern of particles.

What are the Factors to Consider when Choosing Pilot Scale Spray Dryer?

You must consider several factors when choosing the best pilot scale spray dryer for your application:

· Type of Atomizer

The atomizer type used in the pilot scale spray dryer dictates particle size and product moisture.

For instance, a rotary atomizer will provide wider particle size distribution while spray nozzles offer narrower distribution.

Choosing the correct atomizer can as well influence the color of your products.

This is because of link between size of particle and color.

· Nozzle Configuration

Moreover, another consideration is whether you will use the nozzle in counter-current flow or co-current flow configuration.

This impacts the dwell time within the drying chamber and size of powder particles.

· Type of Spray Dryer

The type of pilot scale spray dryer also matters during selection.

For example, you will achieve product specifications when using tall form spray dryer due to its increased surface area.

Moreover, the design of spray drying chamber base also impacts the drying operation.

Besides, configuration of dryer as well influences powder yield and cleaning duration leading to cost implications.

· Ease of Operation and Maintenance

The best pilot scale spray dryer should be one that ensure ease of operation and maintenance.

Furthermore, it needs to be easy to wash and sterilize.

If possible, the spray drying equipment should feature a Clean-in-Place system to avoid unnecessary disassembly of the system.

· Contact Parts Material

The materials used to make the contact components of the small scale spray dryer must be corrosion-resistant and non-toxic.

Additionally, they should not feature easy-to-shed particulate materials, fibers and coatings.

· Internal Wall

Spray dryer inner wall should be polished and flat, and lacking concave structure. Also, make sure that it has all corners rounded.

· Safety

Ensure that the spray dryer you choose runs steadily, and sewage discharge, dust and noise must conform to relevant regulations.

Moreover, the pilot scale spray dryer must be safe to work run.

It should adhere to all necessary safety regulations, consisting of mechanical, electrical and gas requirements.

· Airtightness

The best small scale spray drying machine should feature good airtightness.

This is in addition to all coolants and lubricants not contacting products and packaging.

· Efficiency and Cost

Another important to consider is the cost of the pilot scale spray dryer.

You should factor in both the initial cost of buying the machine and operation cost throughout its life.

How Do you Maintain Nozzles of Pilot Scale Spray Dryer?

Nozzle for spray dryer

Spray nozzles of pilot scale spray dryers typically function at high pressures.

Due to the abrasiveness and high velocities of feedstock via the nozzles, it wears the internal components of nozzles.

There is deterioration in pilot scale spray drying machine performance as components of the nozzles wear.

The common signs of worn spray nozzles include increased droplet size, increased flow rate, and deterioration of spray pattern consistency.

Therefore, here are some of the ways of maintaining spray nozzles of pilot scale spray dryer:

· Swirl

Three main swirl components will display first noticeable signs of wear, including:

• Narrow “tongue” forming one section of the inlet.
• Corner separating the wall and base of the chamber
• Chamber base itself

Among the 3 parts, the tongue will have greatest influence on pattern of spray.

For that matter, you should replace the swirl immediately the tongue exhibits substantial wear signs.

· Orifice Disk

In most situations, you will observe uniform wearing of the orifice and the diameter of the hole will increase in size.

This in turn leads to increase in flow rate.

Therefore, it is advisable to replace the orifice disks if the rate of flow increases by 5 percent.

This is equal to 2.5 percent increase in hole diameter.

· Seals

Leaking spray nozzles of a pilot scale spray dryer can result in serious issues, including explosions, fires and ruined products.

Due to this fact, it is important to make sure there is no leaking nozzles during operation.

Majority of nozzles employ o-ring seals.

You need to replace the o-rings each time you disassemble the spray nozzle.

This due to the high temperatures and operating pressures of drying chamber.

Moreover, apply approved lubricating oil on all o-rings.

· Disassembly and Cleaning

Often, you can employ dilute caustic solution (1 to 2 percent NaOH) to clean the spray nozzles.

When spray drying products like whey and cheese, you must clean the nozzles immediately after shutdown.

Cleaning right after shutdown prevent sticking together of the nozzle parts.

However, some incorporate clean-in-place (CIP) systems to avoid disassembly of the spray nozzles.

After removing the swirl and orifice disk for cleaning, you should install spare carrier to minimize flow during CIP.

What are the Benefits of Pilot Scale Spray Dryer?

Pilot scale spray dryer allows you to manufacture powders having specific moisture content and particle size.

It does this irrespective of the dryer capacity or product heat sensitivity.

The versatility makes it the drying equipment of choice for most industrial drying applications.

Here are some the advantages of pilot scale spray dryer:

• Used in a variety of applications including dairy and food product drying to aseptic pharmaceutical processing.
• Occupies less space due to its small and compact design.
• Produces less noise making it environmentally friendly.
• Consistent powder quality throughout the whole pilot scale spray dryer run.
• Continuous operation and compatible with total automatic control.
• Availability of several versions of spray drying machines to fulfil differing product specifications.
• Can process both heat-sensitive and heat-resistant products.
• You can process a great variety of feedstock from toxic, flammable, explosive, corrosive or abrasive.
• Feedstock may be in melt, gel, slurry, suspension, solution, gel, or paste form.
• Allows you to control product density.
• Enables production of almost spherical particles.
• Reduced corrosion issues since the raw material doesn’t come into contact with metal surfaces till dried.

What is the Function of Atomizer in Pilot Scale Spray Dryer?

Pilot spray dryer structure

The role of the atomizer of pilot scale spray dryer include:

• Meter flow of hot air into the drying chamber
• Produce the desired size of the liquid droplets
• Distribute the liquid droplets evenly in the drying chamber

Here are the factors to consider during the selection of atomizer:

• Feedstock
• Desired powder properties
• Capacity and type of pilot scale spray drying machine
• Capacity of the atomizer

What are the Disadvantages of Using Rotary Atomizer in Pilot Scale Spray dryer?

Here are some of the main drawbacks of rotary atomizers:

• High capital cost
• Generate large amounts of fine powders, which can cause pollution control issues.
• Very costly to maintain
• You cannot use in horizontal pilot scale spray dryers
• Challenging to utilize with excessively viscous materials.

Due to the issues and costs related to rotary atomizers, it is best to replace it with spray nozzles.

Which are the Main Powder Properties Monitored When Drying Using Pilot Scale Spray Dryer?

Pilot scale spray dryers help in the conversion of liquid feedstock to powder particles.

Similar to liquid feedstock, there are crucial properties of powder that you must monitor during the process of spray drying:

· Powder Shape

Most types of spray dryers create spherical powder particles, whilst there are some that produce non-spherical powders.

Moreover, the spray drying machine can as well develop solid or hollow powders.

Usually you use aspect ratio to characterize non-spherical powder particles.

Aspect ratio of particle refers to longest measurement to shortest measurement ratio.

· Size of Powder

It is crucial knowing the dissimilarity between particle and droplet size since the 2 are not always similar.

Relation between average size of dried particles and liquid droplets is not constant.

The technique utilized for measuring dried powder particles sizes consist of sieving, microscopy, laser, and sedimentation methods.

Pressure nozzles are capable of producing particle sizes spanning from 20 to 600 microns.

Size of particle produced by pilot scale spray dryer depends on properties of feedstock, type of nozzle and conditions of operating.

Two-fluid spray nozzles typically generate particles sizes spanning from 10-200 microns and greater.

· Size Distribution

Final dried powder exhibits tighter size distribution in comparison to that of atomized fluid particles.

Using rotary atomizers lead to production of particles having more regular particle sizes than pressure atomizers.

· Bulk Density

This refers to weight of dehydrated particles/specific volume.

It is vital parameter in majority of pilot scale spray dryers because it influences size of containers.

You must monitor the powder bulk density throughout the operation of small scale spray dryer.

What is the Importance of Agglomeration in Pilot Scale Spray Dryer?

Sometimes you may want to produce particles larger compared to those developed using single stage pilot scale spray dryer.

In such instance, you can employ agglomeration, which refers to particles enlargement process by making them adhere to one another.

Agglomerated powder particles might exhibit higher bulk density, enhanced flow properties, enhanced solubility and reduced dust.

Occasionally, you can use two stage spray dryer to agglomerate material particles.

Because you have sticky particles leaving the initial drying stage, they will adhere together in the second drying stage.

Some types of pilot scale spray dryers sprinkle first stage wet particles with extra feed during second stage.

The fresh feed helps in softening the particles surface and enables them to enlarge.

You refer to this process as re-wetting agglomeration or instantizing.

Most spray dryer processes comprise of fine particles recycling.

The system injects back into spray area the fines collected by separation equipment.

Returning fines encourage agglomeration process.

This results in development of coarser, more free-flowing and dustless powder.

Which are the Pharmaceutical Products you can Spray Dry Using Pilot Scale Spray Dryer?

Pilot scale spray drying machine

Most biochemical and pharmaceutical products require spray drying.

The capacity of spray drying needed for these products vary from low to high.

Pilot scale spray drying machines used for pharmaceutical applications comprise of: aseptic closed- and open-cycle systems.

Most of the dryers use either pressure nozzle or two-fluid atomizers:

Here are some of the pharmaceutical products you can produce using pilot scale spray dryer:

• Algae
• Penicillin
• Antibiotics
• Vaccines
• Streptomycin
• Dextran Drugs
• Spores
• Amino acids
• Sulphatiazole
• Pharmaceutical gums
• Enzymes
• Tabletting constituents
• Hormones
• Vitamins
• Sera

What is Aseptic Pilot Scale Spray Dryer?

This describes a kind of spray drying equipment engineered and sustained to offer sterile set-up.

The environment allows development of products lacking disease-causing and putrefying microbes.

In most case, this pilot scale spray dryer type finds application in production of pharmaceutical and food products.

How Do you Measure Droplet Size in Pilot Scale Spray Dryer?

The common unit of measuring atomized liquid droplet diameter is micrometers (microns).

However, spray nozzles give a droplet sizes distribution instead of equal size diameter.

Therefore, you will often have droplet size referenced in terms of Sauter Mean Diameter (D32) or Volume Median Diameter (DV0.5).

What is the Role of Pilot Scale Spray Dryer Absorber?

Spray dryer absorber refers to systems that utilize reagent feedstock for absorption and reaction with harmful gases, like HCL and SO2.

The end product is non-toxic powders.

It includes atomization of an appropriate absorbent inside a chamber where there is flow of flue gas.

Absorbents used consist of sodium carbonate solutions and limestone and lime slurries.

The liquid droplets closely interact with the harmful flue gas components.

The system forms and recovers a dry product at the bottom of the pilot scale spray dryer absorber.

To remove fines, the scrubbed gas goes through an electrostatic precipitator or bag house.

SDAs use both two-fluid nozzles and rotary atomizers.

The common application of spray dryer absorbers is in waste incinerator plants.

What is the Difference Between Volume Median Diameter (DV50) and Sauter Mean Diameter?

Sauter mean diameter, commonly denoted as D32refers to particle diameter whose mass to surface area ratio matches that of entire product.

Conversely, Volume median diameter (DV50)refers to particle diameter that splits the mass/volume of the product into 2 equal halves.

One half consists of particles or droplets having diameters lower than the DV05.

The other sample half comprise of particles having diameters bigger than DV05.

Spray dryer with air compressor

What is the meaning of Dwell Time in Pilot Scale Spray Dryer?

Also referred to as residence time or retention time.

It refers to the time duration spray droplets takes to travel across drying chamber prior to deposition as dried powder.

What is the Difference Between Particle Size and Particle Density of Pilot Scale Spray Dryer?

Particle density defines individual particles density; as differentiated from bulk density.

On the other hand, in spherical dry powder, particle size refers to the particle diameter.

In the case of non-spherical powders, size of particles denotes the mean length between the short and long particle edges.

You determine particle size by measuring the distance through center of gravity of the non-spherical particles.

What is the Function of Paste Nozzle in Pilot Scale Spray Drying machine?

This represents a nozzle type utilized in spray drying of pastes.

What is Prilling and Puffing in Pilot Scale Spray Dryer?

Prilling describes the production of crystals or pellets due to the cooling effect of upward moving cooling air within drying chamber.

The spray droplets form the crystals/pellets as they fall to the chamber base.

The feedstock melting temperatures are beyond the cooling air temperature.

Moreover, they are always above the ambient air temperature.

Conversely, puffing refers to particle enlargement. It is due to expansion of vapor formed inside the droplet.

The reason for expansion is increase in temperature of the droplet.

Can you Customize Pilot Scale Spray Dryer?

Yes, you can customize the design and features of pilot scale spray dryer to meet your specific operation requirements.

You can choose the construction materials, atomizer type, drying chamber height, locations and type of powder collection system, and interior finishes.

Which are the Different Ways of Powder Collection in Pilot Scale Spray Dryer?

After completing the spray drying process, the pilot spry dryer must separate the product particles and the drying gas.

The system achieves primary separation by the dried powder simply dropping to the drying chamber base.

A small particles portion stay fused with the heated gas, which you must recover within separation equipment.

There are three main techniques of final powder collection including electrostatic precipitators, bag filters and cyclones.

Typically, the pilot scale spray dryer directs flow of air from the chamber base either to cyclones or auxiliary dryer.

In most cases, fluidized bed dryer follow the spray dryer to complete the particles drying process.

Moreover, the dry particles and air go via a cyclone, where majority of the powders fall for eventual collection.

There is more collection of powder products as exhaust travels across bag filters.

Spray dryer system

How do you Specify Pilot Scale Spray Dryer?

These are the key specifications of pilot scale spray dryer that you must look for:

• Power
• Voltage
• Evaporating Capacity
• Inlet temperature
• Outlet Temperature
• Airflow
• Temperature precision
• Nozzle type
• Heater power
• Nozzle jet
• Possible range of particle size
• Sample feed
• Operation mode
• Spray chamber material
• Minimum sample volume
• Receiving tank material
• Cyclone separator material
• Body material
• Gas type
• cyclone/cylinder seal
• Display
• Dimensions
• Thermal protection
• Weight
• Inert loop (organic solvents)

Which are the Applications of Pilot Scale Spray Drying machine?

Here are the common uses of pilot scale spray drying machines:

1. Pharmaceutical industries to dry vaccines, enzymes, blood products, among other applications
2. Chemical industries for example in processing of amino acids, catalysts, PVC emulsion type, and phenol-formaldehyde resin etc.
3. Ceramic industries for example production of kaolin, aluminum oxide, iron oxides, floor tile materials, etc.
4. Dyestuffs and pigments for instance paint pigments, food color, chrome yellow, titanium dioxide, etc.
5. Fertilizer production for example phosphates, nitrates, ammonium salts, among others.
6. Soap and Detergents e.g. bleach powders, detergent enzymes, and emulsifying agents.
7. Food industries for example whey, milk, egg products, soya protein, etc.
8. Processing fruits and vegetables for example banana, coconut milk, tomatoes, etc.
9. Beverage such as tea and coffee.
10. Biochemical industries such as processing of yeast extracts, algae, enzymes, fodder antibiotics, etc.
11. Control of environmental pollution e.g. desulfurization of flue gas.

Which are the Quality Standards for Pilot Scale Spray Dryer?

Some of the quality standards that the best pilot scale spray dryer should comply with include:

• US FDA Standards
• ISO Standards
• CE Standards
• cGMP Standards

In short, before you invest in a new pilot scale spray dryer machine, you should consider everything in this guide.

In case you have any question or inquiry, feel free to contact Pilotech technical team.