How Long Does Contract Spray Drying Take?

TL;DR

Advanced Powder Dynamics (APD) handles contract spray drying through a staged process: lab evaluation, pilot dryer trials, scale up demonstration and full commercialization. Hendrik Grobler, Technical Sales & Business Development, says the first consultation happens within a day or three, lab evaluation within one to three weeks, and pilot trials and scale up demonstrations take three to six weeks each, putting full commercialization at six weeks to six months. CEO Will West notes APD has taken some clients from concept to commercial scale in five to six weeks.

• APD’s development path runs from a liquid specification and dryability lab evaluation, to pilot trials on a 2.5 kg/hour evap dryer, to optimization on a 23 to 25 kg/hour evap dryer, then a scale up demonstration and full commercialization.
• The initial consultation normally happens within a day or three of a customer’s request, and onboarding to the lab evaluation step takes no longer than three weeks.
• Pilot scale dryer trials and scale up demonstrations each take three to six weeks, and full commercialization reasonably takes six weeks to six months depending on customer requirements.
• APD has taken customers through the whole process in five to six weeks, though Will West cautions that this is probably not typical.
• Customer-side factors such as decision making speed, freezing specifications, holidays and executive travel are among the biggest influences on the timeline.
• APD’s three production lines handle commercial runs from 5 kg dry up to 25,000 kg dry.

What are the steps from formulation to commercial spray drying?

Hendrik Grobler: APD has developed a very robust trial development process over the years with many different products. It’s detailed and very specific, but it’s focused on the customer objectives. We start with the first level, which is a lab evaluation. It’s what we refer to as a liquid specification and dryability evaluation. The scope of work there will depend on what exactly the customer objectives are. Is it only tolling? Is it contract manufacturing? Is it formulation development or formulation improvement or adjustment? Or is it benchtop work related to cyclodextrin inclusion formulations? We will build the process around those objectives.

Once we have conducted the lab evaluation, we will propose the next step, which is pilot scale dryer trials. APD has two different dryers for this purpose. The one is the smallest dryer, what we refer to as a D5 dryer. That is basically a 5 pound per hour or 2.5 kilogram per hour evap dryer, and that is where we perform the initial trials. It’s a first step where we actually produce powder for the customer for his evaluation.

We go through liquid process development, the basic process development for formulation, for batching, and then we evaluate the feed process of the product: what is the viscosity, what are the temperature requirements, can we optimize concentration? Then basic dryer evaluation from a settings perspective and from a configuration perspective. Inlet temperatures, outlet temperature requirements, what would influence the product quality? Is it prone to heat scorching and denaturing? Are there shear factor issues involved? Is it a hygroscopic material, so can we foresee conveyance challenges? We go through a whole array of tests and trials, and while we go through this, we evaluate the product to see if it complies with the specifications.

Once we’ve achieved the specifications, we will send a full report to the customer with next step proposals. Those proposals are normally on our next higher up dryer, which is a 50 pound per hour or more or less a 23 to 25 kilogram per hour evap dryer. That is where we optimize the whole process that we evaluated on the first level. We look again at evaluation on the liquid side, batching sequence, batching time, batching optimization, equipment required, and then we optimize the process parameters, the dryer parameters, the run conditions, the configuration of the nozzles, the pumps, the venturis, the auxiliary equipment so that we can prepare ourselves towards the next step, which is normally a scale up demonstration.

That scale up demonstration would be a full run based on all the objectives and the process that we developed, to confirm, yes, we can achieve powder property requirements and specifications at scale. We understand the process on the liquid side, on the dryer side, and on the product handling side: packaging equipment, labeling requirements, quality requirements, and we look at cleaning and sanitation requirements so that we can prepare for a full production run.

The final step is full commercialization, and that is where we actually dry the product for the customer. We have three production lines, so we can handle anything from 5 kilograms dry up to 25,000 kilograms dry. Depending on the customer requirements, we would propose that specific production line.

Will West: The organization put a lot of time into outlining that in a way that can be broadly applicable as a process for new clients coming in or existing clients. We use it as a framework all the time. We adapt it when we need to, but we find that there’s not a lot of need for adaptation. For organizations that are trying to get a sense of how they could work with us, it’s a good overview. The next step for prospective clients is to talk to us. If they have questions about how we’d apply it in their unique circumstance, they should give us a call.

How fast can a spray drying project reach commercial scale?

Will West: We have cases where we’ve gone from the lab, the benchtop, the R&D, and then pilot level to commercial. All five of those levels scale in five weeks. Being able to take a client from concept to commercial level scale and delivery in five to six weeks is incredibly valuable, if not unmatched.

I should caveat. That’s probably not typical. We can control some things, but not all of them.

How long from first consultation to first production batch?

Hendrik Grobler: The first consultation after a customer contacted us with a specific request, whether it’s toll drying, whether it’s product innovation and development, or benchtop work, would normally happen within a day or three. Our reaction time is very quick. We follow up with customers so that we can determine the feasibility of the product, vet the customer, vet our capabilities, so the customer has the opportunity to vet our capacities and our capabilities and make a quick decision.

Critical for speeding up the process is to explain the whole process to the customer. What can he expect? What are the different steps or phases that we go through, so that he can plan around that? I have seen that that helps the customer. Once he has the big picture and he understands what is involved in the process, it gives him a better understanding of how he should plan from his side: his logistical requirements, how we should approach quality requirements or certification requirements, cleaning requirements, and then process optimization.

That is what speeds up the process. Initially, we will also discuss logistical requirements. Is it contract manufacturing? Is it toll drying? Should we provide the ingredients? Are they providing the ingredients? What are the volume requirements? And then what are the specific requirements with regards to formulation development, benchtop work on the cyclodextrin side, and how would we approach that.

So first consultation within a couple of days. The next step is the lab evaluation, and that is normally between one to three weeks based on the customer logistical requirements and how we fit that into our schedule. We have a lab technician, and we have an R&D team that supports that. I would say never longer than three weeks to go through the onboarding process and to get the customer to that first step for the lab evaluation.

The next step in the process is the pilot scale dryer trials, and that could take anything from three to six weeks until we provide the customer with a proposal report, a trial report. After that, it is scale up demonstrations, another three to six weeks, and then full commercialization. That depends on the volumes and the production line that we’re going to utilize and the customer’s time frame requirements.

I always brag about this because we have taken customers through the whole process within six weeks. It is possible. But to full commercialization, reasonably, anything from six weeks to six months depending on what the customer requirements are.

What speeds up or slows down a spray drying timeline?

Will West: Importantly, [it depends on] how quickly the customer wants or is willing or is capable of moving. We can certainly move much more quickly once they’re onboarded if they need to. But a lot of times, there’s a decision making process and some uncertainty within the customer about where they need to go, what they want to do, what their approach to the market or the product is or will be. Quite honestly, it sometimes takes the customer a lot of [time to] decide which direction they’re going to go.

Ulli Lindauer: I think it’s extremely important that the customer internally is very aware of their ability to make decisions quickly if a quick turnaround time is one of their objectives. Also understand that in order to be really fast, you have to freeze the specifications at some point. You cannot continue to improve and improve and improve, because the more iterations you want to go through, the longer the process will take.

Something else that we need to take into consideration for both sides is, it’s the middle of September. We just came out of Labor Day weekend. A lot of people were out the week before. A lot of people are out this week. So what is the availability like on the customer side? Thanksgiving is coming up in two months. Christmas is coming up. If a customer has rigorous project management on their side, that’s very, very helpful. Is travel coming up for the executives that could potentially delay the decision making? Those are things that are out of our control. We control them on our side, but there are a lot of variables that are mirror images of those variables on the customer side.

Edited for length and clarity from a recorded conversation with Hendrik Grobler and Will West and Ulli Lindauer.