If you have spent any time in the world of process safety, the story of the Design Institute for Emergency Relief Systems (DIERS), an extensive R&D program sponsored by 29 companies under the auspices of AIChE is likely a very familiar one. Let’s take a look at the more utilitarian outcome of the DIERS undertaking, the development of the bench scale low thermal inertia adiabatic calorimeter known today as the VSP2TM.
As we approach the 30 year anniversary of the original VSP in 2015, it bears the question: is the VSP2TM still relevant in the world of process safety testing, or is it ‘so 30 years ago?’ It would be easy to say absolutely and just move on, but really one of the best ways to answer this question is to look at the various ways that the VSP2TM and its predecessor, the VSP, revolutionized the process safety testing industry in the first place, to discern if those features continue to make it a viable and useful industry tool today.
A primary purpose of DIERS was evaluation of emergency relief vent requirements, including energy and gas release rates for systems under upset conditions and the effect of two-phase flow on the emergency discharge process. Born of the DIERS testing methodology and further expanded upon in 1995, the VSP2TM offers many features that make it ideal for obtaining critical upset process design data including:
- Utilization of a light weight test cell design that is configurable to unique customer scenarios for testing flexibility to simulate process conditions such as:
- Loss of cooling or agitation
- Accumulation or mischarge of reactants
- Contamination of batch
- Thermally initiated decomposition
- Resident incubation time
- In-situ liquid/gas dosing or sampling
- Unique heating system that prevents sample heat loss
- Temperature and pressure rise rates applicable to relief system design
- Automated Windows operation
- Compact construction
- Ability for high pressure injection or measured injection of reagents using a stainless steel syringe capable of withstanding high pressure
- Automatic pressure tracking
Additionally, adiabatic data obtained with the VSP2TM can be directly applied to process scale and used to characterize reactive chemical systems hazards and consequences that could occur due to process upset conditions and relief system actuation (e.g. venting).
So, is it relevant or not? The answer: definitely. See, industry never sits still, and the data provided by the VSP2TM continues to provide critical upset process design data that is important to companies seeking to safely improve their processes as they build their business. Need more convincing? Perhaps the biggest indicator of the relevance of the VSP2TM is the fact that it is still used by numerous chemical and pharmaceutical companies around the world, and our own laboratory includes three VSP2TM systems.
Of course, in some applications the VSP2TM is not the only tool that can do the job. In fact, we have a wide variety of instruments in our own labs that we utilize based on the client’s need. But, in many cases today, we find the VSP2TM to be the most viable and cost effective option.
As an industry leader, Fauske & Associates, LLC (FAI) is constantly seeking ways to improve our own calorimetry products and the world of process safety, but rest assured that when considering if the VSP2TM is still relevant or not, we believe the answer is a resounding yes.