Challenging opportunities in drying R&D

Keywords:

• Climate change; cost effectiveness; energy footprint; food security; innovation; intensification of drying rate; nanotechnology; physical footprint; quality

The explosive growth in the scientific and technological literature pertaining to thermal drying of diverse products in scores of dryer types utilizing a variety of energy sources applied in steady or time-varying manner, is obvious even to the casual reader of such literature. Arguably, IDS1978 held in Montreal, Canada heralded a watershed event that gave the proverbial shot-in-the-arm, which resulted in a sharp increase in drying research and development almost all over the world. Both academia and industry recognized the strategic role drying operations play in manufacturing in nearly all industrial sectors. It was like a mini-industrial revolution that encouraged industry-academia interactions and collaboration. The IDS series along with a number of similar sister conference series around the world stimulated rapid growth in multi- and interdisciplinary research in all aspects of drying from macro to nano scales.

This journal also plays a pivotal role in dissemination of peer-reviewed technical knowledge, which encourages further research and identification of new and innovative research themes. Collaborative research by highly networked teams with diverse expertise results in innovative approaches to design and optimization of dryers. More recently there is focus on control of dryers using advances in control theory, sensors as well as artificial intelligence. The goal is to produce high-quality products cost-effectively with small physical and energy footprints. Reduced greenhouse gas emissions is essential to mitigate climate change. The amount of energy consumed in numerous drying operations in diverse industries is such that its cumulative effect on climate change cannot be ignored. Use of renewable energy such as solar and wind is being explored utilizing advances in solar energy collection with concentrating collectors, various thermal energy storage devices along with variants of dryer designs. Optimal coupling of these technologies in a cost-effective manner depending on location and material to be dried is indeed a challenging multidisciplinary problem.

In order to encourage young researchers as well as established researchers in related fields to become aware of research and development needs in drying and related fields of sciences, engineering, technology, and computing, it is necessary to provide critical assessment of current knowledge in capsule form. Drying research requires knowledge of transport phenomena along with materials science. Expertise in modern computational technology as well as state-of-the-art analytical tools is crucially important as well. It is often difficult to find the wide range of expertise and physical facilities required at a single location. Today drying research team members may be in the same institution or be located on the other side of the globe. Empirical studies show that such teams are often more productive than disciplinary research teams in one location.

Numerous resources are available now for those keen on making a contribution to drying research. A free e-book is available on Professor Mujumdar's website, which contains numerous articles on Drying R&D needs and Opportunities.^[1]

There are a number of excellent critical reviews published regularly in this journal that are very useful to novices and seasoned researchers as they save a massive amount of time needed to digest relevant publications dispersed widely.^[2] Readers are encouraged to locate and study them carefully. Only a few relevant references are cited here.^[3–4]

In recent years, production of nanoparticles has become an important research theme with major applications in pharmaceuticals, advanced materials for batteries and fuel cells as well as foods. Also, it is well recognized by the FAO that food security will be a major global problem within a decade or two. It is obvious that enhanced drying technologies have a key role to play in the production and storage of perishable foods that need to be transported across continents cost effectively.^[5] Indeed without drying, natural and artificial, we would not have the global population at the level we now have. Since all harvests are seasonal, without preservation by dehydration, ago-products simply could not be stored for consumption between harvests or transported from surplus to deleted areas. Much remains to accomplish in utilization of renewable energy for drying and storage of grains and processed foods while retaining quality.

In closing, we believe that much remains to be accomplished in drying research, especially problem solutions requiring use of latest advances in computing, scientific analytical tools, and artificial intelligence.^[6,7] We look forward to innovative papers making definitive original contribution to current knowledge of drying science and technology.

Arun S. Mujumdar
Department of Bioresource Engineering, MacDonald college, McGill University, Ste. Anne de Bellevue, Quebec, Canada
[email protected]

Hong-Wei Xiao
College of Engineering, China Agricultural University, Qinghua Donglu, Beijing, China
[email protected]

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.