Skip to main content

Planting new seeds for agricultural technology

Date

Corn seeds falling from a hand into a bag

In the agricultural sector, making sure seeds have the best chance to sprout and flourish is essential. Often, seeds are coated in a protective material such as fertiliser and pesticide to ensure they succeed. However, the process of coating them – and achieving uniformity and consistency across seeds – is a technological challenge.

Dr Mehrdad Pasha completed a 12-month Knowledge Transfer Secondment with Syngenta, a global agricultural technology company, to find a solution. The research has implications for material processes, including medicine.

This project was sponsored by the UKRI Impact Acceleration Account.

Impact

  • Knowledge discovery: developed a new method for simulating corn coating methods
  • Economic impact: partnered with a sector leader to improve processes, save resources, and advance technology.

Key information

  • Major funders: UKRI Impact Acceleration Account, Engineering and Physical Sciences Research Council (EPSRC)
  • Partners and collaborators: Syngenta
  • Disciplines: chemical engineering
  • Investigators: Dr Mehrdad Pasha, Professor Mojtaba Ghadiri.

Coating corn seeds

While working on his PhD at the University of Leeds, Mehrdad had developed a method for predicting flow, mixing and coating of corn seeds.

Seeds are usually coated in a gradual accumulation of successive layers of an adhesive and protective material, making the seeds less prone to dusting and cracking, which in turn reduces the loss of active ingredients.

During the short time it takes to coat, the seed particles grow by surface layering, accompanied by wetting, adsorption, abrasion and drying.

These physical mechanisms in seed coating are poorly understood -- commercial organisations often consider the practice more of an art. The Discrete Element Method (DEM), which simulates the motion and mechanical interactions of particles, is a valuable tool for predicting the processing behaviour of particles.

The technique, which uses simulation tools, can be applied to large seed processing systems. Syngenta were keen to acquire and embed this method, seeing it as the first step towards developing a virtual laboratory for conceptual process design of seed processing.

The secondment involved the advanced modelling of seed processing, to:

  • Develop a generic coating model in DEM simulations for predicting the coating uniformity of the particles
  • Optimise process parameters to improve the coating uniformity of corn seeds in a rotary batch coater
  • Establish scale-up rules for the rotary batch seed coaters.

The process of coating particulate solids in thin film layers happens in many contexts, from coating seeds to medicinal tablets, meaning this work could improve the efficiency of processing systems across sectors.

Global impact

In addition to an enhanced strategic partnership between the University of Leeds and Syngenta, the secondment resulted in a shared understanding of new coating formulations and improved coating uniformity.

Less coating material can be used, which brings environmental benefits and improves seed coating quality. As a consequence, there will be higher crop yields due to an improvement in the seeds’ enhanced germination potential. On a global level, this will help improve the world’s food supply.

As Mehrdad Pasha and Principal Investigator Mojtaba Ghadiri explain: "Increased insight into key phenomena involved in spray coating for seeds has provided the impact potential for significant improvement of seed quality and germination efficiency for Syngenta products."

The understanding developed through seed coating and DEM can be directly transferred and applied to the coating of tablets in the pharmaceutical industry for improved targeting and efficacy of medicines in tablet form.

Following the Knowledge Transfer Secondment, Syngenta decided to expand its in-house expertise and activities in this field.

To build upon the understanding developed during this project, they have created an associated role to continue the work, with currently two internal projects emanating from this KTS. They have also purchased computer hardware and a DEM software licence to implement the models in-house.

Findings from this Knowledge Transfer Secondment were disseminated widely through publications and at conferences nationally (UKTPF) and internationally (World Congress 2014, AIChemE/PTF 2016, PARTEC 2016, Powders and Grains 2017).

Overall, the outcome has increased insight into key phenomena of mixing and coating, leading to better coatings, together with potential plans to develop a virtual laboratory for advanced seed processing.