Zeotech : Promising Soil Carbon and Nutrient Retention Trial Results
03/08/2022 | 05:51pm EDT
For personal use only
9 March 2022
PROMISING EARLY RESULTS FROM
SOIL CARBON AND NUTRIENT RETENTION TRIALS
Emerging mineral processing technology company, Zeotech Limited (ASX: ZEO, "Zeotech" or "the Company") is pleased to advise that it has achieved promising early-stage results from pilot-scale trials undertaken by Griffith University ("Griffith"). The trials were undertaken over a three-month period and completed in February 2022.
The encouraging results highlight the potential to sequester long-term soil carbon and endorse the Company's comprehensive dual stream research program in collaboration with Griffith. The aim of the program is to establish scientific validation for developing Zeotech products for applications in two high potential areas of carbon markets and agricultural nutrient management.
Treatments containing Zeotech products consistently exhibited higher organic matter/carbon contents than controls for all soil and organic amendment conditions.
The effectiveness of Zeotech products at protecting against organic matter/carbon loss was much higher than that of the natural minerals (natural zeolite and bentonite).
All materials exhibited high nutrient carrying capacity approaching 10% by weight. This is particularly promising for Zeotech products and expands potential for a competitive fertiliser delivery platform.
Nitrogen carrying capacity was observed at approximately two times greater, and phosphorous up to five times greater in Zeotech products when compared to natural zeolites and bentonites.
Desorption results indicate that a small proportion of the zeolite-held nutrients are immediately available to plants. This highlights the potential for a controlled (slow release) delivery of nutrients to plants in the soil environment.
Griffith University, School of Environment and Science | Australian Rivers Institute, Dr. Chris Pratt commented:
"Achieving organic soil carbon protection levels averaging 25% compared with controls, combined with high nutrient carrying capacity and slow-release potential are exciting early findings.
The results increase confidence in achieving desired outcomes in the comprehensive program underway at Griffith, aimed at research targeting the development Zeotech products for improved fertilizer delivery and enhanced soil carbon retention."
Zeotech, Managing Director Peter Zardo added:
"These promising results will inform the design of larger trials that will commence within weeks and further validate Zeotech's commitment to developing solutions to enhance sustainable farm productivity and expand carbon market opportunities for the agricultural sector.
The Company is continuing process development aimed at producing a lower cost Type A zeolite, specifically designed for agricultural applications, with samples having already been produced and ready to be used in the comprehensive dual-stream research program.
Zeotech values the collaboration with Griffith University, one of Australia's most highly specialised and well-resourced teams in the area of agricultural carbon and nutrient management and acknowledges the efforts of Griffith summer student's Renee Medland (carbon retention) and Mark Donaldson (nutrient retention/interception) in supporting Dr. Pratt during the successful early pilot-scale trials."
Griffith University Research Trials
The experimental trials were targeted at:
Soil organic carbon sequestration - evaluating the capacity of the synthetic zeolites produced under the Company's proprietary process to protect organic carbon amendments; and
Nutrient interception and retention - evaluating the nutrient carrying capacity of synthetic zeolites produced under Zeotech's proprietary process and competitiveness with conventional chemical fertiliser products, together with plant availability of zeolite- held nutrients.
The encouraging outcomes will inform the design of the larger trials, scheduled to commence in the coming weeks. Establishing the form and stability of this protected organic matter/carbon is a key step in evaluating the potential for the Company's synthetic zeolite product(s) to sequester long-term stable soil carbon.
Early research outcomes validate the potential for Zeotech products in carbon markets, which are being developed in Griffith's dual-stream program that commenced in November 20211.
Soil Organic Carbon Sequestration
The research comprised a total of individual treatments covering two soil types, two organic soil inputs, and four carbon protection minerals. Results were benchmarked against controls containing soil only and organic compound only.
Following the three-month trial, the organic carbon content of each treatment was determined by the 'loss on ignition method.'
[fig1] Set-up of the treatment incubations prior to mixing
1 ASX release 08/11/2021 "Zeotech to develop products for Carbon Markets in collaboration with Griffith University"
[fig2] Organic matter (OM) remaining in treatments at end of trial with
OM content of control: initial and control: final shown for comparison description.
Treatments containing Zeotech products consistently exhibited higher organic matter/carbon contents than the controls for all soil and organic amendment conditions. The naturally occurring materials (natural zeolite and bentonite) exhibited higher organic matter contents than the controls for all soil and organic amendment additions apart from peat moss added to the sandy soil.
[fig3] Organic matter (OM) protection by treatment, expressed as a % of OM retained relative to OM lost by controls
The results highlight the effectiveness of Zeotech's products at protecting against organic matter/carbon loss was much higher than that of the natural minerals (natural zeolite and bentonite) [fig3] shows the organic matter/carbon protection by mineral treatments, expressed as a percentage of the organic matter/carbon retained relative to the organic matter/carbon lost by the controls (where the controls equal 0%).
The research incorporated Zeotech products in bead and powder form, as well as two natural zeolites (clinoptilolite and mordenite). Doses of phosphorous and nitrogen solution were sequentially added to the batches.
Upon completion of the dosing and air-drying phase, the samples underwent a desorption process using deionised H₂O (general solvent), citric acid (targets phosphate minerals) and potassium chloride (targets surface-sorbed nitrogen compounds). This step was conducted to evaluate the retention stability of the nutrients on the zeolite material.
[fig4] (a) ammonium-N and (b) phosphate-P retention capacities of the zeolites across multiple dosing events.
All materials exhibited high nutrient carrying capacity, approaching 10% by weight for the Zeotech products, which was reflected by increased material masses following drying after the nutrient dosage stage. Nitrogen retention capacity is approximately two times greater in the Zeotech products and held up to five times more phosphorous than natural zeolites.
[fig5] Desorption results for ammonium-N and phosphate-P for each of the desorption agents: a (H2O), b (citric acid) and c (KCl). 1 = natural clinoptilolite zeolite, 2 = natural mordenite zeolite, 3 = Zeotech Type A beads, 4 = Zeotech Type A powder.
Nutrient desorption (release) results are represented as a percentage of nutrient released relative to the amount of nutrient retained in the loading phase. Nutrient release in the one-off desorption solutions were generally low (<20%) and are more favourable for the Zeotech products when compared to the natural zeolites. Desorption results indicate that a small proportion of the zeolite-held nutrients are immediately available to the plants. This holds promise for controlled (slow release) delivery of nutrients to plants in the soil environment.
Comprehensive Dual-StreamAgri-Product Research Program
Zeotech commenced a comprehensive dual-stream research program in collaboration with Griffith University in November 20212. The research program involves pilot trials and establishing scientific validation aimed at developing Zeotech product applications in two high potential areas of carbon markets and agricultural nutrient management.
The goal of the program being undertaken by Griffith is to conduct research that will underpin agronomic opportunities for Zeotech products that provide competitive advantages comparable to existing soil amendments such as fertilisers and soil conditioners, with the early and substantial focus on the 'carbon markets' program.
2 ASX release 08/11/2021 "Zeotech to develop products for Carbon Markets in collaboration with Griffith University