Recovery of nutrients from the liquid fraction of digestate : Use of enriched zeolite and biochar as nitrogen fertilizers
Kocatürk-Schumacher, Nazlı Pelin ; Zwart, Kor ; Bruun, Sander ; Jensen, Lars Stoumann ; Sørensen, Helle ; Brussaard, Lijbert - \ 2019
Journal of Plant Nutrition and Soil Science 182 (2019)2. - ISSN 1436-8730 - p. 187 - 195.
biogas digestate - clinoptilolite - double-pot technique - enriched sorbent - initial loading - slow release N fertilizer
The liquid fraction after liquid/solid separation of biogas digestate has a high potential as a fertilizer due to its high nutrient concentration. However, the direct application of digestate in agricultural fields results in practical problems due to its voluminous nature. One solution to this could be to concentrate nutrients onto sorbents such as biochar or zeolites, which can subsequently be used as a fertilizer. This study investigated the ability of biochar and zeolite ‘clinoptilolite' enriched with digestate nutrients to supply nitrogen (N) when used as a fertilizer. A pot experiment with ryegrass was conducted to test the effect of a nutrient-enriched biochar and clinoptilolite by determining plant biomass growth and N uptake. This included untreated biochar and clinoptilolite as controls and two levels of N application (15 and 45 mg N per pot) each at two initial loading ratios (low and high). Nutrient-enriched biochar and clinoptilolite increased plant biomass yield (up to 1.02 and 2.39 g per pot) and N uptake (up to 11.23 and 39.94 mg N per pot) compared to the untreated sorbents treatments. Initial loading ratio had a significant effect on plant biomass response and apparent N recovery (ANR) for enriched clinoptilolite, and lower initial loading ratio improved plant growth. In contrast to clinoptilolite, higher initial loading ratio resulted in higher ANR. In conclusion, our results reveal that N released from enriched clinoptilolite and biochar could be taken up by the plants, clinoptilolite performed more effectively than biochar, and initial loading ratio affected the performance of the sorbents when used as a fertilizer.
Does the combination of biochar and clinoptilolite enhance nutrient recovery from the liquid fraction of biogas digestate?
Kocatürk-Schumacher, Nazlı Pelin ; Zwart, Kor ; Bruun, Sander ; Brussaard, Lijbert ; Jensen, Lars Stoumann - \ 2017
Environmental Technology 38 (2017)10. - ISSN 0959-3330 - p. 1313 - 1323.
Biochar - clinoptilolite - liquid fraction of digestate - nutrient recovery - sorption
Concentrating nutrients on biochar and clinoptilolite and subsequently using the nutrient-enriched sorbents as a fertiliser could be an alternative way to manage nutrients in digestate. In this study, we investigated the use of biochar and clinoptilolite columns in removing ammonium, potassium, orthophosphate and dissolved organic carbon (DOC) from the liquid fraction of digestate. Our objectives were to investigate the effect of the initial loading ratio between liquid and biochar on nutrient removal, and to investigate the effect of combining biochar with clinoptilolite on nutrient and DOC removal efficiency. Increasing the initial loading ratios increased nutrient concentrations on biochar to 8.61 mg NH4-N g−1, 1.95 mg PO4-P g−1 and 13.01 mg DOC g−1, but resulted in decreasing removal efficiencies. The combination of biochar and clinoptilolite resulted in improved ammonium, potassium and DOC removal efficiencies compared to biochar alone, but did not significantly change PO4-P removal efficiencies. Removal efficiencies with combined sorbents were up to 67% for ammonium, 58% for DOC and 58% for potassium. Clinoptilolite showed higher removal efficiencies compared to biochar alone, and combining clinoptilolite with biochar improved only total P removal efficiency. Concentrating nutrients with clinoptilolite and biochar may be an option when both sorbents are available at low cost.
Recovery of nutrients from biogas digestate with biochar and clinoptilolite
Kocaturk, N.P. - \ 2016
Wageningen University. Promotor(en): L. Stoumann Jensen; Lijbert Brussaard, co-promotor(en): S. Bruun; Kor Zwart. - Wageningen : Wageningen University - ISBN 9789462578234 - 130
biochar - clinoptilolite - digestate - nutrients - waste management - fractionation - growth - biochar - clinoptiloliet - digestaat - voedingsstoffen - afvalbeheer - fractionering - groei
The liquid fraction of digestate contains nutrients which makes it a valuable fertiliser in agricultural crop production systems. However, direct application of digestate may raise practical and environmental problems. Therefore, processes to concentrate nutrients have been proposed aiming not only to treat the liquid fraction of digestate to overcome the problems related to direct application, but also to recover the nutrients of which natural reserves are being depleted such as phosphorus and potassium.
In this thesis, the focus was on the evaluation of the use of clinoptilolite and biochar for nutrient recovery from the liquid fraction of digestate; and to investigate the further use of these nutrient-enriched materials as fertiliser.
This thesis showed that sorption with clinoptilolite and biochar can be a promising technology to recover nutrients from liquid fraction of digestate. Using biochar and clinoptilolite provides concentration of nutrients and, thereby, volume reduction which allows for savings on storage, transport and application of the voluminous liquid fraction of digestate. The end-products are digestate-enriched clinoptilolite and enriched biochar can act as N fertilisers.
Sturen in melkproductie en melksamenstelling : verkennende studie naar de effecten van Clinoptiloliet
Verwer, C.M. ; Eekeren, N.J.M. van - \ 2011
[S.l.] : Louis Bolk Instituut (Biogeit rapport / Louis Bolk Instituut 23) - 25 p.
geitenhouderij - clinoptiloliet - voedertoevoegingen - melkproductie - melksamenstelling - biologische landbouw - goat keeping - clinoptilolite - feed additives - milk production - milk composition - organic farming
In dit Biogeit rapport wordt een praktijkonderzoek beschreven naar de effecten van Clinoptiloliet op de melkproductie en melksamenstelling van geiten. Voor het onderzoek zijn 50 nieuwmelkte geiten gebruikt. De geiten werden verdeeld over 2 groepen; een controle-groep en een Clinoptiloliet-groep. Clinoptiloliet werd verstrekt nadat alle dieren minimaal 6 weken in lactatie waren. Gedurende 6 maanden zijn om de 6 weken melkmonsters genomen om per individu de melkproductie, vetgehalte en eiwitgehalte te bepalen. Bij de start van het onderzoek en aan het einde van het onderzoek is ook het celgetal per geit bepaald. Clinoptiloliet had geen (neven)effect op de melkproductie en het eiwitgehalte van de melk. Clinoptiloliet had een positief verhogend effect op het vetgehalte van de melk met ongeveer 0.1-0.4 %.