Alternative method for producing organic fertiliser from anaerobic digestion liquor and limestone powder: High Shear wet granulation

Abstract

Publisher rights This is the author's version of a work that was accepted for publication in Powder Technology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Powder Technology, VOL 233, 01/2013 General rights Copyright for the publications made accessible via the Queen's University Belfast Research Portal is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. energy production are considered as waste. This has a negative impact on the sustainability of AD processes because of the financial outlay required to treat digestate before being discharged into municipal water treatment plants or natural water bodies. The main aim of research was to investigate feasibility of producing an organic fertiliser using anaerobic digestate and limestone powders as the raw materials employing a high shear granulation process. Two-level factorial experimental design was used to determine the influence of granulation process variables on, the strength, resistance to attrition and yield of the granules. It was concluded from the study that it is technically feasible to produce organic fertiliser granules of acceptable strength and product yield. Increasing the liquid-to-solid ratio during granulation leads to increased granule strength and better product yield. A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPTAlthough the strength of the granules produced was lower than typical strength of commercial synthetic fertiliser granules (about 5 to 7 MPa), this could be improved by mixing the digestate with a polymeric binder or coating the particles post granulation.

High shear granulation of binary mixtures: Effect of powder composition on granule properties

“…XRD and particle size analysis of the powders Limestone powder supplied by Kilwaughter Chemicals Ltd., UK, was used as one of the raw materials. X-ray diffraction (XRD) analysis of the powder limestone that it was mainly composed of calcite and quartz minerals [4]. Value tea purchased from Tesco was used as the second powder component in the granulation experiments.…”

“…[4]. In this procedure a sample of the granules (5 g) is subjected to attrition forces by shaking them mechanically on a sieve shaker and recording the mass loss as a function of time.…”

“…Some of the advantages of HSWG include increased bulk densities, improved flow properties, reduced powder segregation and better handling properties. HSWG has been applied in several industries, for example, detergent, food, pharmaceutical and agricultural, to enhance the powder processibility [1][2][3][4][5].…”

Process analytical technology (PAT) approach to the formulation of thermosensitive protein-loaded pellets: Multi-point monitoring of temperature in a high-shear pelletization

“…6). In the literature Mangwandi et al (2013) found that tensile strength is increasing with increasing impeller Fig. 7.…”

An analysis of the chemistry, mineralogy and texture of waste dolomite powder used to identify its potential application in industry

“…On the other hand, a material that in one type of industry is considered as waste, can be useful in another manufacturing process (Zhang et al 2008, Disfani et al 2011, Park & Chertov 2014. Depending on the type of waste material, the potential ways in which it could be used for economic purposes are as follows: building engineering, where it could be used as an additive in the production of concrete or as a binding material for the production of cement, replacing Portland cement clinker (Kinuthia & Nidzam 2011, Bilgin et al 2012, Dell'Orso et al 2012, Chen et al 2013, Helios-Rybicka et al 2013, Romero et al 2013, Alaibdo et al 2014; road engineering, where it can be considered as a material for soil stabilization, or to create road surfaces (Poon & Chan 2006, Engelsen et al 2012, Galvín et al 2013; agriculture, where it could be used as a fertilizer or to neutralize soil acidification (Harris & Lottermoser 2006, Mangwandi & Tao 2013, Tozsin et al 2014. Currently, broadly understood environmental protection is also considered to have an economic basis, as environmental standards need to be met.…”