Development of fertilizer formulation from zeolitic concentrates obtained from WTP sludge and microorganisms

• Grant number: 22/09773-1
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: September 01, 2022
• End date: August 31, 2025
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Agreement: SABESP
• Principal Investigator: Cauê Ribeiro de Oliveira
• Grantee: Raquel Cardoso Machado
• Host Institution: Embrapa Instrumentação Agropecuária. Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA). Ministério da Agricultura, Pecuária e Abastecimento (Brasil). São Carlos , SP, Brazil
• Company: Ministério da Agricultura, Pecuária e Abastecimento (Brasil). Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA). Embrapa Instrumentação Agropecuária
• Associated research grant: 20/12210-3 - Development of technological alternatives for the use of ETA sludge as raw material for the production of controlled release fertilizers, AP.PITE

Abstract

This project will have as main objective to define the conditions for the formulation of fertilizer compounds from zeolitic concentrates containing encapsulated microorganisms. Formulations of thermoplastic starch plasticized with urea will be selected to obtain porous granules of controlled hydrophilicity/solubility. The choice of starch as a processing base comes from the teams' previous experience, which showed that the addition of 15 to 30% urea is capable of plasticizing the starch, allowing processing at low ambient temperatures. Urea is subsequently used as a fertilizer and, at these levels, it reaches the minimum registration specifications as an NK fertilizer product. The matrices will be reinforced with contents of up to 50% of the zeolitic concentrates produced in result 1, to allow processability in extrusion or pelleting and to provide cation exchange properties. Encapsulation will be done by adding microorganisms to the starch:concentrate mixture, still pasty, at a temperature below 40ºC. Given the processing conditions of the zeolitic concentrate, the addition to the starch will be made from the post-synthesis mixture without drying, thus taking advantage of all the residual K+ present as a fertilizer. The final product, therefore, will be an NK fertilizer with a content determined throughout the research. The matrices should be tested with the microorganisms to optimize the multiplication capacity by the gradual consumption of the matrix itself, during the application. The challenges will involve the proper selection of materials, production processes under mild conditions (low temperature) and optimization of spore carrying capacity (maximum concentration x optimized properties).The fertilizers will be processed via extrusion or pelleting at a temperature below 40ºC, to preserve the microorganisms. The conformation as pellets will enhance the interactions of the sources and give adequate conformation of the fertilizers in the form of granules or pellets. The levels of nutrients present in granules/pellets of fertilizers will be measured according to the methodology proposed by the Ministry of Agriculture. The dispersion of the zeolitic concentrate in the organic compound and the homogeneity of the mixture, as well as the structure of the granules/pellets will be evaluated by Scanning Electron Microscopy-Energy Dispersive X-ray and Transmission Electron Microscopy for potentially important chemical and morphological characterization for the fertilizer solubilization process. The hardness of the pellets and resistance to destructuring by physical action/friction and immersion in water will also be evaluated. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MACHADO, RAQUEL CARDOSO; VALLE, STELLA F.; CHAO, ZARA REGINA SOARES; RIBEIRO, CAUE. Valorization of Alum Sludge Waste through Zeolite Synthesis for Sustainable Fertilizer Production. MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS, v. 27, p. 9-pg., 2024-01-01. (22/09773-1, 20/12210-3, 23/01549-8)

MACHADO, RAQUEL CARDOSO.; VALLE, STELLA FORTUNA DO; SENA, THAIS BEATRIZ MIQUELETI; PERRONY, PAUL ESTEBAN PHEREZ; BETTIOL, WAGNER; RIBEIRO, CAUE. Aluminosilicate and zeolitic materials synthesis using alum sludge from water treatment plants: Challenges and perspectives. WASTE MANAGEMENT, v. 186, p. 15-pg., 2024-06-13. (22/09773-1, 20/12210-3, 23/02665-1, 23/01549-8)