High Quality Fertilizers Based on Biomass Pyrolysis Bio-Oil and Char

This work is focus on describing the composition, lixiviability and effects on the plants of a novel NPK-C slow release organic fertilizer and soil improver based on biomass pyrolysis bio-oil fraction and char. A dual product-component, charcoal and oligomeric lignin, can be considered as a flexible matrix in the formulation of fertilizers, where a range of nutrients and additives could be included. Thus, a unique and valuable fertilizer for agricultural and horticultural applications can simply be specified and then formulated, which also can also return bio-carbon to the soil (carbon sequestration in form of solid organic carbon). The aim is to enhance the economic viability of the fast pyrolysis process, producing high value chemicals from part of the liquid and solid products, in this case high quality organic fertilizers. First plant growing test showed promising results. The treatments with novel fertilizers based on pyrolysis products compared to the control treatment showed better results in: germination percentage, biometric parameters (stem height, leaves´ number, etc) and physiological responses (chlorophyll level and fluorescence). Based on the first measurements, the NPK 8-16-8 had better results as a fertilizer. Nevertheless, different parameters evolution indicate that the slow release treatments based on the novel fertilizer need more time to achieve the plant growth but it reached higher values than the commercial one with the time. Leaching test results will evaluate this novel fertilizer slow release effect. The next step will be to design a longer duration plant growing test phase to study slow release effects on plants and over consecutive plantings without any extra fertilizer addition. More factors could be considered, such as different treatment concentration and composition, plant species, plant growing phases, etc.