Conceptual design of the mobile granulation line for production fertilizers from digestates and ash mixtures

Abstract

Abstract. Paper presents a concept of the mobile line for the production of granulated fertilizer from digestates and ash mixtures. The main assumption of the designed line is its mobility which allows line work in the place of production of digestate. The premise for developing such model of line was the fact that the transport of highly hydrated digestate, as well as its dried form, is not advisable for economic reasons. More advantageous solution is to collect the digestate at the place of its production and it is processed into a fertilizer. Loose components, characterized by high bulk density, can be delivered to the place of production and the same means of transport can be used to transport the produced fertilizer to warehouse. This production model allows to process the digestate produced in several biogas plants, using one production line and reducing the cost of production. of fertilizer granules and the mobile line is transported to the next post-fermentation production point. Based on an analysis of the raw material characteristics and preliminary research on the raw materials mixture granulation process it was assumed that the stage of 3 hrs mixture stabilization time is required in the line.

Impact of sulphuric, hydrochloric, nitric, and lactic acids in the preparation of a blend of agro-industrial digestate and wood ash to produce a novel fertiliser

“…2 a). This agrees with the results of Wróbel et al [33], who described that only 3 hours of stabilisation after the blending of agricultural waste digestate and biomass ash is required before pelletisation. It is important to mention that for the preparation of the blend, they employed dewatered digestate in order to have a final blend with a moisture content of 18 wt.…”

“…%. The stabilisation that Wróbel et al [33] referred to in their study was regarded in our present work as physical stabilisation, which is mainly the result of the hydration of oxides to hydroxides and, to a lesser extent, later the subsequent formation of carbonates. In this way, this self-hardening process which is required prior to the granulation relies on the alkalinity of the ashes and specially on the calcium content [34].…”

“…Wróbel et al [33] proposed an economical way of achieving the granulation of the organic wastes treated with ashes by means of creating a mobile granulation unit (i.e. decentralised plant).…”

The Future Agricultural Biogas Plant in Germany: A Vision

“…This could comprise components for pretreatment, for elimination of inhibiting substances, different reactor stages such as separate hydrolysis or ex-situ methanation for conversion of gases, treatment of digestate and the processing or upgrading of produced biogas. Some of these parts can be easily included as modular components in biogas plants (e.g., pretreatment or digestate treatment modules [169]), others are still under investigation or need to be developed (e.g., modules for removal of process inhibitors, such as ammonia stripping or magnesium ammonium phosphate precipitation [170]). Activation of modular components on demand requires feedstock and process surveillance and reliable control systems.…”

Biomass Energy Technologies from Innovative Dairy Farming Systems

“…There is great demand for such a type of fertilizer, in particular, in agricultural and horticultural production. The main component of fertilizer, namely, post-fermented mass, is rich in nutrients N, P, and K in mineral form, directly available for plants [6]. This paper presents the following in a detailed manner:  a modern (innovative) system of dairy cattle breeding that enables maintaining animal welfare including innovative solutions with regard to mechanization, and milk and natural fertilizer production;  animal security systems for high-quality feed suitable for the age group and lactation period; and  a complex system of management for natural fertilizer through methane fermentation (energy biomass) and further production of organic fertilizer.…”