Innovative Hydrodynamic Disintegrator Adjusted to Agricultural Substrates Pre-treatment Aimed at Methane Production Intensification—CFD Modelling and Batch Tests

Abstract

The study objective was to adjust the hydrodynamic disintegrator dedicated to sewage sludge pre-treatment (HDS) to work with agricultural substrate. This involved the development and implementation of a mathematical model of flow via the device’s domain. An innovative disintegrator (HAD—hydrodynamic disintegrator for agriculture) was designed, built, and tested based on the obtained results. The main improvements to the HDS include the implementation of shredding knives in order to overcome clogging by crushed substrate, and the application of ribs in the recirculation zone, contributing to the development of an additional structure damage zone. The challenge of this study was also to determine the operating parameters of the HDA that would provide for an increase in methane production with positive energy balance. The testing procedures, for which maize silage was selected, involved batch disintegration tests and biochemical methane potential tests. No clogging of rotor or spontaneous shutting off of the device, in other words, problems that had occurred in the HDS, were observed. The applied pre-treatment method permitted an increase in the methane potential of maize silage by 34.4%, 27.0%, and 21.6%, respectively for samples disintegrated at energy densities of 10 kJ/L, 20 kJ/L, and 35 kJ/L with net energy profit.

The Enhancement of Energy Efficiency in a Wastewater Treatment Plant through Sustainable Biogas Use: Case Study from Poland

“…Taking into consideration the above-mentioned facts, the most widespread is the application of the following substrates: organic fraction of municipal solid waste (OFMSW); fat, oil, and grease wastes (FOG); various agro-industrial by-products (e.g., fruit and vegetable waste, glycerol and slaughterhouse wastes) [52,53]. Among the mentioned substrates, the use of wastes characterized by significant fat content is of great interest.…”

Investigation into cavitational intensity and COD reduction performance of the pinned disc reactor with various rotor-stator arrangements

“…Several different cavitator designs have been successfully employed for advanced oxidation of dissolved organic compounds (a review provided in [1] , [6] , [7] ) and disinfection (a review provided in [2] , [8] ) of WW. These include orifice plates [9] , [10] , venturi tubes [10] , [11] , vortex cavitation [12] , and rotating devices [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [22] , [23] , [24] that will be hereinafter referred to as rotational generators of hydrodynamic cavitation (RGHC).…”

“…This, on the other hand, comes at the expense of a greater complexity of internal geometry and cavitation mechanism as opposed to fixed-geometry cavitators. Several different RGHC designs have been developed in the recent years, including dimpled rotors [14] , [15] , [18] , [19] , [21] , [23] vaned rotor–stator devices [20] , serrated discs [16] , [17] , [25] , [26] , [27] , and pinned discs [22] . Dimpled rotors have been proven effective in sludge solubilization [3] , [15] , destruction of cyanobacteria [18] and in esterification of vegetable oil [23] but are limited by relatively low liquid throughputs and somewhat modest COD removal performance.…”

Dairy Manure Digestate Age Increases Ultrasound Disintegration Efficiency at Low Specific Energies

“…US disintegration is often compared to hydrodynamic disintegration (HD), which is reported to have a lower energy consumption compared to US disintegration [32,33]. Zubrowska-Sudoł et al (2020) reported an sCOD increase of 6.5-185% at a HD energy dose of 210 kJ/L for maize silage [33], while in this study, the manure digestate of 22 days ultrasonicated with 3000 kJ/kg TS or 213 kJ/L resulted in an increase in the sCOD of 41%.…”

“…US disintegration is often compared to hydrodynamic disintegration (HD), which is reported to have a lower energy consumption compared to US disintegration [32,33]. Zubrowska-Sudoł et al (2020) reported an sCOD increase of 6.5-185% at a HD energy dose of 210 kJ/L for maize silage [33], while in this study, the manure digestate of 22 days ultrasonicated with 3000 kJ/kg TS or 213 kJ/L resulted in an increase in the sCOD of 41%. The obtained sCOD increases in this study are in the range of HD pre-treatment results; however, to the best of the authors' knowledge, no study has yet investigated the effect of HD disintegration on the digestate of an anaerobic digester.…”