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The aim of this paper is to discuss the usability of a newly designed partially stirred horizontal anaerobic bioreactor made from triple layer bag material Sioen B6070 and heated by circulating hot air. For verification of the possibility of processing typical agricultural fibrous substrate at relatively high solids content in this type of reactor, the semi-continuous mesophilic (40±3°C) anaerobic digestion of corn silage of KWS Atletico cultivar was conducted. The reactor with a total volume of 0.7 m3 provided 0.5 m3 working volume. Liquid slurry from the 1st stage of the agricultural biogas station Pustejov II was used as inoculum. The silage dosage was performed so that the reactor reached high methane production intensity at low volumetric production of the digestate for 120 days. The average organic loading reached 4.27 kgVS m−3 d−1 while the average hydraulic retention time decreased to 85 days. The dry biogas production intensity was 3.42 mN3 m−3 d−1 with an average methane content of 52.5 vol%. The specific methane production from corn silage was 0.419 mN3 kgVS−1. At the end of the test, the digestate contained 13–14 wt% of total solids (TS) and 82–85 wt% of volatile solids in TS. The bag-type digester with hot air heating can be used by small farmers where there is no viable biogas cogeneration.

In this study, we tested the high-solids thermophilic anaerobic digestion of separated cattle slurry solids inoculated by liquid digestate collected from the 1st stage of the wet process operated in an agricultural mesophilic biogas plant. The process without batch agitation (stirring) was carried out in a barrel bioreactor located in the incubator, whereas the process with batch agitation was carried out in a rotating drum bioreactor (rotation speed: 0.1 min−1). In both cases, the biomass batch was non-liquid and the content of total solids was 18.8 wt%. The processes were conducted discontinuously without any addition for 21 days. The total solids content of both batches decreased to about 15 wt%, with only slight liquefaction. The bulk density increased from 500 to 750 kg m−3. The highest biogas production was achieved consistently on the 7th day. During the 21-day period, the unagitated batch produced 0.120 mN3 of biogas, and the agitated batch produced 32.5% extra. The average CH4 content in biogas from the unstirred batch amounted to 47.7 vol.%, and biogas from the stirred batch reached 46.2 vol.%. The cumulative methane production rates from the unagitated and agitated batches were 0.095 and 0.121 mN3 kgVS−1, respectively. Thus, the agitation resulted in 28.5% higher methane yield.

This article presents partial results of the laboratory development of an anaerobic bioreactor designed for the physical modelling of (semi)continuous dry or wet anaerobic digestion processes. A horizontal cylindrical tank reactor of 0.4 m3 total capacity has been developed. The reactor allows the continuous stirring of a liquid batch or the intermittent stirring of a solid batch. The bioreactor has been used as a lab-scale digestor in the research project dealing with high-solids (dry) anaerobic co-digestion organic fraction of mixed municipal solid waste. The first experiment was performed on the mixture of MSW with corn silage (1:1) with the weight of 300 kg.

The paper presents the results of the model of anaerobic co-fermentation of cattle slurry with biscuit waste. It was confirmed that the waste from the food industry is a valuable biogas substrate. The highest specific production of methane (0.49 mN3·kgVS-1) was achieved in the co-fermentation of 20 wt% biscuit waste with cattle slurry. The feed mixture contained 22 wt% of total solids. The biscuit waste has the specific production of biogas 0.66 mN 3·kg-1 and the specific production of methane 0.38 mN 3·kg-1.

A laboratory experiment of two-stage mesophilic, low-dry mass, anaerobic digestion was carried out, focused on verifying the benefit of processing the biscuit meal EKPO-EB instead of triticale silage Agostino (GPS) and corn silage LG3266 in a regular batch for the agricultural biogas station in Pustějov. While anaerobic digestion of ensilages is largely difficult due to the content of lignocellulose, biscuit meal provides a high yield of biogas or methane, respectively, thanks to its high content of simple saccharides and lipids. When the original GPS (or the replacement EKPO-EB, respectively) represented 0.81% of weight of the daily input mixture dose for the first stage, the rise in volumetric methane production was 20% which is significant. The biscuit meal EKPO-EB decomposes almost completely in the first stage. Later, when the EKPO-EB represented 1.63% of weight of the daily input mixture dose for the first stage, the rise in volumetric methane production was 54% in the first stage and 16% in the second stage.

Abstract We describe aggressive immunosuppressive treatment of an adolescent with Susac's syndrome (SS), a disease of the microvasculature in the brain, retina, and inner ear. Because the immunopathogenesis of SS appears to have much in common with that of juvenile dermatomyositis (JDM), the patient was treated with an approach that has been effective for severe JDM. The patient's outcome provides evidence for the importance of prompt, aggressive, and sustained immunosuppressive treatment of encephalopathic SS.