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This research work proposes the scale-up evaluation in terms of biological and filtration performance from laboratory to pilot-scale of an anaerobic membrane bioreactor (AnMBR) co-digesting raw microalgae and primary sludge. Best operating conditions for this scale-up were energetically and economically assessed based on laboratory results. Economic balance showed 3% higher annual costs when operating a reactor at 100 d solids retention time (SRT) compared to 70 d SRT. Energetic balance showed a 5.5-fold increase in heat demand working at thermophilic temperature comparing to mesophilic. The AnMBR operating conditions were set at 70 d SRT and 35 °C. The pilot-scale and lab-scale co-digesters performed similarly in terms of biogas production and system stability. 154 mLbiogas·d-1·L-1reactor were produced at pilot-scale, corresponding to methane yield of 215 mLCH4·gCODinf-1. AnMBR filtration at both laboratory and pilot-scale showed stability working at permeate fluxes of 4.2-5.8 L·m-2·h-1.

Harvested microalgae Chlorella spp. and primary sludge were co-digested in a laboratory-scale anaerobic membrane bioreactor (AnMBR) under thermophilic conditions (55 °C). The system was run for 700 days divided into four experimental phases to determine the influence of the organic loading rate on the process performance and the microbial community. The rise in organic loading rate from 0.17 to 0.5 gCOD·L−1·d−1 led to a 35% improvement in methane production. The system reached 69% biodegradability working at 0.5 gCOD·L−1·d−1 and a high solids retention time (70 d), indicating the efficient conversion of biomass into biogas through the AnMBR configuration while avoiding possible inhibition by free ammonia. The thermophilic AnMBR provided a stable microbial community dominated by hydrolytic and fermenter members such as Coprothermobacter, Fervidobacterium and Hydrothermae. Syntrophic oxidisers such as W5 were also key in propionate degradation and produced intermediates for later conversion into methane.

Anaerobic co-digestion of primary sludge and raw microalgae (Scenedesmus and Chlorella) was performed in a lab-scale semi-continuous anaerobic membrane bioreactor to assess the biological performance and identify the microbial community involved in the co-digestion process. The reactor was operated at 35 °C for 440 days, working at a solids retention time of 100 days. The system achieved 73% biodegradability and showed high stability in terms of pH and volatile fatty acids. An enriched microbial community was observed. Of the several phyla, Chloroflexi and Proteobacteria were the most abundant. Cellulose-degraders phyla (Bacteroidetes, Chloroflexi and Thermotogae) were detected. Syntrophic microorganisms played an important role in intermediate degradation, enhancing methane production, mainly carried out by Methanosaeta. A nutrient-rich effluent (400 mg NH4-N·L−1 and 29 mg PO4-P·L−1) and digestate (860 mg N·L−1 and 151 mg P·L−1) were obtained. The bio-nutrients released from anaerobic co-digestion could be reused for microalgae cultivation or agricultural applications.

Resumen Objetivo Valoracion del componente acetabular no cementado en protesis total de cadera por artrosis secundaria a fractura de cotilo. Material y metodo Estudio prospectivo de 24 pacientes con edad media de 56 anos (rango: 28-77) y seguimiento medio de 8,4 anos (rango: 5-15), que fueron tratados con acetabulo no cementado atornillado. El tiempo medio entre la fractura y la protesis fue de tres anos (rango: 5 meses-14 anos). La fractura habia sido tratada conservadoramente en 15 casos y con fijacion interna en 9 casos. Se realizo valoracion clinica con la escala de Harris y radiografica, con especial interes en el acetabulo. Resultados La escala de Harris media se incremento de 35 puntos (rango: 22-52) a 77 (rango: 45-94). Hubo tres aflojamientos de cotilo, dos con osteolisis que fueron revisados y uno con radiolucencia continua. El vastago femoral preciso revision quirurgica en un caso. Hubo un caso de infeccion profunda y una luxacion tardia postraumatica. La funcion de supervivencia de la artroplastia por cualquier causa a 12 anos fue del 78,4%. Discusion y conclusiones Son escasos los estudios al respecto y todos con pequeno numero de casos. La tasa de fallos acetabulares es superior que la tasa en los casos no traumaticos. La protesis no cementada es un tratamiento adecuado para las secuelas de fractura de cotilo.

Objective To evaluate the outcomes of cementless acetabular component for post-traumatic arthritis after acetabular fracture. Material and method A prospective study of twenty-four patients with a mean age of 56 years (range: 28–77) and a follow-up 8.4 years (range: 5–15) treated with cementless total hip arthroplasty. The time from fracture to total hip arthroplasty was 3 years (range: 5 months-14 years). The fracture had been treated conservatively in 15 cases and with internal fixation in 9 cases. A clinical assessment was made using with Harris hip score, along with radiology with special interest in the socket. Results Harris hip score increased from 35 points (range: 22–52) to 77 (range: 45–94). Unstable acetabular fixation was seen in 3 cases, 2 with osteolysis that required revision and 1 with a complete radiolucent line. The stem required revision in 1 case. There was 1 case of deep infection and 1 post-traumatic late dislocation. Survival for any cause at 12 years was 78.4%. Discussion and conclusions There are few studies on this topic, and all with a small number of cases. Acetabular failure rate is higher than routine total hip arthroplasty for non-traumatic osteoarthritis. Cementless total hip arthroplasty is a suitable treatment for post-traumatic arthritis after acetabular fracture.