Avaliação da biodegradabilidade aeróbia de efluentes vinícolas

Mestrado em Gestão Ambiental, Materiais e Valorização de ResíduosO presente trabalho pretendeu analisar a biodegradabilidade aeróbia de efluentes vinícolas e a aplicação prática do reactor do tipo Sequencing Batch Reactor (SBR) no tratamento desses efluentes. Os ensaios de biodegradabilidade realizados ao efluente permitiram avaliar a capacidade de degradação da matéria orgânica existente na sua composição. Os testes realizados demonstraram que, para todas as condições aplicadas, foram obtidas taxas de remoção de CQO acima dos 90%, após as 48h de operação. A partir destes ensaios foi ainda possível definir modelos de cinética biológica para o efluente em análise. A modelação efectuada, seguindo as cinéticas de degradação típicas de Haldane/Andrews ou de Monod, demonstrou que, para a concentração de sólidos de 1,5 gSSV.L-1, existe inibição pelo substrato, adequando-se o modelo de Haldane. Já nas restantes condições testadas (3 e 4,5 gSSV.L-1) não existiram parâmetros inibidores no sistema de tratamento do efluente vinícola, adequando-se o modelo de Monod. Posteriormente efectuaram-se ensaios em dois reactores SBR à escala laboratorial, com concentrações de sólidos semelhantes, 1,5 e 2,5 gSSV.L-1, definidas de acordo com os valores propostos em bibliografia para o tratamento deste tipo de efluente. Da análise dos resultados obtidos com a realização dos ensaios à escala laboratorial e adoptando os reactores do tipo SBR, foi possível concluir que os efluentes vinícolas podem ser tratados neste tipo de sistemas com sucesso. No entanto, verificou-se uma maior aplicabilidade prática do reactor com uma concentração de SSV de 2,5 gSSV.L-1, com maior eficiência em termos de remoção de carga poluente, principalmente perante cargas mais elevadas, e com um controlo laboratorial facilitado. Com os ensaios realizados foi ainda possível verificar que, para as condições operatórias aplicadas, a percentagem de remoção de CQO foi superior a 95%. Os resultados mais elevados registaram-se nas cargas 2 e 2,5 KgCQO.L-1, para a qual se obtiveram valores de 99% de remoção para os reactores SBR I e SBR II. ABSTRACT: This work evaluated the aerobic biodegradability of the winery effluents and the application of one type of technology – Sequencing Batch Rectors. The biodegradability tests allowed the evaluation of the capacity of degradation of the organic matter existent on their composition. The tests demonstrate that, for all the conditions applied, the COD removal rates were higher than 90%, after 48h of operation. With this kind of tests, was also possible to define biological kinetic models for the effluent in study. The mathematical modelling was performed using Haldane/Andrews or Monod degradation kinetics. For de biomass concentration of 1,5 gSSV.L-1, the best fit was obtained with Haldane model indicating the possibility of inhibition by substrate. In the others conditions tested (3 and 4,5 gSSV.L-1), the best fit was obtained with Monod equation, there were no parameters that could cause inhibition on the winery effluent treatment system. After the biodegradability tests and the kinetic modelling, was accomplished rehearsals SBR reactors at laboratorial scale, with biomass concentration of 1,5 and 2,5 gSSV.L-1. These conditions were defined following values proposed in bibliography for this kind of effluent treatment. The analysis of the results reached, led to the conclusion that winery effluents could be treated, successfully, with this kind of treatment systems (SBR). However, the accomplished rehearsals with the reactor of 2,5 gSSV.L-1 biomass concentration, showed more applicability to operate at real scale, with more efficiency on the organic matter removal, specially in the presence of highest load. With the accomplished rehearsals was also possible concluding that, operating with the applied conditions, the COD removal was higher than 95%. The higher results were obtained for the volumetric loads of 2 and 2,5 KgCQO.L-1, with COD removal rates higher than 99%, for both reactors SBR I and SBR II

Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

© 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

© 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide. Methods: A multimethods analysis was performed as part of the GlobalSurg 3 study—a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital. Findings: Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58–5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23–0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer. Interpretation: Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised. Funding: National Institute for Health and Care Research