A compact high-rate anaerobic reactor configuration for the treatment of effluents with high lipid content

ManuscriptExisting high rate anaerobic technology such as UASB, EGSB and IC reactors based on granular sludge is not robust when applied to industrial effluents with high lipids content. After discovering the potential of converting fat and long chain fatty acids to methane, the development of a compact high rate anaerobic reactor technology for the treatment of effluents of high lipid content was pursued. In this paper the basic principles of the IASB technology (patented) are described and results of a pilot plant treating a slaughterhouse effluent are presented. An organic loading rate of 16 kg COD/m3.day was applied being 63% of fat. Effluent VSS were around 500 mg/L. COD removal efficiency was consistently above 80% and excessive LCFA accumulation was prevented (<1 g COD-LCFA/gTS) in the reaction section of the IASB reactor.Nevertheless, LCFA accumulated again when the organic loading rate was increased from 2 to 3 and 5 kg COD m-3 d-1. The profiles of LCFA, obtained with OMW digestion, were different from previous studies with synthetic effluents. At the beginning of reactors operation, oleate was the main LCFA compound (~50%) followed by palmitate. Afterwards, a shift in the LCFA pattern accumulation was noticed for both reactors. At periods with higher OMW concentrations (30-50 g COD L-1, 3-5 kg COD m-3 d-1) palmitate was the main LCFA accumulated with 69% at R1 and 54% at R2. For real oily wastewaters, a periodically batch period could be a practical solution to maintain low values of LCFA inside the reactor. The addition of a nitrogen source was essential to enhance the methane yield

IASB-Inverted Anaerobic Sludge Blanket reactor : background, history and development

Existing high rate anaerobic technology such as UASB, EGSB and IC reactors based on granular sludge is not robust when applied to industrial effluents with high lipids content. After discovering the potential of converting fat and long chain fatty acids to methane, the development of a compact high rate anaerobic reactor technology for the treatment of effluents of high lipid content was pursued. In this paper the fundamentals of anaerobic LCFA degradation are revised.the basic principles of the IASB technology are described and results of a pilot plant treating a slaughterhouse effluent are presented. An organic loading rate of 16 kg COD/m3.day was applied being 63% of FOG. Effluent VSS were around 500 mg/L COD, removal efficiency was consistently above 80% and excessive LCFA accumulation was prevented (<1 g COD-LCFA/gTS). The start-up of the first full scale reference of the IASB reactor located in a fish canning factory (A Poveira, Portugal) is described

The impact of the Lettinga Award 2004 on the anaerobic wastewater treatment sector in Portugal

Due to bad experiences in the past, anaerobic treatment got a bad name in Portugal. The Lettinga Award awarded to Madalena Alves in 2004 had a definite positive impact on the Portuguese anaerobic wastewater treatment sector. It initiated a vicious circle of research & development leading to the development of innovative anaerobic technology. Up to now it has resulted in an international patent, two national innovation prizes, one PhD grant, € 75,000 in cosubsidies for the pilot plant construction a and a company start-up (AMBISYS, S.A.). The media attention attached to this Award, promoted by the communication office of the University of Minho, resulted in an improved overall image of anaerobic treatment technology in Portugal

Development of a novel reactor for high-rate anaerobic treatment of LCFA containing wastewater

treatment. More than 2,000 full-scale installations are running worldwide (Van Lier, 2007) and mainly treat wastewaters containing readily degradable organic pollutants such as volatile fatty acids and carbohydrates. Lipids do not belong to this group, since their hydrolysis results in the production of long chain fatty acids (LCFA). Until recently these were considered toxic to anaerobic bacteria and a nuisance because they induce floatation of biomass (Hwu, 1997). Since the success of conventional anaerobic treatment systems is based on optimisation of biomass sedimentation, floatation leads to washout and subsequent process disruption. Therefore, lipids are normally removed from wastewater prior to anaerobic treatment using e.g. dissolved air floatation. Pereira et al. (2002) showed that lipids are not toxic and can be converted to biogas. As to prevent washout induced by LCFA adsorption, a sequential process including at least a feeding and reaction phase was proposed as the preferred technology for anaerobic LCFA removal from wastewater (Pereira et al., 2005). It was further postulated that the specific contact area between bacteria and LCFA should be maximised as to maximise LCFA adsorption and minimise mass transfer limitations. The sequential process was applied at la

Development of the Inverted anaerobic sludge blanket reactor: a novel technology for the treatment of industrial wastewater containing fat

Tese de doutoramento em Engenharia Química e BiológicaLipids are ubiquitous in industrial wastewater produced in the food industry, yet practically no biological treatment systems are available on the market that are capable of directly treating wastewater containing lipids. In general, lipids are considered a nuisance and are normally removed prior to biological treatment. Lipids are however compounds with a high calorific value and therefore highly interesting for conversion into biogas under anaerobic conditions. This thesis reports on the development of a high-rate anaerobic reactor capable of directly treating wastewater containing fat. The reactor’s technological basis for includes floatation as main sludge retention technique. Next to that, the specific contact surface between sludge and fat is maximised to prevent mass transfer limitation. Because fat degradation leads again to settlable sludge, a sedimentation step is incorporated in the form of a tilted plate separator (TPS). The settled sludge is then recycled and mixed up with raw wastewater to stimulate fat adsorption and sludge floatation. The sludge/raw wastewater mixture is subsequently injected into downers to induce reactor mixing and the break-up of floating sludge. Finally, to counteract foam formation, treated wastewater is sprayed in the head space. These considerations formed the basis of the Inverted Anaerobic Sludge Blanket (IASB) reactor. The IASB concept was tested using several lab-scale configurations and lead to an optimised 1.2 m3 pilot scale reactor. Its robustness and capacity for treating wastewater strongly fluctuating in quality while maintaining treatment efficiency was demonstrated during a one year pilot trial on slaughterhouse wastewater. Until an organic loading rate of 12 kg COD/m3/day, no problems were encountered in terms of COD removal. The TPS showed to be efficient in retaining solids inside the reactor. The spray flow rate, however, should not go through the TPS. The IASB technology is currently being scaled-up to industrial scale taking the pilot findings into account. A modular approach was chosen as to reduce investment costs associated to the technology. The IASB technological development further resulted in a novel separation technology called Sludge Lift Separator. Separator design was optimised using computational fluid dynamics. The technology is currently being tested at pilot scale

Health literacy among older adults is associated with their 10-years' cognitive functioning and decline - the Doetinchem Cohort Study.

Many older adults have low levels of health literacy which affects their ability to participate optimally in healthcare. It is unclear how cognitive decline contributes to health literacy. To study this, longitudinal data are needed. The aim of this study was therefore to assess the associations of cognitive functioning and 10-years' cognitive decline with health literacy in older adults

Health-related quality of life as measured with EQ-5D among populations with and without specific chronic conditions: A population-based survey in Shaanxi province, China

© 2013 Tan et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Introduction: The aim of this study was to examine health-related quality of life (HRQoL) as measured by EQ-5D and to investigate the influence of chronic conditions and other risk factors on HRQoL based on a distributed sample located in Shaanxi Province, China. Methods: A multi-stage stratified cluster sampling method was performed to select subjects. EQ-5D was employed to measure the HRQoL. The likelihood that individuals with selected chronic diseases would report any problem in the EQ-5D dimensions was calculated and tested relative to that of each of the two reference groups. Multivariable linear regression models were used to investigate factors associated with EQ VAS. Results: The most frequently reported problems involved pain/discomfort (8.8%) and anxiety/depression (7.6%). Nearly half of the respondents who reported problems in any of the five dimensions were chronic patients. Higher EQ VAS scores were associated with the male gender, higher level of education, employment, younger age, an urban area of residence, access to free medical service and higher levels of physical activity. Except for anemia, all the selected chronic diseases were indicative of a negative EQ VAS score. The three leading risk factors were cerebrovascular disease, cancer and mental disease. Increases in age, number of chronic conditions and frequency of physical activity were found to have a gradient effect. Conclusion: The results of the present work add to the volume of knowledge regarding population health status in this area, apart from the known health status using mortality and morbidity data. Medical, policy, social and individual attention should be given to the management of chronic diseases and improvement of HRQoL. Longitudinal studies must be performed to monitor changes in HRQoL and to permit evaluation of the outcomes of chronic disease intervention programs. © 2013 Tan et al.National Nature Science Foundation (No. 8107239

Perspectives of older women in the Netherlands: identifying motivators and barriers for healthy lifestyles and determinants of healthy aging

BACKGROUND: Women have a higher life expectancy than men but experience more years with physical disabilities in daily life at older ages, especially women with a migration background. This pinpoints older women as an important target group for strategies that stimulate healthy lifestyle, which benefits healthy aging. Our study investigates motivators and barriers for healthy lifestyles and perspectives on determinants of healthy aging of older women. This provides essential information for developing targeted strategies. METHODS: Data was collected by semi-structured digital interviews from February till June 2021. Women aged 55 years and older living in the Netherlands (n = 34) with a native Dutch (n = 24), Turkish (n = 6) or Moroccan (n = 4) migration background were included. Two main subjects were investigated: (1) motivators and barriers on their current lifestyles regarding smoking, alcohol consumption, physical activity, diet and sleep and (2) perspectives on determinants of healthy aging. Interviews were analyzed using Krueger's framework. RESULTS: Personal health was the most common motivator for a healthy lifestyle. In addition, peer pressure and being outdoors were specific motivators for physical activity. Bad weather conditions and personal dislike to be active were specific barriers. The social environment, personal preferences and personal belief to compensate with other healthy lifestyle behaviors were barriers for low alcohol consumption. Personal preferences (liking unhealthy food and not making time) were the main barriers for a healthy diet. Sleep was not perceived as a form of lifestyle behavior, but rather as a personal trait. Since there were no smokers, specific barriers were not mentioned. For Turkish-Dutch and Moroccan-Dutch women, additional barriers and motivators were culture and religion. These were strong motivators to abstain from alcohol consumption and smoking, but a barrier for a healthy diet. With regard to perspectives on determinants of healthy aging, positive views on aging and being physically active were perceived as most important. Women often wanted to increase their physical activity or healthy diet to stimulate healthy aging. Among Turkish-Dutch and Moroccan-Dutch women, healthy aging was also perceived as something in the hands of God. CONCLUSIONS: Although motivators and barriers for a healthy lifestyle and perspectives on healthy aging vary for distinct lifestyles, personal health is a common motivator across all lifestyles. Having a migration background added culture and religion as distinct barriers and motivations. Strategies to improve lifestyle among older women should therefore have a tailored, culture sensitive approach (if applicable) for distinct lifestyle factors

Study protocol of cost-effectiveness and cost-utility of a biopsychosocial multidisciplinary intervention in the evolution of non-specific sub-acute low back pain in the working population: cluster randomised trial.

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background: Low back pain (LBP), with high incidence and prevalence rate, is one of the most common reasons to consult the health system and is responsible for a significant amount of sick leave, leading to high health and social costs. The objective of the study is to assess the cost-effectiveness and cost-utility analysis of a multidisciplinary biopsychosocial educational group intervention (MBEGI) of non-specific sub-acute LBP in comparison with the usual care in the working population recruited in primary healthcare centres. Methods/design: The study design is a cost-effectiveness and cost-utility analysis of a MBEGI in comparison with the usual care of non-specific sub-acute LBP.Measures on effectiveness and costs of both interventions will be obtained from a cluster randomised controlled clinical trial carried out in 38 Catalan primary health care centres, enrolling 932 patients between 18 and 65 years old with a diagnosis of non-specific sub-acute LBP. Effectiveness measures are: pharmaceutical treatments, work sick leave (% and duration in days), Roland Morris disability, McGill pain intensity, Fear Avoidance Beliefs (FAB) and Golberg Questionnaires. Utility measures will be calculated from the SF-12. The analysis will be performed from a social perspective. The temporal horizon is at 3 months (change to chronic LBP) and 12 months (evaluate the outcomes at long term. Assessment of outcomes will be blinded and will follow the intention-to-treat principle. Discussion: We hope to demonstrate the cost-effectiveness and cost-utility of MBEGI, see an improvement in the patients' quality of life, achieve a reduction in the duration of episodes and the chronicity of non-specific low back pain, and be able to report a decrease in the social costs. If the intervention is cost-effectiveness and cost-utility, it could be applied to Primary Health Care Centres. Trial registration: ISRCTN: ISRCTN5871969