An integrated system for agricultural wastewater treatment

1995 ◽  
Vol 32 (12) ◽  
pp. 165-171
Author(s):  
N. Rovirosa ◽  
E. Sánchez ◽  
F. Benítez ◽  
L. Travieso ◽  
A. Pellón

The treatment of agroindustrial wastewaters gives the possibility of noxious pollutant removal which otherwise would deteriorate the ecosystem even more. The construction and start-up of Integrated Systems for the treatment of such wastes allow the reuse of the treated effluents, with the consequent production of useful by-products. Biological processes for the adequate treatment of 300 m3/day of mixed animal and human wastewaters allow also the production of 1200 m3/day of biogas as an energy supplier and a source of CO2 for microalgae culture in a High Rate Algal Pond. On the other hand, it can be possible to recover the digested sludge as biofertilizer and low grade water useful for crop irrigation. The proposed Integrated System also provides the recovery of 8.3 g/m2/d of algal biomass suitable for animal consumption and the removal of an important amount of noxious pollutants with an average efficiency of 80–98% (COD basis).

2004 ◽  
Vol 50 (8) ◽  
pp. 65-72 ◽  
Author(s):  
Y.Q. Zhao ◽  
G. Sun ◽  
C. Lafferty ◽  
S.J. Allen

A gravel-based tidal flow reed bed system was operated with three different strategies in order to investigate its optimal performance for the treatment of a high strength agricultural wastewater. According to the three strategies, individual reed beds were saturated and unsaturated with the wastewater for different periods while reasonably stable hydraulic and organic loadings were maintained. Experimental results demonstrated that the system produced the highest pollutant removal efficiencies with a relatively short saturated period and long unsaturated period, highlighting the importance of oxygen transfer into reed bed matrices during the treatment. Significant removals of some major organic and inorganic pollutants were achieved under all three operational conditions. Nitrification was not the major route of ammoniacal-nitrogen removal when the system was under high organic loading. Due to the filtration of suspended solids and the accumulation of biomass, gradual clogging of the reed bed matrices took place, which caused concerns over the long-term efficiency of the tidal flow system.


2021 ◽  
pp. 1-10 ◽  
Author(s):  
Noor Hamdan ◽  
Hugues Duffau

OBJECTIVE Maximal safe resection is the first treatment in diffuse low-grade glioma (DLGG). Due to frequent tumor recurrence, a second surgery has already been reported, with favorable results. This study assesses the feasibility and functional and oncological outcomes of a third surgery in recurrent DLGG. METHODS Patients with DLGG who underwent a third functional-based resection using awake mapping were consecutively selected. They were classified into group 1 in cases of slow tumor regrowth or group 2 if a radiological enhancement occurred during follow-up. All data regarding clinicoradiological features, histomolecular results, oncological treatment, and survival were collected. RESULTS Thirty-one patients were included, with a median age of 32 years. There were 20 astrocytomas and 11 oligodendrogliomas in these patients. Twenty-one patients had medical oncological treatment before the third surgery, consisting of chemotherapy in 19 cases and radiotherapy in 8 cases. No neurological deficit persisted after the third resection except mild missing words in 1 patient, with 84.6% of the patients returning to work. The median follow-up duration was 13.1 ± 3.4 years since diagnosis, and 3.1 ± 2.9 years since the third surgery. The survival rates at 7 and 10 years were 100% and 89.7%, respectively, with an estimated median overall survival of 17.8 years since diagnosis. A comparison between the groups showed that the Karnofsky Performance Scale score dropped below 80 earlier in group 2 (14.3 vs 17.1 years, p = 0.01). Median residual tumor volume at the third surgery was smaller (2.8 vs 14.4 cm3, p = 0.003) with a greater extent of resection (89% vs 70%, p = 0.003) in group 1. CONCLUSIONS This is the first consecutive series showing evidence that, in select patients with progressive DLGG, a third functional-based surgery can be achieved using awake mapping with low neurological risk and a high rate of total resection, especially when reoperation is performed before malignant transformation.


2015 ◽  
Vol 7 ◽  
pp. e2015044 ◽  
Author(s):  
Sara Lo Menzo ◽  
Giulia La Martire ◽  
Giancarlo Ceccarelli ◽  
Mario Venditti

Bloodstream infections (BSI) are an important cause of morbidity and mortality in onco-hematologic patients. The Gram-negative etiology was the main responsible of the febrile neutropenia in the sixties and its impact declined due to the use of fluoroquinolone prophylaxis; this situation was followed by the gradual emergence of Gram-positive bacteria also following of the increased use of intravascular devices and the introduction of new chemotherapeutic strategies. In the last decade the Gram-negative etiology is raising again because of the emergence of resistant strains that make questionable the usefulness of currentstrategies for prophylaxis and empirical treatment. Gram-negative BSI attributable mortality is relevant and the appropriate empirical treatment significantly improves the prognosis; on the other hand the delayed adequate treatment of Gram-positive BSI does not seem to have an high impact on survival. The clinician has to be aware of the epidemiology of his institution and of colonizations of his patients in order to choose the most appropriate empiric therapy. Ina setting of high endemicity of multidrug-resistant infections, even the choice of a targeted therapy can be a challenge, often requiring strategies based on off-label prescriptions and low grade evidences.In this review we summarize the current evidences for the best targeted therapies for difficult to treat bacteria BSIs and future perspectives in this topic. We also provide a flow chart for a rational approach to the empirical treatment of febrile neutropenia in a multidrug resistant high prevalence setting.


1992 ◽  
Vol 26 (3-4) ◽  
pp. 601-605 ◽  
Author(s):  
H.-S. Shin ◽  
K.-H. Lim ◽  
H.-S. Park

Aerobic upflow sludge blanket(AUSB) process is a new biological wastewater treatment method applying the concept of the self-immobilization to activated sludge. Two sets of AUSB system with different mixing velocities of 3 rpm(R1) and 6 rpm(R2) were operated for high-rate treatment of synthetic wastewater. The COD removal efficiency in R2 was higher than R1 at the same loading rate up to 7 kg/m3·day. However, in R1, the sludge bulking was observed at the end of the experiment. The chocolate colored granules were formed about 5 days after the start-up. The morphological study on the granular sludge consortia was made with both scanning electron and optical microscopes. The granules were 0.5-2.5 mm in diameter and mainly consisted of bacteria with pili-like appendages and filamentous bacteria, which were thought to be Sphaerotilus natans and Beggiatoa. In R1, the long multicellular filaments causing bulking were prevalent in the granule, while in R2 overgrowth of filamentous bacteria was prevented with appropriate shear stress resulting in higher MLSS density. Experimental results indicated that granulation could be controlled by physical stress on granular sludge.


2020 ◽  
Vol 307 ◽  
pp. 123195 ◽  
Author(s):  
Bao-Shan Xing ◽  
Sifan Cao ◽  
Yule Han ◽  
Junwei Wen ◽  
Kaidi Zhang ◽  
...  
Keyword(s):  

1990 ◽  
Vol 22 (1-2) ◽  
pp. 17-24 ◽  
Author(s):  
G. Albagnac

Recognition of the advantages of anaerobic wastewater treatment induced the development of high rate processes, i.e. reactors designed to allow an efficient treatment of even diluted streams. The performance of these advanced reactors is mainly dependent on the retention within the reactor of high bacterial concentrations. The prevailing mechanism is either the formation of bacterial aggregates with good settling characteristics, the development of methanogenic biolayers at the surface of inert carriers or both. During the past decade information on the biology of methanogenic ecosystems became available at an increasing rate. From a practical point of view it can be stated that the biological conversion of organic compounds to methane is reasonably well understood. However the current knowledge on the aggregation and adhesion of methanogenic consortia remains very limited. In most cases reactor start-up procedures are rather long and appear to be more empirical than rational. This paper is a brief presentation on the current knowledge of methanogenic aggregates and biofilms. The fundamental aspects of bacterial adhesion and the modelling of anaerobic biofilms growth are presented elsewhere.


1996 ◽  
Vol 14 (7) ◽  
pp. 1974-1981 ◽  
Author(s):  
M S Kaminski ◽  
K R Zasadny ◽  
I R Francis ◽  
M C Fenner ◽  
C W Ross ◽  
...  

PURPOSE The CD20 B-lymphocyte surface antigen expressed by B-cell lymphomas is an attractive target for radioimmunotherapy, treatment using radiolabeled antibodies. We conducted a phase I dose-escalation trial to assess the toxicity, tumor targeting, and efficacy of nonmyeloablative doses of an anti-CD20 monoclonal antibody (anti-B1) labeled with iodine-131 (131I) in 34 patients with B-cell lymphoma who had failed chemotherapy. PATIENTS AND METHODS Patients were first given tracelabeled doses of 131I-labeled anti-B1 (15 to 20 mg, 5 mCi) to assess radiolabeled antibody biodistribution, and then a radioimmunotherapeutic dose (15 to 20 mg) labeled with a quantity of 131I that would deliver a specified centigray dose of whole-body radiation predicted by the tracer dose. Whole-body radiation doses were escalated from 25 to 85 cGy in sequential groups of patients in 10-cGy increments. To evaluate if radiolabeled antibody biodistribution could be optimized, initial patients were given one or two additional tracer doses on successive weeks, each dose preceded by an infusion of 135 mg of unlabeled anti-B1 one week and 685 mg the next. The unlabeled antibody dose resulting in the most optimal tracer biodistribution was also given before the radioimmunotherapeutic dose. Later patients were given a single tracer dose and radioimmunotherapeutic dose preceded by infusion of 685 mg of unlabeled anti-B1. RESULTS Treatment was well tolerated. Hematologic toxicity was dose-limiting, and 75 cGy was established as the maximally tolerated whole-body radiation dose. Twenty-eight patients received radioimmunotherapeutic doses of 34 to 161 mCi, resulting in complete remission in 14 patients and a partial response in eight. All 13 patients with low-grade lymphoma responded, and 10 achieved a complete remission. Six of eight patients with transformed lymphoma responded. Thirteen of 19 patients whose disease was resistant to their last course of chemotherapy and all patients with chemotherapy-sensitive disease responded. The median duration of complete remission exceeds 16.5 months. Six patients remain in complete remission 16 to 31 months after treatment. CONCLUSION Nonmyeloablative radioimmunotherapy with 131I-anti-B1 is associated with a high rate of durable remissions in patients with B-cell lymphoma refractory to chemotherapy.


2016 ◽  
Vol 73 (12) ◽  
pp. 2858-2867 ◽  
Author(s):  
N. Ramdani ◽  
A. Lousdad ◽  
A. Tilmatine ◽  
S. Nemmich

Abstract Current research reveals that the oxidation by ozone is considered as an effective solution and offers irrefutable advantages in wastewater treatment. It is also well known that ozone is used to treat different types of water due to its effectiveness in water purification and for its oxidation potential. This process of ozonation is becoming progressively an alternative technology and is inscribed in a sustainable development perspective in Algeria. In this regards, the present paper investigates the wastewater treatment process by ozone produced by dielectric barrier discharge (DBD) under high potential. Three (DBD) ozone generators of cylindrical form have been used, at a laboratory scale, for treating collected samples from the wastewater treatment plant (WWTP) of the city of Sidi-Bel-Abbes located in the west of Algeria. Our experimental results reveal the efficiency of this type of treatment on the basis of the physicochemical analysis (pH, turbidity, chemical oxygen demand, biological oxygen demand, heavy metals) and microbial analysis downstream of the WWTP, which showed a high rate of elimination of all the parameters.


2020 ◽  
Vol 21 (14) ◽  
pp. 4929
Author(s):  
Anna De Filippis ◽  
Hammad Ullah ◽  
Alessandra Baldi ◽  
Marco Dacrema ◽  
Cristina Esposito ◽  
...  

Gastrointestinal (GI) diseases, which include gastrointestinal reflux disease, gastric ulceration, inflammatory bowel disease, and other functional GI disorders, have become prevalent in a large part of the world population. Metabolic syndrome (MS) is cluster of disorders including obesity, hyperglycemia, hyperlipidemia, and hypertension, and is associated with high rate of morbidity and mortality. Gut dysbiosis is one of the contributing factors to the pathogenesis of both GI disorder and MS, and restoration of normal flora can provide a potential protective approach in both these conditions. Bioactive dietary components are known to play a significant role in the maintenance of health and wellness, as they have the potential to modify risk factors for a large number of serious disorders. Different classes of functional dietary components, such as dietary fibers, probiotics, prebiotics, polyunsaturated fatty acids, polyphenols, and spices, possess positive impacts on human health and can be useful as alternative treatments for GI disorders and metabolic dysregulation, as they can modify the risk factors associated with these pathologies. Their regular intake in sufficient amounts also aids in the restoration of normal intestinal flora, resulting in positive regulation of insulin signaling, metabolic pathways and immune responses, and reduction of low-grade chronic inflammation. This review is designed to focus on the health benefits of bioactive dietary components, with the aim of preventing the development or halting the progression of GI disorders and MS through an improvement of the most important risk factors including gut dysbiosis.


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