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1.
Environ Pollut ; 316(Pt 2): 120667, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36395914

ABSTRACT

Hydrothermal liquefaction (HTL) is identified as a promising thermochemical technique to recover biofuels and bioenergy from waste biomass containing low energy and high moisture content. The wastewater generated during the HTL process (HTWW) are rich in nutrients and organics. The release of the nutrients and organics enriched HTWW would not only contaminate the water bodies but also lead to the loss of valued bioenergy sources, especially in the present time of the energy crisis. Thus, biotechnological as well as physicochemical treatment of HTWW for simultaneous extraction of valuable resources along with reduction in polluting substances has gained significant attention in recent times. Therefore, the treatment of wastewater generated during the HTL of biomass for reduced environmental emission and possible bioenergy recovery is highlighted in this paper. Various technologies for treatment and valorisation of HTWW are reviewed, including anaerobic digestion, microbial fuel cells (MFC), microbial electrolysis cell (MEC), and supercritical water gasification (SCWG). This review paper illustrates that the characteristics of biomass play a pivotal role in the selection process of appropriate technology for the treatment of HTWW. Several HTWW treatment technologies are weighed in terms of their benefits and drawbacks and are thoroughly examined. The integration of these technologies is also discussed. Overall, this study suggests that integrating different methods, techno-economic analysis, and nutrient recovery approaches would be advantageous to researchers in finding way for maximising HTWW valorisation along with reduced environmental pollution.


Subject(s)
Industry , Wastewater , Biomass , Technology , Water
2.
Biomass Convers Biorefin ; 12(3): 949-966, 2022.
Article in English | MEDLINE | ID: mdl-33520587

ABSTRACT

The circular economy is at the core of sustainable development. The generation of biogas from the massive quantity of agricultural waste biomass is one of the critical drivers of the circular economy. Biogas has enormous renewable energy potential and has multitudes of applications in today's energy-intensive society. Oil cakes, a known Agri-waste, are the by-product of oil processing, and are rich in nutrients. The edible oil cakes mostly have been used as a cattle feed; however, non-edible oil cakes do not find many applications. Their production is continuously escalating as non-edible oils are increasingly used in biodiesel production. Recently, there is a lot of emphasis on biogas production from these oil cakes. This paper reviews in detail biogas production from both edible and non-edible oil cakes. Chemical composition and various other applications of the cakes are also reviewed in brief. The survey illustrates that multiple parameters such as inoculum sources, co-digestion and reactor design affect the biogas production. All those factors, along with biogas upgrading and the economy of the process, are reviewed. Finally, future research opportunities are suggested to improve the viability of the biogas production from oil cakes.

3.
Article in English | MEDLINE | ID: mdl-27226897

ABSTRACT

BACKGROUND: Phenol is one of the most versatile and important organic compound. It is also a growing concern as water pollutants due to its high persistence and toxicity. Removal of Phenol from wastewaters was investigated using a novel nanoparticle adsorption and nanofiltration technique named as Nanoparticle Assisted Nano Filtration (NANF). METHODS: The nanoparticle used for NANF study were silver nanoparticles and synthesized to three distinct average particle sizes of 10 nm, 40 nm and 70 nm. The effect of nanoparticle size, their concentrations and their tri and diparticle combinations upon phenol removal were studied. RESULTS: Total surface areas (TSA) for various particle size and concentrations have been calculated and the highest was 4710 × 10(12 )nm(2 )for 10 nm particles and 180 ppm concentration while the lowest was for 2461 × 10(11) for 70 nm and 60 ppm concentrations. Tri and diparticle studies showed more phenol removal % than that of their individual particles, particularly for using small particles on large membrane pore size and large particles at low concentrations. These results have also been confirmed with COD and toxicity removal studies. CONCLUSIONS: The combination of nanoparticles adsorption and nanofiltration results in high phenol removal and mineralization, leading to the conclusion that NANF has very high potential for treating toxic chemical wastewaters.

4.
Bioresour Technol ; 196: 707-11, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26238237

ABSTRACT

This study details the application of naturally available biogenic substrates (NABS) in microbial degradation of 2-chlorophenol (CP). Jatropha deoiled cakes (JDC) and Karanja deoiled cakes (KDC) are used as NABS. The potential of NABS is compared with standard biogenic substrate, glucose. The study was carried out with both acclimatized mixed culture and pure culture, Pseudomonas putida. Microbial activity of the culture was monitored by measuring reduction in chlorophenol concentration, COD, toxicity and Cl(-) ions evolution. The study was carried out for a total of 42days. It was observed that culture having NABS has shown similar chlorophenol reduction but higher COD and toxicity reduction. Amongst NABS, Jatropha deoiled cake (JDC) has shown superior results of 71% COD reduction compared to glucose and KDC. This study is one of the first kind illustrating the potential of these substrates in removing toxic chemicals from wastewaters.


Subject(s)
Biodegradation, Environmental , Bioreactors/microbiology , Chlorophenols , Pseudomonas putida/metabolism , Chlorophenols/chemistry , Chlorophenols/isolation & purification , Chlorophenols/metabolism , Jatropha/chemistry
5.
Environ Sci Pollut Res Int ; 22(21): 16814-29, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26099599

ABSTRACT

Air pollution is one of the major global hazards and industries have been one of its major contributors. This paper primarily focuses on analyzing the dispersion characteristics of buoyant plumes of the pollutant released from a multi-flue vertical stack into a variable temperature gradient atmosphere (α) in a constant-velocity cross wind using two stack configurations-inline and parallel. The study is conducted for different Froude numbers, Fr = 12.64, 9.55, and 8.27. The atmospheric temperature gradients considered for the study are 0, +1, +1.5, and +2 K/100 m. The numerical study is done using the commercial computational fluid dynamics (CFD) code FLUENT. The effects of stack configuration, α, and Fr on the plume characteristics are presented. It is observed that the plume rises higher and disperses over a larger area with the inline configuration due to better mixing and shielding effect. With higher α, it is seen that the plume rises initially and then descends due to variation of the buoyant force. The plume rise initially is strongly influenced by the momentum of the jet, and as it moves downstream, it is influenced by the cooling rate of the plume. Furthermore, the plume rises higher and disperses over a larger area with a decrease in Fr.


Subject(s)
Air Pollutants/chemistry , Atmosphere/chemistry , Models, Theoretical , Temperature , Air Pollutants/analysis , Wind
6.
Acta Gastroenterol Belg ; 75(1): 42-4, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22567746

ABSTRACT

Chronic intussusception is defined as intussusception with a history of more than 14 days and is generally associated with a predisposing factor. We are reporting a rare case of chronic intussusception due to Non Hodgkin lymphoma of ileum, appendix, caecum and ascending colon presented as acute intestinal obstruction in emergency. Chronic Intussusception is rare in childhood due to Non Hodgkin lymphoma. A five year male child presented with fever, pain abdomen, vomiting, diarrhoea and mass in right flank. Ultrasonography of the abdomen revealed a mass in ileao-caecal region with chronic intussusception which was confirmed on surgery. X ray of the abdomen showed dilated bowel loops. It is very difficult to make diagnosis of intestinal lymphoma on pre-operative investigations. Patient presented with obstruction should be explored as surgery is the treatment of the choice. Diagnosis can be confirmed by histopathologically. In conclusion, a high index of suspicion and appropriate investigations (USS, Barium enema and CT scan) can result in prompt diagnosis. In majority of children the diagnosis is made at laparotomy and surgery plays a pivotal role in the management.


Subject(s)
Intestinal Neoplasms/complications , Intussusception/etiology , Lymphoma, Non-Hodgkin/complications , Child, Preschool , Chronic Disease , Humans , Intussusception/diagnosis , Male
7.
J Photochem Photobiol B ; 98(1): 1-6, 2010 Jan 21.
Article in English | MEDLINE | ID: mdl-19914843

ABSTRACT

In this work, the performance of integrated photocatalytic and biological treatment was studied for the degradation of 4-chlorophenol (MCP) present in wastewaters. Photocatalysis was used as a pre-treatment to biological degradation. Pollutant removal efficiency was quantified using MCP removal and total organic carbon (TOC) removal. Both photocatalytic as well as biological treatments were carried out in batch reactors, using TiO(2) as the photocatalyst. The inoculum for biological experiments was obtained from paper mill effluent treatment plant and was developed through a process of selection and acclimatization. Effect of TiO(2) concentration on the photocatalytic degradation of MCP was studied along with the effect of the duration of photochemical oxidation and glucose concentrations (0 g/L, 1 g/L and 2 g/L) on the biodegradation of MCP. Integrated biological and photochemical degradation was found to be more effective in treating MCP, especially at higher concentrations (400 mg/L). An initial MCP concentration of 400 mg/L required 96 h for complete mineralization when treated with the process combination, whereas the treatment went on up to 264 h when biodegradation alone was employed.


Subject(s)
Chlorophenols/chemistry , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/chemistry , Biodegradation, Environmental , Bioreactors , Catalysis , Chlorophenols/metabolism , Chlorophenols/radiation effects , Kinetics , Oxidation-Reduction , Titanium/chemistry , Ultraviolet Rays , Water Pollutants, Chemical/metabolism , Water Pollutants, Chemical/radiation effects
8.
N Am J Med Sci ; 2(8): 392-4, 2010 Aug.
Article in English | MEDLINE | ID: mdl-22737679

ABSTRACT

CONTEXT: Superior mesenteric artery syndrome is a life- threatening upper gastrointestinal disorder due to compression of duodenum as it poses a difficult diagnostic dilemma. Third part of duodenum is in fixed compartment bounded anteriorly by the root of mesentery and superior mesentery artery and posteriorly by the aorta and lumbar spine. On barium contrast study and abdominal computerized tomography (CT) showed the dilatation of second part of duodenum and compression of the third part of duodenum between aorta and superior mesentery artery. CASE REPORT: A 22 year young asthenic man admitted with the complaint of recurrent abdominal pain, epigastric fullness, and vomiting and weight loss. Abdominal examination revealed epigastric fullness and hyper peristaltic bowel sounds. Upper gastrointestinal barium study showed a dilated stomach with dilated second part of the duodenum and cut off at the third part of duodenum with no intrinsic mucosal abnormalities. There was no relief of obstruction in the left lateral decubitus or prone position. Conservative treatment was tried for one month but failed. Intra-operative findings confirmed the extrinsic obstruction of third part of duodenum with distension of 2(nd) part. A retrocolic duodenojejunostomy, side to side anastomosis done. In post-operative follow up, patient was symptom free. CONCLUSION: Superior mesentery artery syndrome is a life threatening disease. It should be treated as soon as possible. Conservative trial can be given but Surgery is the treatment of the choice.

9.
Water Res ; 38(19): 4247-61, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15491671

ABSTRACT

Sonochemical degradation which combines destruction of the target compounds by free radical reaction and thermal cleavage is one of the recent advanced oxidation processes (AOP) and proven to be effective for removing low concentration organic pollutants from aqueous streams. This work describes the degradation of several organic compounds of varying volatility in aqueous solution in two types of ultrasonic reactors. The process variables studied include initial concentration of the organics, temperature, and type of saturated gas. The effects of additional oxidant and electrolyte were also examined. A kinetic model was tested to determine its ability to predict the degradation rate constant of different volatile organic compounds at different initial conditions. A figure of merit for the electrical energy consumption for the two types of ultrasonic reactors is also presented.


Subject(s)
Models, Theoretical , Water Pollutants/isolation & purification , Water Purification/methods , Forecasting , Kinetics , Organic Chemicals/isolation & purification , Oxidation-Reduction , Temperature , Volatilization
11.
Asian Cardiovasc Thorac Ann ; 11(4): 285-8, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14681085

ABSTRACT

The benefit and safety of off-pump coronary artery bypass surgery in patients with unstable angina was assessed retrospectively. From February 1996 to October 2001, 5,306 patients underwent multivessel off-pump coronary artery bypass, of whom 920 (17%) had unstable angina. In these 920 patients, ejection fractions ranged from 15% to 70%, 203 (22%) had an ejection fraction of 20%-35%, and 11 (1%) had an ejection fraction < 20%. Triple-vessel disease was present in 625 patients. Preoperative intraaortic balloon pump support was used in 28 patients. Operative approaches included mid sternotomy (86%), lower partial sternotomy (9%), and left anterior thoracotomy (2%). The number of grafts ranged from 1 to 5 with a mean of 2.43 +/- 0.86, and 92.3% of patients received a left internal mammary artery graft. Twenty-two patients need intraoperative intraaortic balloon pumping. Ten patients (1%) suffered perioperative myocardial infarction. The mean hospital stay was 7.8 +/- 4.3 days. Hospital mortality was 2/920 (0.22%). Intraaortic balloon pumping was helpful in these cases of unstable angina refractory to medical therapy. Off-pump coronary artery surgery was found to be safe and beneficial in these patients.


Subject(s)
Angina, Unstable/surgery , Cardiopulmonary Bypass/methods , Coronary Artery Bypass/methods , Adult , Aged , Angina, Unstable/physiopathology , Female , Humans , Male , Middle Aged , Retrospective Studies , Stroke Volume/physiology , Treatment Outcome
12.
Asian Cardiovasc Thorac Ann ; 11(3): 258-60, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14514560

ABSTRACT

A 29-year-old man with atypical chest pain for 3 years and exertional angina for 3 months was found to have a large homogenous mass in the apicolateral area of the left ventricle. The mass, weighing 78 g, was excised successfully and identified as a fibroma.


Subject(s)
Cardiac Surgical Procedures/methods , Chest Pain/etiology , Fibroma/surgery , Heart Neoplasms/surgery , Adult , Fibroma/complications , Fibroma/diagnosis , Heart Neoplasms/complications , Heart Neoplasms/diagnosis , Heart Ventricles , Humans , Magnetic Resonance Imaging , Male
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