Co-Pyrolysis of Polyethylene Plastic and Cellulose as Models for Medical Waste in Supercritical Water

2014 ◽  
Vol 1010-1012 ◽  
pp. 952-955 ◽  
Author(s):  
Yan Meng Gong ◽  
Shu Zhong Wang ◽  
Xing Ying Tang
Keyword(s):  
Organic Matter ◽  
Reaction Time ◽  
Supercritical Water ◽  
Time Pressure ◽  
Batch Reactor ◽  
Medical Waste ◽  
Oil Yield ◽  
Mass Ratio ◽  
Gaseous Products ◽  
Gasification Efficiency

Co-pyrolysis of polyethylene plastic and cellulose as models for medical waste had been studied on a supercritical water batch reactor. The results show that temperature, reaction time, pressure and the mass ratio of water to organic matter have some degree impact on the conversion rate, oil yield and gasification efficiency. Conversion and gasification efficiency reached the maximum values at 440 °C. The content of H2 in the gaseous products rose significantly between 25 MPa~27 MPa. As reaction time increased, conversion and gasification efficiency increased, but oil yield decreased. The composition of gaseous products was affected greatly by the mass ratio of water to organic matter. Adding K2CO3 and Ca (OH)2 as catalyst, the reaction was promoted obviously.

scholarly journals Synthesis of silver nanoparticles using supercritical water

2018 ◽  
pp. 22-25
Author(s):  
Buyankhishig B ◽  
Narandalai B ◽  
Enkhtuul S
Keyword(s):  
Particle Size ◽  
Silver Nanoparticles ◽  
Electron Microscope ◽  
Reaction Time ◽  
Supercritical Water ◽  
Silver Salt ◽  
Activated Carbons ◽  
Batch Reactor ◽  
Acetate Solution ◽  
Silver Acetate

Supercritical water (SCW) technology is a relatively novel and green method compared with others for the synthesize of metal nanoparticles. It is considered one of the most suitable methods for loading nanoparticles in surface of porous materials due to the water in supercritical conditions has a high diffusivity, well dispersive and it has a same carrier characteristic as like a gas. Silver nanoparticles and silver loaded activated carbons were synthesized using silver acetate solution under supercritical water condition at 4000C and 31.15 MPa in a batch reactor. This study was investigated effect of operational parameters on the particle size of silver nanoparticles in particularly the concen-tration of silver salt solution and the reaction time. The experiments were carried out to test the silver salt concentra-tion at 0.01 M, 0.02 M, 0.05M, and the reaction time of 15 and 30 minutes. When the silver acetate concentration and reaction time increased agglomerations of silver particles were observed on the surface of activated carbons. The structure, morphology and particle size of synthesized products were determined by X-ray diffraction (XRD), Scan-ning electron microscope (SEM) and Transmission electron microscope (TEM). Суперкртитик усан орчинд мөнгөний нанопартиклыг гарган авах Хураангуй: Суперкритик усны арга нь металлын нанопартикл гарган авах бусад аргуудтай харьцуулахад харьцангуй шинэ арга юм. Суперкритик нөхцөл дахь ус нь диффузийн коэффициент өндөртэй, тархалт сайтай, хийтэй адил зөөж тээвэрлэх шинж чанар үзүүлдэг тул сүвэрхэг материал дээр нанопартикл үүсгэхэд тохиромжтой аргуудын нэг гэж үздэг. Мөнгөний нанопартикл болон идэвхжүүлсэн нүүрсэн дээр суулгасан мөнгөний нанопартиклыг суперкритик усны аргаар мөнгөний давсны усан уусмал хэрэглэн гарган авсан. Мөнгөний нанопартиклыг гарган авахад нөлөөлөх гол хүчин зүйлүүдэд хамаарах мөнгөний давсны уусмалын концентрац болон урвал явагдах хугацааны нөлөөг судалсан бөгөөд концентрацыг 0.01 М, 0.02 М ба 0.05 М, харин урвал явагдах хугацааг 15 ба 30 минут гэсэн нөхцөлүүдэд туршилтыг явуулсан. Урвал явагдах хугацаа болон мөнгөний давсны уусмалын концентрац ихсэхэд үүссэн мөнгөний жижиг хэсгүүдийн бөөгнөрөл илүү нэмэгдэж байсан. Гарган авсан материалуудын талст бүтэц, түүний хэмжээ болон морфологийн шинж чанарыг рентген дифрактометр (XRD), сканнинг электрон микроскоп (SEM) болон нэвтрүүлэлтийн электрон микроскоп (TEM) ашиглан тодорхойлсон. Түлхүүр үг: Суперкритик ус, мөнгөний нанопартикл, урвал явагдах хугацаа, уусмалын концентрац.

scholarly journals Liquefaction performances of bread crusts in subcritical water

2020 ◽  
Vol 155 ◽  
pp. 01010
Author(s):  
Yuzhen Wang ◽  
Zhuan Liu ◽  
Changqing Fang ◽  
Zeyu Zhang ◽  
Li Xie
Keyword(s):  
Reaction Time ◽  
Subcritical Water ◽  
Batch Reactor ◽  
Jet Fuel ◽  
Oil Yield ◽  
Point Distribution ◽  
Bio Oil ◽  
Ft Ir ◽  
Ir Analysis ◽  
Increasing Temperature

Hydrothermal liquefaction of bread crusts in subcritical water were performed in a micro-batch reactor. The influences of temperature (300 – 360 °C) and residence time (10-30 min) on bio-oil yield, boiling point distribution and functional groups in bio-oil were investigated. The results showed that bio-oil yield increased with increasing temperature and reaction time. Maximum bio-oil yield of 22.69wt% was obtained at 360 °C, 30min. The longer reaction time promoted the degradation of diesel to jet fuel and naphtha. The naphtha (C7-10) and jet fuel (C11-C15) increased to 29.9%, 51.82% at 30min from 20.49% and 36.14%, respectively. FT-IR analysis showed that esters, ketones, amides, acids and aldehydes were present in the bio-oil.

Reforming of Glycerol into Bio-Crude: A Parametric Study

2013 ◽  
Vol 11 (1) ◽  
pp. 69-81 ◽  
Author(s):  
Matthew Tymchyshyn ◽  
Zhongshun Yuan ◽  
Chunbao (Charles) Xu
Keyword(s):  
Reaction Time ◽  
Reaction Temperature ◽  
Hydrogen Pressure ◽  
Zeolite Catalyst ◽  
Water Soluble ◽  
Oil Yield ◽  
Gaseous Products ◽  
Bio Oil ◽  
Negative Effect ◽  
Initial Hydrogen Pressure

Abstract The reforming of glycerol was investigated using a micro-reactor in the presence of MoCoP/zeolite catalyst. The parameters which were investigated include initial hydrogen pressure, reaction temperature, residence time, and feedstock concentration. The liquid products were separated into water-soluble components and bio-oil by liquid-liquid extraction with water and ethyl acetate. The bio-oil, gaseous products, char, and unreacted glycerol were quantified relative to the initial mass of glycerol feed. The composition of the bio-oil was determined by GC/MS. The optimum conditions for the reforming of glycerol into bio-crude in the presence of MoCoP/zeolite catalyst were found to be: 300°C reaction temperature, 5 MPa initial hydrogen pressure, 60 min reaction time, and 100% glycerol feed. While dilution of the glycerol feedstock with water had a negative effect on bio-oil yield, reforming of pure glycerol produced the highest bio-oil yield (40 wt.% at 300°C, 1 h, and 5 MPa H2). The amount of char deposited on the catalyst decreased with extended reaction time, increased reaction temperature, and elevated initial hydrogen pressure.

scholarly journals Gasification of Biomass in Supercritical Water, Challenges for the Process Design—Lessons Learned from the Operation Experience of the First Dedicated Pilot Plant

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 455
Author(s):  
Nikolaos Boukis ◽  
I. Katharina Stoll
Keyword(s):  
Organic Matter ◽  
Supercritical Water ◽  
Process Design ◽  
Pilot Plant ◽  
Lessons Learned ◽  
Present Contribution ◽  
Flow Process ◽  
Combustible Gas ◽  
Supercritical Water Gasification ◽  
Robust Process

Gasification of organic matter under the conditions of supercritical water (T > 374 °C, p > 221 bar) is an allothermal, continuous flow process suitable to convert materials with high moisture content (<20 wt.% dry matter) into a combustible gas. The gasification of organic matter with water as a solvent offers several benefits, particularly the omission of an energy-intensive drying process. The reactions are fast, and mean residence times inside the reactor are consequently low (less than 5 min). However, there are still various challenges to be met. The combination of high temperature and pressure and the low concentration of organic matter require a robust process design. Additionally, the low value of the feed and the product predestinate the process for decentralized applications, which is a challenge for the economics of an application. The present contribution summarizes the experience gained during more than 10 years of operation of the first dedicated pilot plant for supercritical water gasification of biomass. The emphasis lies on highlighting the challenges in process design. In addition to some fundamental results gained from comparable laboratory plants, selected experimental results of the pilot plant “VERENA” (acronym for the German expression “experimental facility for the energetic exploitation of agricultural matter”) are presented.

Optimization and statistical analysis of sono-Fenton treated wastewater of food industry using reactor by response surface method

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Vijay A. Juwar ◽  
Ajit P. Rathod
Keyword(s):  
Reaction Time ◽  
Response Surface ◽  
Food Industry ◽  
Batch Reactor ◽  
Oxygen Demand ◽  
Volume Ratio ◽  
Cod Removal ◽  
Treated Wastewater ◽  
Experimental Result ◽  
Molar Ratio

Abstract The present study deals with the treatment of complex waste (WW) treated for removal of chemical oxygen demand (COD) of the food industry by a sono-Fenton process using a batch reactor. The response surface methodology (RSM) was employed to investigate the five independent variables, such as reaction time, the molar ratio of H2O2/Fe2+, volume ratio of H2O2/WW, pH of waste, and ultrasonic density on COD removal. The experimental data was optimized. The optimization yields the conditions: Reaction time of 24 min, HP:Fe molar ratio of 2.8, HP:WW volume ratio of 1.9 ml/L, pH of 3.6 and an ultrasonic density of 1.8 W/L. The predicted value of COD was 91% and the experimental result was 90%. The composite desirability value (D) of the predicted percent of COD removal at the optimized level of variables was close to one (D = 0.991).

Wastewater nitrogen removal in SBRs, applying a step-feed strategy: from lab-scale to pilot-plant operation

2004 ◽  
Vol 50 (10) ◽  
pp. 89-96 ◽  
Author(s):  
S. Puig ◽  
M.T. Vives ◽  
Ll. Corominas ◽  
M.D. Balaguer ◽  
J. Colprim
Keyword(s):  
Organic Matter ◽  
Nitrogen Removal ◽  
Pilot Plant ◽  
Batch Reactor ◽  
Aerobic Oxidation ◽  
Scaling Up ◽  
Plant Operation ◽  
Feed Strategy ◽  
Real Wastewater ◽  
Biodegradable Organic Matter

One of the problems of nitrogen removal from wastewater when applying sequencing batch reactor (SBR) technology, is the specific use of organic matter for denitrification purposes. Since easily biodegradable organic matter is rapidly consumed under aerobic or anoxic conditions (i.e. aerobic oxidation or anoxic denitrification, respectively), it is an important factor to consider when scaling up SBRs from the laboratory to real plant operation. In this paper, we present the results obtained in relation to scaling up reactors from lab-scale to pilot-plant scale, treating real wastewater from two different locations: the laboratory and in situ, respectively. In order to make using easily biodegradable organic matter more efficient, the filling phases of SBR cycles were adjusted according to a step-feed strategy composed of 6 anoxic-aerobic events. Feeding only occurred during anoxic phases. The results obtained demonstrated that the methodology may be useful in treating real wastewater with high carbon and nitrogen variations, as it always kept effluent levels lower than the official standards require (effluent total COD lower than 125 mg COD/L and effluent Total Nitrogen lower than 15 mg N/L).

scholarly journals NiMo-sulfide supported on activated carbon to produce renewable diesel

2017 ◽  
Vol 22 (1) ◽  
pp. 71 ◽  
Author(s):  
Juan Tapia ◽  
Nancy Y Acelas ◽  
Diana López ◽  
Andrés Moreno
Keyword(s):  
Activated Carbon ◽  
Batch Reactor ◽  
Liquid Hydrocarbon ◽  
Product Distribution ◽  
Impregnation Method ◽  
Carbon Supports ◽  
Gaseous Products ◽  
Oxygenated Compounds ◽  
Metal Support Interaction ◽  
Metal Support

Due to their weak polarity and large surface area, activated carbon supports have the potential to enhance the dispersion of metal-sulfides. It is expected that the absence of a strong metal-support interaction can result in the formation of a very active and stable Ni-Mo-S phase. In this study, catalysts with different amounts of nickel and molybdenum supported on a commercial activated carbon were prepared by a co-impregnation method and characterized by BET, XRF, and SEM techniques. The catalytic activity for hydroprocessing of Jatropha oil was evaluated in a batch reactor, and the composition of the liquid and gaseous products were determined. Results showed that gaseous products are mainly composed of high amounts of propane and small amounts of other light hydrocarbons (C1 to C5). Liquid hydrocarbon products consisted of a mixture containing mainly n-paraffins of C15-C18 and some oxygenated compounds. The catalysts with a mass fraction<br />of 3 % Ni, 15 % Mo (Ni3Mo15/AC) presented the highest selectivity toward C17-C18 hydrocarbons, with a product distribution similar to a commercial<br />alumina-supported Ni-Mo-S catalyst.

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