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101.
Water–zeolite adsorption heat pump combined with single effect evaporation desalination process 总被引:1,自引:0,他引:1
The single effect evaporation desalination process combined with adsorption heat pump (ADVC) is modeled analyzed as a function of the system design and operating parameters. The analysis gives variations in the thermal performance ratio, the specific heat transfer area, and the specific flow rate of cooling water. The performance evaluation is made as a function of the brine boiling temperature, the difference in the temperature of the compressed vapor and the boiling brine, and the water content in the adsorption bed. Results show that the thermal performance ratio of this configuration is the highest among all single effect evaporation desalination systems. Moreover, the specific flow rate of the cooling water and the specific heat transfer area are similar to those of other single effect configurations. It should be stressed these promising features makes the ADVC system highly attractive to small and remote communities and of special interest in situations where energy cost is high. 相似文献
102.
Ultrasonication was evaluated as a pretreatment for biological hydrogen production from glucose in batch studies, in comparison with heat-shock pretreatment, acid pretreatment, and base pretreatment. The optimized sonication energy for hydrogen production using anaerobic digester sludge was 79 kJ/gTS. Sonication with temperature control (less than 30 °C) increased volumetric hydrogen production by 120% over the untreated sludge, and by 40% over the heat-shock and acid pretreated sludge, with a marginal (∼10%) increase in hydrogen production rate. Upon comparing the molar hydrogen yield in sonicated sludge with and without temperature control, the deleterious effect of heat on some hydrogen producers as reflected by a 30% decrease in yield to 1.03 mol H2/mol glucose is evident. Sonication with temperature control affected a 45% increase in molar hydrogen yield to 1.55 mol H2/mol glucose over heat-shock pretreatment at 70 °C for 30 min and acidification to pH 3.0 for 24 h at 4 °C. Sonication with temperature control produced a biomass yield of 0.13 g VSS/g COD, as compared to 0.24 g VSS/g COD for the untreated sludge. The hydrogen yield increased linearly with the molar acetate to butyrate ratio and decreased linearly with the biomass yield. 相似文献
103.
Emhemmed A. Youssef Elsayed Elbeshbishy Hisham Hafez George Nakhla Paul Charpentier 《International Journal of Hydrogen Energy》2010
The catalytic hydrogen production from hog manure using supercritical water gasification and partial oxidation was investigated in a batch reactor at a temperature of 500 °C, and pressure of 28 MPa using several metallic catalysts. Hog manure was characterized by a total and soluble chemical oxygen demand (TCOD, SCOD) of 57,000 and 28,000 mg/L, total and volatile suspended solids (TSS, VSS) of 25,000, 19,000, and ammonia of 2400 mg/L, respectively. The order of H2 production was the following: Pd/AC > Ru/Al2O3 > Ru/AC > AC > NaOH, and the order of COD reduction efficiency was as follows: NaOH > Ru/AC > AC > Ru/Al2O3 > Pd/AC. The behavior of the volatile fatty acids (VFAs), ethanol, methanol, ammonia, H2S, and sulfate was investigated experimentally and discussed. A 35% reduction in the H2 and CH4 yields was observed in the sequential gasification partial oxidation (oxidant at an 80% of theoretical requirement) experiments compared to the gasification experiments (catalyst only). Moreover, this reduction in gas yields was coincided with a 45% reduction in the liquid effluent chemical oxygen demand (COD), 60% reduction of the ammonia concentration in the liquid effluent, and 20% reduction in the H2S concentration in the effluent gas. 相似文献
104.
Batch anaerobic studies were conducted to study the effect of ultrasonication as a pre-treatment method for pulp waste prior to anaerobic hydrogen production. Pre-treatment was conducted by sonicating a 100 mL of pulp waste at different sonication times varying from 0.5 min to 30 min. The ultimate hydrogen production increased with increasing sonication time. The highest ultimate hydrogen production was achieved at a sonication time of 30 min and reflected an 88% increase over the unsonicated food waste, of 80 mL/g VSadded. The highest final VFAs concentration after fermentation (corresponding to 70% increase over the unsonicated food waste) was also achieved at a sonication time of 30 min. There were no significant differences between the acetate-to-butyrate ratios (HAc/HBu) for the all sonication times. The maximum hydrogen production rate at sonication time of 30 min was about 145% higher than that the unsonicated food waste. 相似文献
105.
Wan Nor Roslam Wan Isahak Mohamed W.M. Hisham Mohd Ambar Yarmo Taufiq-yap Yun Hin 《Renewable & Sustainable Energy Reviews》2012,16(8):5910-5923
The paper provides an updated review on thermal conversion of biomass for the production of liquid products referred as bio-oil. This technology is described focusing on the characterization of feedstock, reactor design, products formation and upgrading. For feedstock characterization is covered in terms of several pretreatment methods. The reactor designs are illustrated number of design ranging from fixed bed to circulating fluidized bed. The properties of bio-oil composition have caused increasingly extensive research to be undertaken to address properties that need modification and this area is reviewed in terms of physical, catalytic and chemical upgrading. The mechanism of the products formation is also illustrated by several chemical routes. Reactor parameters such as heating rate, temperature of pyrolysis, catalysts etc are reviewed. 相似文献
106.
Steady-state operational data from the integrated biohydrogen reactor clarifier system (IBRCS) during anaerobic treatment of glucose-based synthetic wastewater at HRT of 8 h and SRT ranging from 26 to 50 h and organic loading rates of 6.5–206 gCOD/L-d were used to calibrate and verify a process model of the system developed using BioWin. The model accurately predicted biomass concentrations in both the bioreactor and the clarifier supernatant with average percentage errors (APEs) of 4.6% and 10%, respectively. Hydrogen production rates and hydrogen yields predicted by the model were in close agreement with the observed experimental results as reflected by an APE of less than 4%, while the hydrogen content was well correlated with an APE of 10%. The successful modeling culminated in the accurate prediction of soluble metabolites, i.e. volatile fatty acids in the reactor with an APE of 14%. The calibrated model confirmed the advantages of decoupling of the solids retention time (SRT) from the hydraulic retention time (HRT) in biohydrogen production, with the average hydrogen yield decreasing from 3.0 mol H2/mol glucose to 0.8 mol H2/mol glucose upon elimination of the clarifier. Dynamic modeling showed that the system responds favorably to short-term hydraulic and organic surges, recovering back to the original condition. Furthermore, the dynamic simulation revealed that with a prolonged startup periods of 10 and 30 days, the IBRCS can be operated at an HRT of 4 h and OLR as high as 206 gCOD/L-d without inhibition and/or marked performance deterioration. 相似文献
107.
Nur Shuhaidatul Sarmiza Abdul Halim Kamal Shaik Fakiruddin Syed Atif Ali Badrul Hisham Yahaya 《International journal of molecular sciences》2014,15(9):15044-15060
Mesenchymal stem cells (MSCs) hold tremendous potential for therapeutic use in stem cell-based gene therapy. Ex vivo genetic modification of MSCs with beneficial genes of interest is a prerequisite for successful use of stem cell-based therapeutic applications. However, genetic manipulation of MSCs is challenging because they are resistant to commonly used methods to introduce exogenous DNA or RNA. Herein we compared the effectiveness of several techniques (classic calcium phosphate precipitation, cationic polymer, and standard electroporation) with that of microporation technology to introduce the plasmid encoding for angiopoietin-1 (ANGPT-1) and enhanced green fluorescent protein (eGFP) into human adipose-derived MSCs (hAD-MSCs). The microporation technique had a higher transfection efficiency, with up to 50% of the viable hAD-MSCs being transfected, compared to the other transfection techniques, for which less than 1% of cells were positive for eGFP expression following transfection. The capability of cells to proliferate and differentiate into three major lineages (chondrocytes, adipocytes, and osteocytes) was found to be independent of the technique used for transfection. These results show that the microporation technique is superior to the others in terms of its ability to transfect hAD-MSCs without affecting their proliferation and differentiation capabilities. Therefore, this study provides a foundation for the selection of techniques when using ex vivo gene manipulation for cell-based gene therapy with MSCs as the vehicle for gene delivery. 相似文献
108.
109.
Locally produced raw sulphur was used as an impregnant due to its availability at relatively low cost. For both laboratory
prepared samples and factory brick, sulphur impregnation at atmospheric pressure produces significant improvements in water
absorption, compressive strength and most physical properties. Simple equations were developed, from which the sulphur loading
required for any desired water absorption of the treated brick can be predicted accurately if the initial water absorption
value of the sample is known. 相似文献
110.
Sentuna Ayan Alsadoon Abeer Prasad P. W. C. Saadeh Maha Alsadoon Omar Hisham 《Neural Processing Letters》2021,53(1):177-209
Neural Processing Letters - Machine learning techniques, that are based on semantic analysis of behavioural attack patterns, have not been successfully implemented in cyber threat intelligence.... 相似文献