An Aerobic Piggery Slurry Treatment System with Integrated Heat Recovery and High-Rate Algal Ponds

1989 ◽  
Vol 21 (4-5) ◽  
pp. 277-287 ◽  
Author(s):  
I. F. Svoboda ◽  
H. J. Fallowfield
Keyword(s):  
Heat Recovery ◽  
Treatment System ◽  
High Rate ◽  
Effluent Treatment ◽  
Algal Productivity ◽  
Predicted Values ◽  
Quantity Of Heat ◽  
Fattening Pigs ◽  
Piggery Slurry ◽  
Good Agreement

A piggery with an integrated slurry removal and treatment system with heat recovery and two algal raceways for a secondary treatment of settled treated slurry has been built. Piggery slurry from about 250 fattening pigs and 100 weaners has been aerobically treated in a continuous culture reactor at 36°C. Metabolic heat and heat from the aerator after upgrading by a heat pump was utilized for space heating in a weaner house and in one of the algal raceways. Intermittent heating had little effect upon algal productivity and effluent treatment since the system was essentially light limited. Characteristics of treated slurry and quantity of heat evolved are in good agreement with predicted values by a mathematical model.

ANAEROBIC CO-CULTIVATION OF MULTI-ALGAL SPECIES WITH OIL PALM EMPTY FRUIT BUNCHES FOR MILL EFFLUENT TREATMENT AND BIOMETHANE PRODUCTION

2016 ◽  
Vol 78 (5-6) ◽  
Author(s):  
Ashfaq Ahmad ◽  
Syed Muhammad Usman Shah ◽  
Azizul Buang ◽  
Mohd Azmuddin Abdullah
Keyword(s):  
Oil Palm ◽  
Biogas Production ◽  
Algal Species ◽  
Anaerobic Treatment ◽  
Effluent Treatment ◽  
Empty Fruit Bunches ◽  
Chlorella Sp ◽  
Biomethane Production ◽  
Predicted Values ◽  
Good Agreement

This study investigated the optimization of anaerobic co-cultivation of multi-algal species with Oil Palm Empty Fruit Bunches (OPEFB) for Palm Oil Mill Effluent (POME) treatment and biomethane production. The highest removal of COD (95-98%), BOD (90-98%), TOC (81-86%) and TN (78-80%) were achieved after 7 days anaerobic treatment with the presence of microalgae. The highest biomethane (4,651.9 mL CH4/L POME/day) and the specific biogas production rate (0.124 m3/kg COD/day) with CO2 (2,265.9mL CO2/L POME/day) were achieved by co-cultivating N. oculata and Chlorella sp. (each at 1 mL/mL POME) with OPEFB (0.12 g/mL POME). The combination of N. oculata (2 mL/mL POME) with T. suecica or Chlorella sp. (each at 1 mL/mL POME), and OPEFB (0.12 g/mL POME) obtained high biomethane (4,018.9 mL CH4/L POME /day) but lower biogas (0.097 m3/kg COD/day) and CO2 (2,079.5mL CO2/L POME/day). Generally, low OPEFB and having all the three strains or increasing the level of any (2 mL/mL POME) especially T. suecica, could lower biomethane (870-953 mL CH4/L POME/day) and CO2 (803-854mL CO2/L POME/day), with the biogas around 0.08-0.09 m3/kg COD/day. The optimum conditions were predicted by Response Surface Methodology and the multiple coefficients of determination, r2, of 86% suggests good agreement between experimental and predicted values.

scholarly journals Seasonal Estimates and Uncertainties of Snow Accumulation from CloudSat Precipitation Retrievals

Atmosphere ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 363
Author(s):  
George Duffy ◽  
Fraser King ◽  
Ralf Bennartz ◽  
Christopher G. Fletcher
Keyword(s):  
Time Scales ◽  
Snow Water Equivalent ◽  
Spatial Scales ◽  
Snow Accumulation ◽  
High Latitudes ◽  
Percentage Points ◽  
Snow Water ◽  
Time Periods ◽  
Predicted Values ◽  
Good Agreement

CloudSat is often the only measurement of snowfall rate available at high latitudes, making it a valuable tool for understanding snow climatology. The capability of CloudSat to provide information on seasonal and subseasonal time scales, however, has yet to be explored. In this study, we use subsampled reanalysis estimates to predict the uncertainties of CloudSat snow water equivalent (SWE) accumulation measurements at various space and time resolutions. An idealized/simulated subsampling model predicts that CloudSat may provide seasonal SWE estimates with median percent errors below 50% at spatial scales as small as 2° × 2°. By converting these predictions to percent differences, we can evaluate CloudSat snowfall accumulations against a blend of gridded SWE measurements during frozen time periods. Our predictions are in good agreement with results. The 25th, 50th, and 75th percentiles of the percent differences between the two measurements all match predicted values within eight percentage points. We interpret these results to suggest that CloudSat snowfall estimates are in sufficient agreement with other, thoroughly vetted, gridded SWE products. This implies that CloudSat may provide useful estimates of snow accumulation over remote regions within seasonal time scales.

scholarly journals Waste heat recovery from Refrigeration machine

2019 ◽  
Vol 9 (2) ◽  
pp. 185-190
Keyword(s):  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Sea Water ◽  
Waste Heat ◽  
Experimental Tests ◽  
Air Conditioner ◽  
Heat Exchanges ◽  
Refrigeration Machine ◽  
New System ◽  
Good Agreement

With the aim of saving energy and to reduce global warming effect, our work focuses on the valorization of the waste heat evacuated by the condenser of a refrigeration machine (air-conditioner) for the desalination of sea water. In this paper, the conception of a new system combining airconditioning and desalination is realized. The modelling of the heat exchanges of each part of the system is realized. To improve the performance of the system, various experimental tests are represented and discussed. Comparison between simulation and experimental results shows a good agreement and present a courageous motive for the system application.

scholarly journals The control by ventilation of airborne bacterial transfer between hospital patients, and its assessment by means of a particle tracer: III. Studies with an airborne-particle tracer in an isolation ward for burned patients

1972 ◽  
Vol 70 (2) ◽  
pp. 299-312 ◽  
Author(s):  
A. Hambraeus ◽  
H. F. Sanderson
Keyword(s):  
Normal Activity ◽  
Cross Infection ◽  
High Rate ◽  
Airborne Particle ◽  
Isolation System ◽  
Hospital Patients ◽  
Particle Tracer ◽  
Isolation Ward ◽  
Burns Unit ◽  
Good Agreement

SUMMARYAirborne-particle transfer has been studied in a burns unit using potassium iodide particles. The observed rates of transfer were in good agreement with the values predicted by a theoretical model.An estimate of the average transfer between rooms under conditions of normal activity and with correctly functioning ventilation showed that the isolation system was highly efficient, the proportion transferred being probably less than 1 in 105. However, the ventilation often did not function as designed and under these conditions the efficiency was reduced by a maximum of a factor of ten. These rates of transfer do not seem great enough to account for the high rate of cross-infection found in this unit.

Prediction of Thermal Conductivities of Fibre Reinforced Composites using a Thermal-Electrical Analogy

2005 ◽  
Vol 13 (6) ◽  
pp. 637-644
Author(s):  
Young Jun Cho ◽  
Jae Ryoun Youn ◽  
Tae Jin Kang ◽  
Sung Min Kim
Keyword(s):  
Fibre Orientation ◽  
Reinforced Composites ◽  
Laminate Composites ◽  
Reinforced Composite ◽  
Electrical Analogy ◽  
Out Of Plane ◽  
Predicted Values ◽  
Fibre Reinforced Composites ◽  
Good Agreement ◽  
Thermal Conductivities

An approach for predicting the effective thermal conductivities of fibre reinforced composites has been developed, based on a thermal-electrical analogy. In the voxelization method, the unit cell of the laminate composites is divided into a number of volume elements, and the material properties considering the local variations of fibre orientation have been given to each element. By constructing a series-parallel thermal resistance network, the thermal conductivities of a fibre reinforced composite in both in-plane and out-of-plane directions have been predicted. The reported thermal conductivities of a graphite/epoxy composite of a balanced plain weave laminate were used for the comparison with the predicted values of the model, and good agreement was found.

Quantifying the thickness of each color material in multilayer transparent specimen based on transmission image

2020 ◽  
Vol 90 (21-22) ◽  
pp. 2522-2532
Author(s):  
Lijun Chen ◽  
Hua Shen ◽  
Fumei Wang
Keyword(s):  
Optical Depth ◽  
Low Cost ◽  
Estimating Equation ◽  
Color Film ◽  
Transparent Films ◽  
Transmission Image ◽  
Multilayer Specimen ◽  
Predicted Values ◽  
Physical Thickness ◽  
Good Agreement

Combing the color transmission image and the Beer–Lambert law shows a great application prospect in quantifying each material in multilayer specimen. Here, a novel, low-cost, and efficient optical algorithm is proposed to predict the thickness of each color material in a multilayer specimen from the color transmission image based on the Beer–Lambert Law. In this work, a normal scanner is employed to achieve the color transmission image of the monochrome transparent films. RGB values represent the transmitted intensity. A linear relationship between the optical depth and physical thickness is observed under different monochromatic lights. It is supposed that for a multilayer transparent film which consisted of different monochrome transparent films, the optical depth is related to the physical thickness of each monochrome transparent component. Therefore, an estimating equation is proposed to predict the thickness of each color material in the multilayer specimen. According to the result, the standard deviation of predicted thickness and practical thickness of each color film in the multilayer specimen is 0.93%. Fairly good agreement and high accuracy are obtained between the practical and predicted values, and the validity of this method is confirmed.

scholarly journals Foam Formation by Compression/Decompression Cycle of Soft Porous Media

2020 ◽  
Vol 4 (3) ◽  
pp. 31
Author(s):  
Phillip Johnson ◽  
Mauro Vaccaro ◽  
Victor Starov ◽  
Anna Trybala
Keyword(s):  
Mechanical Properties ◽  
Porous Media ◽  
Porous Material ◽  
Foam Formation ◽  
Compression Device ◽  
The Media ◽  
Minimum Separation ◽  
Soft Porous Media ◽  
Predicted Values ◽  
Good Agreement

A theory of the amount of foam produced by compression/decompression cycles of a soft porous media is developed. The amount of foam produced was found to be dependent on both the amount of surfactant within the media and the minimum separation between the plates of the compression device. The latter is determined by the mechanical properties of the soft media. The theory also shows the importance of the decompression of the media as this is the mechanism of where the air penetrates into the soft porous material. The accumulated air is used during the compression stage for foam formation. The theoretically predicted values of foam mass are found to have good agreement with experimental observations, which validates the theory predictions. The theory also predicts independence of the foam produced in terms of the frequency of compression/decompression cycles, which agrees with our experimental observations.

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