oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Effect of Sewage Sludge on Germination, Growth and Biomass Yield of Sorghum in Calcareous Soils  [PDF]
Ali A. Al-Jaloud
Pakistan Journal of Biological Sciences , 1999,
Abstract: Effect of sewage sludge on germination, growth and biomass yield of sorghum crop was studied utilizing three calcareous soils and the sewage sludge at the rate of 0, 25, 50 and 75 Mg ha -1 in a pot experiment. The mean crop germination ranged between 77.5-97.5 per cent and there was no significant reduction in germination due to sewage sludge application. Mean plant height ranged between 33.98-77.60 cm and the mean biomass ranged between 0.075-0.525 kg per pot in different sewage sludge treatments. The plant height and the biomass yield increased significantly with an increase in sewage sludge application. There was an increasing trend in plant height and total biomass yield in heavy textured soil than other soils. There was no significant effect of varying CaCO3 contents of soils on crop germination, plant height and biomass yield receiving different rates of sewage sludge. In conclusion, there exists an excellent potential for the use of sewage sludge not only as organic matter but also a promising source of plant nutrition for increasing the productivity of sandy calcareous soils in an arid environment. The research findings also highlighted the usefulness of sewage sludge and sewage waste for its utilization as organic matter for reasonable forage production as well as to minimize the expected environmental hazards from land disposal of these sewage wastes.
Enzyme activity and microbial biomass in an Oxisol amended with sewage sludge contaminated with nickel
Revoredo, Marcos Donizeti;Melo, Wanderley José de;
Scientia Agricola , 2007, DOI: 10.1590/S0103-90162007000100009
Abstract: the role of nickel in soils of tropical areas under the application of sewage sludge is still not very well known. this study was carried out under greenhouse conditions in jaboticabal, s?o paulo state, brazil, with the objective of evaluating the impact of the application of sewage sludge previously contaminated with rates of nickel (329, 502, 746 and 1119 mg kg-1, dry basis) on a soil cropped with sorghum, in relation to soil enzyme activity and soil microbial biomass. soil samples were collected at the beginning and the end of the experiment. the experimental design was completely randomized, with five treatments (control and four rates of ni in the sewage sludge) and four replications. c and n of the soil microbial biomass and enzyme activities (acid and alkaline phosphatases) were sensitive indicators for impact evaluation caused by sewage sludge contaminated with nickel. there were positive correlations between "total" and extractable nickel (mehlich 1) with c-microbial biomass and negative with the microbial c/n relationship. n-microbial biomass correlated positively with "total" and extractable ni at the last sampling. at the end of the experiment, the acid phosphatase activity correlated negatively with "total" ni while the alkaline phosphatase correlated with both forms of the metal.
The Effect of Physical Factors on Fecal Coliform Viability Rate in Sewage Sludge  [PDF]
S. N. Al-Bahry, I. Y. Mahmoud, S. K. Al-Musharafi
Journal of Geoscience and Environment Protection (GEP) , 2014, DOI: 10.4236/gep.2014.22002
Abstract: Experiments were conducted on the survival rate of fecal coliform after spreading the sewage sludge for desiccation on sludge beds in an open field throughout the year. The ambient temperature, humidity, sunlight intensity and solar radiation were measured during the period of sludge desiccation. The maximum average temperature, sunlight intensity and solar radiation were recorded throughout the year. During May and August the minimum microbial counts were recorded after four weeks of sludge desiccation. Relative humidity did not have significant effect on survival rate. The minimum microbial counts were taken after four weeks of sludge drying. When the sludge was mixed with three different media, the maximum count of fecal coliform was presented when soil mixed with sludge and irrigated with treated sewage effluent (TSE). When soil mixed with sludge irrigated with well water, the number of fecal coliform count dropped significantly. The minimum count occurred when compost was used instead of sludge. This was a clear indication that the source of contamination was from sludge and was mostly contributed by the TSE irrigation. The use of dried sludge after four weeks of treatment had the lowest fecal coliform count
and was safe to be used as fertilizer for farming. Oman is located in a semi-equatorial belt with arid environmental conditions which are ideal for elimination of microbial pathogens. Thus, sludge desiccation in such environmental conditions, specifically during the hot months of the year, is perfect for such practice.
Combustion Characteristics of Sewage Sludge and Algae  [PDF]
Yaman Kumar Sahu, Pravin Kumar Sahu, Suryakant Chakradhari, Khageshwar Singh Patel
Natural Resources (NR) , 2016, DOI: 10.4236/nr.2016.74019
Abstract: Sewage sludge is a good source of energetically desirable compounds and green algae in developing country like India. In this work, the combustion characteristics of sewage sludge and green algae are described. The calorific value (CV) of dried sewage sludge (n = 7) and green algae (n = 11) was ranged from 1800 to 6250 and 3700 to 6280 kcal/kg with mean value of 3999 ± 1347 and 4428 ± 547 kcal/kg, respectively. The effect of proximate variables and water quality parameters in the CV of sludge and algae are discussed.
Characteristics of sewage sludge and distribution of heavy metal in plants with amendment of sewage sludge
DAI Jia-yin,CHEN Ling,ZHAO Jian-fu,MA Na,
DAI Jia-yin
,CHEN Ling,ZHAO Jian-fu,MA Na

环境科学学报(英文版) , 2006,
Abstract: In order to better understand land application of sewage sludge, the characterization of heavy metals and organic pollutants were investigated in three different sewage sludges in Shanghai City, China. It was found that the total concentrations of Cd in all of sewage sludge and total concentrations of Zn in Jinshan sewage sludge, as well as those of Zn, Cu, and Ni in Taopu sludge are higher than Chinese regulation limit of pollutants for sludge to be used in agriculture. Leachability of Hg in all of studied samples and that of Cd in Taopu sewage sludge exceed the limit values of waste solid extraction standard in China legislation. Based on the characteristics for three kinds of sewage sludge, a pot experiment was conducted to investigate the effect of soil amended with Quyang sewage sludge on the accumulation of heavy metal by Begonia semperflorens-hybr; Ophiopogon japonicus (L.F.) Ker-Gaw; Loropetalum chindense-var. rubrum; Dendranthema morifolium; Viola tricolor; Antirrhinum majus; Buxus radicans Sieb; Viburnum macrocephalum; Osmanthus fragrans Lour; Cinnamomum camphora siebold and Ligustrum lucidum ait. Results showed that 8 species of plant survived in the amended soil, and moreover they flourished as well as those cultivated in the control soil. The heavy metal concentration in plants varied with species, As, Pb, Cd and Cr concentration being the highest in the four herbaceous species studied, particularly in the roots of D. morifolium. These plants, however, did not show accumulator of As, Pb, Cd and Cr. The highest concentration of Ni and Hg was found in the roots of D. morifolium, followed by the leaves of B. semperflorens-hybr. Levels of Zn and Cu were much higher in D. morifolium than in the other plant species. D. morifolium accumulated Ni, Hg, Cu and Zn, which may contribute to the decrease of heavy metal contents in the amended soil. Treatment with sewage sludge did not significantly affect the uptake of heavy metals by the L. chindense-var. rubrum, however, it significantly affected the uptake of heavy metals by D. morifolium.
Comparing the Performance of Sorghum Silage with Maize Silage in Feedlot Calves  [PDF]
H. Fazaeli,H.A. Golmohhammadi,A. Al-Moddarres,S. Mosharraf
Pakistan Journal of Biological Sciences , 2006,
Abstract: Sweet sorghum and maize were cultivated, in research station where the agronomic parameters recorded and the forage harvested and ensiled when the seeds were at dough stage. At the second step, 32 yearling male calves with 229±1.2 kg initial weight, were used to assess their fattening performances with two types of silages (sorghum and maize), using a completely randomized design with four diets where maize silage was substituted with sorghum silage in the amount of 0, 33, 66 and 100% of diets I, II, III and VI, respectively. The sorghum seed required ha-1 was much lower (4 vs. 30 kg ha-1) than that of the maize as well as the number of irrigations (8 vs. 11). However, the amount of forage yield per hectare was relatively similar for both crops. During the 120 days of feeding trial, average daily gain were 1037, 1068, 1010 and 1157 g for the diets I, II, III and VI, respectively which were not significantly different (p<0.05). The average dry mater intake was 7.50, 7.56, 7.74 and 8.06 kg, feed conversion ratio 7.23, 7.07, 7.66 and 6.59, respectively that were not significantly different (p<0.05). It conclusion, feeding performance of the sorghum silage was similar to the maize silage with the advantages of agronomy parameters.
Nutritive value of diferents silage sorghum (Sorghum bicolor L. Moench) cultivares
Borba, Luis Felipe Pereira;Ferreira, Marcelo de Andrade;Guim, Adriana;Tabosa, José Nildo;Gomes, Luiz Henrique dos Santos;Santos, Viviany Lúcia Fernandes dos;
Acta Scientiarum. Animal Sciences , 2012, DOI: 10.4025/actascianimsci.v34i2.12853
Abstract: nutrition values of silages from different sorghum cultivars are evaluated. five 26-kg castrated crossbred lambs, housed in pens equipped with feces and urine collectors for the study of their metabolism, were employed in a 5 x 5 latin square experimental design. treatments consisted of silage from five different sorghum cultivars: ipa 1011 and ipa 2564 (grain sorghum), ipa 2502 (dual purpose sorghum), ipa fs-25 and ipa 467 (forage sorghum). protein level was corrected to 12% by adding a mixture of urea: ammonium sulfate (9:1). treatments ipa 1011, ipa 2564 and ipa 2502 provided high intake of dry matter, total carbohydrate and total digestible nutrients, and low intake of neutral detergent fiber. cultivars ipa 1011 and ipa 2564 provided high apparent crude protein digestibility coefficient, whereas cultivars ipa 1011 and ipa 2564 had high total digestible nutrient levels. all cultivars provided positive nitrogen. owing to nutrient intake and digestibility values, grain sorghum silages evidenced high potential in ruminant nutrition.
Effect of Sewage Sludge on Soil Physical Properties  [cached]
M. R. Bahremand,M. Afyuni,M. A. Hajabbassi,Y. Rezaeinejad
Journal of Science and Technology of Agriculture and Natural Resources , 2003,
Abstract: A field experiment was conducted to investigate the effects of sewage sludge and of time lapse after sludge application on soil physical properties. Four sewage sludge treatments (0, 25, 50, and 100 ton/ha) in a complete randomized block design with three replications were applied and mixed to a depth of 20 cm. Wheat was planted and soil physical properties were measured 23, 85, 148, and 221 days after sewage sludge application. Sewage sludge application significantly increased MWD, hydraulic conductivity, final infiltration rate, moisture percentage at 1/3 and 15 bars, and plant available soil moisture, while it significantly decreased soil bulk density. In general, the best results obtained with the 100 ton/ha sewage sludge treatment. Time lapse after sewage sludge application caused soil physical properties to approach the values of the control. However, even 221 days after sludge application, the 50 and 100 ton/ha treatments had significantly different values compared with the control treatment. The results in this research show that sewage sludge can help to improve soil physical conditions and this effect persists over long periods. This effect is specially important with plant available soil moisture and infiltration.
Evaluation of the Pozzolanic Activity of Sewage Sludge Ash  [PDF]
M. A. Tantawy,A. M. El-Roudi,Elham M. Abdalla,M. A. Abdelzaher
ISRN Chemical Engineering , 2012, DOI: 10.5402/2012/487037
Abstract: Raw sewage sludge was characterized by XRD, FTIR, SEM, and TGA techniques and incinerated in temperature range 650–950°C for 2?h. The effect of incineration temperature on the microstructure and pozzolanic activity of the resultant ash was investigated by techniques mentioned above as well as Chapelle test. It was concluded that incineration of sewage sludge affects the microstructure and pozzolanic activity of the resultant ash. During incineration at temperatures lower than 800°C, amorphous silica captures fixed carbon resulting from incomplete combustion conditions whereas at higher temperatures crystallization of amorphous silica was enhanced. Hydration products formed from hydrothermal treatment of silica fume with lime is amorphous whereas that of sewage sludge ash is fibrous. Hence, incineration of sewage sludge ash must be optimized at 800°C to preserve the pozzolanic activity of the resultant ash. 1. Introduction Sewage is the collection of wastewater effluents from domestic, hospital, commercial, industrial establishments, and rain water. The objective of sewage treatment is to produce treated sewage water and sewage sludge suitable for safe discharge into the environment or reuse [1]. The most common treatment options for sewage sludge include anaerobic digestion, aerobic digestion, and composting. Choice of the treatment method depends on the amount of sludge and other site-specific conditions [2]. Sewage sludge tends to accumulate heavy metals existing in the wastewater. The composition of sewage sludge and its content of heavy metals vary widely depending on the sludge origins and treatment options [3]. In past decades, sewage sludge was primarily disposed to landfills and seawaters [4]. Space limitations on existing landfills and increasing environmental concerns such as groundwater pollution from landfill leachate, odor emission and soil contamination have prompted the investigation of alternative disposal routes [5]. Sewage sludge has been used in agriculture as fertilizer and soil amendment [6]. However heavy metals such as Zn, Cu, Ni, Cd, Pb, Hg, and Cr are principal elements restricting the use of sludge for agricultural purposes [3]. The solidification/stabilization of sewage sludge in cementitious matrix has been evaluated [7]. Sewage sludge adversely affects durability of concrete, mainly due to the organic material which retards setting and heavy metals which interfere with the hardening reactions [8]. Hence, sewage sludge addition in concrete was limited to 10?wt.% and the solidified concrete was recommended for use in certain
The drying of sewage sludge by immersion frying
Silva, D. P.;Rudolph, V.;Taranto, O. P.;
Brazilian Journal of Chemical Engineering , 2005, DOI: 10.1590/S0104-66322005000200015
Abstract: the objective of this work was to dry sewage sludge using a fry-drying process. the frying experiments were carried out in commercial fryers modified by adding thermocouples to the setup. during frying, typical drying curves were obtained and it was verified that, in relation to the parameters: oil temperature, oil type and shape of the sample, the shape factor the most effect on the drying rate, at least within the range chosen for the variables studied. oil uptake and calorific value were also analyzed. the calorific value of the samples increased with frying time, reaching values around 24mj/kg after 600s of frying (comparable to biocombustibles such as wood and sugarcane bagasse). the process of immersion frying showed great potential for drying materials, especially sewage sludge, obtaining a product with a high energy content, thereby increasing its value as a combustible.
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.