scholarly journals Preliminary Studies on the Use of Sawdust and Peanut Shell Powder as Adsorbents for Phosphorus Removal from Water

2019 ◽  
Vol 3 (1) ◽  
pp. 33 ◽  
Author(s):  
Marian Asantewah Nkansah ◽  
Moses Donkoh ◽  
Osei Akoto ◽  
James Hawkins Ephraim

Phosphorus is one of the key nutrients that contribute to eutrophication and excess algal growth in rivers and lakes and other surface water bodies. Such algal blooms affect the life of aquatic organisms, especially fishes, and block sunlight from reaching bottom dwelling plants thus inhibiting photosynthesis and stunting growth. In this study, sawdust and peanut shell powder were explored as adsorbents for the removal of phosphorus from aqueous solutions. A series of batch experiments were conducted to determine the effects of adsorbent dosage, initial phosphorus concentration and contact time on the rate of phosphorus removal. The results showed that 78% and 39% of phosphorus was removed by sawdust and peanut shell powder respectively at adsorbate concentrations of 10 mg/l (total P) for a period of 180 min at an adsorbent dosage of 0.4 g. It was also found that the highest phosphorus removal occurred at adsorbent mass of 0.4 g of sawdust and 0.6 for peanut shell powder. Adsorption data were fitted to the linearised forms of the Freundlich and Langmuir isotherm models to determine the water - adsorbent partitioning coefficient. Sawdust proved to be a better adsorbent than peanut shell powder.

2019 ◽  
Vol 116 (1) ◽  
pp. 116
Author(s):  
Xuejiao Zhou ◽  
Yongli Chen ◽  
Wentang Xia ◽  
Jianguo Yin ◽  
Xiaoli Yuan

The present study aims to develop a new potentially low-cost and efficient approach to removing soluble inorganic phosphorus from acid leaching wastewater. This wastewater was of high acidity and high phosphorus content. Low-grade oolitic hematite with high phosphorus (LGOHWHP) was chosen as an economic adsorbent and was also used to adjust the acidity of the solution. The adsorption isotherms, adsorption thermodynamics, and effect of various parameters such as pH value, contact time, temperature and adsorbent dosage on the phosphorus removal from wastewater were investigated. The results showed that pH value and adsorbent dosage have a significant impact on the phosphorus removal. The phosphorus adsorption results fitted very well to Langmuir and Freundlich adsorption isotherm models, and the adsorption process was an endothermic process. At the optimum parameters pH 5.5, reaction temperature of 302 K with 20 g L−1 LGOHWHP, the phosphorus removal percentage of about 95% and the phosphorus concentration in the wastewater of about 0.27 mg L−1 are achieved after 60 min. The results indicate that the phosphorus concentration in wastewater after dephosphorization by the LGOHWHP completely meets the requirements of the national wastewater discharge standard in China. This research provides an efficient and environmentally friendly technology to remove phosphorus from wastewater.


2019 ◽  
Vol 80 (5) ◽  
pp. 846-854
Author(s):  
Vitor Tonzar Chaves ◽  
Dione Mari Morita ◽  
Iara Regina Soares Chao ◽  
Ronan Cleber Contrera

Abstract This study proposes a technology conceived based on an integrative approach that aims to promote phosphorus recovery and to recycle ferric water treatment sludge (FWTS), using it as a phosphorus adsorbent which may be applied as a soil ameliorant after reaching saturation. The assessed pilot plant operated with a daily influent flow of 360 litres and presented a removal efficiency of 94.4% ± 3.2% for chemical oxygen demand (COD) and of 91.2% ± 7.8% for suspended solids. It also presented promising results for phosphorus removal. The maximum efficiency of dissolved reactive phosphorus removal was 95% on the first day and it decreased until reaching adsorbent saturation. The estimated breakthrough time was one year in the condition in which the filling medium of a second constructed wetland was only FWTS. In this situation, the effluent phosphorus concentration was 0.2 mg·L−1. The authors concluded that the application of FWTS in a constructed wetland bed is an interesting alternative. Batch adsorption experiments were run using phosphorus stock solution. Langmuir and Freundlich adsorption isotherm models were obtained for different initial pH values. The maximum adsorption capacity decreased as the initial pH was increased; values ranged from 4.76 mg P·g−1 (pH = 3.9) to 1.44 mg P·g−1 (pH = 9.0).


2013 ◽  
Vol 781-784 ◽  
pp. 2138-2141
Author(s):  
Hong Jie Sun ◽  
Shao Hua Yang ◽  
Yu Bo Cui

Phosphorus removal from wastewater has always been given serious attention in sewage treatment. Eutrophication can happen if phosphorus wastewater is directly discharged into natural water and high phosphorus-contained irrigation water may lead crops beat down. The research investigated the phosphorus removal efficiency in wastewater by shell powder. The experiment results showed that the best removal effect could meet the Wastewater Treatment Plant Discharge Standard (GB18918-2002) Grade I-A in China, which can be achieved under the conditions of the dosage of shell powder solution 1 ml, pH > 11 and precipitation one to four hours at the initial phosphorus concentration of about 3 mg/L.


2020 ◽  
Vol 12 (15) ◽  
pp. 5982
Author(s):  
Hong Ha Thi Vu ◽  
Mohd Danish Khan ◽  
Van Tan Tran ◽  
Dang Viet Quang ◽  
Van-Duong Dao ◽  
...  

To use calcite mud waste generated from the paper production process, calcite mud was treated by calcination and then applied as a sorbent agent to remove phosphorus from an aqueous solution. The pre-treatment muds were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. The effects of calcite mud with different calcination temperatures on phosphorus removal were investigated. Different sorbent dosages, contact times, and initial phosphorus concentration conditions were also studied to understand the phosphorus removal mechanism. The results show that phosphorus removal efficiency was increased by increasing the calcination temperature of the mud. The phosphorus removal efficiency over 10 min increased by 35%, 82%, 98%, and 100% with 4.5, 6.75, 9.0, and 11.25 mg, respectively, of calcite mud calcined at 1000 °C. However, the efficiency decreased as initial phosphorus concentration increased. To study the phosphorus removal trend, the pseudo-first-order, pseudo-second-order, and intraparticle diffusion kinetic models were used. The Langmuir and Freundlich isotherm models were also used to further investigate the phosphorus adsorption mechanism characteristics of the calcite mud.


1969 ◽  
Vol 26 (12) ◽  
pp. 3101-3132 ◽  
Author(s):  
M. W. Smith

When artificial fertilizers were added to unstratified, soft-water Crecy Lake (20 ha), New Brunswick, in three years (1946, 1951, and 1959), the lake was sufficiently self-regulatory that the artificial enrichments had only a temporary effect on organic production. The induced eutrophication proved largely reversible, with minor evidence of hastened senescence of the lake over an 18-year period. Each fertilization provided 210 ppb (parts per billion) of nitrogen (N), 390 ppb of phosphorus (P), and 270 ppb of potassium (K) to the water if the fertilizers were equally distributed throughout the lake.The highest concentrations of total P, determined daily after the fertilizations in 1951 and 1959, were 220 ppb after 2 days and 192 ppb after 1 day, respectively. The concentration of inorganic P declined rapidly from about 150 ppb the day after the fertilizations in 1951 and 1959 to < 10 ppb at a percentage loss per day of 5.5. Concentrations of organic P were highest 5 (80 ppb, 1951) and 8 (43 ppb, 1959) days after the fertilizations and declined to equilibration above prefertilization values for 3–4 months, and then to prefertilization values during the next years. Phosphorus lost in the drainage from the lake, assessed only in 1951 and 1959, was equivalent in these years to 8.5 and 12% of the amounts added in the fertilizers.Limited observations indicated an increase of nitrate N in the water immediately after fertilization, but then a rapid loss. Deficits in dissolved oxygen were greatest under ice in the winters immediately after algal blooms induced by the fertilizers, but were serious in only about 30% of the volume of the lake. Specific conductance of the water exhibited minor change with fertilization.Pronounced algal blooms, not previously recorded for the lake, followed each fertilization. Years of fertilization, and the next, were marked by blooms of Anabaena. Intensified growth of Spirogyra usually followed closely the blooms of Anabaena. In the 3rd year after fertilization algal growth was weak, at prefertilization densities. During blooms of Anabaena the numbers of zooplankters and bottom organisms, and growth of submerged, rooted aquatic vegetation, decreased. Zooplankton and bottom fauna were most abundant 2–4 years after fertilizations. Of the rotifers, three out of eight species became abundant. Of the planktonic microcrustaceans, Leptodiaptomus was always the most numerous; Diaphanosoma and Daphnia were more numerous after the last fertilization (1959) than they were earlier. Among the bottom organisms, Hyalella, chironomids, Amnicola, and sphaeriids increased most in abundance after the fertilizations.


2010 ◽  
Vol 7 (5) ◽  
pp. 443 ◽  
Author(s):  
Michael R. Grace ◽  
Todd R. Scicluna ◽  
Chamindra L. Vithana ◽  
Peter Symes ◽  
Katrina P. Lansdown

Environmental context.Effective mitigation of algal blooms, and their associated detrimental impacts on flora and fauna, requires an understanding of the factors leading to bloom development, including nutrients, light and hydrodynamics. We investigated a shallow, freshwater lake and demonstrate that there is sufficient bioavailable phosphorus to annually generate a large algal biomass. Extensive, seasonal phosphorus release from sediments is controlled by the interactions of the biogeochemical cycles of nitrogen, carbon, oxygen, iron and sulfur. Abstract.The shallow, polymictic Ornamental Lake in the Royal Botanic Gardens, Melbourne, Australia, has suffered significant blooms of toxic Anabaena then Microcystis species every summer over the last decade. Although the hydrodynamic conditions of the water column are conducive for algal growth, the prolific growth is controlled by the bioavailable phosphorus concentration. Springtime phosphorus fluxes of 0.1–0.2 mmol m–2 day–1 from the sediment contribute to bloom development. These rates are also observed in anoxic sediment core incubations. Diel stratification, combined with high oxygen consumption associated with organic carbon loading, favour P release. Release rates may be amplified by the effects of sulfate reduction on P sorption onto FeIII (oxyhydroxide) surfaces. Sulfate concentrations are at the threshold where methanogenesis is inhibited in anoxic conditions. Effective bloom mitigation will require a >100-fold reduction in P concentrations, which may be achieved through macrophyte planting and inducing greater water flow through the lake system.


1992 ◽  
Vol 27 (2) ◽  
pp. 271-286 ◽  
Author(s):  
Sonia Paulino Mattos ◽  
Irene Guimarães Altafin ◽  
Hélio José de Freitas ◽  
Cristine Gobbato Brandão Cavalcanti ◽  
Vera Regina Estuqui Alves

Abstract Built in 1959, Lake Paranoá, in Brasilia, Brazil, has been undergoing an accelerated process of nutrient enrichment, due to inputs of inadequately treated raw sewage, generated by a population of 600,000 inhabitants. Consequently, it shows high nutrient content (40 µg/L of total phosphorus and 1800 µg/L of total nitrogen), low transparency (0.65 m) and high levels of chlorophyll a (65 µg/L), represented mainly by Cylindrospermopsis raciborskii and sporadic bloom of Microcystis aeruginosa, which is being combatted with copper sulphate. With the absence of seasonality and a vertical distribution which is not very evident, the horizontal pattern assumes great importance in this reservoir, in which five compartments stand out. Based on this segmentation and on the identification of the total phosphorus parameter as the limiting factor for algal growth, mathematical models were developed which demonstrate the need for advanced treatment of all the sewage produced in its drainage basin. With this, it is expected that a process of restoration will be initiated, with a decline in total phosphorus concentration to readings below 25 µg/L. Additional measures are proposed to accelerate this process.


1985 ◽  
Vol 17 (11-12) ◽  
pp. 297-298 ◽  
Author(s):  
Takao Murakami ◽  
Atsushi Miyairi ◽  
Kazuhiro Tanaka

In Japan various biological phosphorus removal processes have recently been researched by laboratory or pilot plant scale studies and most of them have shown good results. Based on these results, the Japan Sewage Works Agency has conducted a full scale study of the biological phosphorus removal process from June 1982 until February 1983, which was the first full scale operation of this process in Japan. The main purpose of the study was to evaluate phosphorus removal efficiency and also nitrogen removal efficiency of the process and in addition, to ascertain the important operating factors of the process. For the study a treatment train of a large scale sewage treatment plant was remodelled. The aeration tank of 3.825 m3 volume was divided into four equal cells. The whole train including return sludge line was operated entirely independently of the other trains. During the experiment the train was operated under two different modes, Mode 1 and Mode 2. In Mode 1, the train was operated as an A/O process, the first cell of the aeration tank being anaerobic and the other cells oxic. In Mode 2, the train was operated as a Modified Phoredox process. In this case, the first cell was anaerobic, but the second cell was anoxic and nitrified liquor was returned to it from the end of the oxic cells. Mode 1 and Mode 2 were further divided into many ‘runs' and the flow rate varied between 12,550 m3 d−1 and 25,270 m3 d−1 , corresponding to retention times of 7.3 hours and 3.6 hours, respectively. Throughout the experimental period the mean value of influent (primary effluent) total-P concentration was 3.38 mg 1−1 , and that of the final effluent was 0.47 mg 1−1 . A cumulated frequency curve of the data showed that about 93% of measured effluent total-P was below 1.0 mg l−1 . Therefore, it can be concluded that with these influent total-P levels, biological phosphorus removal processes can sufficiently satisfy the effluent standard of 1 mg 1−1 total-P. Even when the process was operated as a Modified Phoredox Process, no obstruction to phosphorus removal because of nitrification was observed and phosphorus removal remained good. However, since the sewage treatment plant treated influent from a combined sewerage system, phosphorus removal was sometimes affected by heavy rainfalls. In such cases phosphorus release in the anaerobic cell was insufficient because of increased influent NOx concentration and accordingly increased denitrification level in the anaerobic cell. Therefore, as a result, enhanced phosphorus uptake in the following cells could not be observed. Higher process stability can be expected if an effective countermeasure to high influent NOx concentration can be made. Influence of flow rate fluctuation on the process was also studied. The treatment train was operated for a week under a daily flow rate fluctuation pattern which ranged between 460 m3 hr−1 and 820 m3 hr−1 . Nevertheless, the effluent total-P concentration showed no increase and stayed constantly lower than 0.5 mg 1−1. The oxidation reduction potential (ORP) was an effective control index to evaluate the degree of phosphorus release in the anaerobic cell. Water temperature did not affect phosphorus release and uptake rates.


1999 ◽  
Vol 39 (12) ◽  
pp. 63-67 ◽  
Author(s):  
B. L. Turner ◽  
P. M. Haygarth

Phosphorus (P) transfer from agricultural land to surface waters can contribute to eutrophication, excess algal growth and associated water quality problems. Grasslands have a high potential for P transfer, as they receive P inputs as mineral fertiliser and concentrates cycled through livestock manures. The transfer of P can occur through surface and subsurface pathways, although the capacity of most soils to fix inorganic P has meant that subsurface P transfer by leaching mechanisms has often been perceived as negligible. We investigated this using large-scale monolith lysimeters (135 cm deep, 80 cm diameter) to monitor leachate P under four grassland soil types. Leachate was collected during the 1997–98 drainage year and analysed for a range of P fractions. Mean concentrations of total P routinely exceeded 100 μg l−1 from all soil types and, therefore, exceeded P concentrations above which eutrophication and algal growth can occur. The majority of the leachate P was in algal-available Mo-reactive (inorganic) forms, although a large proportion occurred in unreactive (organic) forms. We suggest that subsurface transfer by leaching can represent a significant mechanism for agricultural P transfer from some soils and must be given greater consideration as a potential source of diffuse P pollution to surface waters.


1999 ◽  
Vol 40 (1) ◽  
pp. 357-364 ◽  
Author(s):  
A. Kungolos ◽  
P. Samaras ◽  
A. M. Kipopoulou ◽  
A. Zoumboulis ◽  
G. P. Sakellaropoulos

The effects of three common agrochemicals, lindane, methyl parathion and atrazine, on crustacean Daphnia magna, alga Selenastrum capricornutum and marine bacterium Vibrio fischeri were investigated in this study. Methyl parathion was the most toxic compound towards all three organisms, while lindane was more toxic to Daphnia magna and Vibrio fischeri than atrazine, and atrazine was more toxic to Selenastrum capricornutum than lindane. Among the three aquatic organisms, Selenastrum capricornutum was most sensitive in detecting lindane and atrazine toxicity, while Daphnia magna was most sensitive in detecting methyl parathion toxicity. The interactive effects of the pesticides were also investigated. The interactive effect between lindane and methyl parathion on survival of Daphnia magna was synergistic, while the ones between lindane and atrazine and between methyl parathion and atrazine were generally additive. The interactive effect of the three pesticides applied together on Daphnia magna was synergistic. The interactive effect of the three pesticides on the growth of Selenastrum capricornutum was antagonistic with few cases of addition, while the effect of all the three pairs of pesticides on algal growth was also antagonistic. The interactive effect of lindane and methyl parathion on Vibrio fischeri was additive.


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