Phosphorus Concentration In Wastewater Research Articles

An efficient technology of phosphorous removal from wastewater by the low-grade oolitic hematite with high phosphorous

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.

Fly ash particles as a filter material in on‐site wastewater treatment systems for total phosphorus reduction

AbstractIn this paper, a simple filter model is used to determine the utility of fly ash fraction for total phosphorus reduction. Fly ash, which is introduced in this work, is a fraction of natural fly ash of particle size greater than 0.3 mm, and is used as a media filter material to reduce the total phosphorus concentration in wastewater. The results of a single snapshot sample indicate that fly ash fraction can hold wastewater due to its high specific surface area and release the final treated effluent at an appropriate level in terms of total phosphorus concentration. The physical and hydraulic characteristics and also the chemical composition of this fly ash fraction, and then the results of a single snapshot sample encourage both towards considering the material for total phosphorus reduction. Furthermore, this study proposes the valorization of fly ash waste material and its application as media filter for total phosphorus reduction.

Study of The Maximum Uptake Capacity on Various Sizes of Electric Arc Furnace Slag in Phosphorus Aqueous Solutions

The high content of uncontrolled phosphorus concentration in wastewater has emerged as a major problem recently. The excessive amount of phosphorus that is originated from domestic waste, unproper treated waste from septic tanks, as well as agricultural activities have led to the eutrophication problem. Therefore, a laboratory experiment was initiated to evaluate the potential of the Electric Arc Furnace Slag (EAFS), a by-product waste from steel making industry in removing phosphorus concentrations in aqueous solutions. In this work several particle sizes ranging from (9.5-12.4 mm, 12.5-15.9 mm, 16.0-19.9 mm, 20.0-24.9 mm, 25-37.4 mm) with a known weight (20±0.28 g, 40±0.27 g, 60±0.30 g, 80±0.29 g and 100±0.38 g) were used to study the effect of different particle sizes towards phosphorus removal. Each particle size of EAFS was shaken in synthetic phosphorus solutions (10 mg/l, 20 mg/l, 30 mg/l, 40 mg/l and 50 mg/l) at a contact time of 2 hours. Final concentrations of phosphorus were sampled and the measurement was made using WESTCO Discrete Analyzer equipment. Results showed that the highest of the maximum uptake capacity of each EAFS particle size distribution achieved at 0.287, 0.313, 0.266, 0.241 and 0.25 mg/g as particle size range was varied from 9.5-12.4 mm to 25-37.4 mm. In conclusion, the maximum uptake capacity of each EAFS mostly was determined to occur at adsorbent weight of 20 to 40 g in most conditions.

Adsorption Behavior of Low Concentration Phosphorus from Water onto Modified Reed Biochar

In order to remove low concentration of phosphorus in wastewater and realize resource utilization of reed, reed biochar(RB) was prepared using reed and then modified by ferric chloride, and the adsorption behavior of low concentration phosphorus was investigated. The results showed that the iron content of modified reed biochar(MRB) was 11.98 mg·g-1, which was 44.7 times that of RB; pHpzc of the MRB was 7.49, and the adsorption effect was the best when the solution pH was 7.0; at the initial concentration of 4.0 mg·L-1 and temperature of 298K, the adsorption capacity of MRB was 0.658 mg·g-1, which was 34.6 times that of RB. The adsorption isotherms at different temperatures were well fitted to Langmiur equation, which indicated the adsorption was monolayer adsorption, and increasing temperature was favorable for adsorption. ΔGθ<0, ΔHθ>0 and ΔSθ>0 indicated that the adsorption was a spontaneous, entropy increasing and endothermic process. The kinetic experimental data of the adsorption fitted well to the pseudo-second-order equation, the initial adsorption rate increased with the increasing initial concentration of solution, and the adsorption was mainly controlled by intraparticle diffusion. The research will provide basic data for application of MRB in deep removal of low concentration phosphorus from sewage treatment plant and water body.

Microwave-Ferrous Sulfate Modified Activated Carbon Adsorption Study on Phosphorus Removal

Using microwave-ferrous sulfate modified activated carbon adsorption manner to remove the high concentration of phosphorus in wastewater. The power of microwavethe concentration of ferrous sulfate and reaction time on phosphorus removal were studied. When the power of microwave was 425W,the concentration of ferrous sulfate was 0.1mol/L,reaction time was 50 min,the removal rate of TP reaches 95.67%,the treated effluent TP can be dropped to 0.48mg/L,the TP can reaches the first effluent standard of TP in the comprehensive wastewater discharge standard (GB8978-1996).Microwave-ferrous sulfate modified activated carbon is adapted to treat high concentration phosphorus in the wastewater.

Phosphorus removal using nanofiltration membranes

A high concentration of phosphorus in wastewater may lead to excessive algae growth and deoxygenation of the water. In this work, nanofiltration (NF) of phosphorus-rich solutions is studied in order to investigate its potential in removing and recycling phosphorus. Wastewater samples from a pulp and paper plant were first analyzed. Commercial membranes (DK5, MPF34, NF90, NF270, NF200) were characterized and tested in permeability and phosphorus removal experiments. NF90 membranes offer the highest rejection of phosphorus; a rejection of more than 70% phosphorus was achieved for a feed containing 2.5 g/L of phosphorus at a pH <2. Additionally, NF90, NF200 and NF270 membranes show higher permeability than DK5 and MPF34 membranes. The separation performance of NF90 is slightly affected by phosphorus concentration and pressure, which may be due to concentration polarization and fouling. By adjusting the pH to 2 or adding sulfuric acid, the separation performance of NF90 was improved in removing phosphorus. However, the presence of acetic acid significantly impairs the rejection of phosphorus.