Suspended Solids In Wastewater Research Articles

Post-treatment of high-rate activated sludge effluent via zeolite adsorption and recovery of ammonium-nitrogen as alternative fertilising products

This study investigates the potential to connect nutrient flows between wastewater treatment and agriculture through a two-stage nitrogen (N) recovery system composed of high-rate activated sludge treatment in contact stabilisation mode (HRAS/CS) and column adsorption with zeolite. The HRAS/CS process removes organic matter and suspended solids in wastewater, leaving N behind in the effluent. The N was successfully recovered with the zeolite column under different scenarios, generating N and K-rich by-products. The regeneration effluent from the zeolite column with KCl contained 60–845 mg NH4+-N/L and 1.6–14.3 g K/L, having potential for use as fertigation water. The N-saturated zeolite contained 1.5–8.4 mg N/g and 14.3–19.3 mg K/g of the product fresh weight and low contaminant content, making it potentially eligible as various fertilising products. Adsorption can thus concentrate N from HRAS/CS effluent and produce by-products with potential agricultural value while meeting chemical oxygen demand and total nitrogen discharge standards.

Research on an eco-safe filtration plant for wastewater treatment made of natural raw materials

Purpose. To develop a new eco-safe filtration plant for wastewater treatment based on natural and secondary raw materials, which will allow rational use of natural resources with further mathematical modeling of hydrodynamics of mixing treated wastewater in bioponds to predict removal of residual concentrations from the filter. Methodology. A complex of modern methods of theoretical and experimental research was used to solve the tasks. Concentration of pollutants was determined using methods of atomic adsorption spectroscopy, titrimetry and gravimetric methods, as well as pyrometric analysis. A laboratory installation was created, which included a receiving tank, a filter column, and a tank for collecting purified wastewater. Prediction of distribution and mixing of treated effluent in bioponds was carried out using mathematical and computer software. Findings. An environmentally safe filtration plant (containing sand, fallen leaves of linden, poplar, and plastic residues separated by a polymer mesh) was created to purify wastewater from suspended substances and nitrates. Kinetics of changes in concentration of suspended solids and nitrates in urban wastewater were studied. When using the filtration plant, concentration of suspended solids decreased by 85–92 %. Concentration of nitrates in purified water processed with such a plant is reduced from 12 to 0.25–0.05 mg/dm3. A mathematical model concerning distribution of purified water in a biopond was obtained, which allows predicting possible migration distributions of residual concentrations in purified water during its natural movement downstream. Originality. For the first time, influence of the species origin of fallen leaves on the performance indicators of wastewater filtration plant of urban sewage treatment constructions was investigated, which made it possible to substantiate a new way of disposal of this type of waste. For the first time, it was established that wastewater treatment using an eco-safe filtration plant based on natural and secondary raw materials, containing layers of sand, fallen oak, linden, and poplar leaves, gives an opportunity to reduce contents of suspended solids in wastewater by 1.5 times of the maximum permissible concentration; and such treatment also reduces concentration of nitrates by 4 times from the initial level. Pollutants from wastewater are mechanically fixed in pockets (microcracks, cracks) of fallen leaves, formed during drying of leaves, which is explained by hardening of intercellular spaces with formation of a specific geometry of holes. For the first time, mathematical modeling of purified wastewater movement in a biological pond with a complex geometry was performed, which allows estimating the concentration of the pollutant at its outlet from the pond. Practical value. The created environmentally safe wastewater filtration plant gives an opportunity to perform not only filtering, but also an effective biological purification of wastewater from nitrates on the surface of layers of fallen leaves. The wide use of the proposed installation will allow attracting plastic of polyethylene bottles used in everyday life as a secondary raw material. Based on the proposed mathematical model of movement of purified liquid containing residual concentrations of pollutants, it is possible to carry out qualitative forecasting and optimization of the process of cascade wastewater treatment at industrial and economic enterprises.

Unravelling the reason for seasonality of foaming in sewage-fed urban lakes

Foaming surface waters are a global phenomenon but are understudied. Bellandur lake in India has gained international attention due to its foaming events, which occur seasonally after rainfall. This study investigates the seasonality of foaming and the sorption/desorption of surfactants onto sediment and suspended solids (SS). Results show that foaming lake sediment can contain as much as 3.4 g of anionic surfactant/ kg of dry sediment, and its concentration was proportional to the organic matter (OM) content and surface area of the sediment sample. This is the first study to demonstrate the sorption capacity of SS in wastewater, which was found to be 53.5 ± 4 mg surfactant/g SS. In contrast, only a maximum of 5.3 mg surfactant was sorbed/g of sediment. The lake model analysis revealed that sorption is a first-order process and that surfactant sorption on SS and sediment is reversible. SS was found to desorb ∼73 % of sorbed surfactant back to the bulk water, while sediment desorbed 33–61 % of sorbed surfactants proportional to their OM. Contrary to the common assumption, rain does not dilute the surfactant concentration but instead increases the foaming potential of lake water through desorption from SS.

Mathematical modeling of wastewater treatment facilities of transport enterprises

Wastewater is purified by mechanical, biological, physicochemical and chemical methods. Mechanical treatment plants are the main stage of treatment and remove most of the harmful substances contained in wastewater. The mechanical treatment facilities include a sand trap, a sump, a hydrocyclone, a grid, etc. Among them, the most common and basic design are sumps, which are divided into types according to design and function. In this article, a new mathematical model for calculating vertical sediments used in local treatment for small enterprises has been improved, and design parameters have been calculated. Theoretical studies of the proposed sump were carried out on the basis of molecular kinetic theory, and its accuracy was verified by the author in experimental tests. In the sump, an expression for the distribution of the concentration of suspended solids in wastewater was found. Thus, a filter structure with a filtration efficiency above 60% was created.

A comparison of precipitation and filtration-based SARS-CoV-2 recovery methods and the influence of temperature, turbidity, and surfactant load in urban wastewater

Wastewater-based epidemiology (WBE) has become a complimentary surveillance tool during the SARS-CoV-2 pandemic. Viral concentration methods from wastewater are still being optimised and compared, whilst viral recovery under different wastewater characteristics and storage temperatures remains poorly understood. Using urban wastewater samples, we tested three viral concentration methods; polyethylene glycol precipitation (PEG), ammonium sulphate precipitation (AS), and CP select™ InnovaPrep® (IP) ultrafiltration. We found no major difference in SARS-CoV-2 and faecal indicator virus (crAssphage) recovery from wastewater samples (n = 46) using these methods, PEG slightly (albeit non-significantly), outperformed AS and IP for SARS-CoV-2 detection, as a higher genome copies per litre (gc/l) was recorded for a larger proportion of samples. Next generation sequencing of 8 paired samples revealed non-significant differences in the quality of data between AS and IP, though IP data quality was slightly better and less variable. A controlled experiment assessed the impact of wastewater suspended solids (turbidity; 0–400 NTU), surfactant load (0–200 mg/l), and storage temperature (5–20 °C) on viral recovery using the AS and IP methods. SARS-CoV-2 recoveries were >20% with AS and <10% with IP in turbid samples, whilst viral recoveries for samples with additional surfactant were between 0–18% for AS and 0–5% for IP. Turbidity and sample storage temperature combined had no significant effect on SARS-CoV-2 recovery (p > 0.05), whilst surfactant and storage temperature combined were significant negative correlates (p < 0.001 and p < 0.05, respectively). In conclusion, our results show that choice of methodology had small effect on viral recovery of SARS-CoV-2 and crAssphage in wastewater samples within this study. In contrast, sample turbidity, storage temperature, and surfactant load did affect viral recovery, highlighting the need for careful consideration of the viral concentration methodology used when working with wastewater samples.

Development of a reproducible method for monitoring SARS-CoV-2 in wastewater

Monitoring the genetic signal of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) through RNA titers in wastewater has emerged as a promising strategy for tracking community-scale prevalence of coronavirus disease 2019 (COVID-19). Although many studies of SARS-CoV-2 in wastewater have been conducted around the world, a uniform procedure for concentrating the virus in wastewater is lacking. The goal of this study was to comprehensively evaluate how different methods for concentrating the suspended solids in wastewater affect the associated SARS-CoV-2 RNA signal and the time required for processing samples for wastewater-based epidemiology efforts. We additionally consider the effects of sampling location in the wastewater treatment train (i.e., following preliminary or primary treatment), pasteurization, and RNA extraction method. Comparison of the liquid phase to suspended solids obtained via centrifugation or vacuum filtration suggests that the RNA signal of SARS-CoV-2 preferentially occurs in the solids. Therefore, we assert that the recovery of SARS-CoV-2 from wastewater should focus on suspended solids. Our data indicate that the measured SARS-CoV-2 signal is higher among samples taken from the primary clarifier effluent, as opposed to those taken after preliminary treatment. Additionally, we provide evidence that sample pasteurization at 60 °C for 90 min reduces the SARS-CoV-2 signal by approximately 50-55%. Finally, the results indicate that a magnetic bead approach to RNA extraction leads to a higher SARS-CoV-2 signal than does a silica membrane approach.

Application of Tamarindus indica seed extract as bio-coagulant to removal suspended solids and colors

The batik traditional industries in East Java, Indonesia generally not have a proper wastewater treatment plant yet, so liquid waste directly discharge into the river. Batik wastewater generally have a dark color, which derived from the coloring of naphthol with number of suspended solids greater than 100 mg/L and color concentration more than 250 Pt.Co. Tamarind seed extract is known to contain natural polyelectrolytes active group, which had function as bio-coagulant. The research objective was to analyze the application of tamarind seed extract as bio-coagulant in wastewater treatment of the Batik traditional industries, by reducing suspended solids levels and color of wastewater. The research design used pretest and posttest control group design with variations of bio-coagulant doses of 10ml/L, 30ml/L, and 50ml/L, and analyzed using the Two Way Anova Test. The results showed that the level of suspended solids in wastewater before treatment averaged 291mg/L, and the average color content was 593 Pt-Co, so it did not meet the quality standards of the Governor of East Java No 72/2013. For the highest reduction in suspended solids levels at a dose of 10ml/L reduced up to 95.1% and the highest decrease in color levels at a dose of 50ml/L, reduced up to 87.8%. Traditional batik wastewater treatment, which used a coagulation-flocculation process with bio-coagulant extract of tamarind seeds could reduce levels of suspended solids and colors, in order to meet the specified quality standards.

Wastewater Treatment on Shrimp Processing Industry

Increasingly rapid industrial development poses serious environmental problems such as wastewater.The higher the number of production, the more waste that wasted and can decrease the environment quality. Fieldwork practice activity is carried out starting from the date of January 20, 2014, until February 15, 2014. The purpose of this fieldwork practice is to acquire knowledge and skills on the field of wastewater treatment technique and to know the parameters of the wastewater inlet and outlet channels in comparison with wastewater quality standards. The method that used in Field Work Practice This is descriptive, the method to describe the circumstances or events in a particular region. The result obtained from fieldwork practice known that wastewater treatment techniques consist of preliminary treatment activities, primary treatment, secondary treatment, sedimentation, and disinfection. Preliminary treatment activities is a filtering process substantial in the wastewater that comes out of the inlet channel using four mesh size of the net. The primary treatment for separating solids that escaped from the screening process and disposed to wastewater reservoirs. Secondary treatment activity including Aerobacter sp., Nitrosomonas sp., Nitrobacter sp., Bacillus sp. of bacteria and oxygen addition inside of wastewater. Sedimentation phase separation process is carried out suspended solids in wastewater using clarifier pond. Disinfection stage which activities the addition of chlorine with 222 ppm of doses to kill harmful pathogens. The final stage test to determine the parameters of wastewater effluent quality by using living fishes and taking the sample from another institution.

Purifying agents for produced fluid from chemical flooding in conventional and heavy oil reservoirs

Compared with water flooding, the produced wastewater quality of polymer flooding and ASP flooding has changed significantly. The effect of chemical flooding agent on the stability and purification process of oil droplets and suspended solids in wastewater was analyzed. The two-stage sedimentation-pressure filtration process and the continuous batch sedimentation-two-stage filtration process used in the treatment of chemical flooding wastewater are introduced. The application of organic flocculants, inorganic flocculants, reverse demulsifiers, chemical desiliconizing agents and other purifying agents in the treatment of chemical flooding wastewater is summarized. The key research directions of wastewater treatment from chemical flooding in the future are put forward.

Specific interactions of rotavirus HAL1166 with Enterobacter cloacae SENG-6 and their contribution on rotavirus HAL1166 removal.

Contribution of specific interactions between human enteric viruses and wastewater suspended solids on human enteric virus removal by microfiltration was studied. A cross-flow microfiltration system was used with rotavirus HAL1166 and Enterobacter cloacae SENG-6 as the model virus and wastewater suspended solid. Cleavage of rotavirus HAL1166 protein VP4 by trypsin produces the VP8* subunit, which specifically interacts with histo-blood group antigen (HBGA). In the presence of Enterobacter cloacae SENG-6, the trypsin-treated rotavirus concentration reduced with time (R2 > 0.6) compared to the reduction of non-trypsin treated rotavirus. Calculation of the gel/cake layer deposited on the membrane, consisting of Enterobacter cloacae SENG-6 and either trypsin-treated or non-trypsin treated rotavirus HAL1166, revealed that the microflocs consisting of trypsin-treated rotavirus and Enterobacter cloacae SENG-6 have lower porosity and permeability, displaying higher resistance to virus passage through the membrane. The results provide evidence that specific wastewater suspended solids-human enteric virus interaction can contribute to increasing the removal of human enteric viruses by microfiltration.

The efficiency and reliability of pollutant removal in a hybrid constructed wetland with giant miscanthus and Jerusalem artichoke in Poland

In this paper, we analysed the pollutant removal efficiency and reliability of a vertical and horizontal flow hybrid constructed wetland (CW) planted with giant miscanthus and Jerusalem artichoke. The wastewater treatment plant, located in south-eastern Poland, treated domestic sewage at an average flow rate of 1.2 m3·d−1. The tests were carried out during. 5-years of operation of the sewage treatment plant (2011–2016). During this period, sewage samples were collected from three stages of wastewater treatment in four seasons (winter – February, spring – May, summer – August, and autumn – November). The following parameters were measured: BOD5, COD, total suspended solids, total nitrogen, and total phosphorus. The average effectiveness of organic pollutant removal expressed by BOD5 and COD was 98.8 and 97.6%, respectively, and the removal efficiency for total suspended solids was 93%. The average values of BOD5, COD, and total suspended solids in wastewater discharged to the receiver were significantly lower than the limit values required in Poland. The efficiency of total nitrogen and total phosphorus removal was 64.1 and 68.1%, respectively, and the average values of these components in the outflow from the treatment plant exceeded the standard levels. A reliability analysis performed using the Weibull probability model showed that the reliability of pollutant removal in the tested CW system was very high for BOD5 and COD (100%). It was also demonstrated that the tested CW did not provide effective elimination of biogenic elements (nitrogen and phosphorus), as evidenced by the low reliability values – 32 and 28%, respectively. The investigated hybrid CW system with giant miscanthus and Jerusalem artichoke removed organic and biogenic pollutants with a similar efficiency as systems using classic plant species such as reed and willow.

Application of PAC and flocculants for improving settling of solid particles in oilfield wastewater with high salinity and Ca2.

The suspended solids in wastewater from Rekabak oilfield, Kazakhstan, were characterized and treated with flocculants to enhance settling. The wastewater contained a high concentration of total dissolved solids and calcium ion. Scanning electron microscopy and energy dispersive X-ray analyses showed that suspended solids were mainly composed of corrosion products (iron oxides) and silicon dioxide particles. Also, much salt deposition from wastewater caused a large increase in the suspended solids value. The settling of solid particles in wastewater was investigated by turbidity decrease within 60 min. The particle settling was enhanced by adding polyaluminum chloride (PAC) as coagulant and hydrolyzed polyacryamide (HPAM) or cationic polyacrylamide (CPAM) as flocculant. At optimal dose, the particle settling ability with PAC and CPAM was better than that with PAC and HPAM. Particle size analysis showed that HPAM or CPAM with high molecular weight played an important role for enlarging the particle size. The experiments with simulated wastewater showed that particle settling by using HPAM deteriorated significantly compared to that by CPAM at high calcium ion. This study provides further understanding about the effect of high salinity and Ca2+ on solids formation, flocculant performance and particle settling. Meanwhile, the results are also helpful to develop novel flocculants used for high salinity wastewater.

Comparing peracetic acid and hypochlorite for disinfection of combined sewer overflows: Effects of suspended-solids and pH

Peracetic acid (PAA) is an alternative disinfectant that may be effective for combined sewer overflow (CSO) disinfection, but little is known about the effect of particle size on PAA disinfection efficiency. In this work, PAA and hypochlorite were compared as disinfectants, with a focus on the effect of wastewater particles. Inactivation experiments were conducted on suspended cultures of Escherichia coli and wastewater suspended solids. Tested size fractions included particle diameters <10μm, <100μm, and raw wastewater. Chlorine disinfection efficiency decreased with increasing solids size. However, solids size had little effect on PAA disinfection. The PAA disinfection efficiency decreased at pH values above 7.5. Live/dead staining revealed that PAA disinfection leaves most cells in a viable but non-culturable condition. Fourier transform infrared spectroscopy (FTIR) analyses suggests that PAA and hypochlorite may inactivate E. coli bacteria by similar mechanisms.

The changes in the physical and hydraulic properties of a loamy soil under irrigation with simpler-reclaimed wastewaters

Soil physical properties (bulk density, particle density, total porosity, pore size distribution and aggregate stability) and hydraulic properties (water retention and infiltration) may be affected significantly from wastewater irrigation. In addition, environmental conditions may change the magnitude of these effects. Therefore, we examined the effects of irrigation with simpler-reclaimed wastewaters on the certain soil properties under cauliflower and red cabbage planting with two-year study in a semi-arid region with a cool climate. W1 (filtered wastewater), W2 (filtered and aerated wastewater) and W1-FW (mix of filtered wastewater with the freshwater at the ratio of 1:1 as volume) were the wastewater treatments. Control plots were irrigated with freshwater (FW) provided from groundwater.Soil electrical conductivity and organic C content in wastewater irrigated plots were higher than the freshwater irrigated plots. Moreover, exchangeable sodium percentage was low in wastewater plots (<2.25%). Therefore, irrigation with especially W1 and W2 wastewaters markedly increased the aggregate stability. Particle density was not changed with wastewater applications. Although bulk density and porosity increased under the wastewater irrigation conditions, changes were not meaningful in terms of practical conditions. While available soil moisture increased with the increase of micropores, infiltration rate decreased with the decrease of macropores. This was probably because of the clogging of pores with suspended solids in wastewater. According to research findings, it was expressed that soil aggregation and available water content could be improved under irrigation with the mix of filtered wastewater and freshwater in a semi-arid region with a cool climate and the infiltration rate could also be protected.

Application of Single Angle Turbidimetry on Coag-Flocculation Effect of &amp;lt;i&amp;gt;Detarium microcarpum&amp;lt;/i&amp;gt; Seed in Brewery Effluent

Coagulation-flocculation is a proven technique for the removal of suspended solids in wastewater, through the application of single angle turbidimetric measurement. Through this measurement, the coag-flocculation kinetics and functional parameters behavior of Detarium microcarpumin brewery effluent with respect to pH, dosage and time were followed at room temperature. Process parameters such as order of reaction α, rate constant (K), coagulation period τ1/2 etc were determined. Results indicated that reaction order, rate constant, period, pH and dosage recorded optimum values at 2, 1.8 × 10-2 L/mg.min, 0.152 min, 4 and 100 mg/L, respectively. Maximum efficiency recorded was 96.07% at 30 min. Detarium microcarpum has shown potential as an effective bio-coagulant for the removal of turbidity from brewery effluent.

The contribution of suspended solids to municipal wastewater PHA-based denitrification

The role of wastewater suspended solids in denitrification based on intracellular carbon storage was investigated in a biofilm sequencing batch reactor performing alternately anaerobic carbon storage and denitrification. Municipal wastewater as the feeding was compared with filtered wastewater and with acetate. The results show that the amount of PHA (polyhydroxyalkanoates) stored during a cycle was quite similar, irrespective of the substrate type used as feeding (acetate, real wastewater and real wastewater after filtration). PHA storage was limited even under excess chemical oxygen demand (COD) conditions, with a reducing power capacity enough for denitrification of only 25–26 mg/L N. However, when non-filtered wastewater was used, the denitrification capacity was about 50% higher (38 mg/L N) due to the contribution of entrapped suspended solids as the electron donor. In addition, the involvement of the hydrolyzed wastewater suspended solids resulted in a different PHA composition containing a much higher poly-3-hydroxyvalerate content.

Predicting the total suspended solids in wastewater

Total suspended solids (TSS) are a major pollutant that affects waterways all over the world. Predicting the values of TSS is of interest to quality control of wastewater processing. Due to infrequ...

Predicting the total suspended solids in wastewater: A data-mining approach

Total suspended solids (TSS) are a major pollutant that affects waterways all over the world. Predicting the values of TSS is of interest to quality control of wastewater processing. Due to infrequent measurements, time series data for TSS are constructed using influent flow rate and influent carbonaceous bio-chemical oxygen demand (CBOD). We investigated different scenarios of daily average influent CBOD and influent flow rate measured at 15min intervals. Then, we used five data-mining algorithms, i.e., multi-layered perceptron, k-nearest neighbor, multi-variate adaptive regression spline, support vector machine, and random forest, to construct day-ahead, time-series prediction models for TSS. Historical TSS values were used as input parameters to predict current and future values of TSS. A sliding-window approach was used to improve the results of the predictions.

Suspended solids settling and half removal time in stabilization ponds (Tunisia)

Settling is one of the processes occurring in waste stabilization ponds (WSP). Part of suspended solids (SS) is removed by sedimentation but very often the efficiency of WSP is presented without making a difference between settling and biological processes. In this way the WSP is seen as a black box process. This work presents an experimental approach to the study of the removal of wastewater suspended solids in a test column in order to improve our knowledge of the settling process in ponds. These results show that the settling test in columns can be used to estimate the half removal time (t50) for the study of settling characteristics of suspended solids in wastewater stabilization ponds. The aim of this study was to determine the half removal time (t50) in anaerobic, facultative and maturation ponds, and in the influent to these ponds, at the experimental wastewater treatment plant of CERTE (Recycling and Treatment Center of Wastewater in Tunisia), by a column settling test. The experiments lasted between 15 and 120 min. The column was 2 m high with sampling systems at various depths: 40, 80, 120, 160 and 200 cm. Half-removal suspended solids time t50 was defined as the time at which 50% of SS was removed. Models derived from the scientific literature were used to interpret the experimental data. The experimental results demonstrated that higher suspended solids concentrations in the influent led to shorter t50 values and better settling.

Effects of wastewater application on saturated hydraulic conductivity of different soil textures

AbstractAs metropolitan areas expand, the municipal and industrial uses of freshwater increase. Therefore, water resources for irrigation become limited and wastewater reuse for irrigation becomes a good alternative. For this purpose, the effects of suspended solids in wastewater on the soil physical properties, i.e., saturated hydraulic conductivity, Ks, have to be considered. The objectives of this research were to study the effects of applying freshwater and differently treated wastewater on Ks in the surface and subsurface layers of sandy‐loam, loam, and clay‐loam soils. This effect was studied by investigating the ratio of Ks for wastewater to Ks for fresh water in soil surface as Kr1 and in soil subsurface as Kr2. The results showed that the application of freshwater did not reduce the Kr1 considerably. However, the reduction in Kr1 mainly occurred in soil depth of 0–50 mm due to the application of wastewater. This effect is more pronounced in clay‐loam soil than in loam and sandy‐loam soils. It is concluded that application of wastewater with TSS (total suspended solid) of ≥ 40 mg L–1 resulted in Kr1 reduction of &gt;50% in different soil textures. However, the Kr2 reduction at soil depth of 100–300 mm is not considerable by application of wastewater for different soil textures. Further, it is concluded that less purified wastewater can be used in light‐texture soils resulting in less reduction in Kr1. Empirical models were developed for predicting the value of Kr1 as a function of amounts of wastewater application and TSS for different soil textures that can be used in management of wastewater application for preventing deterioration of soil hydraulic conductivity.