Effects Of Total Suspended Solids Research Articles

The effect of total suspended solids on the nursery of Penaeus vannamei nauplius based on biofloc technology system

A 14-day study was carried out to investigate the nursery of the nauplius (N5) Penaeus vannamei in biofloc technology (BFT) system. The whole experiment was divided into three groups: the control group (GC) without bioflocs, T300 and T600 with bioflocs in which total suspended solid (TSS) levels were maintained at 300 and 600 mg/L, respectively. The results revealed that the average total ammonia nitrogen (TAN) levels in GC were significantly higher than those in T300 and T600 (p < 0.05). By contrast, the nitrite of T300 was significantly higher than the other groups (p < 0.05). Nitrate and total nitrogen (TN) were increased with the increasing TSS, whereas alkalinity and pH decreased. The higher dry weight was detected in T300, and the survival rate under salinity stress was also significantly higher than the T600 (p < 0.05). Besides, there was no significant difference in the total Vibrio bacteria (TVB) and body length of the shrimp among all groups (p > 0.05). In conclusion, BFT with the TSS level <300 mg/L can achieve better performance in P. vannamei of nauplius nursery.

Effect of phosphate and ammonium concentrations, total suspended solids and alkalinity on lignin-induced struvite precipitation

To solve the problems of eutrophication and resource crisis, the recovery of phosphorus by struvite (NH4MgPO4·6H2O) precipitation has become a focus of recent research. The feasibility of using Kraft lignin powder as a seed to promote struvite precipitation has been demonstrated in the previous study. In this study, the effect of lignin in promoting struvite precipitation in synthetic wastewater with different characteristics was investigated. Lignin-induced struvite crystallization was tested under various initial concentrations of PO4–P and NH4–N, total suspended solids (TSS) and alkalinity. At pH 7.9, the enhancement of PO4–P recovery remains around 45% under different PO4–P and NH4–N concentrations. Moreover, lignin is more effective under relatively lower alkalinity and still workable to reduce co-precipitates potential under higher alkalinity. Also, the effect of TSS on PO4–P recovery is not significant. Overall, the effect of lignin in promoting phosphorus recovery is relatively stable and can be used in synthetic wastewater with different characteristics.

The Effect of Total Suspended Solids on the Electricity Generation in Microbial Fuel Cell Treating Actual Potato Chips Processing Wastewater

This study aimed to investigate the effect of total suspended solids (TSS) on the performance of a continuously operated dual-chamber microbial fuel cell (MFC) proceeded by primary clarifier to treat actual potato chips processing wastewater. The system was also tested in the absence of the primary clarifier and the results demonstrated a significant effect of TSS on the polarization curve of the MFC which was obtained by operating the graphite anodic electrode against Ag/AgCl reference electrode. The maximum observed power and current densities were decreased form 102.42 mW/m2 and 447.26 mA/m2 to 80.16 mW/m2 and 299.10 mA/m2, respectively due to the adverse effect of TSS. Also, the internal resistance increased from 40 to 70Ω.&#x0D;

Effects of total suspended solids, particle size, and effluent temperature on the kinetics of peracetic acid decomposition in municipal wastewater.

In this study, the influence of total suspended solids (TSS) and particle size as well as effluent temperature on peracetic acid (PAA) decomposition kinetics in municipal wastewater was investigated. PAA decomposition was best described following second order kinetics in primary effluent (PE) and first order kinetics in secondary effluent (SE) samples. For synthetic samples prepared by varying TSS levels, PAA demand increased on average by about 0.042 mg/L in PE and 0.034 mg/L in SE for every 10 mg/L increase in TSS. Similarly, the PAA decay rate constant in these samples increased at a rate of 0.0014 L/mg.min and 0.00039 min-1, respectively, per 10 mg/L TSS. To examine the effect of particle size, synthetic samples with narrow size fractions (20-45, 45-75, and 75-90 μm) were prepared. It was found that samples with smaller particle size fractions had a greater PAA demand and decay rate constant. Effluent temperature also enhanced the PAA decomposition rate with the calculated activation energies for PE and SE samples being 29,980 J/mol and 34,860 J/mol, respectively.

Living the high turbidity life: The effects of total suspended solids, flow, and gill morphology on mussel feeding

AbstractUnionid mussels from clear‐water rivers are often found in turbid waters in which their feeding and reproductive efficiency should be impaired. We examined the feeding response of Lampsilis siliquoidea from a clear and turbid river in response to increased concentrations of total suspended solids (TSS) and water velocity in a funnel chamber and a recirculating flow chamber. Four TSS concentrations (0, 5, 20, and 100 mg L−1) and four velocities (0, 0.05, 0.15, and 0.25 m s−1) were used to create 16 experimental conditions corresponding to nine TSS flux (concentration × velocity) levels. TSS flux significantly affected clearance rates (CR); however, the relationship was complex. Increased TSS led to lower CR in mussels from clear and turbid river at all velocities; however, increases in velocity reduced the magnitude of the decline with respect to TSS. Overall, the turbid river mussels were less affected by increased TSS than those from the clear‐water rivers. The mussels from the turbid river also differed anatomically (i.e., greater palp:gill ratio; number of cilia per cirri; number of cirri cm−1; and thickness of palp cilia, and less cilia per unit area of palp) from the clear river animals. It is likely that these anatomical differences allow the mussels to feed more efficiently in turbid water, which explains the observed differences in CR response to TSS. These results demonstrate the importance of multistressor approaches in evaluating aquatic organisms, as well as providing a potential mechanism to explain how mussels thrive in turbid rivers.

Effect of suspended solids on peracetic acid decay and bacterial inactivation kinetics: Experimental assessment and definition of predictive models

The work addresses the effect of total suspended solids (TSS) on disinfection by peracetic acid (PAA) concerning both PAA decay and bacterial inactivation kinetics. The effect of TSS on PAA decay was evaluated at five TSS concentrations (5, 40, 80, 120 and 160 mg/L), obtained from stock TSS solutions prepared from activated sludge samples. The influence of the soluble matter associated to the suspended solids on PAA decay was evaluated separately, using the same stock TSS solution after the removal of solids by filtration. The contributions of suspended and soluble fractions were found to be independent, and a predictive model formed by two additive sub-models was proposed to describe the overall PAA decay kinetics. Moreover, an uncertainty analysis was performed by a series of Monte Carlo simulations to propagate the uncertainties associated to the coefficients of the model. Then, the disinfectant dose (mg/L min) was highlighted as the main parameter determining disinfection efficiency on a pure culture of E. coli and an inactivation kinetic model was developed based on the response of E. coli to various PAA doses. Finally, the effect of TSS (40 and 160 mg/L) on the inactivation of free-swimming E. coli was investigated at two PAA doses (5 and 20 mg/L min). TSS reduced inactivation extent an average of 0.4 logs at 5 mg/L min and 1.5 logs at 20 mg/L min. It was hypothesized that this might be due to the formation of bacteria aggregates as defense mechanism against disinfection, enhanced by the presence of solids.

Effect of total suspended solids and various treatment on rheological characteristics of municipal sludge

Rheological characteristics play an important role in the design and optimization of sludge treatment processes that are dependent on the total suspended solids (TSS). The present study systematically investigated the impact of various treatment processes on sludge rheology. The effect of TSS on rheological properties was comprehensively explored. Rheological tests were performed at (20 ± 0.1) °C, physicochemical parameters of the sludge were measured for compositional analysis. The composition of sludge is altered when subjected to both heat treatment and AD. All sludges exhibit shear-thinning behavior, the results of a t test (with significance level of 0.05) indicated that the Herschel–Bulkley model provides a valid description of sludge flow behaviors. The anaerobically digested sludge (ADS) is the least viscous while thermal hydrolyzed sludge (THS) shows slightly higher viscosity than that of fresh mixed sludge (FMS) at high shear rates. The yield stress and thixotropy decrease gradually as the treatment proceeds. Both infinite viscosity and yield stress of THS increases dramatically when the TSS exceeds 7.30%, hence 7.30% may serve as a critical level for THS to preliminarily determine whether it is economically viable to implement a thermal pretreatment. The TSS threshold for ADS is determined to be 7.12% given the sharp increase in infinite viscosity and yield stress, which are undesirable for dewatering. The thixotropy increases with increasing TSS, and TSS only has a slight influence on the thixotropic properties of THS relative to FMS, which demonstrates the advantage of thermal pretreatment for the purpose of achieving high solid sludge AD.

Total Suspended Solids Effects on Freshwater Lake Biota Other than Fish

Protective benchmarks for the effects of total suspended solids (TSS) on freshwater aquatic biota primarily focus on fish; whether these benchmarks will also protect their prey or co-existing lower trophic level aquatic biota was uncertain. We conducted an extensive literature review of TSS effects on those organisms comprising the food webs upon which fish living in lakes depend: phytoplankton, zooplankton, periphyton, and benthic invertebrates. The available literature indicates that TSS benchmarks that protect sensitive life stages of lake fish will also protect their supporting food webs; in other words, the function of lake aquatic communities will be protected and maintained.

Multivariate analysis of sludge disintegration by microwave–hydrogen peroxide pretreatment process

Microwave irradiation (with H2O2) has been shown to offer considerable advantages owing to its flexible control, low overall cost, and resulting higher soluble chemical oxygen demand (SCOD); accordingly, the method has been proposed recently as a means of improving sludge disintegration. However, the key factor controlling this sludge pretreatment process, pH, has received insufficient attention to date. To address this, the response surface approach (central composite design) was applied to evaluate the effects of total suspended solids (TSS, 2–20g/L), pH (4–10), and H2O2 dosage (0–2w/w) and their interactions on 16 response variables (e.g., SCODreleased, pH, H2O2remaining). The results demonstrated that all three factors affect sludge disintegration significantly, and no pronounced interactions between response variables were observed during disintegration, except for three variables (TCOD, TSSremaining, and H2O2 remaining). Quadratic predictive models were constructed for all 16 response variables (R2: 0.871–0.991). Taking soluble chemical oxygen demand (SCOD) as an example, the model and coefficients derived above were able to predict the performance of microwave pretreatment (enhanced by H2O2 and pH adjustment) from previously published studies. The predictive models developed were able to optimize the treatment process for multiple disintegration objectives.

Removal of nitrogen by Algal Turf Scrubber Technology in recirculating aquaculture system

Ongoing research in recirculation aquaculture focuses on evaluating and improving the purification potential of different types of filters. Algal Turf Scrubber (ATS) are special as they combine sedimentation and biofiltration. An ATS was subjected to high nutrient loads of catfish effluent to examine the effect of total suspended solids (TSS), sludge accumulation and nutrient loading rate on total ammonia nitrogen (TAN), nitrite and nitrate removal. Nutrient removal rates were not affected at TSS concentration of up to 0.08 g L−1 (P > 0.05). TAN removal rate was higher (0.656 ± 0.088 g m−² day−1 TAN) in young biofilm than (0.302 ± 0.098 g m−² day−1 TAN) in mature biofilm at loading rates of 3.81 and 3.76 g m−² day−1 TAN (P < 0.05), respectively, which were considered close to maximum loading. TAN removal increased with TAN loading, which increased with hydraulic loading rate. There was no significant difference in removal rate for both nitrite and nitrate between young and mature biofilms (P > 0.05). The ATS ably removed nitrogen at high rates from catfish effluent at high loading rates. ATS-based nitrogen removal exhibits high potential for use with high feed loads in intensive aquaculture.

A Coagulant Survey for Chemically Enhanced Primary Treatment of Synthetic CSOs

Combined sewer overflow (CSO) wastewaters tend to be highly variable in composition, presenting a challenge to effective treatment. The robustness of various coagulants and flocculants was studied in terms of their ability to bring about efficient contaminant removal under variable conditions. To accomplish this, the effects of total suspended solids (TSS) and dissolved organic carbon (DOC) concentrations on chemically enhanced settling of synthetic CSO wastewater were evaluated using various inorganic salt and organic polyelectrolyte products. The evaluated products varied in their responses to changes in solids and organics concentrations, particularly in terms of sensitivity to DOC concentration and ability to bring about its removal. The required dosages of the coagulants (both inorganic and organic) were quite sensitive to DOC concentration, but good to excellent TSS and DOC removals were obtained. In comparison, the polymer flocculants displayed good TSS removal but poor reduction of DOC under all conditions, in spite of sensitivity to initial DOC concentration. The coagulants and flocculants studied also varied in tendency to overdosing and effect on pH. While no coagulant or flocculant is universally applicable, understanding the trends in treatment efficiency can help in choosing the type of product that is most suitable for treatment under given wastewater quality conditions.

EAF Steel Slag Filters for Phosphorus Removal from Milk Parlor Effluent: The Effects of Solids Loading, Alternate Feeding Regimes and In-Series Design

Electric arc furnace (EAF) steel slag filters were investigated for their efficiency at reducing the concentration of phosphorus (P) from dairy farm wastewater in Vermont. The primary objective for this study was to examine the use of in series design on filters’ performance in P removal from dairy farm wastewater at subzero temperatures. Other research objectives were to investigate operational parameters such as the effects of total suspended solids (TSS) daily mass loading rates and of alternating feeding and resting periods on EAF steel slag filters’ TSS, dissolved reactive phosphorus (DRP) and total phosphorus (TP) removal efficiencies and filter system life-span. The utilization of in series filter design increased filter DRP removal efficiency by 35%. In series design also allows for alternating feeding and resting periods, which resulted in a 16%, 57% and 74% increase in TSS, DRP and TP removal efficiencies, respectively, by the first filter in series over a single period. Additionally, the system life span was extended 3.25 fold (from 52 to 169 day). Based on this research, we recommend alternate feeding and resting cycles and in series design to be integrated in the design of EAF steel slag filter systems for highly concentrated agricultural effluents in cold climates.

Total Suspended Solids and Flow Regime Effects on Periphyton Development in a Laboratory Channel

Flow regime and total suspended solids (TSS), along with chemical and biological parameters associated with urbanization and intensive agriculture/aquaculture, impact benthic organisms, which represents the food chain foundation in aquatic systems. We designed this experiment to begin the integration of physical flow regime effects along with chemical and biological indicators on periphyton, an important benthic organism indicator, towards a goal of using periphyton (live biomass containing chlorophyll a) and pheophytin (dead chlorophyll-containing biomass) in assessments of stream health. Physical flow regimes in a laboratory flume were created using multiple roughness conditions and an in-channel weir. Results suggested that one could model the hydraulic regime with a hydraulic model, HEC-RAS, to within 2% to 11% of measured velocity values. Thus, one may roughly but not precisely move computed velocities from the flume to the field. Significant interactions between biological response and hydraulic and TSS factors were observed, and the study suggested several indicators of periphyton-pheophytin response that are potentially relevant to ecological engineering applications featuring a channel. Increased mean velocities significantly reduced (P < 0.05) live periphyton and filament length. The 200 mg L-1 TSS level significantly reduced (P < 0.05) biomass and filament development. The effect of TSS was least where velocity was highest and depth was most shallow, which had the least effect on light absorption and resulted in the least sediment deposition. The intermediate TSS level (100 mg L-1) appeared to stimulate a growth response based on periphyton and filament length, although the effect was less noticeable where velocities were higher. Pheophytin tended to be highest in conditions resulting in lower periphyton values, consistent with the notion that regimes imparting physical stress would harbor the highest concentration of pheophytin. The periphyton/filament length ratio tended to be lowest in velocities less than 0.75 m s-1 except in the high TSS case, where both periphyton and filament length were low. Low velocities and low to moderate TSS would provide the most biomass for grazing organisms and would result in the most effective nutrient filtering due to long filament length. High periphyton/pheophytin ratios were associated with high TSS, velocities exceeding ~0.5 m s-1, or both. Sloughing could occur in systems with a pulsing velocity where the pulse period was long enough for growth to occur in the quiescent interval.

Variation in the Underwater Light Field under Simulated Water Current Conditions in Lake Taihu, China

ABSTRACT Under simulated water current conditions, we investigated the effects of total suspended solids (TSS) and chlorophyll a (chl a) on the diffuse attenuation coefficient and euphotic depth in Lake Taihu water. Photosynthetically available radiation (PAR) diffuse attenuation coefficients [Kd (PAR)] ranged from 1 to 2 and 4 m−1, with corresponding euphotic depths of 4.6, 2.3, and 1.15 m under still, slow, and fast water currents, respectively. The blue wavelength was the most strongly attenuated, and green was the most penetrating wavelength. The ranges of spectral diffuse attenuation coefficients from 400 to 700 nm were 0.75–2.56, 2.30–4.66, and 3.51 −10.34 m−1 under the three water currents. Significant correlations were found between Kd (PAR), euphotic depth [Zeu (PAR)], Secchi depth (SD) and TSS. However, TSS was the primary attenuation factor responsible for the observed differences in Kd , Zeu, and SD under conditions of different water current.

The Influence of Water Hardness, pH, and Suspended Solids on Nickel Toxicity to Larval Fathead Minnows (Pimephales promelas)

Nickel (Ni) is an ubiquitous, naturally occurring metalthat is associated with metal mining and other industrialactivities. Despite elevated Ni concentrations reportedfor many industrial receiving waters, Ni receives littleresearch attention addressing factors influencing itstoxicity to freshwater fish. This study examined theinfluence of water hardness, pH, and total suspended solids(TSS) in soft, reconstituted water on Ni toxicity to larvalfathead minnows (Pimephales promelas). Increasingwater hardness from 20 to 140 mg L-1 (as CaCO3) reduced acute Ni toxicity by 5-fold (96-h LC50s 0.45 and 2.27 mg Ni L-1, respectively). Low pH had a slight protective effect against Ni toxicity relative to neutral pH conditions. At pH 5.5, the 96-h LC50 was 0.69 mg Ni L-1, compared to 0.54 mg Ni L-1 at pH 7.0. However,Ni toxicity was significantly reduced at pH 8.5 where the 96-h LC50 was 2.21 mg Ni L-1. These results were explainedon the basis of Ni speciation. Total suspended solids also reduced Ni toxicity (expressed as 96-h LC50s) from 0.35 to 1.12 mg Ni L-1 over a TSS range of 10 to 100 mg L-1.This reduction of toxicity due to TSS is significant becausemine effluents often have a combination of elevated TSS andmetals. The ameliorative effect of TSS was not as significantas high hardness or pH probably because there is a TSS threshold, after which physical irritation to fish gills counteracts any protective effect conferred by TSS. This finding is relevant to choices made in design of mine effluenttreatment systems; i.e., there may be an optimum range ofTSS concentrations that protect aquatic biota againsteffects of metals that remain after treatment.

Long‐Term Temporal and Spatial Fluctuations of Soft Bottom Infaunal Invertebrates Associated with an Ocean Outfall from the San Pedro Shelf, California

AbstractTemporal (annual) and spatial fluctuations of soft‐bottom invertebrates from 1977 to 1988 were reviewed and analyzed from an ocean outfall area on the San Pedro Shelf, California. Several dominant species which occurred throughout the monitoring period provide continuity between early sampling efforts and recent ones. Annual fluctuations in the mean number of species, abundance, diversity and biomass were generally conservative compared to spatial fluctuations. Temporal changes of note include a marked reduction in abundance and biomass between 1981 and 1984 and another decline in biomass in 1988. The former was associated with conditions of the 1982–1983 El Niño, and the latter with a shift in population dominance from a bivalve to a polychaete.Mean abundance and biomass were enhanced by the outfall without a significant reduction in number of species. The response of the biota to the outfall extended further upcoast (northwest) than downcoast.Several hypotheses were posed and briefly examined. These include the effects of total suspended solids generated from the outfall, and the role of the “Three Little Pigs” (bivalve‐Parvilucina tenuisculpta CARPENTER, ostracod‐Euphilomedes carcharodonta (SMITH), polychaete‐Capitella capitata (FABRICIUS)) in influencing benthic community structure. Finally, measures of infauna from the San Pedro Shelf were, except for abundance, very similar to those reported from other California shelf areas. Through time and space the outfall has had limited negative effect on infaunal community structure.