scholarly journals PROBLEMS OF SOAPSTOCK TREATMENT OF VEGETABLE OIL PRODUCTIONS AND THEIR SOLUTIONS

2021 ◽  
Vol 14 (4) ◽  
pp. 80-87
Author(s):  
L. Sabliy ◽  

Wastewater generated during vegetable oil production contains various pollutants that enter it during soapstock processing: fats and fatty acids and their salts (aqueous soap solutions), glycerin, phosphoglycerates, neutral fat, phosphatides, proteins, carbohydrates, dyes, unsaponifiable and waxy substances, salts, mechanical impurities, etc. Aim. The purpose of the work was to study the processes of purification of industrial wastewater from oil production and to propose an effective technology for their treatment, taking into account the regulatory requirements for the discharge of treated wastewater into the city sewage system. Methods. Chemical oxygen demand (COD) was determined by the dichromate method. The concentration of suspended solids was determined by gravimetric method. Results. As a result of research, calcium carbonate was chosen as an alkaline reagent. After treatment of soapstock with calcium carbonate followed by flotation, the effect of removing the suspended particles was 70–75%, and COD decreased by 60%. On the basis of the research, a technology for processing soapstock was proposed, including sequential processes of physicochemical wastewater treatment —averaging, alkalization with calcium carbonate, stage I of flotation, coagulation, stage II of flotation, oxidation with hydrogen peroxide, filtration through quartz filters and adsorption on carbon filters. Conclusion. An effective technology for preliminary cleaning of the soapstocks oil production has been developed. This will significantly reduce the concentration of organic matter and other pollutants in soapstocks, which will significantly reduce the impact of such effluents on the processes of biological wastewater treatment of urban wastewater treatment plants.

2014 ◽  
Vol 80 (14) ◽  
pp. 4251-4259 ◽  
Author(s):  
Ibone Anza ◽  
Dolors Vidal ◽  
Celia Laguna ◽  
Sandra Díaz-Sánchez ◽  
Sergio Sánchez ◽  
...  

ABSTRACTDue to the scarcity of water resources in the “Mancha Húmeda” Biosphere Reserve, the use of treated wastewater has been proposed as a solution for the conservation of natural threatened floodplain wetlands. In addition, wastewater treatment plants of many villages pour their effluent into nearby natural lakes. We hypothesized that certain avian pathogens present in wastewater may cause avian mortalities which would trigger avian botulism outbreaks. With the aim of testing our hypothesis, 24 locations distributed in three wetlands, two that receive wastewater effluents and one serving as a control, were monitored during a year. Sediment, water, water bird feces, and invertebrates were collected for the detection of putative avian pathogenicEscherichia coli(APEC),Salmonellaspp.,Clostridium perfringenstype A, andClostridium botulinumtype C/D. Also, water and sediment physicochemical properties were determined. Overall, APEC,C. perfringens, andC. botulinumwere significantly more prevalent in samples belonging to the wetlands which receive wastewater. The occurrence of a botulism outbreak in one of the studied wetlands coincided with high water temperatures and sediment 5-day biochemical oxygen demand (BOD5), a decrease in water redox potential, chlorophylla, and sulfate levels, and an increase in water inorganic carbon levels. The presence ofC. botulinumin bird feces before the onset of the outbreak indicates that carrier birds exist and highlights the risk of botulinum toxin production in their carcasses if they die by other causes such as bacterial diseases, which are more probable in wastewater wetlands.


2020 ◽  
Vol 192 (11) ◽  
Author(s):  
Isaac Dennis Amoah ◽  
Sheena Kumari ◽  
Poovendhree Reddy ◽  
Thor Axel Stenström ◽  
Faizal Bux

AbstractThe quality of surface water could be influenced by both anthropogenic and natural factors. This study was designed to determine the impact of informal settlement and wastewater treatment plants on helminth egg contamination of urban rivers and the risks associated with everyday use. We also ascertained the accumulation of these eggs in the river sediments. The study was carried out in two rivers in the eThekwini Municipality of South Africa. Grab samples were taken at different points over a 10-month period. Ascaris spp., hookworm, Toxocara spp., Trichuris spp. and Taenia spp. were the helminth eggs detected in both the water column and sediments, with mean Ascaris spp. eggs of 0–6.3 (± 5.1)/L in the water and 0–6.8 (± 5.2)/kg in sediment samples. The helminth egg concentrations showed seasonal variation, probably due to changes in infection levels of the populations or natural factors, such as rainfall. The informal settlements had a greater impact than treated wastewater. For every 10,000 recreational users of the rivers 19 to 58 may be infected under undisturbed conditions, increasing to 29–88 individuals when the riverbed is disturbed. The risk from agricultural use of the rivers was above the tolerable risk values applicable for wastewater reuse, recommended by the World Health Organization. This calls for a re-evaluation of the policies governing surface water quality assessment, where the inclusion of helminth eggs and sediment monitoring will be critical.


2009 ◽  
Vol 6 (s1) ◽  
pp. S287-S303
Author(s):  
Waleed Manasreh ◽  
Atef S. Alzaydien ◽  
Malahmeh .M

Assessment of treated wastewater produced from Al-Lajoun collection tanks of the wastewater treatment plant in Karak province was carried out in term of physical properties, its major ionic composition, heavy metals and general organic content, for both wastewater influent and effluent. Sampling was done in two periods during (2005-2006) summer season and during winter season to detect the impact of climate on treated wastewater quality. Soil samples were collected from Al-Lajoun valley where the treated wastewater drained, to determine the heavy metal and total organic carbon concentrations at same time. The study showed that the treated wastewater was low in its heavy metals contents during both winter and summer seasons, which was attributed to high pH value enhancing their precipitations. Some of the major ions such as Cl-, Na+, HCO33-, Mg2+in addition to biological oxygen demand and chemical oxygen demand were higher than the recommended Jordanian guidelines for drained water in valleys. The treated wastewater contained some organic compounds of toxic type such as polycyclic aromatic hydrocarbons. Results showed that the soil was low in its heavy metal contents and total organic carbon with distance from the discharging pond, which attributed to the adsorption of heavy metals, total organic carbon and sedimentation of suspended particulates. From this study it was concluded that the treated wastewater must be used in situ for production of animal fodder and prohibit its contact with the surface and groundwater resources of the area specially Al-Mujeb dam where it is collected.


2021 ◽  
Vol 25 (2) ◽  
pp. 169-182
Author(s):  
Tony Venelinov ◽  
◽  
Galina Yotova ◽  
Veronika Mihaylova ◽  
Svetlana Lazarova ◽  
...  

Data analysis of wastewater samples at the outlets of wastewater treatment plants (WWTPs) of Pazardzhik, Plovdiv and Svilengrad, which discharge into the Maritsa River is presented. Total monthly loads for 2017 at the outlets are calculated using the monthly averages for the concentrations of chemical oxygen demand, biochemical oxygen demand, total phosphorus and total nitrogen (TN) and the monthly averages for the flow rates. The contributions of the WWTPs to the total river loads emphasize that the impact of WWTPs of Pazardzhik and Plovdiv is significantly greater than WWTP of Svilengrad. Additionally, river water samples were collected before and after the discharge points of the WWTPs in August 2018 and analyzed for water quality parameters listed in Directive 75/440/EEC. Comparison between the river concentrations before the outlet of WWPT - Pazardzhik and after the last sampling point (the outlet of WWTP - Svilengrad) indicates an increase for all the studied parameters, except for Al and Cu. Based on the results obtained for TN, the category of the surface water is significantly deteriorated after discharge of the WWTP - Plovdiv. Wastewater effect on the river surface water is also estimated by using a battery of ecotoxicological tests. The results are presented and compared by the classical approach using categorization based on water quality indicators.


Membranes ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 221
Author(s):  
Rafał Tytus Bray ◽  
Katarzyna Jankowska ◽  
Eliza Kulbat ◽  
Aneta Łuczkiewicz ◽  
Aleksandra Sokołowska

The paper presents the results of research on the use of ultrafiltration, using membranes of 200 and 400 kDa separation, for disinfection of municipal treated wastewater. The research was conducted on a fractional technical scale using real municipal treated wastewater from two large wastewater treatment plants treating most of the wastewater over the one-million polycentric Gdańsk agglomeration (1.2 million inhabitants). UF 200 kDa and UF 400 kDa processes enabled further improvement of the physical and chemical parameters of treated wastewater. Total phosphorus (to below 0.2 mg/L–UF 200 kDa, 0.13 mg/L–UF 400 kDa) and turbid substances (to below 0.2 mg/L, both membranes) were removed in the highest degree. COD was reduced efficiently (to below 25.6 mgO2/L–UF 200 kDa, 26.8 mgO2/L–UF 400 kDa), while total nitrogen was removed to a small extent (to 7.12 mg/L–UF 200 kDa and 5.7 mg/L–UF 400 kDa. Based on the reduction of indicator bacteria; fecal coliforms including E. coli (FC) and fecal enterococci (FE) it was found that the ultrafiltration is an effective method of disinfection. Not much indicator bacterial were observed in the permeate after processes (UF 200 kDa; FC—5 CFU/L; FE—1 CFU/L and UF 400 kDa; FC—70 CFU/L; FE—10 CFU/L. However, microscopic analysis of prokaryotic cells and virus particles showed their presence after the application of both membrane types; TCN 3.0 × 102 cells/mL–UF 200 kDa, 5.0 × 103 cells/mL–UF 400 kDa, VP 1.0 × 105/mL. The presence of potentially pathogenic, highly infectious virus particles means that ultrafiltration cannot be considered a sufficient disinfection method for treated wastewater diverted for reuse or discharged from high load wastewater treatment plants to recreational areas. For full microbiological safety it would be advisable to apply an additional disinfection method (e.g., ozonation).


2021 ◽  
Vol 3 (7) ◽  
Author(s):  
T. S. C. Quintão ◽  
F. G. Silva ◽  
A. L. Pereira ◽  
W. N. Araújo ◽  
P. M. Oliveira ◽  
...  

AbstractHuman enteric viruses, such as enteric adenoviruses (HAdV), are known to be involved with gastrointestinal disorders, especially acute gastroenteritis. Several studies have used HAdV as an indicator of water quality, since they are considered highly stable and widely distributed viruses in water matrices. The aim of this study was to detect and genotype HAdVs in water matrices impacted by discharges of treated effluents from wastewater treatment plants (WWTPs). Wastewater treatment plants from the sanitary system of the Brazilian Federal District were assessed in 2018 and 2019. Samples were collected upstream and downstream from discharge points for each WWTP. Viral concentration based on adsorption-elution and conventional PCR was used for molecular detection, and positive samples were sequenced for phylogenetic analysis. Pluviosity data for the period in which the samples were collected were obtained. Our results demonstrated the presence of HAdVs in 27.2% (61/224) of the samples. The positivity was significantly higher in downstream samples compared to upstream. Moreover, the HAdV positivity was higher in downstream samples collected from receiving water bodies impacted by secondary-level WWTPs in comparison with those impacted by tertiary-level WWTPs. Phylogenetic analysis demonstrated the presence of genotypes 40 and 41, with prevalence of HAdV genotype 41. Despite the predominance of HAdV-41, an increasing frequency of the HAdV-40 was associated with higher pluviosity. In conclusion, this study is the first documentation in the Brazilian Federal District dealing with the prevalence and diversity of HAdVs in several WWTP, along with their correlation with rainfall index.


2021 ◽  
Vol 11 (4) ◽  
pp. 1889 ◽  
Author(s):  
Agnieszka Micek ◽  
Krzysztof Jóźwiakowski ◽  
Michał Marzec ◽  
Agnieszka Listosz ◽  
Tadeusz Grabowski

The results of research on the efficiency and technological reliability of domestic wastewater purification in two household wastewater treatment plants (WWTPs) with activated sludge are presented in this paper. The studied facilities were located in the territory of the Roztocze National Park (Poland). The mean wastewater flow rate in the WWTPs was 1.0 and 1.6 m3/day. In 2017–2019, 20 series of analyses were done, and 40 wastewater samples were taken. On the basis of the received results, the efficiency of basic pollutant removal was determined. The technological reliability of the tested facilities was specified using the Weibull method. The average removal efficiencies for the biochemical oxygen demand in 5 days (BOD5) and chemical oxygen demand (COD) were 66–83% and 62–65%, respectively. Much lower effects were obtained for total suspended solids (TSS) and amounted to 17–48%, while the efficiency of total phosphorus (TP) and total nitrogen (TN) removal did not exceed 34%. The analyzed systems were characterized by the reliability of TSS, BOD5, and COD removal at the level of 76–96%. However, the reliability of TN and TP elimination was less than 5%. Thus, in the case of biogenic compounds, the analyzed systems did not guarantee that the quality of treated wastewater would meet the requirements of the Polish law during any period of operation. This disqualifies the discussed technological solution in terms of its wide application in protected areas and near lakes, where the requirements for nitrogen and phosphorus removal are high.


2021 ◽  
Author(s):  
Adamo R. Petosa ◽  
Monica Nowierski ◽  
Viviane Yargeau

Abstract Bioanalytical tools, namely in vitro bioassays, can be employed in tandem with chemical analyses to assess the efficacy of wastewater treatment and the potential for adverse effects from the discharges of wastewater into receiving waters. In the present study, samples of untreated wastewater (i.e. influent) and treated wastewater (i.e. effluent) were collected from two wastewater treatment plants and a wastewater treatment lagoon serving municipalities in southern Ontario, Canada. In addition, grab samples of surface water were collected downstream of the lagoon discharge. After solid phase extraction (SPE) using ion-exchange columns for basic/neutral and acidic compounds, respectively, the extracts were analyzed for a suite of 16 indicator compounds. The two SPE extracts were combined for analysis of biological responses in four in vitro cell-based bioassays. The concentrations of several indicator compounds, including the estrogens, 17β-estradiol and 17α-ethinylestradiol, were below the limits of detection. However, androstenedione and estrone were detected in several influent samples. The concentrations of these steroid hormones and some of the other indicator compounds declined during treatment but acesulfame K, carbamazepine, trimethoprim and DEET persisted in the effluent. The MTS- CellTiter 96® AQueous One Solution Cell Proliferation Assay (MTS) indicated that cell viability was not affected by exposure to the extracts. The Qiagen Nuclear Receptors 10-Pathway Reporter Array indicated that several cellular pathways were upregulated, with the greatest upregulation observed with the estrogen receptor (i.e. induction ratios 12 to 47) and the liver X receptor (i.e. induction ratios 10 to 45). The ERα CALUX assay indicated that estrogenic activity was lower in effluents compared to influents, with the greatest estrogenic activity observed for grab samples of influent from the lagoon (i.e. 56-215 ng L-1 17β-estradiol equivalents). Finally, the results of the Nrf2 Luciferase Luminescence Assay indicated a lower oxidative stress in the effluent samples. Overall, the present study demonstrates that chemical analyses are limited in their ability to predict or explain reductions in the toxicity of treated wastewater. There are thus advantages to using a combination of chemical analyses and in vitro bioassays to monitor the treatment efficiency of wastewater treatment plants and to predict the potential impacts of wastewater discharges into receiving waters.


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