Wastewater Treatment Station Research Articles

Using locally isolated Chlorella vulgaris in Wastewater Treatment

In this study locally isolated microalgae (Chlorella vulgaris Bejerinck) was used in wastewater treatment to reduce the pollutant parameters. Three parameters were studied to determine the efficiency of Chlorella vulgaris in reducing COD, BOD and PO4 concentration. Samples of wastewater were taken from a primary station in Al-Rustomiya wastewater treatment station. Three different dilutions of wastewater were tested; 100% waste, 75%waste 25%waste with distilled water. Chemical oxygen demand (COD) values started with 370mg/l, 270mg/l and 200mg/l for samples A, B and C respectively, and it reached after 14 days to 112 mg/l, 88 mg/l, and 120 mg/l. Biochemical oxygen demand (BOD) started with 241mg/l, 200mg/l, and 170 mg/l for samples A, B and C respectively, and it declined to 110 mg/l, 61 mg/l, and 112 mg/l. Finally PO4 started with 39.9 mg/l, 30 mg/l, 21 mg/l and it reached to 17.1mg/l, 8mg/l, 11.2mg/l for samples A, B and C respectively. Sample B showed the best removal values for COD, BOD and PO4 which reached to 88 mg/l, 61 mg/l, and 8 mg/l respectively.

A new natural method for sludge drying of wastewater treatment station—The case of Algeria

This paper presents an experimental application aiming at reducing the sludge drying time in the STEP drying beds of domestic wastewater. This method works with the mixtures of sludge from the Souk Ahras city STEP at different percentages, and with natural material wastes such as scrap limestone flour (SLF) and/or refractory bricks flour based on magnesia (RBFM) from Hadjar Essoud (north eastern Algeria) cement furnaces. The applied experiment focused on mixtures testing for “mud-flour” varying between 12.5 and 100%. The achieved results for mixtures of 25% SLF and RBFM can be noted as: for the mud blindness from 0 to 20%, in the dry season (August, average temperature 34°C), a globally estimated drying time of 1.5 d; for the mud blindness from 0 to 30% in the wet season (December, average temperature 16°C), a substantial drying time in the range between 4 and 5 d. In a mixture of 25%, the sludge has been reduced to more than 95% of their initial weight (a reduction from 400 to 17 g). The results show two strong desirable aims of STEP sludge management; on the one hand the drying time reduction and its corollary of drying areas and deposit, and on the other hand the recycling of the waste limestone of cement plants.

Removal of potentially toxic elements in domestic wastewater treatment stations by wetlands

Lack of sewage treatment is amongst the main sanitation problems of Brazil, mainly in low income rural communities. Seeking alternative and low cost technologies to treat such effluents is mandatory. This study aimed to verify the efficacy of a sewage treatment system by root zone stations (constructed wetlands) to remove potentially toxic elements (Cu and Zn) in two wastewater treatment stations (WWTS) (school and single family residence) of small communities in the city of Irati (PR). Three campaigns were carried out between May and September 2011, with two samples each (inlet and outlet), all in replicate, and quantified through atomic absorption spectrometry with flame atomization (AAS-flame). The presence of NH3 in the effluent favored the reduction of pH values, which remained within the neutrality and alkalinity range (from 8.0 to 9.1 for the school effluent and from 6.9 to 7.8 for the single family residence). For this pH range, it was possible to obtain Cu (25% to 75%) and Zn (0 to 100%) precipitation. In general, the constructed wetlands systems were efficient to remove Cu and Zn (between 25% to 75% regarding Cu; and between 67% to 100% regarding Zn), revealing advantages of its use in small communities.

Removal of Phenol Using Spore Forming <i>Bacillus</i> ABO11 Isolated from Waste Water Treatment Plant

Twenty isolates of bacteria were isolated from contaminated wastewater collected from wastewater treatment station, used to clean the raw sewage at Jeddah on minimal medium containing phenol (0.5 g/l) as carbon source while at 0.6 g/l phenol, five isolates belonging to Gram positive and Gram negative bacteria were obtained after 10 days of growth at 37°C. All the tested bacteria were tested for phenol degradation in liquid medium and isolate ABO11 was the most active isolate in phenol degradation. It was selected and tested for the ability to use phenol as carbon and energy source. It was identified as Bacillus sterothermophilus ABO11 using morphological and biochemical tests. Genetic studies confirmed the identification. Bacterial growth and phenol degradation by the selected bacterium were determined using different initial phenol concentrations (0 - 1.0 g/l). Very weak growth was recorded at 0.8 g/l and no growth or degradation was observed at higher phenol concentration. The isolate was adapted to grow in presence of 0.8 g/l phenol and phenol degradation was checked up to 12 days of growth. Percentage of degradation was 100% after 10 days. Maximum growth was observed at 40°C, pH 8 and using NH4Cl as nitrogen source. In conclusion, the selected isolate, Bacillus sterothermophilus ABO11 can be used in protecting the environment from phenol pollution.

The Influence of Sugar-Processing Effects on Water in Treatment Plants

The present paper is a study regarding the influence of waters resulted from the production of sugar from sugar beet on waters in wastewater treatment plants. The objective of the paper is to prove that wastes, especially organic ones, resulted from the production of sugar from sugar beet (Beta vulgaris L.) may have a significant effect on the quality of water entering or leaving water treatment plants, unless appropriate measures are taken to pre-treat and/or treat wastewater. That is why the existence of norms, standards and/or instructions establishing the qualitative conditions of water, on different lines or technological flows, is particularly important for the policies regarding the economical use of water resources. The fact that the capacity of the wastewater treatment station in Ludus is below the designed level, the sometimes inadequate separation of vegetable wastes from sugar beet root before processing lead to the exceedance of the accepted value for some water quality indices (total suspensions, CCOCr), especially during the campaign periods.

The color removal and fate of organic pollutants in a pilot-scale MBR-NF combined process treating textile wastewater with high water recovery.

A combination of membrane bioreactor (MBR) and nanofiltration (NF) was tested at pilot-scale treating textile wastewater from the wastewater treatment station of a textile mill in Wuqing District of Tianjin (China). The MBR-NF process showed a much better treatment efficiency on the removal of the chemical oxygen demand, total organic carbon, color and turbidity in comparison with the conventional processes. The water recovery rate was enhanced to over 90% through the recycling of NF concentrate to the MBR, while the MBR-NF showed a stable permeate water quality that met with standards and could be directly discharged or further reused. The recycled NF concentrate caused an accumulation of refractory compounds in the MBR, which significantly influenced the treatment efficiency of the MBR. However, the sludge characteristics showed that the activated sludge activity was not obviously inhibited. The results of fluorescence spectra and molecular weight distribution indicated that those recalcitrant pollutants were mostly protein-like substances and a small amount of humic acid-like substances (650-6,000 Da), which contributed to membrane fouling of NF. Although the penetrated protein-like substances caused the residual color in NF permeate, the MBR-NF process was suitable for the advanced treatment and reclamation of textile wastewater under high water yield.

Using ozonation-hydrolysis acidification to the pharmaceutical tail wastewater pretreatment

In order to solve the problems of poor biodegradability and high concentrations of non-biodegradable substances from pharmaceutical wastewater after preliminary treatment, the organic components of the tail water (effluent from the preliminary treatment devises of the pharmaceutical industry wastewater treatment station) were analyzed and the method of ozonation-hydrolysis acidification was used to treat tail water from the pharmaceutical factory. The ozone dosage, the reaction time and the changes of biodegradability were studied. The results measured by GC-MS showed that there were 51 types of organic substances in tail water which reduce the biodegradability. The results of the tests showed that 30 mg/L of ozone and 60-minutes of oxidation time were suitable conditions. In the ozonation–hydrolysis acidification process the COD removal rate ranged from 20% to 50%. The test results showed that the ozonation-hydrolysis acidification method could effectively improve the biodegradability of wastewater and provide the foundation for the follow treatment in urban sewage treatment plant using biological methods.

Treatment of sludge produced from AL-Dubaiee Station using Drying beds

The present drying beds of Al-dubaiee waste water treatment station is not enough, thus, the present study is performed. In this work, many experiments have been made in order to find out the optimum thickness of the drying bed and to find suitable filtration agents from local materials. Moreover the effect of flocculent agents is tested. The results show that optimum thickness is 30 cm of brick and 25 cm of sand. Ferric concentration of 100 mg/l gives the best results. It is also found that drying efficiency is improved with reducing specific filtration resistance. The effluent waste water is found suitable for agriculture purpose concerned heavy metal concentration. special drying bed (handy slop towards center) is constructed and it is found that the required area is reduced by 50%.

Site-related and seasonal variation of bioaerosol emission in an indoor wastewater treatment station: level, characteristics of particle size, and microbial structure

The emission of the airborne bacteria and fungi from an indoor wastewater treatment station adopting an integrated oxidation ditch with a vertical circle was investigated. Microbial samples were collected by the six-stage viable Andersen cascade impactor, and the samples were collected in triplicate in each sampling site per season. Culture-based method was applied to determine the concentrations of the airborne bacteria and fungi, while the cloning/sequencing method was used to characterize the genetic structure and community diversity of airborne bacteria. The highest concentrations of airborne bacteria (4155 ± 550 CFU/m3) and fungi (883 ± 150 CFU/m3) were obtained in June (summer). The lowest concentration of bacteria (1458 ± 434 CFU/m3) was determined in January (winter), and the lowest concentration of fungi (169 ± 40 CFU/m3) was found in March (spring), respectively. The particle size distribution analysis showed that most culturable bacteria obtained in all the sampling sites were in the particle size range of 1.1–4.7 µm. Most culturable fungi had particle sizes in the range 1.1–3.3 µm. Microbial population analysis showed that Bacillus sp., Acinetobacter sp., and Lysinibacillus were the main groups obtained in S1. Enterobacter was the dominant group in sampling site S2. Both the concentrations and particle size distribution of the bioaerosols in the enclosed space presented a seasonal and site-related variation. Concentration and richness of microorganisms in bioaerosols in June were higher than in September and January. The particle size distribution varied between the sampling sites, and proportion of large particles was higher in S2 than in S1 because of the settlement of large particles. Pathogenic species, such as Acinetobacter lwoffii, Staphylococcus saprophyticus, and Enterobacter sp., were isolated from the bioaerosols, which could pose serious latent danger to sewage workers’ health.

Technology Development on Heavy Metal-Contained Sludge Reduction and Resource Recovery on Stainless Steel Cold-Rolled Mixed Sludge

Based on characteristics of stainless steel cold-rolled products pickling wastewater, a new process route with advantages of sludge originally reduction, wastewater two-stage treatment, Heavy metal-contained sludge and calcium-salt sludge separately recovery is developed. As 2 waste-water treatment stations operation results have shown, during the passed 6 years, annual sludge reduction ratios (per tons product) reach 43.64% and 50.29% respectively, realizing 105.6 thousands tons of sludge reduction effect and 68.04 millions CNY economic benefits. After two-stage process treatment, effluent water can reach emission standards steadily, Fe,Cr and Ni total contents in the front-part heavy-metal sludge increase from 10% to 30~40% compared with that of one-stage wastewater traditional treatment process, with dramatically decrease of F and S impurities content, therefore it can be used as ferric-contained sludge; while among the post-part calcium-salt sludge, F and S recovery ratios reach 20~40%, with Fe,Cr and Ni total content falls below 3%, therefore it can be used as fluorgypsum or fluorite. Since this technology fit the trend of hazardous waste original reduction and resource categorized recycle, it has a broad application prospect in stainless steel enterprise.

Stochastic enumerative algorithm optimization construction scheme of wastewater treatment station

Stochastic enumerative algorithm optimization construction scheme of wastewater treatment station

Treatment of sludge produced from AL-Dubaiee Station using Drying beds

The present drying beds of Al-Dubaiee waste water treatment station is not enough, thus, the present study is performed. In this work, many experiments have been made in order to find out the optimum thickness of the drying bed and to find suitable filtration agents from local materials. Moreover the effect of flocculent agents is tested. The results show that optimum thickness is 30 cm of brick and 25 cm of sand. Ferric concentration of 100 mg/l gives the best results. It is also found that drying efficiency is improved with reducing specific filtration resistance. The effluent waste water is found suitable for agriculture purpose concerned heavy metal concentration. Special drying bed (handy slop towards center) is constructed and it is found that the required area is reduced by 50%.

Research Methods Adopted for Evaluation of the Condition of the Building Materials Used in Construction of the Masonry Structures on the Site of the Auschwitz-Birkenau State Museum in Oświęcim

The article shows the extent of work carried out within the framework of the project Research on the development of methods of maintenance, security and strengthening the structure of objects, elements of their finish and substrate, taking into account the statics and physics of the buildings within the Auschwitz-Birkenau State Museum in Oswiecim, as part of the multi-annual program of comprehensive, systematic preservation activities aimed at preserving the Auschwitz-Birkenau Memorial. The project is funded by the Auschwitz-Birkenau Foundation.The aim of the project was to create a base of information on the actual condition of the existing facilities and, on that basis, to develop preservation methods and ways to prevent their further destruction while maintaining their current character.The article presents the results of the research into the condition of the structural materials done – as an example – on one of the elements of the camp technical infrastructure – the wastewater treatment station. It also describes how the research itself was done. The scope included finding out the compressive strength of the masonry, bricks and mortar as well as determining the content of sulphate, chloride and nitrate salts both in the bricks and mortar. The article discusses the results of macroscopic and microscopic observations done on bricks and mortar using scanning microscopy.

Adequate Advance Provided by a Familiar Fluid Dynamic Balance Principle to Tools and Techniques for Water Quality Interpretation: Experienced in Yaoundé (Cameroun) 2<sup>nd</sup> Supply Dam

In a fluid (liquid or gas) at rest, the isobars are horizontal surface. This fluid dynamic balance theorem provides adequate advance to tools and techniques for Water Quality Interpretation. We deal in this paper, with an effective way of exploiting the familiar communicating containers’ principle. That formally consists on providing water samples from desired depths of rivers, oceans, retention dams, etc. The prevailing limiting factor to achieve this feat is the length of our sampling pipes named Mbane Bathymetric Tube (MBT) designed for this purpose when rivers or retention dams are very deep. Providing drinking water to urban growing populations is a challenge that no government can escape. Therefore, improving the tools and techniques for water quality interpretation is an adequate advance for drinking water managerial techniques because this allows the recovery of contaminated water which abounds on the earth by acquiring appropriate wastewater treatment stations. The aim of the manuscript is to provide a brief theoretical description of our designed sampling equipment to allow everyone who is going to use it to solve in advance problems brought by Archimedes’ pressure force when experiencing the sampling pipes. Archimedes’ pressure force acts mainly when moving the sampling pipes to water lower levels and then opening its protective cover which allows the communication with the supply dam.

Reuse of refinery's tertiary-treated wastewater in cooling towers: microbiological monitoring.

The study was planned to quantify the distribution of bacteria between bulk water and biofilm formed on different materials in an industrial scale cooling tower system of an oil refinery operating with clarified and chlorinated freshwater (CCW) or chlorinated tertiary effluent (TRW) as makeup water. The sessile and planktonic heterotrophic bacteria and Pseudomonas aeruginosa densities were significantly higher in the cooling tower supplied with clarified and chlorinated freshwater (CTCW) (p < 0.05). In the two towers, the biofilm density was higher on the surface of glass slides and stainless steel coupons than on the surface of carbon steel coupons. The average corrosion rates of carbon steel coupons (0.4-0.8 millimeters per year (mpy)) and densities of sessile (12-1.47 × 10(3) colony-forming unit (CFU) cm(-1)) and planktonic (0-2.36 × 10(3) CFU mL(-1)) microbiota remained below of the maximum values of reference used by water treatment companies as indicative of efficient microbial control. These data indicate that the strategies of the water treatment station (WTS) (free chlorine) and industrial wastewater treatment station (IWTS) followed by reverse electrodialysis system (RES) (free chlorine plus chloramine) were effective for the microbiological control of the two makeup water sources.

Relationship of Biometric Size - Weight , Nutritive Value and Metal Concentrations in Clarias Lazera ( Cuvier and Valenciennes ) Reared in Treated Wastewater

The objective of the present study was to investigate the nutritive value and heavy metals accumulation in the flesh of Clarias lazera (Cuvier and Valenciennes) reared in the discharge canal of Soba wastewater treatment station, south Khartoum, Sudan. A total of 57 fish were collected from the canal and 52 from the White Nile which served as the control. The proximate composition of fish and concentrations of eight hazardous heavy metals i.e. chromium (Cr), iron (Fe), copper (Cu), zinc (Zn), lead (Pb), robidium (Rb), strontium (Sr), and mercury (Hg) in the flesh of C. lazera were measured. The results which were statistically analyzed revealed insignificant differences in moisture, ash, fat contents, energy value, and fat: protein ratio (P>0.05) between the two studied sites. A significant difference (P 0.05). Fe, Cu, Zn and Rb concentrations were significantly higher in treated wastewater fishes than natural water fishes (P 0.05). Nevertheless, the concentrations of most considered elements were lower than levels recommended by various international agencies.

Treatment of industrial waste pharmochemical by fenton’s reagent

This study aims to determine the optimal concentration of Fenton reagent for pharmaceutical chemistry industry, varying the concentration of ferrous sulfate and hydrogen peroxide subsequently monitor the treatment in pilot scale and wastewater treatment (WWTP) station of the main parameters: color, odor, pH and COD. Pilot tests to obtain the guidelines used in formulating the Fenton reagent to be used in large scale in the effluent tank were performed, the pilot test of experiment T12 showed the best result (Color and COD) for the composition of the treatment with: 3.2 mL of H2O2 and 160 mg Ferrous Sulfate. From this parameter the treatment was carried out daily monitoring in the laboratory and pilot scale, and the values were similar for both treatments, with the percentage reduction of COD of 93.57% in the lab test and 94.00% in the ETE test. The process of wastewater treatment using Fenton reagent showed excellent results, with better values than the limits established by law. But the treatment time of 16 days is not feasible for some industries, but is smoothly carried out in the study industry.

Reduction and characterization of bioaerosols in a wastewater treatment station via ventilation

Bioaerosols from wastewater treatment processes are a significant subgroup of atmospheric aerosols. In the present study, airborne microorganisms generated from a wastewater treatment station (WWTS) that uses an oxidation ditch process were diminished by ventilation. Conventional sampling and detection methods combined with cloning/sequencing techniques were applied to determine the groups, concentrations, size distributions, and species diversity of airborne microorganisms before and after ventilation. There were 3021±537CFU/m3 of airborne bacteria and 926±132CFU/m3 of airborne fungi present in the WWTS bioaerosol. Results showed that the ventilation reduced airborne microorganisms significantly compared to the air in the WWTS. Over 60% of airborne bacteria and airborne fungi could be reduced after 4hr of air exchange. The highest removal (92.1% for airborne bacteria and 89.1% for fungi) was achieved for 0.65–1.1μm sized particles. The bioaerosol particles over 4.7μm were also reduced effectively. Large particles tended to be lost by gravitational settling and small particles were generally carried away, which led to the relatively easy reduction of bioaerosol particles 0.65–1.1μm and over 4.7μm in size. An obvious variation occurred in the structure of the bacterial communities when ventilation was applied to control the airborne microorganisms in enclosed spaces.

Verifying the efficacy in removing nutrients using wastewater treatment stations by constructed wetlands

Due to the difficult access to conventional systems of collection and sewage treatment in low income rural communities, there is the need for low cost alternative technologies to treat such effluents. This study aimed to verify the efficacy of sewage treatment systems by constructed wetlands in the removal of the nutrients: nitrogen (N), phosphorus (P), calcium (Ca) and Magnesium (Mg), in two wastewater treatment stations (WWTS) located in a school and in a family house in small communities in the city of Irati/Brazil. Results revealed a good performance in the removal of the nutrients N and P in both systems, 75% and 37% for the house and 41% and 69% for the school, respective; which is associated to the plant uptake ability. However, the index of Ca and Mg presented significant increase, with 156% and 88% for the house and 165% and 128% for the school effluent, respectively, due to the use of gravel (rich in Ca and Mg) in the filter composition.

Evaluation of Two Biosorbents in the Removal of Metal Ions in Aqueous Using a Pilot Scale Fixed-bed System

The aim of the present work was to investigate the adsorption of toxic metal ions copper, nickel and zinc from aqueous solutions using low cost natural biomass (sugar cane bagasse and green coconut fiber) in pilot scale fixed-bed system. The Hydraulic retention time (HRT) was 229 minutes and the lowest adsorbent usage rate (AUR) found was 0.10 g.L -1 for copper using green coconut fibers. The highest values of adsorption capacities founded were 1.417 and 2.772 mg.g -1 of Cu(II) ions for sugarcane bagasse and green coconut fibers, respectively. The results showed that both sugarcane bagasse and green coconut fiber presented potential in the removal of metal ions copper, nickel and zinc ions from aqueous solution and the possible use in wastewater treatment station.