Purification Plant Research Articles

Capillary electrophoresis and liquid chromatography for determining steroids in concentrates of purified water from Päijänne Lake

The research was done with partial filling micellar electrokinetic chromatography, microemulsion electrokinetic chromatography, and ultra-high performance liquid chromatography. The study focuses on determination of male and female steroids from cold and hot tap water of households in Helsinki City. The district´s raw water is made run from Päijänne Lake through a water tunnel to the purification plants in Helsinki area. The effluents delivered from the plants to households as tap water were sampled and used for the study. They were concentrated with solid phase extraction to exceed the detection limits of the three methods. With partial filling method the limits were 0.50, 0.48, 0.33, and 0.50 mg/L for androsterone, testosterone, progesterone, and testosterone-glucuronide, respectively. In microemulsion method the limit values were 1.33, 1.11, and 0.40 mg/L for androsterone, testosterone, and progesterone, respectively, and 0.83, 0.45, and 0.50 mg/L for hydrocortisone, 17-α-hydroxyprogesterone, and 17-α-methyltestosterone, respectively.In the tap water samples, progesterone concentrations represented the highest values being 0.22 and 1.18 ng/L in cold and hot water, respectively. They also contained testosterone (in all samples), its glucuronide metabolite (in 25% of the samples), and androstenedione (in 75% of the samples). The ultra-high liquid chromatographic method with mass spectrometric detection was used for identification of the steroids at µg/L level.

Purification of Cr(VI)-containing wastewater by chemical precipitation: test results of an experimental-industrial installation

We present the main results of experimental and industrial study of the developed process and pilot plant for purification of the Cr(VI)-containing rinse water by chemical precipitation. This technique implies full or partial return of treated water to rinse workpieces after chromium plating and prepare working solutions (precipitators). We characterize the manufacturing scheme of the pilot plant and the mode of its performance. Saturated aqueous solutions of Са(ОH)2 and Ва(ОH)2 were used as precipitating reagents. The tests confirmed the possibility of automatic dosing the reagents with due regard for the pH value of a medium, which can be used in both continuous and periodic rinsing. The operating conditions of rinsing the workpieces after electrochemical chromium plating were justified. We derived the equation for the calculation of the total salt content in the rinse water after its purification. We determined the duration of the rinsing without the need to renew the bath volume. The performed calculations substantiated the possibility of reducing the consumption of fresh water supplied for rinsing by the recycling of wastewater without deteriorating the quality of the rinsed workpieces. The reduction of water consumption by 35% was observed as compared with that stated by the regulations.

Evaluation of the most promising techniques overcoming the algal problems takes place during the purification of drinking water.

This work aims to study the technical problems of algal blooms that hinder the purification process of surface water used for drinking purposes and not its harmful effect on human health and the surrounding environment. It is also related to the demonstration of the improved coagulation process as an efficient technique in the algal removal from surface water by its application in jar tests. The study was carried out in the water purification plant in Nazlet Abdellah near the city of Assiut, Egypt. To achieve that, many ores and natural materials which aid in the removing of the algal blooms from surface water during the purification processes were tested. The examined materials should be technically and economically proper for improving the removal of algae from treated surface water for drinking purposes. The results showed that the kaolinite and bentonite (K and B) when coupled separately with aluminum sulfate (alum.) (the main coagulant agent) associated with the raw surface water in the flocculation basin were more efficient in the algae removal from treated surface water before reaching the sand filters by ratio up to 90%.

Pollutant Sources and Foaming Control Measures of Decarbonization Solution in Natural Gas Purification Plant

Yanbei project of Schlumberger Copower Oilfield Engineering Co., Ltd. - natural gas purification plant decarbonization unit is equipped with two sets of decarbonization systems (parallel operation). The two sets of systems adopt two tower process, full lean liquid circulation regeneration process, one tower absorption (absorption pressure 5.4mpag), one tower regeneration (regeneration temperature 95 oC~ 110 oC), purified natural gas carbon dioxide content <= 2.5vol%, single set The treatment capacity is 2300 KM3 / d. This paper introduces the problems existing in the decarbonization solution of the decarbonization unit in the natural gas purification plant in recent three years, analyzes the causes of pollutants affecting the quality of the decarbonization solution, and probes into the control measures for the pollution of the decarbonization solution, so as to provide reference.

정수지 추적자 모사를 위한 전산유체역학 해석

Flow characteristics have been studied with the tracer simulation for a N-clearwell using computational fluid dynamics(CFD) in this research. The flow is separated in the path of clearwell, showing the complicated turbulence physics. Thus, the behavior of tracer particles can be analyzed in the distribution, and especially the sampling location at the outlet can affect on the staying time of particles. The result of this study can be applied to the prediction for the performance of sanitization as well as evaluation and improvement for the water purification plants with the technology of CFD.

Feasibility of construction and installation site of differential pressure sensors for gas energy efficient plant for coarse and fine purification

The paper substantiates the construction and location of differential pressure sensors for a coarse and fine gas energy-saving plant. Energy saving is achieved by installing filtering cylindrical elements of fine and coarse purification one inside the other, optimizing their shape and substantiating the location of the differential pressure sensors. The results of the studies show that the total specific heat consumption for heating and ventilation of purification plants from all energy-saving measures for the proposed option is 1.85 times lower than the existing analogue of the non-optimized shape and measuring the pressure drop at the inlet and outlet branch pipes. The article also proved that the static gas pressure in the lower part of filter elements of the coarse and fine purification will always be higher than in their upper part. This results in a proportionally higher amount of inlet gas and therefore more solids settling in the bottom of the filter element. Measurement of the pressure drop in the lower part of the filter element, the most clogged with solid particles, makes it possible to receive a signal at the dispatching console earlier and provides a time reserve for technical personnel to timely remove accumulated blockages from coarse purification elements and prompt replacement of fine purification elements.

Unbaked materials from mixtures of waste sludge of a water purification plant, fly ash, and water glass

In water purification plants, a large area of urban land is using to store waste sludge (WS). The waste sludge from water filtration plants is aluminosilicate, which can be form a geopolymer. However, the waste sludge has low alkaline activity, so it must be used in combination with fly ash (FA) to create geopolymer products. Fly ash is a solid waste containing amorphous silica so that has high alkaline activity, suitable for treatment by geopolymer method. The geopolymerization of waste sludge from water purification plants is a relatively new method. The geopolymer is a binder formed by the chemical reaction between aluminosilicate materials and alkaline activated solutions. The alkaline activated solution used in these experiments was water glass (WG). The water glass is solution of sodium silicate (Na2O.nSiO2) dissolved in water. The research results of geopolymer materials from the mixture of fly ash, the waste sludge of Thu Duc water purification plant, Ho Chi Minh City (Vietnam), and water glass (WG) were introduced in this study. The activated Al2O3 and SiO2 oxides in the fly ash and the waste sludge can be dissolved in the water glass and polymerized into a geopolymer material. The test samples had pressed at a high pressure of 225 MPa to form cylindrical ones weighing approximately 3 grams, height about 18 mm, and 10 mm in diameter. These samples were then cured at 110 ◦C for 24 hours and at room temperature (30 +/- 5 ◦C). The methods of Fourier infrared spectroscopy (FTIR) and scanning electron microscope (SEM) had used to detect the microscopic structure and geopolymer bond formation of the samples. The compressive strength of the tested samples at 28 days old was higher than 3.5 MPa, the pH was less than 12.5, meeting the Vietnamese National Standards for unbaked materials (TCVN 6477:2016) and National Technical Regulation on environmental impact (QCVN 50:2013 / BTNMT), respectively. The results show a new approach of solidifying the waste sludge for further applications such as the manufacture of geopolymer concretes or landfill materials.

Pesticide Contamination in Drinking and Surface Water in the Cienega, Jalisco, Mexico

Sixty percent of global agricultural production depends on the use of pesticides, despite their adverse effects on human health and the ecosystem. In Mexico, the application of these products has been exacerbated, including pesticides already banned in other countries. The objective of this study was to determine pesticide concentrations in samples of water purification plants and surface water from the Cienega area of Jalisco, Mexico. A survey of 119 farmers with occupational exposure to pesticides was carried out in order to obtain information on the most frequently used pesticides. Subsequently, 51 samples taken at 7 different sites were analyzed using liquid chromatography and mass-mass spectrometry. The most frequently used pesticides were organophosphates (28.87%), pyrethroids (12.89%), and the herbicide paraquat (31.95%). In surface water, the prevalent pesticides were glyphosate (56.96–510.46 ppb) and malathion (311.76–863.49 ppb). Glyphosate levels were higher than the limits acceptable in daily water intake in Cumuato. Malathion levels exceeded the limits permissible by EPA in water purification plants in urban public establishments (100 ppb for children, and 200 ppb for adults). In addition, a multidimensional scaling analysis showed that the sampled sites could be grouped into 2 different bodies of water, based on similarities in their glyphosate concentrations (stress = 0.005), while the concentrations of malathion were heterogeneous (stress = 0.001).

Assessment of groundwater quality using geoelectrical potential and hydrogeochemical analysis in Eha-Amufu and environs, Enugu state, Nigeria

Presently, campaign for potable water supply is on the increase while the need to harness groundwater to alleviate the shortage of potable water is very crucial. This study investigated the groundwater potential of the local geologic formations and to determine the extent and distribution of the saline zones at Eha-Amufu. Integrated approach using geological, geoelectrical and hydrogeochemical investigations was adopted. Twenty-seven (27) vertical electrical sounding (VES) were performed at different locations within the area, using the Schlumberger electrode configuration with a maximum electrode separation of 600 m. Results from the VES revealed that the study area is made up of 3–6 geoelectrical layers, and are predominantly of QH and H curve types. The formations were observed to be characterized by low permeability zones/intervals, suggesting that Eha-Amufu could only possess perched aquifers table which supports the use of hand-dug wells. Hydro-chemical analysis of the ten (10) groundwater samples collected from different hand-dug wells indicated that the groundwater is characterized by Calcium (Ca)—Magnesium (Mg)—Chloride (Cl) water type, and could be classified as moderately hard to very hard. Water samples showed evidence of contamination with heavy metal such as Pb2+ beyond WHO standard, thereby making it unfit for domestic uses and consumption. Further result probe revealed that the local geology is the major process controlling the fate of groundwater chemistry in the area through weathering and rock–water interaction. Therefore, the present study proposes that other forms of portable water provisions should be explored such as harvesting and treatment of the various river resources in the area using purification plants and development of regional water conduits.

The adsorption efficiency of nitrogen and phosphorus by in-situ remediation of modified sediment composite material.

Dredged sediment can occupy a large amount of land area, resulting in waste of land resources, and high disposal costs. In response to the problem, this work calcinates and modified the sediment and compounds it with the modified water purification plant sludge, zeolite powder, and bentonite. This is used as a covering material to inhibit the release of nitrogen (N) and phosphorus (P) in the sediment. The results showed that sediment modified composite material covering effectively reduces the release of nitrogen (N) and phosphorus (P) in the sediment, especially the release of P. When the thickness of the covering layer is 3 cm, the reduction rate of total N, NH4+-N, and total P in the overlying water by the modified composite material of sediment is 61.58, 79.59, and 70.34%, respectively. It can be seen that the covering material has a significant effect on the control of the release of N and P in the sediment. Additionally, the reduction of nutrients in the overlying water can overcome the negative effects of temperature rise in controlling the release of N and P in the sediment.

Comparing the Effects of Ventilation and Air Purification Plants on Radon Concentration in the Lower and Upper Floors of a Building

Comparing the Effects of Ventilation and Air Purification Plants on Radon Concentration in the Lower and Upper Floors of a Building

Effectiveness of household water purifiers in removing perfluoroalkyl substances from drinking water.

Drinking water is one of the major exposure routes to Perfluoroalkyl substances (PFASs). These chemicals are scarcely removed by the conventional process in water purification plants. In the present study, four models of pitcher-type water purifiers (A-D) were tested to evaluate their removal effect on six PFASs including PFOS and PFOA. All of the water purifiers removed PFASs, but the efficiency was dependent on the models. Model C was most effective; more than 90% of all PFASs were removed through the recommended life of the filter cartridge. Model D was least effective; its removal efficiency declined below 50% by the end of the cartridge's life. When compared by the carbon chain length of PFASs, the removal efficiency was "C12 > C10 > C8 > C6" in all models. This study clearly demonstrates that household water purifiers are effective in decreasing the exposure to PFASs through drinking water.

Deliberative architecture for smart sensors in the filtering operation of a water purification plant

The increase of applications for industrial smart sensors is booming, mainly due to the use of distributed automation architectures, industrial evolution and recent technological advances, which guide the industry to a greater degree of automation, integration and globalization. In this research work, an architecture for deliberative-type intelligent industrial sensors is proposed, based on the BDI (Belief Desire Intentions) model, adaptable to the measurement of different variables of the filtering process of a water purification plant. An intelligent sensor with functions of signal digitalization, self-calibration, alarm generation, communication with PLC, user interface for parameter adjustment, and analysis with data extrapolation have been arranged. For decision making, the use of fuzzy logic techniques has been considered, which allows imprecise parameters to be appropriately represented, simplifying decision problem solving in the industrial environment, generating stable and fast systems with low processing requirements. The proposed architecture has been modelled, simulated and validated using UML language in conjunction with Petri nets, which facilitate the representation of discrete system events, presenting them clearly and precisely. In the implementation and testing of the prototype, C/C ++ language has been used in an 8-bit microcontroller, experimentally corroborating the operation of the device, which allowed evaluating the behavior of a pseudo-intelligent agent based on the requirements of the water treatment plant, and also through comparisons with similar works developed by other researchers.

Simulation of Illipe Butter Purification Originated from West Kalimantan by SuperPro Designer

Tengkawang is one of the commodities of non-timber forest products which has been a life of support for people around the forest. Seeds produced by Tengkawang trees are one of the export commodities. However, unfortunately, the process of exporting Tengkawang seeds abroad often requires a long time to reduce the quality of the Tengkawang seeds. Processing of Tengkawang seeds into oil is a solution to the decline in quality of Tengkawang seeds. Like standard crude vegetable oil, Tengkawang oil also contains impurities. Therefore, a purification process to remove these impurities is needed. This research was conducted to produce purified Tengkawang fat optimally. Purification stages include degumming, neutralization and bleaching. This research will focus on the simulation of purified Tengkawang fat production. In this case, the simulation is carried out as an estimator of the feasibility value roughly whether a fat purification plant can be realized or not.

Study of the possibilities of integrated treatment of flue gases and waste water from coal-fired heat power plants

The results of laboratory studies carried out to identify the possibility and effectiveness of technologies for the complex recycling of components of flue gases and wastewater from thermal power plants and industrial boilers are presented. The following factors were investigated: the degree of saturation of water solutions with CO2, the efficiency of using these solutions for the regeneration of cation exchangers, the properties of regeneration solutions intended for the regeneration of cation exchange filters prepared using components of flue gases obtained from the combustion of organic fuel in the laboratory by saturating water of various compositions, the degree of saturation of condensate and waste-water with components of flue gases, as well as the degree of regeneration of cation exchangers with such regeneration solutions. After research in the laboratory, a laboratory installation was created in an industrial environment to determine the properties of solutions obtained from wastewater and flue gases obtained after production processes at a power plant. The technologies were developed for the complex recycling of flue gases and waste-water from thermal power plants with the production of CO2 with a purity of 99.9%, technical nitrogen with a purity of 95%, special solutions for the regeneration of cation exchangers in water purification plants of industrial enterprises. The results obtained make it possible to minimize the volume of emissions into the atmosphere and the volume of waste-water from thermal power plants.

Анализ современных методов переработки кубовых остатков атомных электрических станций

To date, more than 600 thousand m3 of liquid radioactive waste has been accumulated at Russian nuclear power plants (NPPs). In addition to radioactive components, they contain a large amount of mineral salts, organic matter, oil products, and suspensions. The problem of overfilling the storage facilities for liquid waste at some NPPs is critical and has to be solved urgently. The article presents modern methods for processing vat residues and the existing prerequisites for modernizing ion-selective purification plants, which are based on the results of research works carried out by various teams. A technological analysis of the methods for evaporation and ion-selective purification of vat residues with identified shortcomings of individual stages of the technologies is carried out. Decontamination of secondary products of liquid radioactive waste processing implies the possibility of subsequently separating valuable components for reusing them. Their decontamination is necessary, since these wastes are essentially high-salt solutions with a specific activity of 106-107 Bq/l contaminated with fission products, radionuclides of corrosion origin, and various substances used to decontaminate the equipment and maintain the water chemistry. It is proposed to apply the electrodialysis method for separating a multicomponent solution of the decontaminated NPP vat residue and to use the obtained products at the plant. Owing to the partial extraction of valuable components from decontaminated vat residues, it becomes possible to reduce the amount of waste and return the separated substances into the main process cycle, thereby reducing the expenditures for initial reagents. To implement the developed technology for component-wise separation of the initial solution, a laboratory electrodialysis facility was manufactured. The project implementation feature was that in dealing with boric acid salts, it is necessary to take into account the danger of their precipitation at certain pH values. It was found that to minimize the escape of boric components, the process should be conducted at low pH values, i.e., the solution should be acidified with the nitric acid obtained in the process. The obtained study results can be used to modernize the cementation plants.

ДОСЛІДЖЕННЯ ТВЕРДИХ ЗАВИСЛИХ РЕЧОВИН У ВОДАХ, ЩО НАДХОДЯТЬ НА ГАСІННЯ КОКСУ

The article is devoted to the results of work for the study of the composition and quantitative content of suspended solids (SS) in the wastewater of coke plants before and after biochemical purification plants (BPP), as well as in other waters involved in the process of coke extinction. The characteristic indicators have been investigated of waters before and after BPP of five coke-chemical enterprises of Ukraine, as well as the chemical composition of suspended solids in water after BPP, etc. It is shown that SS in water after BPP is represented mainly by activated sludge, which is partially oxidized to CO2 when water is supplied to hot coke. The rest activated sludge is returned with water condensate to the settling tank of the extinction tower and, thus, is not emitted into the atmosphere in the form of SS. In addition to sludge, the particles of coke, coal and products of the equipment corrosion are present in the purified water after the BPP and in the water of the extinction tower settling tank. The possibility of the presence of concrete particles is also not excluded. To establish the nature of solid particles, their elemental composition and ash composition has been determined. In particular, it was found that the ash composition of suspended solids from water after BPP quantitatively differs from the both of ash composition of coal concentrates and the composition of concrete. For example, the mass fraction of silicon dioxide in the suspended solids of water after BTH is much lower than in concrete and in ash of coal concentrates. The detected predominance of iron (III) oxide in the composition of SS ash after BPP is explained by the presence in the selected samples of products of the equipment corrosion. Based on our research, it is proposed to make changes in the normative document "Technological standards of permissible emissions of pollutants from coke ovens", namely in chapter IV "Operating conditions of coke ovens" par. 8: to exclude such a normative value as the content of suspended solids in water after BPP, which is submitted for coke extinction. Keywords: water for coke extinction, water after biochemical purification, suspended solids (SS), content, chemical composition, elemental composition, ash composition. Corresponding author A.L. Borisenko, e-mail: zd@ukhin.org.ua

Strengthening of the reinforced concrete tank of anaerobic purification plants with the manufacture of biogas, damaged as a result of design and construction errors

The defects and damages of bearing structures (walls, covering) of the solid-cast reinforced concrete tank were identified and detected using visual and instrumental testing. The actual reinforcement of the tank was determined and coordinated with designed reinforcement. Furthermore, the deformations were measured, the cracks opening in the walls and its depth in the concrete were detected and was also the strength quality of concrete was defined. During the year of the operation, the tank developed a considerable system of cracks in all lateral walls from technological loadings. At the same time, the width of the crack opening exceeded the limit values for reinforced capacitive structures (wk), which is equal to 0.1 mm. The walls lost tightness, the use of the structure in the technological process was suspended. Checking calculations of the design solutions was carried out for the elements of the tank on technological loadings in the software package LIRA to find the causes of the cracks opening and water penetration in the walls of the reinforced concrete tank. It was determined that the existing design solutions did not ensure the bearing capacity and the fracture strength of bearing reinforced elements of the tank and its spatial rigidity from technological loadings. Necessary reinforcement was defined by ensuring the strength and possible limitation of the width of the cracks opening. This article presents the technical solutions concerning the strengthening of repair bearing elements of reinforced concrete spatial frame of the existing structure. The external bandages (reinforcing steel 4d32A400C) and inner tension bars (stainless steel round pipes 168 x 5 mm) were used as the strengthening of the reinforced concrete tank.

Опыт внедрения систем ионоселективной очистки трапных вод от радионуклидов на блоках 1-2 НВАС-2

The article is dedicated to the assessment of the experience in drainage water purification from radionuclides using ion-selective purification method on Units 1,2 Novovoronezh-2 NPP. Application of an ion-selective sorbent based on nickel ferrocyanide, as well as the preliminary oxidation of corrosive origin radiongjuclides, allow to achieve a satisfactory quality of purification from Cs-134, Cs-137, Co-60, Co 58, Mn-54, Cr-51. However, this method turned out to be ineffective for drainage water purification from Be-7, Sb-124, Sb-125. The article presents a possible method for drainage water purification from Be-7, Sb-124, Sb-125 using an iron-based coagulant, prospects for the modernization of the ion-selective drainage water purification plant, as well as plans to improve methods for drainage water purification at Novovoronezh-2 NPP

Inactivation of Hepatovirus A in wastewater by 254 nm ultraviolet-C irradiation

Hepatovirus A is known as a waterborne and foodborne virus that can be transmitted from one person to another through contaminated water and raw food. Therefore, it is necessary to survey the circulation of this type of enteric virus in the wastewater to prevent prospective outbreaks. Wastewater samples collected from WWTP El Menzeh I and Charguia I have been the subject for physicochemical, bacteriological (MPN) and virological analyses. Hepatovirus A (HAV) detection was carried out using the standard reverse transcription-polymerase chain reaction (RT-PCR). Hepatovirus A was detected respectively in 62% (63/102) and 66% (92/140) of the collected wastewater samples at El Menzeh I and Charguia I WWTPs. The treated effluent by natural oxidizing lagoon procedure was characterized by a poor physical-chemical and virological qualities but with excellent bacteriological quality. Consequently, this effluent is not suitable to be recycled and reused in agriculture or even dismissed in the environment. The treated sewage by activated sludge and rotating biodisk procedures turned out to be of a very good physical-chemical quality but with a poor bacteriological and virological quality. After tertiary UV-C254 nm irradiation, the faecal indicator bacteria concentration was mostly reduced and removed. These findings confirmed the need for improvement and upgrade of the treatment processes used in these two studied sewage purification plants and the necessity of implementation and establishment of a proper national virological standard to control the circulation rates of enteric viruses in Tunisian municipal wastewater.