Sewage Cleaning Research Articles

Hydrodynamics of pitching hydrofoil in a plane Poiseuille flow

Several advanced medical and engineering tasks, such as microsurgery, drug delivery through arteries, pipe inspection, and sewage cleaning, can be more efficiently handled using micro- and nano-robots. Pressure-driven flows are commonly encountered in these practical scenarios. In our current research, we delve into the hydrodynamics of pitching hydrofoils within narrow channels, which may find their potential applications in designing bio-inspired robots capable of navigating through pressure-driven flows in confined channels. In this paper, we have conducted a numerical investigation into the flow characteristics of a National Advisory Committee for Aeronautics (NACA) 0012 hydrofoil pitching around its leading edge within a plane Poiseuille flow using a graphical processing unit accelerated sharp interface immersed boundary method solver. Our study considers variations of the wall clearance from 20% to 50% of the channel width. We have explored the hydrodynamic features such as instantaneous and time-averaged values of lift, drag, input power, and torque for different wall clearance ratios and oscillation frequencies in the range of Reynolds number 100–200 based on the mean velocity and channel width. We have tried to explain the force, torque, and power variations by examining the flow features in the near wake. While the hydrodynamic coefficients showed significant variations with changes in wall clearance and the Strouhal number (St), we did not observe significant variations with alterations in the Reynolds number (Re).

The construction of composite hydrogel evaporator with interfacial heating performance and its application in water treatment

To meet the needs of sewage cleaning and clean drinking water, a multifunctional photothermal device is designed in this paper, which mainly includes the non-infiltrating layer of copper stearate, bismuth tungstate and copper oxide composite hydrogel. By improving the synthesis process, sheet-like copper stearate and flower-like bismuth tungstate were prepared, realizing the load of canvas, felt and fabric, with the contact angles reaching 158º, 162º and 161º, respectively. The nonwetting layer has the performance of not only selective oil removal, but also mechanical stability. Through traditional non-infiltrating materials, dyes cannot be degraded, while with the introduction of bismuth tungstate, superhydrophobic materials are given photodegradation properties, thus solving the recovery problem of powder photocatalysts. The photodegradation stability was demonstrated via multiple photodegradation processes by calculating the reaction kinetic coefficient, with a degradation efficiency of greater than 90%. The position of valence (1.9 eV) and conduction (-0.735 eV) band of bismuth tungstate was calculated based on Mott-Schottky curve, DRS and VB-XPS. With the construction of copper oxide composite hydrogel, the mechanical stability was improved and an efficiency of 1.76 kg•m−2•h−1 was obtained. The composite hydrogel device can also be used to treat the aqueous solutions containing metal ions and dyes, which operates stably in aqueous solutions containing 3.5% NaCl without salt crystallization, thus proving the application value of the photothermal device.

Effects of Safety Climate and Employee Engagement towards Organisational Citizenship Behaviour of Sewage Workers

Manuscript type: Research paper Research aims: This study aims to investigate the effects of safety climate and employee engagement on organisational citizenship behaviour (OCB). Design/Methodology/Approach: Drawing from the social exchange theory and flow theory, a theoretical framework was developed and tested using data collected from 610 freelance sewage workers. A questionnaire survey was used to collect the data, while structural equation modelling (SEM) analysis was used as the data analysis approach. Research findings: The results reveal that both safety climate and employee engagement have significantly positive impact on employees’ organisational citizenship behaviour amongst sewage workers in Indonesia. This finding indicates that although the sewage cleaners are often employed based on contract and may not be in a position to demand more from the organisations, they do appreciate the organisational commitment in producing a safe workplace environment. They, in return will demonstrate a higher engagement towards their work. Theoretical contribution/Originality: This study contributes to the organisational citizenship behaviour literature by examining how workplace environmental factors such as safety climate affects organisational citizenship behaviour. In the context of sewage cleaning, safety climate is important, as sewage workers are frequently exposed to and threatened by serious health problems. Yet, there has been a paucity of research on the sewage cleaning sector to understand the relationships. Research limitation/Implications: The study implies that when organisations are willing to improve safety climate, their employees will perceive improved safety climate, and then will have more engagement and organisational citizenship behaviour.

ГОРОДСКОЕ ОБЩЕСТВО КАЗАНИ И САНИТАРНО-ЭКОЛОГИЧЕСКИЕ ПРОБЛЕМЫ ВО ВТОРОЙ ПОЛОВИНЕ XIX – НАЧАЛЕ XX ВЕКА

The attitude of the Kazan community to the urban environmental and sanitary problems during the second half of the 19th–early 20th centuries was discussed. The measures taken by the local government were analyzed. Based on the administrative sources and periodicals of that time, an ambiguous reaction to the governmental measures was noticed among the residents of Kazan, as compared with a similar situation in St. Petersburg. In Kazan, the residents intermittently violated the compulsory resolutions adopted by the local government to improve the environmental and sanitary situation: they kept the latrines dirty, failed to timely clean the street areas, and discharged their household wastes in the river waters. It was revealed that the residents tended to neglect the sanitary rules because of both irresponsibility and the difficult socioeconomic situation, i.e., sewage cleaning was expensive and complicated. Interestingly, the steps undertaken by the local government are quite confusing and questionable: on the one hand, the authorities did their best to prevent littering, deforestation, and sewage discharge; on the other hand, they were eager to solve the burning sanitary problems at the expense of the ecological well-being of the city.

Designing of an Immaculate Smart City with Cloud Based Predictive Analytics

The major objective of a smart city is to provide ripest and rightest services to its residents with minimal human intervention. The data collected from various sensors, receptors and receivers can be stored in a reliable, cost effective and manageable cloud storage. Predictive analytics such as predictive modelling and machine learning can be used to analyze the latest and past data from the cloud to forecast the near and far future. The predictive analytics will immediately send notifications and the appropriate actions to be taken to the concerned system so that the residents can get equable life. Waste management such as sewage management and trash management are one of the major exertion in a smart city. In this paper, predictive analytics is applied on the cloud data collected from various sensors attached on the waste management resources such as trash bins and sewage pipes. Firstly, group of trash bins and sewage pipes are attached with radio wave sensors which in turn connected to an IoT enabled receiver to provide cost effective data collection. Secondly, the data from the receivers are stored in a cloud. Thirdly, predictive analytics are proposed for applying on the data in the cloud. Finally, actions like redirecting the trash collection truck and sewage clearing robot based on the priority can be done automatically and long term actions can be directed to the concerned authorities with notifications and alerts to take necessary actions. In this paper, designing of an immaculate smart city is proposed which can be achieved by developing IoT based trash collection and sewage cleaning system. For analysis purpose synthetic data is considered where levels for garbage cleaning bins at different time are represented with different numbers.

Sewage cleaning by using a phase separator

This article proposes a solution to the urgent problem of treating oil-, fat-containing wastewater. A phase separator of dispersions for preliminary purification of industrial wastewater contaminated with fats is proposed, its effectiveness in the treatment of wastewater at local treatment facilities of an industrial plant for the production of sunflower oil is tested. In order to reduce the cost of acquiring reagents and increase the efficiency of purification of fat-containing wastewater, the use of carbide sludge and sodium hydroaluminate was studied. Laboratory studies conducted by the method of an active experiment.

Combined maintenance and routing optimization for large-scale sewage cleaning

The rapid population growth and the high rate of migration to urban areas impose a heavy load on the urban infrastructure. Particularly, sewerage systems are the target of disruptions, causing potential public health hazards. Although sewer systems are designed to handle some sediment and solid transport, particles can form deposits that increase the flood risk. To mitigate this risk, sewer systems require adequate maintenance scheduling, as well as ad-hoc repairs due to unforeseen disruptions. To address this challenge, we tackle the problem of planning and scheduling maintenance operations based on a deterioration pattern for a set of geographically spread sites, subject to unforeseen failures and restricted crews. We solve the problem as a two-stage maintenance-routing procedure. First, a maintenance model driven by the probability distribution of the time between failures determines the optimal time to perform maintenance operations for each site. Then, we design and apply an LP-based split procedure to route a set of crews to perform the planned maintenance operations at a near-minimum expected cost per unit time. Afterward, we adjust this routing solution dynamically to accommodate unplanned repair operations arising as a result of unforeseen failures. We validated our proposed method on a large-scale case study for sediment-related sewer blockages in Bogota (Colombia). Our methodology reduces the cost per unit time in roughly 18% with respect to the policy used by the city’s water utility company.

Development of Robotic Arm with Suction and Grinding Mechanism for Sewage Cleaning

Development of Robotic Arm with Suction and Grinding Mechanism for Sewage Cleaning

Ecological biotechnology of sewage cleaning

Ecological biotechnology of sewage cleaning

New-chitosan characterization and its bioassay in different salinity solutions using Artemia salina as bio tester

New chitosan powder extracted from eggs capsules of Rapana venosa and commercial chitosan powder were analyzed by spectral (UV–Vis) and color methods. The novelty of this study consists in the first time toxicity evaluation of the chitosan extracted from the walls of Rapana venosa eggs capsules. The evaluation was focused on the cytological behaviour of the new-chitosan particles in two different salinity conditions (3 and 35‰), at different concentrations, on bio tester organisms. The aim of this study was to determine the biological effect of the chitosan easily extracted from new marine sources and with a low financial effort. The experimental studies were performed by exposure of Artemia salina larvae, naupliar stage in saline chitosan solutions. The larvae were picked-up in 24 h time, after hatching and they were placed in the experimental recipients of 1 mL volume capacities, three repetitions were made for each test. The bioassay effects were recorded at 24 and 48 h after experiment started. The toxicity was indicated by the registration of larvae mortality, probably, induced by the cell growth inhibitions. The obtained results showed that the high toxicity effects could be observed at low concentrations of chitosan, in law salinity solutions. Due to this cytotoxicity variability, chitosan solutions could be useful in a wide range of applications (antifouling, biomedical or sewage cleaning).

Fabrication of Sewage Cleaning System

The thought process of the venture is to computerize the sewage cleaning process in seepage, to decrease the spreading of sicknesses to human. the dark water cleaning process counteracts bug pervasions by diminishing the buildups that can draw in and bolster bothers. It additionally enhances the time span of usability and tactile nature of sustenance items. In the proposed framework, the machine is worked with remote control to clean the sewage. Henceforth, this framework maintains a strategic distance from the effects from the sewage waste and its destructive gasses. this keeps the mosquito era from the wastage. the framework has a wiper engine that begins running when the set-up is exchanged on. two power window engines are associated with the haggle is driven with the assistance of the remote control set-up. the procedure begins gathering the sewage squanders by utilizing the arm and it tosses back the loss into the canister settled in the machine at the base. An arm is utilized to lift the sewage and thus a can is utilized to gather them. the set-up runs even in sewage zone with water (restricted to a specific sum) so the wastages which coasts on the water surface likewise get gathered. The trash which influences the waste is likewise grabbed and evacuated. This framework has restricted human intercession during the time spent cleaning and thusly decreases spreading of maladies to humankind.

Ecological Cleaning and Reusing of Wastewater. Possibilities, Advantages and Suggestions

In the article, it is analyzed historical view of sewage and rainwater cleaning, possibilities of applying it nowadays and newest experience in the world. After research, the main advantages and disadvantages of the system were revealed. There were two parts of the analysis: personal cleaning and territorial planning. Biological and mechanical filtration were mostly used types of water cleaning. Main problems of ecological cleaning and reusing of wastewater were found: rather big price, possibly permanent damage to the soil. DOI: http://dx.doi.org/10.5755/j01.sace.18.1.17557

Decade‐long time delays in nutrient and plant species dynamics during eutrophication and re‐oligotrophication of Lake Fure 1900–2015

Summary A central topic in nature conservation and ecological restoration is the potential of ecosystems to recover after the reduction of negative anthropogenic impacts. Often, protracted delays in biotic response to abiotic change have been observed. We analysed a unique long‐term data series in Lake Fure, Denmark, spanning the transformation from pristine environmental conditions in the early 1900s through a period (1920–1970) of eutrophication – from accelerating sewage input of phosphorus (P) – and subsequent re‐oligotrophication after sewage cleaning (1970–2015). We examine time delays between P inputs, in‐lake P concentrations and the richness and composition of submerged macrophyte communities. Lake P concentration exhibited decade‐long delays in response to periods of increasing or decreasing P inputs. It took 40 years and a 25‐fold increase in P input before P concentrations suddenly took off in the 1960s, reflecting profound sediment accumulation. Following reduced P input from c. 1970, it took 5 years before P concentrations showed the first signs of a decline. In 2014, water P concentration was still markedly higher than in 1931, despite much lower P inputs, because of elevated sediment release. Fifty years of eutrophication led to a reduction in aquatic macrophyte richness from 36 species to 12. Species’ responses were closely related to their growth strategy and depth distribution. Deep‐growing mosses, charophytes and short angiosperms disappeared, while tall angiosperms survived and pollution‐tolerant macroalgae colonized and spread. Subsequently, 45 years of oligotrophication led to clearer waters, macrophyte richness recovering to 28 species and some charophytes and short angiosperms reappearing. Dominance of pollution‐tolerant macroalgae persisted, however. Change in species dominance takes longer than colonization by new species. Synthesis. Time delays of P concentrations, water clarity and macrophyte richness and composition were long and complex. Neglecting growth strategies of species makes application of extinction debt and colonization credit concepts dubious, because numbers of oligotrophic species decrease and eutrophic species increase concomitantly during eutrophication and vice versa during oligotrophication. Although the original high species richness may be attained, it is unlikely that the original species composition is restored because many oligotrophic species have vanished from the regional species pool.

Design, Structural and Kinematic Analysis of Reconfigurable Sewage Cleaning Robot

Congested sewage system causes many health related problem, since every work activity bring sewage workers into contact with perilous and toxic substances while removing the clogs occurring in the system. The major illness includes not just associated the relatively mild case of gastroenteritis, but also the potentially fatal diseases such as leptospirosis and hepatitis. The aim of the project is to implement a robot to remove the choke in the sewage system at low cost and to completely eliminate the human engagement for this task. A robot of that nature could also be used in critical places where human workers cannot be employed to remove the clog because of physical limitations. An improved design incorporating the improvisations learnt from earlier versions of the developed robots is to be attempted in this project work. The performance of this robot is analyzed through multi body dynamics after incorporating the robot into the work environment. After finalizing the design through the analysis, the robot would be fabricated. Finally the evaluation of the robot performance in real-time would be performed through experimental tests. The control mode would be semi-autonomous initially and then would be made completely autonomous. For convenience, the robot can also be operated manually from outside the sewage system based on the environment and requirement.

Comprehensive Solution of Sewage Cleaning and Waste Utilization Ecological Problems

Absorption properties of ceramic workshop waste and mixtures with agricultural processing waste are studied. The efficiency of cleaning effluent from heavy metal cations is calculated. The surface microstructure of the absorbents obtained is considered.

Design and Development of a Reconfigurable Type Autonomous Sewage Cleaning Mobile Manipulator

The advances in robotics, in the last ten years, have enabled robot technology to solve many practical problems that humans encounter in day-to-day activities. But, even today manual scavenging of the sewage is practiced in urban areas of India, wherein man enter the manholes and clean the scales and clogs in the sewage pipelines manually with virtually no technical equipment. This practice might jeopardize the lives of humans; therefore, a sewage cleaning robot is essential to replace the human intervention. The conventional sewage cleaning robots available are not capable and effective in cleaning a variable diameter pipelines. In order to overcome this issue, an attempt has been is made to design and develop a reconfigurable type sewage cleaning mobile manipulator, which can efficiently clean the scales and clogs formed in the variable diameter sewage pipeline. A conceptual model of the manipulator has been created in solid model using solid works. It will give a clear understanding of the manipulator and its subsystem interactions. A prototype model of the manipulator has been developed based on the design concept and its working environment i. e, various goals that robot has to do after entering the sewage pipe and hence the functional requirements are finalized. It consists of various links and joints. The joints are drive through the various motors which are discussed in the paper. Preliminary investigations are carried out on the developed prototype model and some of the results are discussed in the paper.

Biodiversity and secretion of enzymes with potential utility in wastewater treatment

The main organic contaminants in municipal wastewater are proteins, polysaccharides, and lipids, which must be hydrolyzed to smaller units. A high concentration of oil and grease in wastewater affects biological wastewater treatment processes by forming a layer on the water surface, which decreased the oxygen transfer rate into the aerobic process. Microbial proteases, lipases, amylases, and celullases should play essential roles in the biological wastewater treatment process. The present study aimed to isolate lipase- and other hydrolytic enzyme-producing microorganisms and assess their degradation capabilities of fat and oil wastewater in the laboratory. We also evaluated microbial interactions as an approach to enhance lipolytic activity. We place emphasis on lipase activity because oil and grease are not only environmental pollutants, but also form an undesirable tough crust on pipes of sewage treatment plants. Thirty-five lipolytic microorganisms from sewage were identified and assessed for hydrolytic enzyme profiles. Lipases were characterized in detail by quantification, chain length affinity, and optimal conditions for activity. The good stability of isolated lipases in the presence of chemical agents, thermal stability, wide range of pH activity and tolerance, and affinity for different lengths of ester chains indicates that some of these enzymes may be good candidates for the hydrolysis of organic compounds present in wastewater. A combination of enzymes and fermenting bacteria may facilitate the complete hydrolysis of triglycerides, proteins, and lingo-cellulose that normally occur in the wastes of industrial processes. This study identifies enzymes and microbial mixtures capable of digesting natural polymeric materials for facilitating the sewage cleaning process.

SEROPREVALENCE OF LEPTOSPIROSIS AMONG HIGH-RISK POPULATION OF ANDAMAN ISLANDS, INDIA

Leptospirosis is a severe spirochetal zoonosis in the world. It is considered an occupational disease of persons engaged in agriculture, sewage works, forestry, and animal slaughtering. A study was conducted with an objective of assessing the seroprevalence of leptospirosis among the high-risk groups of Andaman Islands. A total of 611 sera samples from different high-risk populations were collected and tested by microscopic agglutination test (MAT). Genetic characterization of the isolate was done by randomly amplified polymorphic DNA (RAPD) fingerprinting, and serological characterization was done using monoclonal antibody technique. Antibodies to leptospires were detected in 322 samples giving an overall seroprevalence of 52.7%. The seroprevalence was highest among agriculture workers (62.5%) followed by sewage workers (39.4%), animal handlers (37.5%), forest workers (27.3%), and butchers (30.0%). Seroprevalence among control population was 14.7%, which was comparatively less than that of the high-risk population groups. Subject sera were most commonly reacted with organisms of the serogroup Grippotyphosa followed by Australis, and the pattern was similar in control group. Four leptospires were isolated from agriculture workers who were admitted to the public health center (PHC) with complaints of fever and body ache. Human isolates were compared with two rodent (Rattus norvegicus) isolates from the same area of agriculture workers to get initial information about the transmission cycle of leptospirosis in the study community. Randomly amplified polymorphic DNA fingerprinting pattern of the strains recovered from the rodents and human patients were identified as belonged to genomo-species Leptospira interrogans. The antigenic characterization of the strains recovered from them belonged to serovar Valbuzzi of serogroup Grippotyphosa. The study showed that people engaged in high-risk activities such as agriculture, sewage cleaning, animal handling, animal slaughtering, and forestry are frequently exposed to leptospirosis, and hence control strategies targeting these populations could be more effective.

Degradation of acrylic copolymers by Fenton's reagent

The degradation of different copolymers of acrylamide and acrylic acid by Fenton's reagent was studied. The polymers tested were either homopolymers or copolymers containing lignin sulfonate, guaiacol or 3,4-dihydroxylbenzoic acid, respectively. Acrylamide copolymers (PAAm) were degraded faster than polymers of acrylic acid (PAA). Among the PAAm, the copolymers of lignin sulfonate and guaiacol were degraded at a significantly higher rate than the corresponding homopolymer, whereas among the PAA, the rate of degradation was highest with copolymers of guaiacol and 3,4-dihydroxylbenzoic acid. The decrease of H 2O 2, i.e. the rate of hydroxyl radical production in the presence of a certain polymer, did not correlate with the rate of its degradation. It was concluded that the incorporation of lignin and certain phenolic compounds into an acrylic chain may accelerate the decay of these polymers by wood decaying fungi, which reportedly produce hydroxyl radicals extra-cellularly, and through the use of advanced oxidation systems applied in sewage cleaning.

Aggressive treatment, outcome and long time neurologic and pulmonary complications of lethal hydrogen sulphide (H2S) intoxication

Hydrogen sulphide poisoning can occur in industrial/occupational (oil refining, viscose rayon manufacturing, vulcanization of rubber, hydrochloric acid in farm wells, leather industry, sewage cleaning, roofing asphalt tanks, etc), recreational (cleaning of hot spring reservoirs, caves, sulfur springs, etc), or hospital (plaster of Paris, etc) settings. The first reports date from the 17th century where city sewage cleaners were found dead in the vicinity of the sewers. At a concentration of 0–25 ppm H2S has a specific odour of rotten eggs. This odour is an unreliable marker since at higher concentrations (> 100 ppm) the gas rapidly causes paralysis of (the olfactory system resulting in anosmia. At concentrations > 50 ppm symptoms are characterized by mucositis (conjunctivitis, upper airway irritation), nausea and dizziness, at > 200 ppm pulmonary edema can occur, at > 500 ppm neurologic problems arise (agitation, seizures followed by coma), at > 1000 ppm sudden death can occur. Main target organs are the central nervous system (CNS) and the respiratory system. Acute high dose intoxication mainly results in CNS problems whereas chronic lower dose intoxication results in acute lung injury (ALI) or acute pulmonary edema, the latter carrying a worse prognosis. There is still a great controversy in the literature about the best treatment and little is known about long time CNS and pulmonary complications in survivors.