Emptying Of Tank Research Articles

Excreta flow mapping along the sanitation service chain, a case of Kombolcha town, Ethiopia

Poor management of fecal sludge (FSM) presents significant risks to public health and the environment. This study employed qualitative and quantitative data collection methods, along with the Shit Flow Diagram (SFD) data analyzing tool to investigate FSM patterns in Kombolcha town, Ethiopia. The findings indicate that 75.7% of housing unites in the town are shared toilets, with multiple households sharing a single facility. The primary toilet technologies used include cistern flush toilets (2.1%), pour/manual flush toilets (19.8%), ventilated improved pit latrines (11.1%), pit latrines with slabs (56.4%), and pit latrines without slabs (10.6%). However, 98.5% of these toilet types had either unlined or only partially lined containments. Furthermore, only 37% of households practice safe pit or sludge tank emptying. As a result, only 17% of fecal sludge goes through the sanitation value chain and is effectively treated, while 39% remains onsite and unemptied, and the remaining 44% is disposed of in a manner that poses risks to the environment and public health. The study highlights the significant public health and environmental risks associated with the high reliance on shared toilets, the prevalence of inadequately lined toilet types, and the low adoption of proper fecal sludge management practices. Addressing these challenges requires the implementation of sanitation bylaws and building code regulations that prioritize hygienic standards and promote improved toilet technologies.

Generalized energy model of the open thermodynamic system “vehicle fuel tank”. Processes of non-stationary heat transfer with a variable fuel mass

Introduction (statement of the problem and relevance). While gasoline-powered vehicles generate a significant amount of hydrocarbons in the form of the fuel system emitted vapors, the main element of the system being the fuel tank, modern requirements for evaporative emission limits are significantly tightened. At the same time, the vaporization process parameters and the fuel vapor amount are determined by the dynamics of fuel heating in the tank under various modes of vehicle operation.The purpose of the research was to develop a “vehicle fuel tank” energy model, seeking to create an open thermodynamic system which can exchange matter and energy with the environment depending on the variable amount of fuel in the tank.Methodology and research methods. The analysis of heat flush connected to the fuel tank and taken away from it was being carried out. As a result of solving equations for open and closed thermodynamic systems, the parameters characterizing the thermal properties of the fuel tank were obtained.Scientific novelty and results. Additional complex parameters have been proposed, the main of which are: heat transfer of the tank; tank heat capacity; supplied heat flux; the rate of heat capacity change; tank emptying time; fuel heating acceleration factor; the maximum rate of change in temperature difference. To assess the heat and power properties of the fuel tank, an additional parameter of the sphere surface area ratio to the surface area of the same volume tank has been proposed, which allowed estimating the fuel tank heat transfer to the environment.Practical significance. Equations have been obtained that allow estimating the level of fuel temperature depending on the thermal properties and shape of the fuel tank in the absence and presence of fuel pump control.

Risk estimation of risk of oil spill on the environment and its consequences

The paper considers the aspects of risk estimation of oil spills on the environment and its consequences. The results of emergency emptying of oil tank in various rates of filling have been studied. The data analysis for the whole cycle of tank operation showed that the harm from the emergency emptying of the tank with average filling is less than its standard value. The necessity of scale evaluation of consequences in the specification of the risk of emergency oil spill is marked as well.

Safely Managed On-Site Sanitation: A National Assessment of Sanitation Services and Potential Fecal Exposure in Indonesia.

Sustainable Development Goal target 6.2 calls for universal access to adequate and equitable sanitation, setting a more ambitious standard for ‘safely managed sanitation services’. On-site sanitation systems (e.g., septic tanks) are widely used in low- and middle-income countries (LMICs). However, the lack of indicators for assessing fecal exposure risks presents a barrier to monitoring safely managed services. Furthermore, geographic diversity and frequency of disasters require a more nuanced approach to risk-informed decision-making. Taking Indonesia as an example, the purpose of this paper is to provide insights into current status and practices for on-site sanitation services in the contexts of LMICs. Using a dataset from a national socio-economic survey (n = 295,155) coupled with village census (n = 83,931), we assessed (1) household sanitation practices across Indonesia stratified by city-level population density and meteorological factors, (2) factors associated with septic tank emptying practice, and (3) inequalities in potential fecal exposure as measured by population density and WASH access by wealth quintile. We found a high reliance on on-site sanitation facilities (80.0%), almost half of which are assumed to be ‘uncontained’ septic tanks and one in ten facilities discharging untreated waste directly into the environment. The most densely populated areas had the highest rates of septic tank emptying, though emptying rates were just 17.0%, while in the lowest population density group, emptying was rarely reported. Multivariate regression analysis demonstrated an association between flooding and drought occurrence and septic tank emptying practice. Higher groundwater usage for drinking among poorer households suggests unsafe sanitation may disproportionally affect the poor. Our study underscores the urgent need to strengthen the monitoring of on-site sanitation in LMICs by developing contextualized standards. Furthermore, the inequalities in potential fecal exposure require greater attention and tailored support mechanisms to ensure the poorest gain access to safely managed sanitation services.

Effect of increasing levels of corn silage in an alfalfa-based dairy cow diet and of manure management practices on manure fugitive methane emissions

The main objective of this study was to assess the effect of dairy cow diets and manure storage management practices on manure fugitive CH4 emission in order to precisely establish the carbon footprint of Canadian milk products. The specific objectives of this study were to investigate the effect of incorporating 50 and 100% corn silage (CS) as starch sources in dairy cow diets and the effect of complete removal of residual sludge in the manure storage tank and of storage emptying frequency on manure fugitive CH4 emissions. Alfalfa silage based diets were formulated as follows: 0% corn silage (0% CS, considered as the control diet); 50% corn silage (50% CS); and 100% corn silage (100% CS). Canadian summer manure storage conditions were simulated in laboratory-scale storage structures located in a controlled-environment chamber operated at 20±1°C. The incorporation of 50 and 100% CS in dairy diets was associated with significant increases of 39 and 79%, respectively, in fugitive CH4 emissions expressed in Lday−1cow−1 from manure storage with residual sludge over a 120-day storage period. The complete removal of residual sludge in the manure storage tank resulted in fugitive methane emission reductions exceeding 97.0% irrespective of the diet composition. Emptying of the manure storage tank 2 times and 4 times over the summer period reduced fugitive CH4 emissions on average by 40 and 80%, respectively. The complete removal of the manure storage residual sludge and the increase in manure storage tank emptying frequency over the summer can be adopted as low-cost best management practices (BMPs) for substantially reducing the fugitive CH4 emissions from manure storages.

Characterisation of retention tank water quality: particle settling velocity distribution and retention time

Retention tanks (RTs) are commonly used to reduce combined sewer overflows, management of which is an important way of reducing the impacts of urban development on receiving waters. However, overflow characteristics and the processes affecting them are not yet fully understood. In a context of integrated urban wastewater systems, the management of RTs is mainly done to satisfy hydraulic constraints even if the idea behind such structures is to limit the discharge of pollutants to the environment. This study reports new insights in the settling processes and the pollutant behaviour occurring in an off-line RT. The authors first focus on the total suspended solids (TSS) and the total chemical oxygen demand (CODt) dynamics at the inlet and the outlet of a RT. Secondly, they focus on the possible relationship between the variation of the particle settling velocity distribution of particles and the TSS concentration dynamics. Finally, analyses of the TSS and CODt concentration evolution during tank emptying give information on the interaction between wastewater retention time and the settling performance.

Characterization of the potential impact of retention tank emptying on wastewater primary treatment: a new element for CSO management

Theoretical studies have shown that discharges from retention tanks could have a negative impact on the WWTP's (Wastewater Treatment Plant) effluent. Characterization of such discharges is necessary to better understand these impacts. This study aims at: (1) characterizing water quality during emptying of a tank; and (2) characterizing the temporal variation of settling velocities of the waters released to the WWTP. Two full-scale sampling campaigns (18 rain events) have been realized in Quebec City and laboratory analyses have shown a wide variability of total suspended solids (TSS) and Chemical Oxygen Demand (COD) concentrations in the water released from the tank. Suspended solids seem to settle quickly because they are only found in large amounts during the first 15 min of pumping to the WWTP. These solids are hypothesized to come from the pumping in which solids remained after a previous event. When these solids are evacuated, low TSS containing waters are pumped from the retention tank. A second concentration peak occurs at the end of the emptying period when the tank is cleaned with wash water. Finally, settling velocity studies allowed characterizing combined sewer wastewaters by separating three main fractions of pollutants which correspond to the beginning, middle and end of emptying. In most cases, it is noticed that particle settling velocities increase as the pollutant load increases.

A simple system for self-cleaning of fish rearing tanks by periodic increase in water outflow

A system for effective removal of surplus food and fecal residues in fish rearing tanks is described. The system utilizes the siphon principle known from laboratory pipette washers, and is designed to work with the outflow of water through the center bottom outlet of the tank. When the siphon system is at work, all accumulated debris will be removed into the drain. A total emptying of tank by the siphon is avoided by breaking the outflow water column by an inlet of air. Air is introduced into the water column of the siphon at an appropriate water level by a narrow tube connected through the sidewall of the tank. Combined with a circular water current in the tank and a declining bottom toward the center, the system will effectively remove organic waste accumulated within each filling cycle of water. The biological advantages from periodic changes in water speed within fish rearing tanks is discussed.

Radioactive Effluent Treatment Plant—Sellafield Reprocessing Factory

This paper outlines the reprocessing of spent radioactive fuel at the British Nuclear Fuels plant, Sellafield, and describes the development, construction and commissioning of a new site ion exchange effluent plant (SIXEP). Gives details of the processes involved including the ion exchange columns, the ion exchanger, the carbonating tower, the waste storage tanks, the tank emptying system, and pumps and valves Reviews the initial operation of the plant and discusses future developments in radioactive waste treatment.