scholarly journals Gasification of yeast industry treatment plant sludge using downdraft Gasifier

2017 ◽  
Vol 77 (2) ◽  
pp. 364-374 ◽  
Author(s):  
Azize Ayol ◽  
Ozgun Tezer ◽  
Alim Gurgen

Abstract Sludges produced in biological wastewater treatment plants have rich organic materials in their characteristics. Recent research studies have focused on the energy recovery from sludge due to its high organic content. The gasification process is a thermal conversion technology transforming the chemical energy contained in a solid fuel into thermal energy and electricity. The produced syngas as a mixture of CO, CH4, H2 and other gases can be used to generate electrical energy. The gasification of yeast industry sludge has been experimentally evaluated in a pilot scale downdraft-type gasifier as a route towards the energy recovery. The gasifier has 20 kg biomass/h fuel capacity. During gasification, the temperature achieved was more than 1,000°C in the gasifier, and then the syngas was transferred to the gas engine to yield the electricity. A load was connected to the grid box and approximately 1 kWh electrical power generation for 1 kg dry sludge was determined. The characteristics of residuals – ash, glassy material – were also analyzed. It was found that most of the heavy metals were fixed in the glassy material. Experimental results showed that the yeast industry sludge was an appropriate material for gasification studies and remarkable energy recovery was obtained in terms of power production by using syngas.

2000 ◽  
Vol 41 (1) ◽  
pp. 57-63 ◽  
Author(s):  
S. Vandaele ◽  
C. Thoeye ◽  
B. Van Eygen ◽  
G. De Gueldre

In Flanders (Belgium) an estimated 15% of the population will never be connected to a central wastewater treatment plant (WWTP). Small WWTPs can be a valuable option. Aquafin bases the decision to build SWWTPs on a drainage area study. To realise an accelerated construction the process choice is made accordingly to a standard matrix, which represents the different technologies in function of the size and the effluent consents. A pilot scale constructed two-stage reed bed is used to optimise the concept of the reed beds. The concept consists of a primary clarifier, two parallel vertical flow reed beds followed by a sub-surface flow reed bed. The removal efficiency of organic pollutants is high (COD: 89%, BOD: 98%). Phosphorus removal is high at the start-up but diminishes throughout the testing period (from 100% to 71% retention after 7 months). Nitrogen removal amounts to 53% on average. Nitrification is complete in summer. Denitrification appears to be the limiting factor. In autumn leakage of nitrogen is assumed. Removal efficiency of pathogens amounts to almost 99%. Clogging forms a substantial constraint of the vertical flow reed bed. Problems appear to be related with presettlement, feed interval and geotextile.


2017 ◽  
Vol 6 (1) ◽  
pp. 58-65
Author(s):  
Тумашев ◽  
R. Tumashev ◽  
Щеголев ◽  
N. Schegolev ◽  
Назаревич ◽  
...  

Improving the ecological condition of water basins is closely connected with reconstruction of systems for water disposal and wastewaters treatment. Modernization of old-fashioned wastewater treatment plants, and operating cost saving is possible by means of transition to effective technological solutions, including the process of substrate anaerobic digestion with production of biogas and raw material for high-quality fertilizers. Biogas can be used in power stations for production of thermal and electrical energy required for wastewater treatment plant needs. This energy also reduces the plant’s operating cost. A scheme of a module for anaerobic digestion has been proposed, and application of utilization cogeneration gas-turbine units with an external supply of warmth to cyclic air has been justified. Optimum parameters of utilization gas-turbine units have been determined. At air temperature in front of the turbine 1190 K the compression ratio in a cycle is equal to 4,2, electric efficiency — 0,313, the general one taking into account the developed warmth — 0,872. In some cases the gas-turbine unit can be manufactured without booster fuel compressor.


2002 ◽  
Vol 45 (4-5) ◽  
pp. 151-158 ◽  
Author(s):  
A. Abusam ◽  
K.J. Keesman ◽  
H. Spanjers ◽  
G. van Straten ◽  
K. Meinema

This paper presents validation and implementation results of a benchmark developed for a specific full-scale oxidation ditch wastewater treatment plant. A benchmark is a standard simulation procedure that can be used as a tool in evaluating various control strategies proposed for wastewater treatment plants. It is based on model and performance criteria development. Testing of this benchmark, by comparing benchmark predictions to real measurements of the electrical energy consumptions and amounts of disposed sludge for a specific oxidation ditch WWTP, has shown that it can (reasonably) be used for evaluating the performance of this WWTP. Subsequently, the validated benchmark was then used in evaluating some basic and advanced control strategies. Some of the interesting results obtained are the following: (i) influent flow splitting ratio, between the first and the fourth aerated compartments of the ditch, has no significant effect on the TN concentrations in the effluent, and (ii) for evaluation of long-term control strategies, future benchmarks need to be able to assess settlers' performance.


2018 ◽  
Vol 34 ◽  
pp. 02037 ◽  
Author(s):  
M.A. Che Munaaim ◽  
N. Razali ◽  
A. Ayob ◽  
N. Hamidin ◽  
M.A. Othuman Mydin

A micro hydroelectric generator is an energy conversion approach to generate electricity from potential (motion) energy to an electrical energy. In this research, it is desired to be implemented by using a micro hydroelectric generator which is desired to be embedded at the continuous flow of effluent discharge point of domestic sewerage treatment plant (STP). This research evaluates the potential of electricity generation from micro hydroelectric generator attached to 30,000 PE sewerage treatment plant. The power output obtained from calculation of electrical power conversion is used to identify the possibility of this system and its ability to provide electrical energy, which can minimize the cost of electric bill especially for the pumping system. The overview of this system on the practical application with the consideration of payback period is summarized. The ultimate aim of the whole application is to have a self-ecosystem electrical power generated for the internal use of STP by using its own flowing water in supporting the sustainable engineering towards renewable energy and energy efficient approach. The results shows that the output power obtained is lower than expected output power (12 kW) and fall beyond of the range of a micro hydro power (5kW - 100kW) since it is only generating 1.58 kW energy by calculation. It is also observed that the estimated payback period is longer which i.e 7 years to recoup the return of investment. A range of head from 4.5 m and above for the case where the flow shall at least have maintained at 0.05 m3/s in the selected plant in order to achieved a feasible power output. In conclusion, wastewater treatment process involves the flowing water (potential energy) especially at the effluent discharge point of STP is possibly harvested for electricity generation by embedding the micro hydroelectric generator. However, the selection of STP needs to have minimum 4.5 meter head with 0.05 m3/s of continuously flowing water to make it feasible to harvest.


This Study Was Made To Study The Use Of Circular Aeration Tanks Instead Of Rectangular One In Wastewater Treatment Plants. The Study Covered The Effect Of Tank Geometric Shape On Action Stability, Effective Parameters Homogeneity And Treatment Efficiency Inside The Aeration Tank And Its Reflection On The Final Sedimentation Tank Performance. A Pilot Scale Was Erected In Balaqs Wastewater Treatment Plant Pilot Consists From Two Lines One Circular Aeration Tank Followed By Final Settling Tank And Second Rectangular Aeration Tank Followed By Final Settling Tank For Comparison Purpose Under The Same Conditions. The Samples Were Taken Continuously For 5 Weeks From The Inlet, Outlet For (Bod, & Tss) To Measure The Aeration Removal Efficiency. Also Measurements Inside Both Types Of Aeration Tanks To Determine The Parameters Of Temperature & Do Distribution And Stability In Different Depths And Sides Of Tank. Also The Consumed Power Had Been Measured. The Results Shows That The Circular Aeration Tank Achieved Better Stability Inside The Tank With Minimal Variation In Both Of Do And Temperature That Varied Widely In The Rectangular Tank Between Different Depths And Also Longitudinally And In Cross Section Directions That Affects Mainly On The Tank Efficiency And The Consumed Power Needed For Surface Aerators Operation. The Circular Safe About 50% Of The Consumed Power That Also Safe In The Construction And Operation Costs For Such Treatment.


1996 ◽  
Vol 33 (1) ◽  
pp. 25-35 ◽  
Author(s):  
A. Lynggaard-Jensen ◽  
N. H. Eisum ◽  
I. Rasmussen ◽  
H. Svankjær Jacobsen ◽  
T. Stenstrøm

Sensor prototypes for measurement of ammonium, nitrate and phosphate in wastewater treatment plants are described together with the results obtained in laboratory and pilot scale wastewater treatment plants. A functional description of the sensor principles is presented together with the installation and operation procedures. Basically the measurements are done using membrane technology in combination with semi-micro Continuous Flow Analysis (μCFA) with classic colorimetry. Because of this the sensors can be installed directly in the aeration tanks without any need for sampling, filtration, etc. Furthermore, the semi-micro scale is used in such a way, that handling of chemicals and waste is a closed loop in a package to be changed once a month. The sensors have been tested thoroughly in a pilot scale waste water treatment plant (recirculation) using real raw wastewater as well as artificial wastewater. The sensors have been placed directly in the aeration tank or in the anoxic tank of the pilot plant. The tests show very little, if any, fouling problems due to the membrane material used. The test results show a good reproducibility and most important, compared to other available sensors/analyzers on the market, very low response times, less than 5 minutes. Owing to these low response times, experiments with direct measurement of nitrification and denitrification rates were carried out.


1998 ◽  
Vol 37 (9) ◽  
pp. 151-158
Author(s):  
Dieter Schreff ◽  
Peter A. Wilderer

Systems in which denitrification follows nitrification (post-denitrification) copy the natural sequence of nitrogen removal. The disadvantage of post-denitrification, however, is that an external carbon source must be added to the denitrification reactor. In the concept discussed in this paper, excess sludge from a high loaded activated sludge plant is used as carbon source and as source of denitrifiers in a three-stage system. The sludge is fed into a anoxic reactor placed in between the nitrification reactor (e.g., trickling filter) and the final clarifier. Two different operation methods were investigated at a pilot-scale system set up at the Ingolstadt wastewater treatment plant. Low nitrate effluent values were obtained at high sludge feeding rates, but at the expense of a significant increase in turbidity and NH4-N effluent concentrations. This problem could be solved by a reduction of the sludge feeding rate and by applying intermittent feeling. The effluent turbidity was kept at an acceptable level, but denitrification was relatively slow in progress. To achieve both low effluent turbidity and low nitrate discharge, a combination of pre- and post-denitrification is recommended.


2021 ◽  
Author(s):  
◽  
Tolulope Adewale Kudoro

Hydropower is a source of renewable energy. It is possible to combine a hydropower installation with an existing wastewater plant while ensuring it still performs its basic purpose. The multipurpose scheme would be integrated into the facility to generate hydropower while also fulfilling its primary role of treating wastewater. The wastewater plant can generate renewable energy and benefit from introducing microturbines. The turbine system is moved by the power in the flowing treated water that is transformed into mechanical energy which rotates the generator and in turn generates electrical power. In this work, the potential for power generation from the energy in the outflow along with the economics of the system in wastewater plants in the state of Missouri was investigated to improve the energy efficiency of the municipal wastewater treatment plants. Data like the daily flow rate, speed of flow, available head, etc about the wastewater plants in Missouri were collected and some interviews held with plant managers of the wastewater treatment plants. The investigation revealed that there are 127 wastewater treatment plants in the state of Missouri with 32 plants discharging less than 1 Mgd, 74 plants discharging between 1 Mgd and 5 Mgd, 13 plants discharging between 5 Mgd and 20 Mgd while just 8 plants had an outflow between 20 Mgd and 120 Mgd range. The flowrate helps in calculating and determining the theoretical and actual amount of power that can be gotten from the micro hydropower system in the wastewater treatment plant. For the actual amount of power gotten, the efficiency factor (efficiency of the turbine, and efficiency of the generator) of the generating system is considered. A brief study on the turbine system was conducted and a crossflow turbine was selected as the most suitable for the wastewater treatment plant as a vast majority of them had low head and high flow capacity. The analysis showed that out of the 127 wastewater treatment plants in the state of Missouri, only 21 treatment plants have the maximum potential to generate power and reduce operating costs. Also, two plants were selected for case studies. The operating cost is reduced because of the decrease in demand for electrical power from the grid. The 21 treatment plants have a daily outflow between 5Mgd to 120Mgd and could produce power through an axial flow turbine that utilizes the kinetic energy in the flow volume.


Revista EIA ◽  
2013 ◽  
Vol 6 (11) ◽  
pp. 21
Author(s):  
Patricia Torres ◽  
Carlos Madera ◽  
Jorge Silva

Uno de los principales problemas de calidad que presentan los biosólidos de plantas de tratamiento de aguas residuales domésticas –PTAR– es el contenido de microorganismos patógenos que los clasifica en muchos casos como Clase B con restricción para uso agrícola. Este estudio evaluó la estabilización alcalina de los biosólidos de la PTAR Cañaveralejo (Cali, Colombia) para mejorar su calidad microbiológica, empleando dos tipos de cal (hidratada y viva) en dosis entre 8 y 25 % y dos tipos de ceniza con dosis entre 8 y 40 % en unidades experimentales de 0,2 m2 con un tiempo de contacto de 13 días. Los resultados mostraron que con cal se logró reducción total de las variables de respuesta evaluadas (coliformes fecales, Salmonella sp y huevos de helmintos), mientras que el poder alcalinizante de las cenizas evaluadas fue insuficiente. El biosólido higienizado con cal presenta alto potencial de uso agrícola por su calidad microbiológica y por el contenido final de materia orgánica y nutrientes (N, P) que pueden beneficiar los suelos, pero es recomendable evaluar la optimización a escala piloto de la dosificación de cal y la aplicación del biosólido en diferentes tipos de suelos y cultivos para precisar los beneficios o medidas preventivas antes de la aplicación.Abstract: One of the main quality problems of biosolids from domestic wastewater treatment plants –WWTP– is the high concentration of pathogens, often classified as a class B, with restriction for use in agriculture. This study evaluated the alkali stabilization of biosolids from Cañaveralejo wastewater treatment plant (PTAR-C), located in Cali, Colombia, in order to improve their microbiological quality using two types of lime (quick and hydrated) with doses between 8 to 25 % and two types of ash with 8 to 40 % as doses, in experimental units 0,2 m2with 13 days of contact time. The results showed that both type of lime reached the total reduction of evaluated monitoring variables (faecal coliforms, Salmonella sp, helmints eggs) while the alkali power of ashes were lower. The obtained biosolids treated with lime have a high potential use in agriculture purposes for the good microbiological quality, and for the organic matter and nutrient content (N, P) that can generate benefit to the soil, but it is recommendable to evaluate at pilot scale the lime doses and application of biosolid in different soils types and crops in order to precise the benefits or prevent measurements before application of material in soil.


2016 ◽  
Vol 18 (1) ◽  
pp. 108-118 ◽  

<div> <p>Slaughterhouse wastewaters are characterized by a high organic content, mainly composed of proteins and fats. Therefore, these wastewaters should be treated efficiently prior to discharge into receiving bodies to avoid severe environmental pollution. This work aimed to characterize slaughterhouse wastewater generated in one province of Iran (Khuzestan), evaluating various suitability of biological treatment, assessing wastewater treatment plants performance and feasibility of wastewater reuse. Composite samples were collected from input and output of wastewater treatment plant during 6 months (spring and summer) and were analyzed for TSS, turbidity, temperature, conductivity, pH, COD, BOD<sub>5</sub>, fat, total coliform and fecal coliform. Data analysis was done using Excel and SPSS software. The results showed that different quantities of wastewater were generated in any slaughterhouses of Ahvaz (120-600 l/d.sheep), Dezful (110-550 l/d.sheep), and Shushtar (139-694 l/d.sheep). Khuzestan slaughterhouses wastewater is classified by pollution severity as strong wastewater. The BOD<sub>5</sub>/COD ranges from 0.3 to 0.5, which indicates applicability of biological treatment. Wastewater treatment plant of Ahvaz with anaerobic stabilization ponds and extended aeration activated sludge process has the highest removal efficiencies of pollutants. The result also indicated reuse of slaughterhouses effluent was not acceptable due to not comply with the standards of Iran. Finally, if safe use or disposal of these effluents is desired, blood capture from raw wastewater for reducing the amounts of organic loading must be implemented. Also, use of an appropriate treatment plant is noted.</p> </div> <p>&nbsp;</p>


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