Dried Municiple Sewage Sludge Gasification Experiment in Dual Fluidized Bed

2011 ◽  
Vol 383-390 ◽  
pp. 3799-3804
Author(s):  
Xiao Xu Fan ◽  
Lei Zhe Chu ◽  
Li Guo Yang

The fuel characteristics of municipal sewage sludge are suitable for dual fluidized bed(DFB) gasification, which can get middle calorific value gas through volatile pyrolysis, and reduce volume through char combustion. The hot test results of municipal sewage sludge on DFB rig were showen that the temperature distribution along combustor heigh is uniform, and the carbon content of fly ash is about 2~3%. In the experiment, with the increase of gasifier temperatrue, the more volatile of the sewage sludge was pyrolyzed. When the temperature of the gasifier reached 800°C, the calorific value of gas was 6.9MJ/Nm3; the emissions of SO2, NOx and HCl were appropriate to the standard. The leaching toxicity of heavy metal of the fly ash was lower than the discharge standard.

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3106
Author(s):  
Tomasz Kalak ◽  
Kinga Marciszewicz ◽  
Joanna Piepiórka-Stepuk

Recently, more and more attention has been paid to the removal of nickel ions due to their negative effects on the environment and human health. In this research, fly ash obtained as a result of incineration of municipal sewage sludge with the use of circulating fluidized bed combustion (CFBC) technology was used to analyze the possibility of removing Ni(II) ions in adsorption processes. The properties of the material were determined using analytical methods, such as SEM-EDS, XRD, BET, BJH, thermogravimetry, zeta potential, SEM, and FT-IR. Several factors were analyzed, such as adsorbent dose, initial pH, initial concentration, and contact time. As a result of the conducted research, the maximum sorption efficiency was obtained at the level of 99.9%. The kinetics analysis and isotherms showed that the pseudo-second order equation model and the Freundlich isotherm model best suited this process. In conclusion, sewage sludge fly ash may be a suitable material for the effective removal of nickel from wastewater and the improvement of water quality. This research is in line with current trends in the concepts of circular economy and sustainable development.


2011 ◽  
Vol 374-377 ◽  
pp. 18-23 ◽  
Author(s):  
Hai Bo Wang ◽  
Zi Zeng Lin ◽  
Zhong Yi He

Series of experimental tests on the forming technique, sintering technique, performance and effectiveness of a new fired brick by mixing municipal sewage sludge and shale are carried out. Test results show that adding sludge properly in the process of manufacture shale fired common brick is feasible. Along with increase of sludge content, the compacting of uniformity of unburned brick decreased and its porosity increased. When shale-sludge mixtures were calcined, the heavy metal solidified, the ignition lost and organic substance volatilized that reduced the unconfined compressive strength (UCS) of the brick and improve its thermal insulation ability. The phase composition and leaching toxicity of sewage sludge-shale baked brick can be up to national standard. Good quality brick can be produced by blending mixture with the optimum moisture content (OMC) 18.0%-20.0%, drying at 105°C and sintering at 960°C. With all being considered in manufacturing brick, the content of sewage sludge shall be controlled within 9.0% that can make UCS of the new brick reach MU10 criterion and it has a superior heat preservation effect to normal brick from clay or shale alone.


RSC Advances ◽  
2021 ◽  
Vol 11 (36) ◽  
pp. 21964-21978
Author(s):  
Tomasz Kalak ◽  
Yu Tachibana

Fly ash and slag were produced as a result of the incineration of municipal sewage sludge using the circulating fluidized bed combustion (CFBC) technology and were examined for the simultaneous recovery of lithium and uranium from seawater in batch adsorption experiments.


2018 ◽  
Vol 26 ◽  
pp. 00004
Author(s):  
Arkadiusz Ostojski

This paper aims to present municipal sewage sludge (MSS) elementary analysis and energetic potential based on measurement of heat of combustion (higher heating value HHV) and calculation of calorific values (lower heating value LHV). The analysis takes into the consideration water content in sewage sludge, at different utilization stages, in wastewater treatment plants in Gdańsk Wschód and Kościerzyna – Pomeranian Voivodeship. The study yielded the following results (in % dry matter): ash 19÷31 %, C - 31÷36 %, H - 5÷6 %, N - 4÷6 %, O - 28÷32 %, S – 1 %. Calorific value of stabilized sludges in Gdańsk was on average 13.8÷15 MJ/kg. In case of sludges not undergoing digestion from Kościerzyna WWTP, the calorific value was at the level of 17.5 MJ/kg. Thus, sewage sludges are good energy carriers. High water content though is the problem, as it lowers the useful effect of heat. There is no alternative for thermal sewage sludge neutralization, which is in conformity with valid Polish National Waste Management Plan (KPGO 2022).


Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 487 ◽  
Author(s):  
Gabriela Rutkowska ◽  
Piotr Wichowski ◽  
Małgorzata Franus ◽  
Michał Mendryk ◽  
Joanna Fronczyk

This article focuses on the impact of fly ash from the combustion of municipal sewage sludge (FAMSS) as a cement additive in the amounts of 5%, 10%, 15%, 20% and 25% (by mass) on selected concrete properties. In the course of the experimental work, water penetration depth and compressive strength measurements were made at various periods of curing (from 2 to 365 days). In addition, the potential impact of FAMSS on the natural environment was examined by determining the leachability of heavy metals. FAMSS-modified concretes showed small values of water penetration depth (lower than 50 mm), as well as good compressive strength (reaching minimum class C30/37 after 130 days of maturing)—similar to the compressive strength obtained for conventional concrete. In addition, the partial replacement of cement with FAMSS has environmental benefits, expressed as a reduction in CO2 emissions. In addition, study has shown that compliance with environmental requirements is associated with heavy metal leaching.


Author(s):  
Xiao-Ping Chen ◽  
Li-Feng Gu ◽  
Chang-Sui Zhao ◽  
Ai-Qiang Zhu ◽  
Xin Sun

With the rapid economic development and the increase in population in the whole world, the amount of municipal sewage (MS) is increasing and lead to a rapid increasing in amount of municipal sewage sludge (MSS). Combustion of municipal sewage sludge may be a viable solution for its disposal in some cases and so is its co-combustion with coal. Whereas significant information is available on NOx and N2O emissions characteristics of sludge and coal individually, not much has been reported on sludge/coal blends. In the present paper, investigations in NOx and N2O emission characteristics from circulation fluidized bed combustion of blends of municipal sewage sludge and coal were conducted in a 0.2MWth circulating fluidized bed test facility with cross section of 0.23×0.23m2 and height of 5.9m. Coal sample selected was a kind of lignite, while a kind of paper mill sludge was used as sludge sample. The influences of sludge/coal mixing rate, excess air ratio and second air ratio on NOx and N2O emission characteristics have been studied. Test results show that co-combustion of sewage sludge and coal is feasible. With the increasing in proportion of sludge of the sludge/coal blends, the temperatures in dense bed and freeboard decrease rapidly, and the emissions of NOx decrease while the emission of N2O increases obviously. With the increasing in excess air ratio, the emission concentrations of NOx and N2O increase. While with the increasing in secondary air ratio, the emission concentrations of NOx and N2O decrease.


2020 ◽  
Vol 396 ◽  
pp. 122619 ◽  
Author(s):  
Yang Liu ◽  
Chunmei Ran ◽  
Asif Ali Siyal ◽  
Yongmeng Song ◽  
Zhihui Jiang ◽  
...  

2016 ◽  
Vol 63 (1) ◽  
pp. 47-61 ◽  
Author(s):  
Paweł Falacinski ◽  
Łukasz Szarek

Abstract In Poland, in recent years, there has been a rapid accumulation of sewage sludge - a by-product in the treatment of urban wastewater. This has come about as a result of infrastructure renewal, specifically, the construction of modern sewage treatment plants. The more stringent regulations and strategic goals adopted for modern sewage management have necessitated the application of modern engineering methodology for the disposal of sewage sludge. One approach is incineration. As a consequence, the amount of fly ash resulting from the thermal treatment of municipal sewage sludge has grown significantly. Hence, intensive work is in progress for environmentally safe management of this type of waste. The aim of the experiment was to evaluate the possibility of using the fly ash that results from municipal sewage sludge thermal treatment (SSTT) as an additive to hardening slurries. This type of hardening slurry with various types of additives, e.g. coal combustion products, is used in the construction of cut-off walls in hydraulic structures. The article presents the technological and functional parameters of hardening slurries with an addition of fly ash obtained by SSTT. Moreover, the usefulness of these slurries is analysed on the basis of their basic properties, i.e. density, contractual viscosity, water separation, structural strength, volumetric density, hydraulic conductivity, compressive and tensile strength. The mandated requirements for slurries employed in the construction of cut-off walls in flood embankments are listed as a usefulness criteria. The article presents the potential uses of fly ash from SSTT in hardening slurry technology. It also suggests directions for further research to fully identify other potential uses of this by-product in this field.


2012 ◽  
Vol 209-211 ◽  
pp. 1245-1252
Author(s):  
Zheng Zhong Zeng ◽  
Xiao Li Wang ◽  
Yu Pan ◽  
Zhong Ren Nan

The land use has become the international mainstream and the favorable direction to dispose the municipal sewage sludge in recent years. The heavy metals, however, are the major barrier that limit the land utilization. Batch aerobic composting experiments were conducted to investigate the effect of composting and co-composting with fly ash on the shape of the heavy metals (Ni & Cd) in sludge by using the sawdust to regulate the C/N ratio. Results have shown that co-composting with fly ash can significantly change Ni & Cd species distribution, leading unstable state content of Ni lower than composting only. However, the result is not as good as composting only in terms of Cd. At the same time the fly ash dosage equaling 14% of the dry sludge mass was the optimized quantity to guarantee the lowest exchangeable fraction amount of the two heavy metals.


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