Valorization of Sewage Sludge via Gasification and Transportation of Compressed Syngas

A significant challenge in the utilization of alternative gaseous fuels is to use their energy potential at the desired location, considering economic feasibility and sustainability. A potential solution is a compression, transportation in pressure tanks, and generation of electricity and heat directly at the recipient. In this research, the potential for generating syngas from abundant waste substrates was analyzed. The sewage sludge (SS) was used as an example of a bulky and abundant resource that could be valorized via gasification, compression, and transport to end-users in containers. A model was developed, and theoretical analyses were completed to examine the influence of the calorific value of the syngas produced from the SS gasification (under different temperatures and gasifying agents) on the efficiency of energy transportation of compressed syngas. First, the gasification simulation was carried out, assuming equilibrium in a downdraft gasifier (reactor) from 973–1473 K and five gasifying agents (O2, H2, CO2, water vapor, and air). Molar ratios of the gasifying agents to the (SS) C ranged from 0.1–1.0. The model predicted syngas composition, lower calorific values (LHV) for a given molar ratio of the gasification agent, and compressibility factor. It was shown that the highest LHV was obtained at 0.1 molar ratio for all gasifier agents. The highest LHV (~20 MJ∙(Nm3)−1) was obtained by gasification with H2 and the lowest (~13 MJ∙(Nm3)−1) in the case of air. Next, the available syngas volume in a compressed gas transportation unit and the stored energy was estimated. The largest syngas volume can be transported when O2 is used as a gasifying agent, but the highest amount of transported energy was estimated for gasification with H2. Finally, the techno-economic analyses showed that syngas from SS could be competitive when the energy of compressed syngas is compared with the demand of an average residential dwelling. The developed syngas energy transport system (SETS) concept proposes a new method to distribute compressed syngas in pressure tanks to end-users using all modes of transport carrying intermodal ISO containers. Future work should include the determination of energy demand for syngas compression, including pressure losses, heat losses, and analysis of the influence of syngas on storage and compression devices.

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The Bioconversion of Sewage Sludge to Bio-Fuel: The Environmental and Economic Benefits

Materials ◽

10.3390/ma12152417 ◽

2019 ◽

Vol 12 (15) ◽

pp. 2417 ◽

Cited By ~ 3

Author(s):

Adam Smoliński ◽

Janusz Karwot ◽

Jan Bondaruk ◽

Andrzej Bąk

Keyword(s):

Sewage Sludge ◽

Fossil Fuels ◽

Waste Water Treatment ◽

Calorific Value ◽

Dry Mass ◽

Economic Benefits ◽

Economic Feasibility ◽

Hard Coal ◽

Energy Potential ◽

Industrial Energy

This paper aims to analyze the economic feasibility of generating a novel, innovative biofuel—bioenergy—obtained from deposit bio-components by means of a pilot installation of sewage sludge bio-conversion. Fuel produced from sewage sludge biomass bears the potential of being considered a renewable energy source. In the present study, 23 bioconversion cycles were conducted taking into consideration the different contents, types of high carbohydrate additives, moisture content of the mixture as well as the shape of the bed elements. The biofuel was produced using post fermentation sewage sludge for industrial energy and heat generation. Based on the presented research it was concluded that the composite biofuel can be co-combusted with hard coal with the optimal percentage share within the range of 20–30% w/w. Sewage sludge stabilized by means of anaerobic digestion carried out in closed fermentation chambers is the final product. The average values of the CO2, CO, NO, NOx and SO2 concentrations in flue gas from co-combustion of a bioconversion product (20% w/w) and coal were 5.43%, 1903 ppm, 300 ppm, 303 ppm and 179 ppm, respectively. In total, within a period of 4.5 years of the plant operation, 1853 Mg of fuel was produced and successfully co-combusted with coal in a power plant. The research demonstrated that in the waste water treatment sector there exists energy potential in terms of calorific value which translates into tangible benefits both in the context of energy generation as well as environmental protection. Over 700,000 Mg of bio-sewage sludge is generated annually in Poland. According to findings of the study presented in the paper, the proposed solution could give 970,000 Mg of dry mass of biomass qualified as energy biomass replacing fossil fuels.

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THE GENERAL PRINCIPLES OF WASTE PROCESSING WITH RECOVERY OF THEIR ENERGY POTENTIAL ON THE BASIS OF PLASMA TECHNOLOGIES. PART III. COMPARATIVE ANALYSIS OF THE OXYGEN AND AIR BLOWING INFLUENCE AND THE ROLE OF CALORIFIC CONTENT OF SEWAGE SLUDGE

Energy Technologies & Resource Saving ◽

10.33070/etars.2.2018.03 ◽

2018 ◽

pp. 16-30

Author(s):

V.A. Zhovtyansky ◽

E.P. Kolesnikova ◽

M.V. Yakymovych ◽

P.A. Seredenko

Keyword(s):

Sewage Sludge ◽

Calorific Value ◽

Waste Processing ◽

Energy Potential ◽

Gasification Process ◽

Calorific Content ◽

Air Blowing ◽

The Enthalpy Of Formation ◽

Plasma Technologies

The issues of determination calorific value as well as the enthalpy of formation of sewage sludge are deeply analyzed further to previous publications. Taking into account this analysis, the indicators, the indicators of the efficiency of the sewage sludge gasification process have been clarified and a comparison of the plasma-steam-oxygen and plasmasteamair gasification technologies has been made. At the same time, on the basis of previous studies, the influence on the efficiency indices of not only ballast nitrogen, but also nitrogen oxides is analyzed. Their concentrations cannot be determined on the basis of simple thermodynamic ratios. Bibl 38, Fig. 6, Tab. 1.

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Municipal Solid Waste Characteristic and Energy Potential in Piyungan Landfill

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.898.58 ◽

2020 ◽

Vol 898 ◽

pp. 58-63

Author(s):

Adolf Leopold S.M. Sihombing ◽

Ragil Darmawan

Keyword(s):

Anaerobic Digestion ◽

Potential Energy ◽

Landfill Gas ◽

Calorific Value ◽

Economic Feasibility ◽

International Standards ◽

Raw Material ◽

Energy Potential ◽

The Right ◽

Gasification Technology

The daily waste tonnage at Piyungan landfill is 600 tons consisting of organic and combustible waste which can be used as an energy source. The aim of this study is to determine the potential energy of waste in the Piyungan landfill by its characteristics based on technology options including landfill gas, anaerobic digestion, gasification, and incineration. The Piyungan landfill mostly contain organic waste, up to 62.1% and combustible waste (RDF) at 26.8%. Moisture content of Piyungan’s RDF is higher than international standards for RDF as raw material in several countries. The various result for Nett Calorific Value is about 7.27 MJ/kg for fresh waste, 12.78 MJ/kg for RDF, 1.74 MJ/kg for market waste and 4.14 MJ/kg for mining waste. Landfill gas can generate energy up to 1.2 MW at the beginning and reaches 2 MW during peak periods. The potential energy by using anaerobic digestion and gasification technology are 1.54 MW and 3.12 MW. By incinerate fresh waste, the potential energy can be generated up to 9 MW and 4.39 MW when incinerate RDF waste only. Calculation of potential energy can be used as a basis for selecting the right technology, especially for economic feasibility for each technology.

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Urban energy system management for enhanced energy potential for upcoming smart cities

Energy Exploration & Exploitation ◽

10.1177/0144598720937529 ◽

2020 ◽

Vol 38 (5) ◽

pp. 1968-1982

Author(s):

Deepak Kumar

Keyword(s):

Renewable Energy ◽

Energy Demand ◽

Industrial Development ◽

Smart Cities ◽

Energy System ◽

Economic Feasibility ◽

Urban Region ◽

Design Development ◽

Energy Potential ◽

Hybrid Renewable Energy System

Scientific and industrial development has given rise to a rapidly increasing energy demand. Alternative and augmented energy resources are expected everywhere due to scarcity and depletion of other non-renewable resources. During recent years wind and solar had emerged as a promising cleaner energy source to offer a favourable solution with better efficiency. Hence, the attention has now diverted towards scaling up of hybrid system of energy generation. Numerous attempts have been taken to demonstrate the technological development concerning the requirement of the region. Whilst some research has already started to evaluate the working of the prototype, insignificant attention has been paid towards it. The current work also focuses on the simulation with hybrid urban renewable energy systems for techno-economic feasibility analysis. There were earlier attempts to report the advancement occurred in the technological, scientific and industrial sector due to hybrid renewable energy system. In some regard, it was an attempt to showcase the modelling of a typical urban requirement in an hourly load profile to identify in the energy potentials of the urban region. These will help to summarize the past, present and future trends of the hybrid energy system design, development and implementation for the urban region, which can be later on replicated to other parts of the world.

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The Enhancement of Energy Efficiency in a Wastewater Treatment Plant through Sustainable Biogas Use: Case Study from Poland

Energies ◽

10.3390/en13226056 ◽

2020 ◽

Vol 13 (22) ◽

pp. 6056 ◽

Cited By ~ 2

Author(s):

Adam Masłoń ◽

Joanna Czarnota ◽

Aleksandra Szaja ◽

Joanna Szulżyk-Cieplak ◽

Grzegorz Łagód

Keyword(s):

Energy Efficiency ◽

Wastewater Treatment ◽

Energy Balance ◽

Sewage Sludge ◽

Energy Demand ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

High Energy ◽

Energy Potential ◽

Process Implementation

The improvement of energy efficiency ensuring high nutrients removal is a great concern for many wastewater treatment plants (WWTPs). The energy balance of a WWTP can be improved through the application of highly efficient digestion or its intensification, e.g., through the introduction of the co-substrates with relatively high energy potential to the sewage sludge (SS). In the present study, the overview of the energetic aspect of the Polish WWTPs was presented. The evaluation of energy consumption at individual stages of wastewater treatment along with the possibilities of its increasing was performed. Additionally, the influence of co-digestion process implementation on the energy efficiency of a selected WWTP in Poland was investigated. The evaluation was carried out for a WWTP located in Iława. Both energetic and treatment efficiency were analyzed. The energy balance evaluation of this WWTP was also performed. The obtained results indicated that the WWTP in Iława produced on average 2.54 GWh per year (7.63 GWh of electricity in total) as a result of the co-digestion of sewage sludge with poultry processing waste. A single cubic meter of co-substrates fed to the digesters yielded an average of 25.6 ± 4.3 Nm3 of biogas (between 18.3 and 32.2 Nm3/m3). This enabled covering the energy demand of the plant to a very high degree, ranging from 93.0% to 99.8% (98.2% on average). Importantly, in the presence of the co-substrate, the removal efficiency of organic compounds was enhanced from 64% (mono-digestion) to 69–70%.

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Waste-to-Carbon: Is the Torrefied Sewage Sludge with High Ash Content a Better Fuel or Fertilizer?

Materials ◽

10.3390/ma13040954 ◽

2020 ◽

Vol 13 (4) ◽

pp. 954 ◽

Cited By ~ 2

Author(s):

Jakub Pulka ◽

Piotr Manczarski ◽

Paweł Stępień ◽

Marzena Styczyńska ◽

Jacek A. Koziel ◽

...

Keyword(s):

Sewage Sludge ◽

Energy Demand ◽

Organic Fertilizer ◽

Waste Recycling ◽

Ash Content ◽

Biogenic Element ◽

Molar Ratio ◽

Biogenic Elements ◽

Low Temperature Pyrolysis ◽

First Time

Sewage sludge (SS) recycling is an important part of the proposed ‘circular economy’ concept. SS can be valorized via torrefaction (also known as ‘low-temperature pyrolysis’ or ‘roasting’). SS can, therefore, be considered a low-quality fuel or a source of nutrients essential for plant growth. Biochar produced by torrefaction of SS is a form of carbonized fuel or fertilizer. In this research, for the first time, we tested the feasibility of torrefaction of SS with high ash content for either fuel or organic fertilizer production. The research was conducted in 18 variants (six torrefaction temperatures between 200~300 °C, and three process residence times of 20, 40, 60 min) in 5 repetitions. Fuel and fertilizer properties and multiple regression analysis of produced biochar were conducted. The higher heating value (HHV) of raw SS was 21.2 MJ·kg−1. Produced biochar was characterized by HHV up to 12.85 MJ·kg−1 and lower H/C and O/C molar ratio. Therefore, torrefaction of SS with high ash content should not be considered as a method for improving the fuel properties. Instead, the production of fertilizer appears to be favorable. The torrefaction increased C, N, Mg, Ca, K, Na concentration in relation to raw SS. No significant (p < 0.05) influence of the increase of temperature and residence time on the increase of biogenic elements in biochar was found, however the highest biogenic element content, were found in biochar produced for 60 min, under the temperature ranging from 200 to 240 °C. Obtained biochars met the Polish regulatory criteria for mineral-organic fertilizer. Therefore SS torrefaction may be considered a feasible waste recycling technology. The calculation of torrefaction energy and the mass balance shows energy demand <2.5 GJ∙Mg−1 w.m., and the expected mass yield of the product, organic fertilizer, is ~178 kg∙Mg−1 w.m of SS. Further investigation should consider the scaling-up of the SS torrefaction process, with the application of other types of SSs.

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Municipal Solid Waste Management and Waste-to-Energy Potential from Rajshahi City Corporation in Bangladesh

Applied Sciences ◽

10.3390/app11093744 ◽

2021 ◽

Vol 11 (9) ◽

pp. 3744

Author(s):

Md. Ahasan Habib ◽

Mim Mashrur Ahmed ◽

Muhammad Aziz ◽

Mohd. Rafiqul Alam Beg ◽

Md. Emdadul Hoque

Keyword(s):

Waste Management ◽

Human Health ◽

Energy Demand ◽

Large Scale ◽

Solid Waste Management ◽

Calorific Value ◽

Waste To Energy ◽

Municipal Solid Waste Management ◽

Energy Potential ◽

Rajshahi City

Waste management is becoming one of the most challenging tasks for developing countries in order to ensure good human health, as well as a healthy environment. Rajshahi City Corporation (RCC) is one of the 12 city corporations in Bangladesh. Various environmental and human health problems have arisen due to a lack of proper knowledge of waste management. Thus, the aim of this work is to illustrate the present status of MSW generation and management in Rajshahi City Corporation, Bangladesh. Fifty households were selected throughout RCC for waste collection, which represent approximately all types of households in RCC. From the qualitative and quantitative analysis, it is estimated that the approximate MSW generation in RCC is 358.19 t/d (tons/day) at an approximate rate of 0.4214 kg/person/d. Calorific values of the wastes have also been determined using the ultimate analysis results of the MSW. A higher calorific value of the dry MSW has been calculated as 14.9 MJ/kg. Moisture content of the MSW has been found to be 48.28%. It is also estimated that the possible power generation (steam energy to electrical power) from MSW generated in RCC is 159.40 MWh/d. Lastly, future scopes of MSW management and different waste management measures that need to be taken are illustrated. Waste-to-energy (WTE) conversion has been given priority and anaerobic digestion (AD) has been found to be an interesting prospect in this sector. Techno-economic analysis of the AD has been conducted. Energy potential from the proposed plant has been calculated as 3.85 MW and the payback period has been found to be 4.9 years. It has been observed that employing AD on a large scale can not only reduce the waste, but also meet a large portion of the energy demand of this city.

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Technical and economic feasibility study of a solar plant on a commercial surface in Azogues, Ecuador

Renewable Energy and Power Quality Journal ◽

10.24084/repqj19.250 ◽

2021 ◽

Vol 19 ◽

pp. 177-183

Author(s):

I. Bermeo ◽

◽

L. Matute ◽

E. Barragán-Escandón ◽

X. Serrano-Guerrero ◽

...

Keyword(s):

Energy Demand ◽

Demand Curve ◽

Energy Requirement ◽

Evaluation Process ◽

Economic Feasibility ◽

International Standards ◽

Photovoltaic System ◽

Shopping Mall ◽

Energy Potential ◽

Solar Plant

The submitted paper deals with the shopping mall project that will be supplied with solar power. The selected location was "La Playa Store" shopping center located in the city of Azogues, south of Ecuador. This type of building has at least two characteristics worth studying i) the available surface on the roof, ii) the characteristics of the energy demand curve. This evaluation process establishes the energy requirement of the installation; that is, the energy potential available depending on the surface of its roof, to design a solar plant according to international standards and local ARCONEL 003/18 regulations. The tools used for the involving simulation were the Lumion software, an IFC file created and imported into the Solarius Pv energy simulator, a software specialized in the design of photovoltaic systems. The designed photovoltaic system has a projected annual energy generation of 9,3695.26 kWh; an installed price per watt of $1.1 with viable results at the end of the fifth year of implementation with an IRR of 7.33% and NPV of $390.51. As this is a commercial facility, a constant and flat consumption throughout the day is expected, so implementing solar energy would reduce the actual power requirements by 32.63%

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Production of fuels on the basis of sewage sludge through conditioning using high calorific value fractions

Water Practice & Technology ◽

10.2166/wpt.2008.011 ◽

2008 ◽

Vol 3 (1) ◽

Author(s):

Karl-Georg Schmelz ◽

Anja Reipa ◽

Hartmut Meyer

Keyword(s):

Sewage Sludge ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Calorific Value ◽

Fluidised Bed ◽

Sludge Treatment ◽

Heating Value ◽

Fine Coal ◽

Used Cars ◽

Plastic Components

Emschergenossenschaft and Lippeverband operate 59 wastewater treatment plants which produce approx. 100,000 Mg TS of sewage sludge each year. Using sludge pressure pipelines, about 60 % of this sludge are transported to the central sludge treatment plant in Bottrop. The digested sludges are conditioned using fine coal and polymers and are dewatered using membrane filters. By adding coal, the heating value of the sludge is raised which enables autothermal combustion of the dewatered sludges in fluidised bed furnaces at the central sludge treatment plant. In order to replace coal, a fossil fuel, as conditioning agent, experiments were conducted using alternative materials with high heating values. The addition of shredder fluff agglomerates proved to be particularly successful. Shredder fluff agglomerates are a residue from the recycling of used cars and are generated in a multistage process (e.g. Volkswagen-SiCon Process) by separating the light shredder fraction (plastic components etc.) from the total shredder fluff. The fibrous material is outstandingly suitable for improving the dewaterability and for sufficiently raising the heating value of the dewatered sludge in order to enable autothermal combustion. Since first experiments showed very positive results, a full-scale long-term test-run will take place in 2007.

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Sewage Sludge Treatment by Hydrothermal Carbonization: Feasibility Study for Sustainable Nutrient Recovery and Fuel Production

Energies ◽

10.3390/en14092697 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2697

Author(s):

Gabriel Gerner ◽

Luca Meyer ◽

Rahel Wanner ◽

Thomas Keller ◽

Rolf Krebs

Keyword(s):

Liquid Phase ◽

Sewage Sludge ◽

Hydrothermal Carbonization ◽

Economic Feasibility ◽

Phosphorus Recovery ◽

High Yield ◽

Nutrient Recovery ◽

Waste Biomass ◽

Sludge Treatment ◽

Sewage Sludge Treatment

Phosphorus recovery from waste biomass is becoming increasingly important, given that phosphorus is an exhaustible non-renewable resource. For the recovery of plant nutrients and production of climate-neutral fuel from wet waste streams, hydrothermal carbonization (HTC) has been suggested as a promising technology. In this study, digested sewage sludge (DSS) was used as waste material for phosphorus and nitrogen recovery. HTC was conducted at 200 °C for 4 h, followed by phosphorus stripping (PS) or leaching (PL) at room temperature. The results showed that for PS and PL around 84% and 71% of phosphorus, as well as 53% and 54% of nitrogen, respectively, could be recovered in the liquid phase (process water and/or extract). Heavy metals were mainly transferred to the hydrochar and only <1 ppm of Cd and 21–43 ppm of Zn were found to be in the liquid phase of the acid treatments. According to the economic feasibility calculation, the HTC-treatment per dry ton DSS with an industrial-scale plant would cost around 608 USD. Between 349–406 kg of sulfuric acid are required per dry ton DSS to achieve a high yield in phosphorus recovery, which causes additional costs of 96–118 USD. Compared to current sewage sludge treatment costs in Switzerland, which range between 669 USD and 1173 USD, HTC can be an economically feasible process for DSS treatment and nutrient recovery.

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