Pyrolysis Plant Research Articles

Pyrolysis of plastic waste for production of heavy fuel substitute: A techno-economic assessment

Pyrolysis is widely seen as a promising technology for converting plastic waste into a wax/oil product which can be used as a heavy fuel oil substitute or as raw material by the petrochemical industry. A pyrolysis plant with a capacity of 100 kg/h plastic waste is modelled in the process simulation software Aspen HYSYS. The production costs of the pyrolysis fuel product is estimated at £0.87/kg which is 58% higher than current market prices; therefore, a scaling-up analysis is also carried out to determine the plant capacity for which the pyrolysis process is economically feasible. The fuel production costs of the scaled-up cases considered are approximately 2.2–20.8 times lower than the existing market prices of residual fuel oil, indicating their economic feasibility. For the 1000 kg/h and 10,000 kg/h plant capacity cases the facility needs to operate approximately four years and one year respectively, to recover the capital investment, while the 100,000 kg/h case produces revenue and has a positive NPV within year one. A sensitivity analysis is also carried out revealing that the fuel production rate is the most sensitive parameter for the 100 kg/h plant, as well as the scaled-up plants.

Mobile Autothermal Pyrolysis System for Local Biomass Conversion: Process Simulation and Techno-Economic Analysis

This paper presents a mobile autothermal pyrolysis system for locally converting biomass feedstock into bio-oil that can be transported easily. The system includes a compact internally interconnected fluidized bed (IIFB) reactor, a biomass pretreatment facility, and a product recovery unit. On the basis of modified chemical kinetic models, the pyrolysis process of common forestry and agricultural residues in this mobile system has been simulated. The pyrolytic product distribution from simulation has good agreements with experimental results. Then, the techno-economic performance of the mobile pyrolysis system in China is evaluated and compared with other liquid biofuel production facilities, i.e., fixed biomass pyrolysis plants and Fischer–Tropsch liquids production via biomass gasification (BG-FT). The results indicate that the biomass feedstock cost of mobile pyrolysis systems can be effectively reduced. Compared with the fixed biofuel production plant, the labor cost is higher for the mobile plant. Th...

Development of secondary chamber for tar cracking–improvement of wood pyrolysis performance in pre-vacuum chamber

Energy crisis and global warming, in other words, climate change are critical topics discussed in various parts of the world. Global warming primarily result from too much emission of carbon dioxide (CO2) in the atmosphere. To mitigate global warming, or climate change and improve electrification in rural areas, wood pyrolysis technology is developed in a laboratory scale, of which gases are directly applicable to the gas engine generator. Our laboratory has developed a prototype of wood pyrolysis plant with a pre-vacuum chamber. However, tar yield was around 40 wt% of feedstock. This research aims to reduce tar yield by secondary tar cracking. For the secondary tar cracking, a secondary pre-vacuum chamber is installed after primary pre-vacuum chamber. Gases generated in the primary pre-vacuum chamber are lead into the secondary chamber that is heated up to 1000 K. This paper reports performance of the secondary chamber for secondary tar cracking in homogeneous mode and heterogeneous mode with char.

Energetic Viability of a Polyolefin Pyrolysis Plant

The energetic viability of a polyolefin pyrolysis unit that could be installed in a refinery plant was examined. Thermal pyrolysis at 500 and 700 °C, and the catalytic cracking by means of HZSM-5 and HY catalysts were analyzed. The energy requirements for an initial separation of the products by means of distillation towers into four main lumps (gas, gasoline fraction, diesel fraction, and waxes) that could be directly treated in a refinery were calculated as well. An energy balance closure and a sensitivity analysis were also carried out for all cases in order to check the accuracy of the yields of products previously obtained. These results were highly satisfactory for all cases, although the actual heat of combustion might be slightly higher than the values measured experimentally (around 5%). The results of the energetic viability analysis showed that only about 5% of the input mass flow rate is needed to burn to satisfy the energy requirements of the plant. Thus, the heat released in the combustion of the product fraction stream that is in minor proportion in each case proved to be sufficient.

Partial deoxygenation of biomass derived pyrolysis liquids

Biomass pyrolysis liquids (also known as bio-oil), are derived from renewable lignocellulosic biomass residues by fast pyrolysis process. These second-generation oxygenated hydrocarbon resources have the potential to partially substitute for petroleum-derived feedstocks and thus enhance the economic and environmental sustainability of our natural resources. However, in contrast to petroleum fuels, biomass-derived pyrolysis liquids contain a large amount of oxygen, usually 40-50% wt% (wet basis). This undesirable high oxygen content in pyrolysis liquids is considered as the primary reason for its high polarity, high acidity, lower stability, lower energy density and very low miscibility with conventional crude refining feedstocks. There are two major pathways for upgrading the pyrolysis liquids. While hydrodeoxygenation route is one of the most explored options, it requires production and supply of large amounts of expensive hydrogen at high pressures, mandating large and centralized upgrading plants, and thus large capital investment. In this paper, we discuss an alternative method of pyrolysis liquid upgrading, using cheap and affordable hydrogen donor additives and catalysts to promote partial deoxygenation at near atmospheric pressure. This approach is preferably to be used as a pre-treatment and stabilizing method for pyrolysis liquids in the close vicinity of remote biomass pyrolysis plants. The pre-treated oil, then can be shipped for further hydrocracking process in a centralized co-processing facility. Preliminary results from the initial proof of concept experiments involving a 200 g/h gas-phase continuous fast catalytic cracking system with continuous coke removal to enhance deoxygenation performance are presented. These results indicate positive impact of catalyst bed on quality and yield of the upgraded bio-oil product in terms of pH, viscosity, degree of deoxygenation, oil yield and concentration of hydrogen in the off gases.

Utilization of eucalyptus for electricity production in Brazil via fast pyrolysis: A techno-economic analysis

Abstract A process model of a 2000 metric ton per day eucalyptus Tail Gas Reactive Pyrolysis (TGRP) and electricity generation plant was developed and simulated in Pro/II software for the purpose of evaluating its techno-economic viability in Brazil. Two scenarios were compared based on operational conditions in the country: a single biomass to bio-oil TGRP production facility and a distributed/satellite processing that consists of several small TGRP production facilities with aggregate capacity similar to the single one, both feeding into one centralized electricity generation plant. The selling price at the breakeven point of the electricity generated via TGRP was estimated to be US$0.34 and US$0.62 per kWh for the single and the distributed scenarios respectively, considering a 10-year payback period. The single capacity pyrolysis and electricity generation facility is found to have better economic benefits over the distributed plants of small sizes under the current conditions in Brazil. The results therefore indicate that pyrolysis of eucalyptus wood for electricity in a single facility cannot be competitive with the current electricity cost in Brazil (US$0.08–0.13/kWh) at present time. Considering auxiliary benefits such as climate change and carbon credits, plus the continuous increasing in the electricity market price in Brazil, both scenarios could be competitive in the future.

Bio-oil production from fast pyrolysis of rice husk in a commercial-scale plant with a downdraft circulating fluidized bed reactor

Bio-oil, a promising candidate to replace fossil fuels, has received considerable attention for its sustainability, resource diversity and environmental benefits. Industrial production of bio-oil is urgently needed. In this study, a downdraft circulating fluidized bed reactor commercial-scale fast pyrolysis plant with biomass throughput of 1–3th−1 is studied. Rice husk was processed at a fast pyrolysis temperature of 550°C to evaluate the plant operation status. The system was continuously operated for 80.42h. The thermal properties of the feedstock (rice husk), dust (separated from feedstock), char and heat carrier were analyzed and the bio-oil properties such as water content, pyrolytic water content, viscosity, density, pH, heating value, solid content and ash content were analyzed and presented. All the tested properties of the bio-oil meets the pyrolysis liquid biofuels standards in ASTM D7544-12 for Grade G biofuels, except for the water content of the bio-oil, which is slightly higher than that of Grade G biofuels. In energy balance analysis, the potential recovered energy of the three main products was 8.0±1.1, 2.1±0.1 and 5.3±0.7MJkg−1 for bio-oil, char and non-condensable gas, respectively, which shows that the largest portion of the energy in biomass was recovered in the bio-oil.

Process Integration of a Polygeneration Plant with Biomass/Coal Co-pyrolysis

The concept of co-pyrolysis of biomass and conventional fossil fuel offers various advantages such as higher liquid product yield and higher char conversion than if the coal and biomass particles were processed individually. In the case of added value fuel production such as diesel and gasoline, the maximization of the fraction of pyrolysis oil is the foremost objective. At the same time, the produced char and permanent gases should be properly used for the isothermal and stable operation of the pyrolysis process. This study presents an integrated model of co-pyrolysis in ASPEN Plus for the production of advanced hydrocarbons aiming to determine the conditions under which the process performance is maximized. The methodology for the design and modeling of each main unit of the system (i.e., the pyrolysis plant, the oil upgrading unit, and char exploitation plant) is described in detail. Simulation runs were performed for various blending ratios from 0% to 100% of coal to biomass, aiming for the optimum de...

Experimental investigations on a diesel engine operated with fuel blends derived from a mixture of Pakistani waste tyre oil and waste soybean oil biodiesel.

The waste tyre and waste cooking oils have a great potential to be used as alternative fuels for diesel engines. The aim of this study was to convert light fractions of pyrolysis oil derived from Pakistani waste vehicle tyres and waste soybean oil methyl esters into valuable fuel and to reduce waste disposal-associated environmental problems. In this study, the waste tyre pyrolysis liquid (light fraction) was collected from commercial tyre pyrolysis plant and biodiesel was prepared from waste soybean oil. The fuel blends (FMWO10, FMWO20, FMWO30, FMWO40 and FMWO50) were prepared from a 30:70 mixture of waste tyre pyrolysis liquid and waste soybean oil methyl esters with different proportions of mineral diesel. The mixture was named as the fuel mixture of waste oils (FMWO). FT-IR analysis of the fuel mixture was carried out using ALPHA FT-IR spectrometer. Experimental investigations on a diesel engine were carried out with various FMWO blends. It was observed that the engine fuel consumption was marginally increased and brake thermal efficiency was marginally decreased with FMWO fuel blends. FMWO10 has shown lowest NOx emissions among all the fuel blends tested. In addition, HC, CO and smoke emissions were noticeably decreased by 3.1-15.6%, 16.5-33.2%, and 1.8-4.5%, respectively, in comparison to diesel fuel, thereby qualifying the blends to be used as alternative fuel for diesel engines.

Reduced Local Emissions and Long-term Carbon Storage through Pyrolysis of Agricultural Waste and Application of Pyrolysis Char for Soil Improvement

The direct storage of biologically stable pyrolysis char in soils is discussed as a low-tech below zero emission technology option with positive side-effects. A rotary kiln pyrolysis process, which has already been successfully applied at industrial scale before, is selected as the reference technology. Cotton stalks are considered as feed for the pyrolysis plant, representing a typical agricultural by-product with short rotation times. The plant efficiency is calculated for the case that the thermal energy that runs the pyrolysis process is provided by combustion of a part of the pyrolysis gas, while pyrolysis oil is provided as a product. The remaining pyrolysis gas powers a gas engine-based combined heat and power (CHP) island. 100% of fuel power fed with the biomass are distributed as follows (based on the lower heating value): 52% stay in the biochar, 13% in the pyrolysis oil, 10% are converted to electric power in the CHP plant, and, finally 15% are available as heat at a temperature span between forward and back flow of 100°C/70°C and may be used on-site for drying of agricultural products and pyrolysis feedstock. A rough comparison of the proposed process to biomass power generation substituting coal-fired power generation shows that the net effects on the carbon balance are comparable, but additional carbon-neutral energy streams are generated in the pyrolysis case.

Obtención de modelo dinámico del proceso de pirólisis de polímeros utilizando datos de una termogravimetría

Este documento describe un procedimiento sistemático para obtener un modelo dinámico alternativo de la degradación térmica de polietileno de baja densidad (LDPE por sus siglas en inglés) a partir de los datos experimentales del análisis termogravimétrico. El modelo dinámico del proceso está dado por un par de ecuaciones diferenciales de primer orden propuestas por primera vez en éste trabajo. Se expone el procedimiento para deducir los parámetros de la ecuación que describe la degradación térmica a partir de los datos experimentales de una termogravimetría. Se ejecuta una simulación básica para evaluar el comportamiento del proceso de pirólisis del polímero considerado ante la aplicación de una potencia térmica constante, registrando las variables de temperatura y masa residual. Este trabajo constituye la primera etapa de un proyecto de investigación que tiene como objetivo principal, la puesta en funcionamiento de un sistema de control para regular la operación de una planta de pirólisis de residuos plásticos urbanos a escala de laboratorio.

Study of Physicochemical Properties of Heavy Pyrolysis Tar for its Utilization as Feedstock for Producing Petroleum Pitch

The results of study of composition and physicochemical properties of ethylene production byproduct, namely, heavy pyrolysis tar (HPT) are reported. It is shown that HPT is a complex multicomponent mixture essentially of aromatic compounds and partially of unsaturated hydrocarbons. The composition and physicochemical properties of HPT in an industrial pyrolysis plant vary with time in a wide range even when the same type of feedstock is pyrolyzed. In view of this, for using HPT as a feedstock for producing carbon material of a fixed quality, it is necessary to stabilize its composition, structure, and properties over time. The potential paths of solving this problem, among which are production of HPT as one of the target pyrolysis products and preparation of HPT as an olefin production by-product for processing into carbon materials of a fixed quality, are discussed.

Analysis of tar compounds and quantification of naphthalene from thermal treatment of household biowaste

Household biowaste represent the organic fraction of municipal solid waste and are an underutilized resource. Although previous studies have performed pyrolysis of organic waste, the vast majority has been on specific presorted feedstock or conventional lignocellulosic streams. Therefore, there is a lack of pyrolysis applications on representative food waste as retrieved from households and this can be attributed primarily to their high water content and their degradability. But via the intermediate step of drying, long-term storage and thermal treatment have become possible. In the framework of this study, household biowaste were pyrolyzed for the production of carbonaceous materials with a main focus on the analysis of produced tar compounds. Tars can be corrosive or cause clogging and disrupt the operation of pyrolysis and gasification plants. Their analysis has faced several difficulties due to inconsistency in the methodologies that have been applied by various groups. The tar protocol has provided a solid framework for consistent analysis of tars but until now has been solely used for the case of gasification. This study aimed to apply the tar protocol for pyrolysis and to enhance the detectability of the method for a wider range of tars by means of elemental analysis, attenuated total reflectance (ATR) and gas chromatography-mass spectrometry (GC-MS). GC- MS was performed by means of a specific column for PAHs identification and calibration methods were developed for the proper quantification of naphthalene which is the dominant tar compound. The results of the analysis showed that naphthalene concentration increased from torrefaction to carbonization but then decreased significantly for high temperature pyrolysis at 860 °C.

3-16.二重釜式熱分解装置により生じた熱分解残さの性質((4)熱分解I,Session 3 バイオマス等)

3-16.二重釜式熱分解装置により生じた熱分解残さの性質((4)熱分解I,Session 3 バイオマス等)

Exploring Suitable Utilization of Waste Tires in Chiang Mai

The study aims at utilizing waste tires in Chiang Mai municipal area. As there are approximately 27,000 waste tires per month, by which each contains up to 37 MJ/kg, there must be a better way than dumping. Therefore, the study explores the feasibilities of utilizing these waste tires by establishing (i) a rubber crumbing factory, (ii) a pyrolysis plant and (iii) a rubber power plant. Here, the site is firstly selected based on available supply, using basic optimization models. Then, the study focuses on the feasibility of demand, engineering, finance and social/ environment response of the three options. Finally, analytic hierarchy process is used to reflect the suitability of the options based on factors of interest. Within the options considered, a pyrolysis plant appears to be the most attractive.

Techno-economic analysis of biofuel production via bio-oil zeolite upgrading: An evaluation of two catalyst regeneration systems

Biofuels have been identified as a mid-term greenhouse gas (GHG) emissions abatement solution for decarbonising the transport sector. This study examines the techno-economic analysis of biofuel production via biomass fast pyrolysis and subsequent bio-oil upgrading via zeolite cracking. The aim of this study is to compare the techno-economic feasibility of two conceptual catalyst regeneration configurations for the zeolite cracking process: (i) a two-stage regenerator operating sequentially in partial and complete combustion modes (P-2RG) and (ii) a single stage regenerator operating in complete combustion mode coupled with a catalyst cooler (P-1RGC). The designs were implemented in Aspen Plus® based on a hypothetical 72 t/day pine wood fast pyrolysis and zeolite cracking plant and compared in terms of energy efficiency and profitability. The energy efficiencies of P-2RG and P-1RGC were estimated at 54% and 52%, respectively with corresponding minimum fuel selling prices (MFSPs) of £7.48/GGE and £7.20/GGE. Sensitivity analysis revealed that the MFSPs of both designs are mainly sensitive to variations in fuel yield, operating cost and income tax. Furthermore, uncertainty analysis indicated that the likely range of the MFSPs of P-1RGC (£5.81/GGE − £11.63/GGE) at 95% probability was more economically favourable compared with P-2RG, along with a penalty of 2% reduction in energy efficiency. The results provide evidence to support the economic viability of biofuel production via zeolite cracking of pyrolysis-derived bio-oil.

Effects of Secondary Chamber on Gas Yield by Pre-Vacuum Chamber Pyrolysis of Rubber Wood

Global warming awareness criticizes further usage of fossil fuels and insists promotion of renewable energy usage. Additionally, many people in rural areas of developing countries cannot access electricity. To solve this sort of energy crisis including global warming, current authors developed a proto-type of a pyrolysis plant equipped with a prevacuum chamber, which can be used to produce combustible gases for an engine generator in rural areas where people cannot access electricity. The plant is simple and easily maintained in consideration of special conditions that a rural area can receive very few maintenance service, technical assistance, and supply of spare parts. However, gas yield obtained by the proto-type of plant was around 20 wt% of feedstock. One way to enhance gas yield from this proto-type of plant is to utilize reaction of secondary tar cracking. This research work aims to examine possibility of gas yield enhancement keeping a simple structure of the proto-type of plant and using a simple technique of secondary tar cracking. Two tar cracking methods are examined: one is homogeneous tar cracking and the other is heterogeneous tar cracking using catalysis. In the homogeneous tar cracking, pyrolysis gases must be heated up to 650oC to 700oC and in the heterogeneous tar cracking, wood char is used as catalysis, because wood char is byproduct of pyrolysis. It is concluded that the homogeneous tar cracking is quite unlikely in the secondary chamber, but on the other hand, heterogeneous tar cracking using wood char can produce 30 wt% of gas yield from 1 kg of feedstock.

Study of the characteristics of compression of a batch of whole waste tires in a pyrolysis reactor

The publication studies the characteristics of compression of a batch of whole waste tires. The process of their dynamic compression in a pyrolysis is modeled. Dependencies of variation of the load on the tire column are analyzed at various heating temperatures and statistical load during pyrolysis. Rheological properties of the tires are considered in three relatively isolated zones of the reactor with different physical conditions. A physical model of pyrolysis reactor has been developed, which is intended for the study of rheology of whole waste tires during their heating and compression. In prospect, this model will improve the technology of thermal recycling of waste tires and increase the reactor fill factor up to 98%. The mathematical model of dynamic compression of whole waste tires in the pyrolysis reactor can be used for practical purposes during pyrolysis plant design.

CARBIDE SYNTHESIS AS A RESULT OF TITANIUM MECHANICAL ACTIVATION IN CONJUNCTION WITH VARIOUS CARBON COMPONENTS

It was established that structure modifications of carbon, received resulting from pyrolysis plant material and ash of natural graphite are the limiting factors when implementing the mechanochemical synthesis of titanium carbide in a vibratory treatment. The shown prospects of using natural graphite and modifications of the structure amorphous carbon, made from vegetable raw materials for the synthesis of titanium carbide with a minimum sulfur content. Ill. 6. Ref. 12. Tab. 1.

ANÁLISE DA VIABILIDADE ECONÔMICA DO PROCESSO DE PIRÓLISE PARA TRATAMENTO DE RESÍDUOS SÓLIDOS URBANOS: ESTUDO DE CASO APLICADO A UMA CIDADE DE MÉDIO PORTE

Find new solutions for the treatment of municipal solid waste is a challenge of modern society. The fast pyrolysis process arises as an alternative, besides generating by-products of commercial value. The general objective of this work is to evaluate the economic viability of the pyrolysis process for treatment of municipal solid waste (MSW) applied to a medium-sized town. To meet the overall objective were determined specific objectives who understood the locational alternatives study and methods of investment analysis provided certainty, uncertainty, and risk analysis. The pyrolysis process for MSW was attractive due to high operating costs and taxes on the sale of electricity and fertilizer. The Net present value-NPV resulting cash flow is negative and there is no return on capital invested, for both the enterprise and the investor's cash flow. In this case, the research has enabled the study of vario us scenarios for economic viability of the project through sensitivity analysis. Considering the possibility of integration with more municipalities to supplement the volume of raw material, reducing the cost of transport of MSW pyrolysis plant and even th e increase in the price of electrical energy for sale, or tax exemption, the project is a cost effective alternative, while in addition to the economic benefits, the pyrolysis plant enables the Elimination of environmental liabilities generated by landfill s.