Waste Refinery Research Articles

Enhanced tire oil production through hydrothermal liquefaction using devulcanization agents

The waste refinery concept has emerged as a solution to manage waste tires and motor oil, which pose significant environmental challenges. In this study, we compared two hydrothermal liquefaction (HTL) processes. The first is a conventional method using only water as a devulcanization agent (H0 process), while the second is a novel method using a mixture of devulcanization agents (H1 process: waste engine oil, water, hydrogen peroxide, benzoyl peroxide, and potassium persulfate). We investigated the effects of temperature, residence time, and water ratio (water/tire) on the yield of these HTL processes. The highest tire crude oil yield (73.4 %) was obtained at 375°C, 7.5 water ratio, and 40 min residence time, in the H1 process. These findings suggest a promising approach for more efficient and environmentally friendly waste tire recycling. Comparison between H0 and H1 yields demonstrated significant improvements with the implementation of devulcanization agents. The H1 process reduced the optimum process temperature by 47°C, increased tire crude oil yield by 41 %, reduced tire char yield by 35 %, and improved energy recovery by 26.32 % under optimum conditions. Compared to H0 tire crude oil, H1 tire crude oil showed reduced levels of all elements except hydrogen, and was notably sulfur-free, while H0 tire crude oil contained significant amounts of sulfur. GC-MS results indicated that these improvements are attributed to enhanced hydrogenation and desulfurization reactions in the H1 process.

Examining Biogas Potential from Rotting Fruits for Advanced Waste Management, Environmental Conservation, and Sustainable Energy Generation

This research aims to analyze the efforts of Koperasi Gemah Ripah Yogyakarta in converting rotting fruits into biogas as part of waste management at Gamping Fruit Market. The methodology involved interviews, field studies, and a comprehensive literature review from various journals. The research findings are threefold. Firstly, Koperasi Gemah Ripah employs a systematic approach to waste management comprising collection, transportation, and disposal. Secondly, the biogas produced through the processing efforts made by Koperasi Gemah Ripah serves as an alternative energy source, generating electricity. Thirdly, the collaborative partnership between Koperasi Gemah Ripah and the Waste Refinery Center at Universitas Gadjah Mada has been proven to be successful in innovatively managing waste by converting it into biogas. In conclusion, the research underscores the effective waste management strategies implemented by Koperasi Gemah Ripah, showcasing the potential of biogas as a sustainable solution to mitigate environmental damage.

Strategic management of energy consumption and reduction of specific energy consumption using modern methods of artificial intelligence in an industrial plant

Given the importance of energy and its role in sustainable gas production, paying special attention to its consumption indicators in all industries, especially oil & gas is very important. The energy consumption index parameter, which equals the ratio of energy consumption to gas production, is one of the most significant indicators of the gas refinery. Artificial intelligence can be used to evaluate the effects of different parameters and find the factors influencing energy performance. Important variables such as inlet gas from various sources, the energy consumption of each part, and the amount of waste refinery gas are collected on different days of the year, then using the least square support vector machine method and networking and sensitivity analysis of the impact of each variable separately. The role of each in this parameter is determined so that it can be used to provide appropriate solutions to reduce energy consumption and the energy consumption index parameter for sustainable gas production. According to the results of this study, the steam unit has a 14 % impact on the energy consumption index, and the gas sweetening unit has an 18 % impact on gas consumption. So, more research on the optimization of these two units is necessary.

Conversion of Waste Oil from Oil Refinery into Emulsion Liquid Membrane for Removal of Phenol: Stability Evaluation, Modeling and Optimization.

The waste oil emulsion liquid membrane produced by waste oil from oil refineries (WELM) is used to separate the phenol in purified water from the sour water stripper in oil refinery facilities, and the stability of WELM was studied. It is verified that waste refinery oil can be produced into emulsion liquid membrane with good stability and high removal rate for the first time. The WELM stability models were established by response surface methodology (RSM) and artificial neural network (ANN), respectively. The principle and mechanism of various parameters, as well as the interaction effects on the stability of WELM, are proposed. The effects of parameters, including the ratio of Span-80, liquid paraffin, the ratio of internal and oil, and the rotational speed of the homogenizer, were investigated. Under the optimal operating parameters, the WELM had a demulsification percentage of just 0.481%, and the prediction results of RSM and ANN were 0.536% and 0.545%, respectively. Both models demonstrate good predictability. The WELM stability model has a high application value in the treatment of phenol-containing wastewater in the oil refining industry, and provides a green method of resource recovery.

Conceptual carbon-reduction process design and quantitative sustainable assessment for concentrating high purity ethylene from wasted refinery gas

The direct emission of waste refinery gas after combustion will cause a severe greenhouse effect. Recovering high-value-added ethylene from wasted refinery gas has fundamental economic and environmental significance. Due to the complexity of the composition of refinery waste gas, designing and optimizing the whole recovery process is still a challenging task. Herein, a novel process (SCOAS) was proposed to obtain polymer-grade ethylene from wasted refinery gas through a direct separation process, and heat pump-assisted thermal integration optimization (HPSCOAS) was carried out. The unique feature of the novel approach is that a new stripper and ethylene reabsorber follow the dry gas absorber to ensure ethylene recovery and methane content. An industrial model, shallow cooling oil absorption (SCOA), and concentration combined cold separation system of ethylene unit using wasted refinery gas was established to analyze the technology and environment. Based on the detailed process modeling and simulation results, the quantitative sustainability assessment of economy and environment based on product life cycle process is carried out. The results show that compared with the traditional process when the same product is obtained, the total annual cost of the HPSCOAS process is the lowest, which is 15.4% lower than that of the SCOA process and 6.1% lower than that of the SCOAS process. In addition, compared with the SCOA process and the HPSCOAS process, the SCOAS process has more environmental advantages. The non-renewable energy consumed by SCOAS is reduced by about 24.8% and 6.1%, respectively. The CO2 equivalent is reduced by about 38.6% and 23.7%.

Optimized catalytic pyrolysis of refinery waste sludge to yield clean high quality oil products

The production of clean oil products from oily waste can help the oil industry to become more efficient and sustainable. A novel technique is developed that takes waste refinery oily sludge (ROS) as feedstock to produce a clean high quality oil product. The cost of the feedstock supply is very low as ROS is a waste product that is costly to dispose of with potential adverse consequences for the ecosystem if improperly discarded. The novel process involves a two-stage tubular fixed-bed reactor capable of converting the ROS into a clean oil product and simultaneously upgrade its quality. To systematically optimize the process variables, the response surface methodology (RSM) is applied. A meticulous mathematical model with an error of less than 5% estimates the optimum point for achieving the maximum product yield. The upgrading process involves a specifically synthesized, highly selective metal (Ni/Co/Mo) loaded zeolite catalysts. The synthesized catalysts are carefully characterized using XRD, FTIR, ICP, and SEM analysis. The detailed compositions of the upgraded products are also characterized using GC–MS CHNS/O elemental, and GC techniques. Among the synthesized catalysts, the 3 wt% Ni/HZSM-5 catalyst exhibited superior performance in reducing unfavorable oxygen, sulfur, and nitrogen contents in the oil products. Notably, the higher heating value of the upgraded product generated with nickel-zeolite catalysts (Ni/HZSM-5) is 44.24 MJ/kg which is in the range of naturally occurring crude oils (typically 42 to 47 MJ/kg). This feature highlights the quality and value of the final product.

Concept for Biomass and Organic Waste Refinery Plants Based on the Locally Available Organic Materials in Rural Areas of Poland

The importance of developing efficient and environmentally friendly means of biomass conversion into bioenergy, biofuels, and valuable products is currently high in Poland. Accordingly, herein, two new energy and biofuel units are proposed, namely, POLpec and POLbp, which are used as reference sources for comparing energy consumption and biofuel production in other countries or regions in the world. One POLpec equals 4400 PJ (195.1 Mtoe), reflecting the annual primary energy consumption of Poland in 2020. Meanwhile, one POLbp equals 42 PJ (1.0 Mtoe), referring to the annual production of biofuels in Poland in 2020. Additionally, a new import–export coefficient β is proposed in the current study, which indicates the relationship between the import and export of an energy carrier. More specifically, the potential of biomass and organic waste to be converted into energy, biofuels, and valuable products has been analysed for the rural areas of Poland. Results show that the annual biomass and organic waste potential is approximately 245 PJ (5.9 Mtoe). Finally, the concept of a biomass and organic waste refinery plant is proposed based on the locally available organic materials in rural areas. In particular, two models of biomass refinery plants are defined, namely, the Input/Output and Modular models. A four-module model is presented as a concept for building a refinery plant at the Institute of Technology and Life Sciences—National Research Institute in Poznan, Poland. The four modules include anaerobic digestion, gasification, transesterification, and alcoholic fermentation. The primary reason for combining different biomass conversion technologies is to reduce the cost of biomass products, which, currently, are more expensive than those obtained from oil and natural gas.

The Preparation of Eco-Friendly Magnetic Adsorbent from Wild Water Hyacinth (Eichhornia crassipes): The Application for Removing Lead Ions from Industrial Wastewater

Water hyacinth ( Eichhornia crassipes) is a wild floating plant that can be found widely in pond or river areas. The plant grows fiercely and causes many harmful issues to the ecosystem around its covered area. This work provides a utilization method that converts wild water hyacinth to reliable magnetic biochar which can be used as a very effective adsorbent for the removal of lead ion Pb(II) in industrial wastewater. The mentioned magnetic biochar can be prepared via a modified pyrolysis process at 550°C with the support of cobalt sulfates as magnetite precursors and limited oxygen from the sweeping gas (the gas mixture ratio is 4 : 1 nitrogen/oxygen). The produced samples were hydrophobic biochar with high oxygen-containing functional groups that are suitable for the removal of inorganic contaminants. The impregnation of cobalt (II, III) oxides provided high magnetic separation performance and additional adsorption sites on the produced magnetic biochar. As indicated by the obtained result, the WHB-Co2M sample possesses a highly porous structure (0.126 cc/g), higher thermal stability (thermal durability reaches 900°C), relatively stable magnetic properties (14.74 emu/g), and a larger surface area (192 m2/g). These beneficial properties led to its suitability to serve as an adsorbent in removing lead ions in the contaminated effluent, recording 95% of removal efficiency and adsorption capacity of 67.815 mg/g. As indicated in the result, all prepared magnetic biochar samples were fitted to two-parameter (Langmuir models) and three-parameter (Sips model) isotherm models. Therefore, the adsorption process in this work could be carried out on both homogeneous and heterogeneous adsorbent surfaces. The adsorption kinetics of the removal process also was described by the pseudo-first-order, pseudo-second-order, and Elovich models to reveal the adsorption and desorption rate of the as-prepared magnetic biochar. This work indicates a successful waste refinery route of converting lignocellulosic biomass such as water hyacinth into value-added material for use as promising heavy metal adsorbents.

Kinetic modeling for the catalytic cracking of tires pyrolysis oil

The parameters of a 6-lump kinetic model for the catalytic cracking of tire pyrolysis oil (TPO) in conditions of the industrial fluid catalytic cracking (FCC) unit have been computed. The experiments have been carried out in a riser simulator reactor, on a commercial equilibrium catalyst at the following conditions: 500–560 °C; catalyst/oil ratio (C/O), 3–7 gcat gTPO-1; and reaction time, 1–10 s. The most significant catalytic steps for conversion levels below 80% are those in which the heavy cycle oil (HCO) lump is involved, either cracked to form light cycle oil (LCO), naphtha, liquefied petroleum gases (LPG), dry gas or condensed to coke. For higher levels of conversion, LCO and naphtha lump over-crack causing exponential increases in the yields of LPG, dry gas and coke. It should be highlighted the high yield of naphtha obtained (48 wt%) for a conversion of 90% at 530 °C. It is also remarkable the low deactivation level by coke deposition, since the coke formed on the acid sites of the catalyst is not much condensed. The results are of great interest for the design or reactors ad hoc for the catalytic cracking of TPO in conditions similar to those of industrial FCC unit, as well as for its feeding to a commercial unit within the strategy involved in the Waste Refinery.

Assessment of plastic waste generation and its feasibility for establishment of plastic waste refinery

Assessment of plastic waste generation and its feasibility for establishment of plastic waste refinery

Waste Refinery: The Valorization of Waste Plastics and End-of-Life Tires in Refinery Units. A Review.

This review collects a wide range of initiatives and results that expose the potential of the refineries to be converted into waste refineries. Thus, they will use their current units for the valorization of consumer society wastes (waste plastics and end-of-life tires in particular) that are manufactured with petroleum derivatives. The capacity, technological development, and versatility of fluid catalytic cracking (FCC) and hydroprocessing units make them appropriate for achieving this goal. Polyolefinic plastics (polyethylene and polypropylene), the waxes obtained in their fast pyrolysis, and the tire pyrolysis oils can be cofed together with the current streams of the industrial units. Conventional refineries have the opportunity of operating as waste refineries cofeeding these alternative feeds and tailoring the properties of the fuels and raw materials produced to be adapted to commercial requirements within the oil economy frame. This strategy will contribute in a centralized and rational way to the recycling of the consumer society wastes on a large scale. Furthermore, the use of already existing and, especially, depreciated units for the production of fuels and raw materials (such as light olefins and aromatics) promotes the economy of the recycling process.

Towards waste refinery: Co-feeding HDPE pyrolysis waxes with VGO into the catalytic cracking unit

The co-feeding of high-density polyethylene pyrolysis waxes (HDPE waxes) with vacuum gasoil (VGO) on the catalytic cracking has been investigated. Runs have been conducted by feeding a blend of HDPE waxes/VGO (1/4 in mass) to a laboratory-scale reactor that mimics the behavior of the riser reactor of the industrial FCC unit. Tested operating conditions have been the following: 500–560 °C; catalyst to oil mass ratio (C/O), 3–7 gcat gfeed−1; and, contact time, 6 s. The comparison of obtained results, i.e., yield and composition of the fractions, in the cracking of the blend with those obtained in the cracking of the VGO and HDPE waxes separately, has exposed the existence of synergetic mechanisms. This way, the cracking of the blend produces a more olefinic gaseous fraction and a naphtha with higher content of iso-paraffins and olefins and lower of aromatics, together with a comparable yield of coke.

Assessing the potential of the recycled plastic slow pyrolysis for the production of streams attractive for refineries

The slow pyrolysis of recycled high-density polyethylene (HDPE) has been investigated in a batch autoclave reactor at 430–490 °C and reaction times of 15–60 min, with the aim of obtaining the maximum yield of plastic oil (PO) with an adequate composition for its subsequent valorization in refinery. Specifically, PO yields up to 85–90 wt% have been achieved operating at 430 °C and 15–37.5 min, noting that the obtained yields strongly depend on temperature and, to a lesser extent, on reaction time. Simulated distillation and gas chromatography analyses of PO have shown its potential for its valorization in a waste refinery scheme targeting the production of alternative fuels. Thus, the PO obtained at 430 °C and 15 min is suitable to be cofed to the fluidized catalytic cracking (FCC) unit since it has a simulated distillation curve similar to that of vacuum gasoil (VGO). On the other hand, the PO obtained at 430 °C at the longest reaction time and those obtained at 460 °C are suitable to be fed together with light cycle oil (LCO) into a hydroprocessing unit. The composition of naphtha and middle distillates of PO reveals that these fractions are appropriate for their blending with commercial diesel and gasoline pools after a mild hydrotreating to reduce their olefin content.

Biosurfactant Facilitated Emulsification and Electro-osmotic Recovery of Oil from Petrochemical Contaminated Soil and Oily Sludge

Petroleum industries are burdened with the problem of handling petroleum products, petroleum waste products and refinery byproducts such as large quantities of oil waste. Improper management of these products and their wastes present an environment hazard when they end up in the atmosphere, water and land due to their hazardous constituents. An evaluation to determine the possibility of enhancing the electrokinetic process by application of a biosurfactant producing strain for remediation of petroleum contaminated soil through oil recovery and hydrocarbon degradation was studied at a bench scale. A DC powered electrokinetic reactor consisting of electrode/electrolyte compartments and a medium chamber was used under voltage variations of 10 V and 30 V with an electrode spacing of 185 mm. Biosurfactant with its producing microbes and biosurfactant free cells were introduced in the soil chamber after which the reactor was left to run for 10 days under the electric field. The technology was able to achieve the highest oil recovery of 75.15 % from the soil in 96 hours at 30 V. The microorganisms were able to survive under the electric field there by leading to further reduction of the carbon content in the reactor.

Estimation of global warming emissions in waste incineration and landfilling: An environmental forensic case study

Anthropogenic emissions of greenhouse warming gases (GWG) to the atmosphere are thought to contribute to the Earth’s global warming. Among different waste management options, incineration is often considered one of the most effective and environmentally protective as demonstrated by many Life Cycle Assessment analysis. Nonetheless, depending on previous treatments that a waste may receive, such as mechanical biological treatment (MBT), landfilling could offer better possibilities than incineration in terms of GWG emissions thanks to carbon sequestration according to the “Carbon Sink” principle. The latter refers to any process that avoids the emission of GWG, for example, the biogenic carbon that is not dissimilated and remains permanently stored in a landfill, avoiding its emission to the atmosphere. The current study presents a forensic case study of municipal solid waste management in Italy; it aims at assessing the GWG [i.e., methane, carbon dioxide (CO2), and nitrous oxide] released to the atmosphere by two different scenarios of a waste flow processed in a MBT: incineration with energy recovery and landfill disposal with gas recovery. For each scenario, total fluxes of GWG are estimated as the sum of: 1) emissions during waste refinery to produce refuse-derived fuel; 2) indirect emissions associated to transport; 3) process or treatment emissions derived from the waste itself (direct emissions) and from the fuel used for its treatment prior to disposal; 4) disposal emissions that result from the ultimate disposal of the waste; 5) emissions avoided as a result of useful energy or materials recovery; 6) stored or sequestered emissions due to short-cycle carbon locked up in the landfill and prevented from being returned to the atmosphere as CO2 for longer than 100 years. Carbon sink is a fundamental phenomenon to be accounted in the study, given that, without considering it, the GWG in the landfill would considerably change (from –33.9 kg CO2/t DF to 250.3 kg CO2/t DF, DF being the dry fraction from the MBT process). According to the composition of waste and to the plant engineering for the treatment/disposal destinations assumed, landfilling results the better option in term of GWG emissions. It is worth mentioning that not only GWG should be considered in the evaluation of waste management options. Nonetheless, the results from the present study provide useful information to prove that a waste management option (landfilling), that a priori could appear less sustainable, represents, instead, an optimal solution.

High-efficiency removal of lead from wastewater by biochar derived from anaerobic digestion sludge

The properties of biochar derived from waste activated sludge and anaerobic digestion sludge under pyrolysis temperature varying from 400°C to 800°C were investigated. The heavy metals adsorption efficiency of the sludge-derived biochar was also examined. Among the biochar samples tested, ADSBC600 possessing highly porous structure, special surface chemical behaviors and high thermal stability was found to remove Pb2+ from aqueous solutions efficiently with an adsorption capacity of 51.20mg/g. The Pb2+ adsorption kinetics and isotherm for ADSBC600 can be described using the pseudo second-order model and Langmuir isotherm, respectively. Analysis of the characteristics of biochar before and after metal treatment suggests that electrostatic attraction, precipitation, surface complexation and ion exchange are the possible Pb2+ removal mechanisms. This study demonstrates a successful example of waste refinery by converting anaerobic digestion sludge to feasible heavy metal adsorbents to implement the concept of circular economy.

Identification of two new keratinolytic proteases from a Bacillus pumilus strain using protein analysis and gene sequencing.

The Bacillus strain (CCUG 66887) has a high capacity to excrete keratinase with the ability to degrade both alpha- and beta keratin. In this study we aimed to show the characteristics of the keratinolytic protease and to identify its gene by using liquid chromatography–electrospray ionization tandem mass spectrometry methods (nanoHPLC–ESI–MS/MS) followed by Mascot data base search. The results showed that the enzyme in fact consists of two different keratinases, both with a molecular mass of 38 kDa. Further, DNA sequencing generated the open reading frame (ORF) of one of the genes (Ker1), and de novo genome sequencing identified the ORF of the second gene (Ker2). The two keratinase genes contain 1153 base pairs each and have a gene similarity of 67 %. In addition, the Bacillus strain was classified as Bacillus pumilus and its genes were annotated in the GeneBank at NCBI (accession: CP011109.1). Amino acid sequences alignment with known B. pumilus proteases indicated that the two keratinases of B. pumilus strain C4 are subtilisin-like serine proteases belonging to the Protease S8 family. Taken together, these result suggest the two keratinases as promising candidates for enzymatic processing of keratinous wastes in waste refinery.

The Modifying Additive for Concrete Compositions Based on the Oil Refinery Waste

The use of chemical and mineral additives is the most effective way to improve the quality of the concrete, and to give them specific properties. Expansion of the range of the chemical additives of compound action through the use of oil refinery waste of enterprises in the region is a relevant and economically feasible task. Surfactants derived from petrochemical synthesis products and substances formed during refining, are not only inexpensive and abundant, but also significantly exceed the additives of the natural origin by their technical properties. Therefore, the analysis of oil refinery waste applicability as a modifying additive for concrete is of a scientific and practical interest. The decline in water absorption by 2 - 2.5 times, the density increase by 10% on average, an increase in the strength of concrete indicators of the modified compositions, gives grounds to define organic waste refinery as a chemical additive that improves the physical and mechanical properties of concrete. The experimental results enable one to recommend it for modification of concrete and concrete mixtures in the production of both construction and repair work at the facilities of industrial enterprises, residential buildings, houses, boiler house foundations, etc.

Production of Bio-plastics (Polyhydroxy Butyrate) from Industrial Effluent using Batch and Two Stage Batch Culture Studies

The present study focuses on the improvement of production of Poly Hydroxy Butyrate (PHB) using Bacillus megaterium MTCC 8075. The culture media and conditions were studied critically and was found that the maximum PHB production was attained in the presence of glucose as carbon source at 6% concentration with a yield of 55.0 mg/g cell weight and peptone as nitrogen source with a yield of 17.2mg/g cell weight. The optimum pH was found to be 7(22.8mg/g) and it was also investigated that PHB production was maximum corresponding to a temperature of 35°C (35.46mg/g) and at an incubation time of 72 hours (52.2mg/g). PHB was qualitatively analysed using Sudan Black staining method, extracted using sodium hypochlorite, and quantified using crotonic acid assay in UV spectrophotometer at a wavelength of 235nm. PHB production was carried out in various selected effluents like corn stalk waste and petroleum refinery effluent and corn corb yielded the maximum PHB production of 3.1mg/L. The produced PHB was confirmed using Fourier Transform Infrared (FTIR) analysis and NMR spectroscopic studies. PHB production was further improved using two-stage batch culture studies in which PHB production was compared in various nutrient limited conditions of nitrogen and phosphorous. The thermal properties of PHB was studied using Differential Scanning Calorimetry(DSC) and Thermogravimetric Analysis (TGA).

Carbohydrate-derived Solid Acid Catalysts for Biodiesel Production from Low-Cost Feedstocks: A Review

Currently, most biodiesels are produced from virgin vegetable oils using a transesterification reaction. However, there are a number of other potential cheap sources for biodiesels, such as deep-frying oils/fats and palm fatty acid distillate (PFAD). PFAD is a lower-value by-product of the palm oil industry and is an economical source for biodiesel production. Due to the high cost of biodiesel production, the formulation of a new method to produce a cheaper biodiesel is imperative. Low-quality feedstocks (especially PFAD) using green and highly reusable catalysts have gained popularity due to their low production cost. High free fatty acids (HFFA) in the feedstock causes problems during the biodiesel production process, especially with the use of basic heterogeneous and homogenous catalysts. Recently, the effectiveness of a solid acid catalyst to catalyze biodiesel production from HFFA feedstock has caught the attention of researchers.This comprehensive article explores the use of low-quality feedstocks and carbon-based catalysts for the conversion of a waste refinery crude palm oil product which contains a high percentage of FFA. The production and characterization of carbohydrate-derived solid acid catalysts are discussed, including their physico-chemical property measurements. Techniques used for the synthesis of biodiesels are also included. In addition, transesterification process variables such as the oil/methanol molar ratio, catalyst concentration, reaction time, and temperature are investigated. The final part of the article contains the combustion, emissions, and performance of produced biodiesels. Finally, conclusions, including perspectives and future developments, are also presented. The aim of this article is to demonstrate the current state of the use of low-quality feedstocks and green heterogeneous solid acid catalysts for the use in biodiesel production.