Plant Scale Research Articles

Sensor Set Decomposition for Enhanced Distributed Sensor Fault Isolability of Marine Propulsion Systems

This paper proposes a greedy stochastic optimization algorithm for the sensor set decomposition used in the sensor fault monitoring of marine propulsion systems, based on fault isolability criteria. These criteria are expressed mathematically in terms of the number of unique columns in the theoretical fault signature matrices (FSMs) used during the sensor fault isolation process. Due to the large scale and complexity of marine propulsion plants, the diagnostic layer follows a distributed architecture with a combinatorial logic used for fault isolation in two cyber levels; the local and global decision logic. As a result, the FSMs of both levels are formulated as an integrated optimization problem. Each solution regarding the sensor set decomposition is then used to generate the respective distributed monitoring architecture, using semantic (qualitative) knowledge for the propulsion plant. Thus, the need for an analytical model of the plant is removed. Moreover, based on the design of the distributed monitoring architecture, the respective theoretical FSMs (quantitative) are Automatically generated and used for the evaluation of the objective function. Finally, simulation results are used to illustrate the application of the greedy stochastic optimization algorithm and its efficiency.

Kinetics of Electron Transfer Reaction Between Co(II) and Chlorate Ions: Isothermal Reactor Design and Experimental Validation

The Batch Stirred Tank Reactor (BSTR) has been commonly used for decades in the chemical process industries and even on a pilot plant or laboratory scale whenever expensive and delicate raw materials and products such as pharmaceuticals or fragile transition metal complexes are involved. This research article describes the details of isothermal BSTR and subsequent experimental validation of the rate law discovered in the previous paper of this series on the electron transfer reaction between Co(II) and chlorate ions in acetic acid solution. A Series of tests were performed to evaluate the efficiency of the BSTR at multiple temperatures and illustrate the differences between the theoretical and experimental conversion of potassium chlorate through relative error. The experimental conversions are calculated with the design equation. Theoretical and experimental conversions are correlated and proportional to the initial concentrations of the reactant and electron transfer reaction among the reactants. Based on the parameters of the design equation, a set with average parameters was chosen and tested over BSTR. The model was then validated for different temperatures and conversions. A design equation for the BSTR has been written and applied for the conversions of 25%, 50%, 75%, and 95%. The time interval is going to be predicted by the model to achieve the desired conversions. The percent relative error between predicted and experimental conversions clearly shows the modeland#39;s predictability, power, and reliability. The precision of the observed rate constant for the electron transfer reaction is found to be 2.2023and#215;〖10〗^(-2 )%

Infrared thermography monitoring of solar photovoltaic systems: A comparison between UAV and aircraft remote sensing platforms

The continuous increase in the number and scale of solar photovoltaic power plants requires the implementation of reliable diagnostic tools for fault detection. With the recent advances in low-weight, high-precision, and fast-response thermal cameras, along with professional aerial platforms, aerial infrared thermography (aIRT) is currently the most popular method for non-destructive, fast, and relatively inexpensive monitoring of photovoltaic (PV) power plants. Typically, aerial inspections are conducted using a UAV (drone) equipped with a thermal camera to produce a report indicating detected thermal defects, typically associated with failures. The main purpose of this paper was to compare the thermographic results for two different PV plants provided by two remote sensing-based approaches: the classical UAV-mounted thermal camera survey and the inspection by high-speed thermal cameras mounted on an airplane. The post-processing of thermal patterns showed good agreement between the results provided by the two aerial platforms, with an overlap of thermal anomalies detected up to 98%. An economic analysis demonstrated that, while airplane surveys incur higher costs (compared to UAV surveys) due to the hire of vehicles and more expensive instrumentation, they, on the other hand, require a reduced amount of time and may be more convenient when inspecting large-scale PV plants or multiple PV plants located within a close area.

Economics of renewable hydrogen production using wind and solar energy: A case study for Queensland, Australia

This study presents a technoeconomic analysis of renewables-based hydrogen production in Queensland, Australia under Optimistic, Reference and Pessimistic scenarios to address uncertainty in cost predictions. The goal of the work was to ascertain if the target fam-gate cost of AUD 3/kg (approx. USD 2/kg) could be reached. Economies of scale and the learning rate concept were factored into the economic model to account for the effect of scale-up and cost reductions as electrolyser manufacturing capacity grows. The model assumes that small-scale to large-scale wind turbine (WT)-based and photovoltaic (PV)-based power generation plants are directly coupled with an electrolyser array and utilises hourly generation data for the Gladstone hydrogen-hub region. Employing first a commonly used simplified approach, the electrolyser array was sized based on the maximum hourly power available for hydrogen production. The initial results indicated that scale-up is very beneficial: the levelised cost of green hydrogen (LCOH) could decrease by 49% from $6.1/kg to $3.1/kg when scaling PV-based plant from 10 MW to 1 GW, and for WT-based plant by 36% from $5.8/kg to $3.7/kg. Then, impacts on the LCOH of incorporating curtailment of ineffective peak power and electrolyser overload capacity were investigated and shown to be significant. Also significant was the beneficial effect of recognising that electrolyser efficiency depends on input power. The latter two factors have mostly been overlooked in the literature. Incorporating in the model the influence on the LCOH of real-world electrolyser operational characteristics overcomes a shortcoming of the simplified sizing method, namely that a large portion of electrolyser capacity is under-utilised, leading to unnecessarily high values of the LCOH. It was found that AUD 3/kg is achievable if the electrolyser array is properly sized, which should help to incentivise large-scale renewable hydrogen projects in Australia and elsewhere.

Accelerated integrated watershed management enhances agricultural carbon sequestration and water use efficiency in an endorheic basin

With the continuous promotion of integrated river basin management (IRBM) in endorheic watersheds, the oasis surface processes have undergone significant changes. However, these underlying surface characteristics have not been well integrated into models for simulating carbon-water flux thus far. In this work, a regional SWAT-TECO model was constructed by coupling the modified TECO simulator with irrigation, film mulching, and soil hydraulic redistribution processes within the SWAT framework. The results indicated that the carbon sequestration and water use efficiency (WUE) showed an increasing trend after IRBM implementation in Heihe endorheic basin. WUE was projected to improve under future climate change and can be further enhanced by a maximum of 6.37 % through improving irrigation water use efficiency by 20 %, maintaining existing planting scale, increasing film mulching by 20 %, and reducing fertilizer application by 10 %. These findings can guide the formulation of high-water efficiency agricultural management strategies in global endorheic basins.

Leaf-age and petiole biomass play significant roles in leaf scaling theory.

Foliage leaves are essential for plant survival and growth, and how plants allocate biomass to their leaves reveals their economic and ecological strategies. Prior studies have shown that leaf-age significantly influences leaf biomass allocation patterns. However, unravelling the effects of ontogeny on partitioning biomass remains a challenge because it is confounded by the effects of environmental factors. Here, we aim to elucidate whether leaf-age affects the allocation to the lamina and petiole by examining leaves of known age growing in the same general environmental context. We sampled 2698 Photinia serratifolia leaves developing in the same environment from April to November 2021, representing eight leaf-ages (n > 300 for each leaf-age). Petiole and lamina biomass, and lamina area were measured to evaluate the scaling relationships using reduced major axis regression protocols. The bootstrap percentile method was used to determine the differences in scaling exponents among the different leaf-ages. ANOVA with Tukey's HSD was used to compare the ratios of petiole and lamina biomass to lamina area across the leaf-ages. Correlation tests were used to determine if exponents, intercepts, and ratios differed significantly across the different leaf-ages. The data indicated that (i) the ratio of petiole and lamina biomass to lamina area and the scaling exponent of lamina biomass versus lamina area correlate positively with leaf-age, and (ii) the scaling exponent of petiole biomass versus lamina area correlates negatively with leaf-age. Leaf maturation process involves an inverse proportional allocation between lamina and petiole biomass for expanding photosynthetic area. This phenomenon underscores the effect of leaf-age on biomass allocation and the importance of adopting an ontogenetic perspective when entertaining plant scaling theories and unravelling the principles governing shifts in biomass allocation throughout the leaf lifespan.

Dynamic switched periodic event‐triggered control systems under denial‐of‐service attacks

AbstractPeriodic event‐triggered control (PETC) can save network bandwidth and sensor energy at the same time; therefore, it is a promising approach for applications, especially large scale plants, such as smart water distribution systems. This work extend PETC by considering denial of service (DoS) attacks. For the PETC, a dynamic variable is introduced with a switched strategy. Different from other dynamic variables, our variable keeps store energy when there is no attacks and only release energy when attacks happen. Thus, the inter‐event intervals when attacks happen can be prolonged while guarantees the same stability and performance. If the variable equals to 0 before the ending of the attacks, then characteristic of the attack duration is analyzed to guarantee a slower Lyapunov convergence rate. The presented approach is verified via a numerical example from smart water distribution systems.

Modeling of summer maize transpiration considering morphogenesis

Plant transpiration research is the foundation for improving the efficiency of agricultural water resource utilization and ensuring food production safety. It is an important content of agricultural production and water resource utilization research. However, spatial heterogeneities of leaf size and positions affect the estimation of transpiration. In this study, summer maize on the North China Plain was taken as the research object. Based on the measured data of the photosynthetic apparatus, morphogenesis and stem flow meter, the transpiration variation rule of summer maize leaves was analyzed, and the spatial distribution model of photosynthetically active radiation based on plant morphogenesis was constructed. Considering the spatial heterogeneities of leaf size and positions, the individual-plant scale transpiration model was upgraded. The reliability of transpiration model at individual plant scale was verified. The results showed that: i) the transpiration rate of leaves with different leaf positions, positive and negative leaves at the same leaf position and different parts of the same leaf were significantly different. ii) Based on the measured data, the structure of summer maize with spatial coordinates was obtained, and a calculation model for solar radiation reaching the top of the plants and a calculation model for photosynthetically active radiation reaching the surface of the leaves were constructed. Based on the different absorption, reflection, and transmission of radiation by summer maize leaves, the photosynthetically active radiation of each part of the leaves was characterized. iii) A plant transpiration model was constructed by combining the leaf panel transpiration model with the spatial distribution model of photosynthetically active radiation in summer maize plants, and, the determination coefficients between the simulated and the measured values of the individual plant scale transpiration rate were all above 0.95, the consistency index was close to 1.0, and the RMSE was in range of 12.41–16.64 g h−1. The individual plant transpiration obtained after simulated accumulation could meet the simulation accuracy. The results achieved the scale improvement of the leaf transpiration to individual plant transpiration.

Using repeat UAV-based laser scanning and multispectral imagery to explore eco-geomorphic feedbacks along a river corridor

Abstract. Vegetation plays a critical role in the modulation of fluvial process and morphological evolution. However, adequately capturing the spatial and temporal variability and complexity of vegetation characteristics remains a challenge. Currently, most of the research seeking to address these issues takes place at either the individual plant scale or via larger-scale bulk roughness classifications, with the former typically seeking to characterise vegetation–flow interactions and the latter identifying spatial variation in vegetation types. Herein, we devise a method which extracts functional vegetation traits using UAV (uncrewed aerial vehicle) laser scanning and multispectral imagery and upscale these to reach-scale functional group classifications. Simultaneous monitoring of morphological change is undertaken to identify eco-geomorphic links between different functional groups and the geomorphic response of the system. Identification of four groups from quantitative structural modelling and two further groups from image analysis was achieved and upscaled to reach-scale group classifications with an overall accuracy of 80 %. For each functional group, the directions and magnitudes of geomorphic change were assessed over four time periods, comprising two summers and winters. This research reveals that remote sensing offers a possible solution to the challenges in scaling trait-based approaches for eco-geomorphic research and that future work should investigate how these methods may be applied to different functional groups and to larger areas using airborne laser scanning and satellite imagery datasets.

Evaluating the relationship between stem and leaf biomass as well as stem length and leaf surface area of amaranth cultivars in improving food plant

Amaranth is now cultivated almost all over the World for multiple purposes, such as a vegetable, seed food, feed for animals, medicine, and for industry uses. They are highly nutritious, with vitamins and minerals. Leaf area and leaf dry biomass are key parameters linked to plant growth and production. The relationship between leaf biomass and leaf surface area, as well as stem biomass and stem length, is important to our understanding of plant scaling relationships because of their relationship to plant survival. This paper aimed to evaluate the relationship between and within the leaf and stem parameters of nine different amaranth cultivars. The fresh leaves and stems were weighed in their fresh masses; the surface area for leaves was calculated by drawing a full leaf in square quadrats and then counting the square quadrats occupied by a leaf and the stem length was measured using a ruler. Our results indicated that there was a clear relationship between leaf fresh mass and leaf dry mass but a negative correlation between stem fresh mass and stem dry mass due to different internal contents such as water and substances. A low significance was obtained between leaf biomass and leaf surface area, stem biomass and stem length, and leaf biomass and stems biomass as well as leaf surface area and stem length. Our results revealed that this variability of values causes the disproportional ratio of fresh mass to dry mass due to the differentiation quantity of water and solutes within the leaves and stems.

Population’s preference of rhinoceros beetle (Oryctes rhinoceros) between oil palm (Elaeis guineensis) and coconut palm (Cocos nucifera l.): Contributing to pest’s controlling strategy

The rhinoceros beetle (Oryctes rhinoceros) began to establish itself in Malaysia with the emergence of coconut cultivation. Rhinoceros beetles were well adapted to survive on oil palm (Elaeis guineensis) and coconut (Cocos nucifera L.) trees. Different host plants could have different interactions and food preferences with the Rhinoceros beetle against their host plant, even within the same family. Additionally, climatic change, particularly rainfall, could also influence the population dynamics of O. rhinoceros especially in terms of the biological aspect of the pest. This study was carried out to evaluate the difference in population of rhinoceros beetles between oil palm and coconut palm as a preference host comparison in relation to the climatic factors on the plantation scale. The population of rhinoceros beetles was found to be higher in oil palm as compared to coconut palm. It can be concluded that rhinoceros beetles highly prefer oil palms when compared to coconut palms. This study highlighted the importance of planting similar families in order to reduce the risk of pest attacks. This study also found that climate is one of the factors influences the population dynamics of rhinoceros beetles and puts pressure on plants, subsequently making it a favorable condition for rhinoceros beetles in the field. Interestingly, female rhinoceros beetle in an oil palm field was significantly correlated with the rainfall. Therefore, preventive measures need to be taken during the rainy season, considering the high risk of planting nearby and/or similar plants.

Near-infrared-based quality control of plastic pre-concentrates in lightweight-packaging waste sorting plants

Today's post-consumer plastic recycling is limited by labor-intensive manual quality control (MQC) procedures, resulting in largely unknown pre-concentrate purities. Sensor-based quality control (SBQC) could enable an automated inline quality monitoring and thus contribute to a more transparent and enhanced plastic recycling. Therefore, we investigated the technical feasibility of near-infrared-based SBQC for plastic pre-concentrates in a lightweight packaging waste sorting plant. The developed SBQC method outperformed MQC methods by reducing measurement uncertainties from between ±0.8 wt% and ±6.7 wt% (MQC) to ±0.31 wt% (SBQC) for bale-specific purities at monolayered material flow presentations. In addition, we show that SBQC may even be possible at multilayered material flow presentations, although further research is needed to address identified segregation effects. The demonstrated technical feasibility of SBQC at plant scale represents a major breakthrough as it opens new opportunities in plastic recycling, such as adaptive pricing models and intelligent process control in sorting plants.

Predicting community traits along an alpine grassland transect using field imaging spectroscopy.

Assessing plant community traits is important for understanding how terrestrial ecosystems respond and adapt to global climate change. Field hyperspectral remote sensing is effective for quantitatively estimating vegetation properties in most terrestrial ecosystems, although it remains to be tested in areas with dwarf and sparse vegetation, such as the Tibetan Plateau. We measured canopy reflectance in the Tibetan Plateau using a handheld imaging spectrometer and conducted plant community investigations along an alpine grassland transect. We estimated community structural and functional traits, as well as community function based on a field survey and laboratory analysis using 14 spectral vegetation indices (VIs) derived from hyperspectral images. We quantified the contributions of environmental drivers, VIs, and community traits to community function by structural equation modelling (SEM). Univariate linear regression analysis showed that plant community traits are best predicted by the normalized difference vegetation index, enhanced vegetation index, and simple ratio. Structural equation modelling showed that VIs and community traits positively affected community function, whereas environmental drivers and specific leaf area had the opposite effect. Additionally, VIs integrated with environmental drivers were indirectly linked to community function by characterizing the variations in community structural and functional traits. This study demonstrates that community-level spectral reflectance will help scale plant trait information measured at the leaf level to larger-scale ecological processes. Field imaging spectroscopy represents a promising tool to predict the responses of alpine grassland communities to climate change.

Transformation of brackish water Reverse Osmosis membranes to nanofiltration & ultrafiltration membranes by NaOCl treatment: Kinetic and characterization studies

Thin Film Composite (TFC) Reverse Osmosis (RO) membranes used in desalination, reach their End-of-Life (EoL) due to fouling and chemical degradation and pose disposal problem. Their lifetime can be increased by converting them into Ultrafiltration (UF) or Nanofiltration (NF) membranes. The present work demonstrates a systematic methodology in terms of ‘ppm-h/ppm∙h exposure’ to chemically convert brackish water RO membranes into NF and subsequently into UF membranes using sodium hypochlorite (NaOCl). Post-performance studies of pure water flux, monovalent and bivalent salt rejection are carried at each treatment level. RO membrane has transformed into NF at 3000–3 ppm-h, 2000–6 ppm-h, 3000–6 ppm-h and in to UF membrane beyond 10000–3 ppm-h. Gradual changes in physicochemical properties of membrane during conversion are ascertained from Scanning Electron Microscope (SEM), Atomic Force Microscopy (AFM), Attenuated Total Reflection – Fourier Transform Infrared Spectroscopy (ATR-FTIR), X-Ray Photoelectron Spectroscopy (XPS), contact angle, zeta potential etc. The rate of chlorination of polyamide is derived using XPS elemental data from initial stages of NaOCl exposure, and rate of hydrolysis from the membrane resistance, and pH. The overall rate equation is combination of both. The membrane thickness calculated from the kinetics match with experimental data. This study gives account of depolymerization of polyamide upon NaOCl exposure (ppm-h) which can be useful in chemical recycling/treatment of EoL membranes on a plant scale.

Development and its application of an advanced shaft furnace gasification technology for municipal solid waste in a commercial scale plant

Development and its application of an advanced shaft furnace gasification technology for municipal solid waste in a commercial scale plant

ELECTROCHEMICALLY TREATED LIGNIN IN PHENOLIC RESINS FOR PLYWOOD PANELS

In achieving the European Union's goal of making Europe the first climate-neutral continent by 2050, the scientific community is striving to develop processes and products that are technologically and economically sustainable to replace/substitute fossil-based feedstocks. In this effort, the European project LIBERATE has demonstrated the commercial opportunities of converting low-cost lignin feedstocks into high-value bio sustainable chemicals such as vanillin and mixed phenolic derivatives.Lignin is the largest regenerative source of aromatic organics. In current wood pulping industries, lignin is underutilized and widely considered a side stream primarily exploited for its energy content. A promising approach for the synthesis of biobased fine chemicals is a depolymerisation process for lignin using sodium peroxodicarbonate (PODIC®), an electrochemically produced oxidiser. Within the LIBERATE project, SINTEF has built a pilot scale plant for the electrochemical lignin depolymerisation. The plant provided CHIMAR with the phenol-rich reactor product solution from both kraft and organosolv lignin, which was used as phenol substitutes with up to 50wt% in the formulation of phenol-formaldehyde (PF) resins. These resins have been able to produce successful plywood panels on a laboratory scale. Although their quality is somewhat lower than that of the reference material with traditional PF resin, this work showed that the use of lignin fractions obtained by electrochemical treatment in such an application is possible and promising.

Hydrogen production and conversion to chemicals: a zero-carbon puzzle?

Abstract Hydrogen is currently used as an intermediate product in the chemical (mostly ammonia and methanol) and refining industries. It is produced mostly from natural gas in large scale plants using steam methane reforming, a very mature technology. Hydrogen produced from natural gas has a high carbon footprint, considering that about 6–9 tons of CO2 are co-produced (and emitted to the atmosphere) per ton of produced hydrogen, depending on natural gas composition. For this reason, hydrogen produced from fossil fuels is nowadays named as “grey” hydrogen. The current production of hydrogen is responsible of about 2.5 % of CO2 emissions worldwide. For hydrogen remaining in business, and then becoming a factor in the energy transition period and later, decarbonizing its production is a must. Partially decarbonized hydrogen produced from fossil fuels, through CO2 capture, is named “blue” hydrogen. A completely different path is followed for the production of fully decarbonized, or “green” hydrogen. This path is already commercially available, though on a smaller scale than required for wide industrial application. It is the electrolysis of water, i.e. the use of electric power from renewable sources to break the water molecule into its constituent hydrogen and oxygen. Pros & cons of these two options will be critically examined.

Horizontal flow aerated constructed wetlands for municipal wastewater treatment: The influence of bed depth

The influence of bed depth on the performance of aerated horizontal constructed wetlands was investigated at the pilot plant scale. Two horizontal flow subsurface constructed wetlands (HF) intensified units of different bed depth (HF1: 0.90 m and HF2: 0.55 m, 0.8 m and 0.5 m water level, respectively) were fitted with forced aeration, while a third one (HFc, 0.55 m bed depth, 0.5 m water level) was used as control and not aerated. The three HF units were operated in parallel, receiving the same municipal wastewater pre-treated in a hydrolytic up-flow sludge blanket anaerobic digester. Applied surface loading rates (SLR) ranged from 20 to 80 g biochemical oxygen demand (BOD5)/m2·d and from 3.7 to 6.7 g total nitrogen (TN)/m2·d, while it ranges from 6 to 23 g BOD5/m2·d and from 1.1 to 1.7 g TN/m2·d in the control unit. Removal of total suspended solids (TSS) and BOD5 was usually close to a 100 % in all units, whilst chemical oxygen demand (COD) removal was higher for the HF1 unit (97 % on average, range of 96–99 %) than for HF2 (92 %, 82–98 %) and HFc (94 %, 86–99 %). TN removal reached on average 33 % (16–43 %) in HFc, 37 % (10–76 %) in HF2 and 51 % (21–79 %) in HF1. High TN removal required a longer aeration time for nitrification and higher effluent recirculation ratio to enhance denitrification. The results indicate that artificial aeration and a high bed depth allows to increase the SLR by a factor of 4 in HF1 but only by a factor of 2 in HF2.

Enzymatic glycerolysis for the conversion of plant oils into animal fat mimetics

Substituting animal-based fats with plant-based fats of similar stability and functionality has always posed a significant challenge for the food industry. Enzymatic glycerolysis products are systems formed by converting native triacylglycerols in liquid oils into monoacylglycerols and diacylglycerols, mainly studied in the last few years for their unique structural ability. This study aims to modify and scale up the glycerolysis process of different plant oils, e.g., shea olein, palm olein, tigernut, peanut, cottonseed, and rice bran oils, with the goal of producing animal fat mimetics. The reactions were conducted at 65 °C, with a plant oil:glycerol molar ratio of 1:1, and without the addition of water, using a lab-scale reactor to convert up to 2 kg of oil into solid fat. Product characteristics were comparable at both laboratory and pilot plant scales, supporting the commercial viability of the process. Oil systems containing higher levels of both saturated and monounsaturated fatty acids, such as shea olein and palm olein, displayed higher solid fat content at elevated temperatures and broader melting profiles with significantly higher melting points. Comparison of the thermal softening behavior and mechanical properties of these systems with those of pork, beef, and lamb fat showed their high potential to replace adipose fat in the new generation of plant-based meat analogs.

CONVERSION OF WASTE POLYPROPILENE (PP) USING THE ZEOLITE Ni/ZSM-5 TO LIQUID FUEL

The aim of this study was to determine the quality and application of liquid oil produced by pyrolysis catalytic cracking assisted Ni/ZSM-5 from polypropylene (PP) plastic waste using a pilot plant scale pyrolysis reactor. The product of pyrolysis in the form of crude oil is refinery by a distillation bubble cap plate column which consists of 4 trays that are integrated with pyrolysis to minimize energy. The pyrolysis process is performed in a fixed-bed reactor. Plastic waste (250 g PP) and Ni/ZSM-5 catalyst (25 g) are mixed in a reactor at various temperatures of 350, 370, 390, 410, and 430ºC, heated in the reactor with a heating rate 5,3 ºC/minute to produce vapor which will be distilled, and produce the product liquid, gas, and char. The optimal yield of fuel oil at 390ºC is 239 ml of fuel oil/250 g of PP with a conversion of 79.20 %,wt (72%, liquid and 7.20% gas) the rest is char. The characteristics of the fuel oil products obtained are included in the range of gasoline and kerosene-type fuels, with an average yield value of ºAPI in the range of 51-42 for kerosene-type fuel in trays 1 and 2, and for gasoline-type fuel. has an average ºAPI value in the range of 52-63 in trays 3 and 4.