The applicability of waste to energy conversion technique is facing many issues because of current waste management practices. Focusing on the segregation issue of low-density polyethylene (LDPE) ...from food waste (FW), microwave (MW) co-pyrolysis of FW and LDPE was investigated in this study. Multifactor optimization of the operating parameters, viz., residence time, LDPE in feed and temperature, was done with response surface methodology to achieve maximum bio-oil yield with a low total acid number (TAN). Bio-oil yield and TAN varied from 17 to 42 wt% and 16–45 mg KOH/g respectively, in various experimental runs. The optimum conditions for maximum bio-oil yield with minimum TAN were residence time −7 s, LDPE in the feed-13% and temperature - 550 °C. A quadratic model was developed to predict bio-oil yield and TAN as a function of operating parameters with an error <8.1 %. Addition of LDPE improved the bio-oil yield (by 20 %). The bio-oil also exhibited reduction in moisture content and TAN (30% and 62 %) and increase in pH and higher heating value (HHV) (40 % and 44 %). Sugars (3.09 wt%), alkanes (1.64 wt%), acids (1.07 wt%), alcohols (0.85 wt%), phenols (0.59 wt%), furans (0.58 wt%) and ketones (0.55 wt%) were the major identified compounds in the bio-oil. Thus, the high HHV and chemical composition of bio-oil indicate its potential use in boilers, engines, turbines, transportation fuels and as a renewable feed for chemical synthesis. The main mechanism for bio-oil quality improvement was the synergetic effect of FW hydrocarbon and hydrocarbon radical (•HC) and hydrogen radical (•H) of LDPE. The energy consumption analysis showed an energy requirement of 13.11 kWh/kg for bio-oil production.
•Microwave co-pyrolysis of food waste (FW) and LDPE to generate bio-oil.•Optimum conditions were 550 °C temperature, 7s residence time & 13 % LDPE in FW.•42 wt% of bio-oil was retrieved under optimum conditions.•Quadratic model was developed to prediction of bio-oil yield and TAN (error <8.1 %).•Addition of LDPE reduced acid, alcohol, furan and phenol percentage in bio-oil.
•First-time fusion of spectral and color features of HSI to predict the total acid content (TAC) and reducing sugar content (RSC) of fermented grains.•CARS-SPA and RC-SPA were conductive to the ...optimization of the detection model.•For TAC and RSC, the RPD value of the model was greater than 19.•This study provides a new method for the rapid and accurate detection of total acid and reducing sugar contents in fermented grains.
Total acid content (TAC) and reducing sugar content (RSC) are important evaluation indicators for the quality of fermented grains. In this study, the TAC and RSC of fermented grains were quantified using hyperspectral imaging (HSI). Two combined algorithms were used to extract the characteristic wavelengths of TAC and RSC. Nine color features of fermented grains were extracted based on H, S and V color channels. Multivariate analytical models were developed to predict TAC and RSC using full wavelengths, characteristic wavelengths, color features and fused data, respectively. The CF model established based on characteristic wavelengths extracted by CARS-SPA showed the best results in predicting TAC. Meanwhile, the PSO-SVR model built using fused data was the best model for predicting RSC. The visualization of the TAC and RSC was achieved using the optimal models. These results show that HSI can achieve non-destructive detection and visualization of TAC and RSC in fermented grains.
Crude oils produced from different reservoirs in the world have very different chemical compositions and physicochemical properties. Naphthenic acids and sulphur content can affect the properties and ...impact the processing and refining of oils. Traditional methods used to determine the total acid number (TAN) and sulphur content are laborious, they use toxic organic solvents, complex analytical procedures and destroy the sample. In contrast the low field nuclear magnetic resonance (LF-NMR) method presents no such inconveniences. LF-NMR was used in this work as an alternative technique in association with multiple linear regression (MLR) to predict the total acid number and the sulphur content in crude oils. Models were built from the LF-NMR to predict TAN and sulphur content in crude oils using the MLR with least squares method. The models presented adjusted coefficient of determination (R2adj) of 0.915 and 0959 for TAN and Sulphur content respectively, and standard deviation of regression of 0.30mg KOH/g and 0.051wt% for TAN and Sulphur content respectively. Finally, this study demonstrated by the first time the potential of LF-NMR as an alternative to potentiometric titration and R-ray fluorescence spectrometry.
Diode-type sensors were fabricated by employing a partially anodized Ti plate and a pair of noble-metal (Pt, Pd, or Au) electrodes, and the effects of the degree of oil deterioration on the various ...electrical properties of the diode-type sensors were investigated in this study. The current–voltage characteristics, current-response behavior under an applied bias voltage, and conductance-response behavior were obviously dependent on the total acid number, TAN, which is a significant parameter for evaluating the degree of oil deterioration, The diode-type sensor using a pair of Pt electrodes showed large responses among all sensors. The sensor responded to proton species dissociated from ethanoic acid in oil as well as dissolved H2 in oil, which is quite important in monitoring the degree of oil deterioration.
•Diode sensors employing anodized TiO2 and noble-metal films were developed.•All diode sensors can monitor the degree of oil deterioration.•All diode sensors respond to proton species dissociated from ethanoic acid in oil.•The diode sensors using Pt or Pd electrodes respond to dissolved H2 in oil.•The diode sensor with Pt electrodes showed the largest current responses.
The study focused on isolation and characterization of a bevy of phosphorus solubilizing bacteria (PSB) and exploring the effects of the most promising PSB on yield and quality of turmeric. For this ...purpose, several bacterial strains isolated from the rhizosphere of turmeric grown across India were assessed for their capacity to solubilize tri-calcium phosphate (TCP) and di-calcium phosphate (DCP) under in vitro condition and in liquid medium. The soluble P turnover by the promising PSB was then investigated in soil per se and their effects were further validated in turmeric under both green house and field conditions for two successive years. The results revealed that Bacillus safensis (NCBI-MT192800), B. marisflavi (NCBI-MT 192801), B. cereus (NCBI- MT192803) and Pseudomonas aeruginosa (NCBI-MZ 540872) released significantly greater levels of labile P in the liquid medium due to their capacity to produce appreciable amounts of organic acids (gluconic, α ketogluconic, succinic, oxalic and tartaric). Green house studies on turmeric indicated that soil available P was significantly higher in the treatments involving PSB suggesting enhanced P solubilization and the treatment with B. safensis + 75 % P as rock phosphate (RP) increased rhizome yield by 129.0 % compared to the treatment with 100 % P applied as RP. The positive effects of PSB were also reflected in field experiments, wherein the treatments with combined application of B. safensis with 50 % or 75 % or 100 % P significantly increased soil available P by 143.0 – 246.0 %, rhizome yield by 29.0 – 120.0 %, P uptake by 51.0 – 223.0 % and curcumin content by 30.0 – 32.5 % compared to control (100 % P as RP). The use of B. safensis ensured 25.0 % reduction in exogenous inorganic P application while simultaneously enhancing turmeric yield and quality in P deficient soil.
•Combined influence of organic acids was critical during P solubilization.•Enhanced soil available P was attributed to increased acid phosphatase activity.•PSB inoculation significantly increased rhizome yield and plant P uptake.•Curcumin, oleoresin and oil contents in rhizomes were markedly enhanced by PSB.•B. safensis strain (NCBI-MT192800) was the most promising PSB for turmeric.
The effects of operating conditions (temperature, residence time, and water contents) of hydrothermal carbonization (HTC) of spent mushroom compost (SMC) waste on the hydrochars (HCs) and liquid ...effluent characteristics were experimentally revised and ranked in increasing order: residence time < dilution factor < temperature. HTC upgraded the energy capabilities by doubling their heating values and increasing their fixed carbon contents four times. HTC also enhanced the soil amendment characteristics of SMC feedstock in terms of increasing the adsorption polar heads concentration, enriching its calcium and heavy metals contents after a thorough inorganic contents evaluation, doubling the surface area and increasing the pore size by a factor of five. When compared against biocoal from torrefaction in another study, HCs contained less toxic oxygenated compounds and had an 11% higher HHV at lower temperature (i.e. lower energy cost). On the other hand, HCs showed higher surface area (25 m2/g at 250 °C in HTC compared to 16 m2/g at 550 °C in pyrolysis), close adsorption characteristic, and comparable energy capabilities (22.72 MJ/kg at 700 °Cs in pyrolysis compared to 20.7 MJ/kg at 250 °C in HTC) to pyrolysis at significantly lower temperature. GCMS along with UV were used to verify the reviewed degradation mechanism and evaluate the effect of process parameters on this mechanism and on the composition and toxicity of the HTC liquid effluent. They showed that acetic and formic acids, ethanol, phenol, and acetaldehyde were the major compounds that had resulted from the degradation of cellulose, hemicellulose, and lignin. Their concentrations increased with temperature and residence time, but was dependent on temperature in the case of increasing the dilution factor. Nevertheless, HTC degradation enhanced the total acids-phenols concentration in the liquid effluent by 700%.
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•HTC upgraded the energy capabilities and soil amendment characteristic of SMC.•HC competed with biochar and biocoal in soil amendment and energy production.•Process parameters ranked as temperature > dilution factor > residence time.•A detailed degradation mechanism for the liquid phase was developed.•HTC produced a liquid phase affluent with acids, alcohols, ketones and phenols.
This work aims to resolve residual film pollution in farmlands and improve tomato quality. The mechanical properties and degradation of PBAT/PLA lignin (MZS) and PBAT/PLA humic acid (FZS) composite ...biodegradable film were analyzed, and its effect on soil temperature and humidity, soil microorganisms, soil physical and chemical properties, tomato yield, and quality was studied. Polyethylene film (PE) was used as a control. The results demonstrate a higher degradation degree of FZS film than of MZS film. The degradation degree of FZS and MZS films reached level 2 and level 1, respectively, after 131 days of film covering. The weight loss rate of FZS and MZS films reached 52.74 % and 57.82 %, respectively, when buried for 160 days. Compared to the coverings of PE and MZS films, FZS film could significantly increase the soil's electric conductivity and organic matter content (p < 0.05). The relative abundance of soil fungi Chaetomium also increased. The yield, soluble solids, vitamin C (Vc), soluble sugar, and lycopene of tomato plants covered with FZS film significantly increased by 6.74 %, 8.75 %, 15.41 %, 8.30 %, and 27.27 % compared to plants covered with PE film, and the total acid and hardness significantly decreased by 24.95 % and 8.46 %, respectively (p < 0.05). Using 10 μm PBAT/PLA humic acid biodegradable film for tomato cultivation in autumn and winter increased the lycopene and decreased the total acid content by changing the soil's physical and chemical characteristics and increasing the content of Chaetomium soil.
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•Provided a new formula for cultivating solar greenhouse tomatoes with new biodegradable film.•An optional biodegradable film is provided in vegetable production to address residual film contamination in farmland.•Covering FZS film can improve tomato quality by increasing soil organic matter and the relative abundance of Chaetomium.•Compared with PE film, the lycopene content of FZS film significantly increased by 27.27%, and the total acid content significantly decreased by 24.95%.
Reactions as the attack by naphthenic and hydrogen sulfide have caused corrosion problems in the petroleum industry due to they affect the crude oil heating furnaces and distillation towers at ...temperatures between 220 and 400 °C. The total acid number (TAN) measurement has been used as a test to quantify the acid compounds in crude oils and has shown to be a reliable indicator of their corrosion degree. However, the standard method for the TAN measurement, ASTM D-644, involves long times, environment unfriendly wastes and high costs for each analysis. A more appropriate method for the TAN determination is implemented in this paper, by correlating Fourier transform infrared spectroscopy (FTIR) spectral data of the samples with the standard method measurements using multivariate regression models. In particular, the intensities and frequencies of their mid-infrared attenuated total reflectance (MIR-ATR) spectra (4000 - 400 cm−1) are used as independent variables of several principal component regression (PCR) and partial least squares regression (PLSR) models. The latter are employed to correlate the spectra with their respective TAN values so as to obtain a suitable prediction model. Twenty-six (26) samples of Colombian crude oils are used for the study with a TAN ranging from 0.1 to 6.8 mg KOH/g crude oil (ASTM D-664). The models are evaluated according to the coefficient of determination (R2), the root mean square error of calibration (RMSEC) and of prediction (RMSEP). The best model is obtained via PLSR using as few as four components (i.e. factors), which attains a calibration R2 of 0.981 and an RMSEC of 0.317 mg KOH/g crude oil, while for prediction it attains an R2 of 0.996 and an RMSEP of 0.160 mg KOH/g crude oil. It is observed that the functional groups COOH, CH3 and CH2 contribute the most to the prediction models. The designed methodology is faster and environmentally friendly since it does not require sample pretreatment and the use of toxic reagents, and of low-cost compared with the standard procedure since FTIR measurements can be easily taken anywhere using a hand-held or portable spectrometer and a laptop.
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•Prediction models were developed via PCA, PCR and PLSR, making 70%–30% calibration-prediction partitions.•A TAN RMSEP of 0.160 mg KOH/g crude oil is obtained using as few as 4 latent variables.•It was found that the functional groups COOH, CH3 and CH2 contribute the most to the TAN value.
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