Potato Processing Plant Research Articles

Sustainability analysis of bioethanol production from grain and tuber starchy feedstocks

A comparative sustainability study of bioethanol production from selected starchy feedstocks that are abundantly available was carried out in this work. This is to ensure the safe, reliable, and efficient production and consumption of fuel-grade bioethanol. The analysis utilised the established economic minimum bioethanol plant capacity of 158,000 m3/annum. The processing flowsheet model utilised was the same for each feedstock. The sustainability study's economic, environmental, and energy perspectives were investigated. The economic and environmental indices were assessed using Superpro Designer and openLCA sustainability software, respectively. Exergy and lost work were subsequently estimated manually with Microsoft Excel. The economic analyses showed that the plants using cassava and sweet potato initially had the highest return on investment (ROI) of 64.41 and 41.96% respectively at a minimum of 80% plants’ capacity utilisation. The break-even point occurs at a bioethanol price of $3.27 per gallon, beyond which positive net present values were obtained for the four processes. The least profitable plant was based on sorghum recording an ROI value of 34.11%. The environmental assessment on the four selected feedstocks showed that the processes based on cassava, corn, sweet potato, and sorghum recorded encouraging global warming potential (GWP) of 0.2452, 0.2067, 2.5261, and 0.2099 kg CO2 equivalent respectively. Cassava and corn emerged as the two most economically viable feedstocks when economic parameters were adjusted to include pollutants emission/discharge costs but with a slight decrease in profitability indices. The lost work analyses showed that distillation columns were the least energy-efficient units in the four bioethanol production routes assessed, recording loss work of about 61, 68, 34, and 49 MW for cassava, sweet potato, corn, and sorghum processing plants respectively. However, the net energy balance (NEB) and energy renewability results of the four production routes showed that the processes utilising the four selected starchy biomass feedstocks are more sustainable compared to fossil fuels.

Amylolytic microorganisms from diverse tropical environments: Isolation, identification, and amylase production

AbstractThis study aimed to identify microbes producing amylases from diverse unexplored environments in Kenya. Screening based on microorganisms' ability to grow on minimal media (M9) supplemented with starch resulted in the selection of 70 amylolytic isolates. The isolates were then subjected to primary screening based on starch hydrolysis ratio (SHR) obtained by halo formation on starch agar plates after flooding plates with Lugol's iodine solution. SHR narrowed down the isolates' number to 17 (SHR > 1.5), which were used for subsequent experiments. The 17 isolates were grown on M9 starch broth for the production of amylases. Crude amylases and commercial enzyme (control) were assayed for amylase activity using the 3,5‐dinitrosalicylic acid method. Specific enzyme activities of crude enzymes ranged between 0.0079 and 0.0629 U g−1, which were lower than 1.7188 U g−1 of the control. Five enzymes with the highest specific enzyme activity were used for cassava hydrolysis. All crude enzymes exhibited higher specific enzyme activity (0.0707–0.1853 U g−1) than the control (0.0052 U g−1) in hydrolyzing cassava. Alkaline lakes had the highest number (4) of isolates whose enzymes had the highest specific enzyme activity, while isolates from potato processing plant waste, termite gut, and black soldier fly gut had a representative each. Isolates with enzymes having the highest specific enzyme activity were identified by DNA sequencing and belonged to Lysinibacillus sp. (four isolates), Alternaria sp. (one isolate), and Bacillus sp. (two isolates). The study demonstrated the presence of microorganisms in tropical environments with amylase activity that can be scaled and optimized for practical applications.

Removal of diluted wastewater from a potato processing plant with laboratory-scale hybrid-constructed wetlands

Removal of diluted wastewater from a potato processing plant with laboratory-scale hybrid-constructed wetlands

What Does it Mean to be Healthy? Hispanics in the Southeastern Idaho Agricultural Industry.

In contrast to many studies of first generation Hispanics residing in the U.S., our study focused on participants of both genders who were formally employed outside the home. The purpose of this study was to explore the meaning of health among southeast Idaho Hispanics employed in the agro-industry. Using qualitative methodology, we interviewed twenty participants employed at a potato processing plant. We found that men and women had differing concepts of health based upon their gender roles and the value placed on work outside the home, which influenced their willingness to access formal health care. Based on our findings, there is a need for public health officials in Idaho to collaborate with employers to develop and implement workplace clinics.

Integrated bioethanol and biomanure production from potato waste

Disposal of potato processing waste and the problem of pollution associated with it is a vital issue that is being faced by the potato processing plants. The conventional peeling methods presently followed in the processing plants for removing the potato peel, also result in the loss of some portion of the mash which is rich in starch. Indiscriminate discharge of the waste causes detrimental effects in the environment, so this problem can be resolved by successful utilization of the waste for the generation of value added products. Hence, the present work focuses on integrated production of bioethanol and biomanure to utilize the waste completely leading to zero waste generation. The first part of the work describes a comparative study of ethanol production from potato peel and mash wastes by employing co-culture of Aspergillus niger and Saccharomyces cerevisiae at various incubation time (24–120h) instead of application of enzymes. The solid state fermentation of potato peel and mash inoculated with co-culture, resulted in bioethanol production of 6.18% (v/v) and 9.30% (v/v) respectively. In the second part of the work, the residue obtained after ethanol production was inoculated with seven different microorganisms (Nostoc muscorum, Fischerella muscicola, Anabaena variabilis, Aulosira fertilissima, Cylindrospermum muscicola, Azospirillium lipoferum, Azotobacter chroococcum) and mixture of all the organisms in equal ratio for nitrogen (N), phosphorous (P) and potassium (K) enrichment. Among them, A. variabilis was found to enrich N, P and K content of the residue by nearly 7.66, 21.66 and 15 fold than that of the initial content, ultimately leading to improved N:P:K ratio of approximately 2:1:1. The application of simultaneous saccharification and fermentation (SSF) for the conversion of potato waste to ethanol and enrichment of residue obtained after ethanol production with microorganisms to be used as manure envisages environmental sustainability.

Comprehensive Evaluation of Dynamic Impact as a Measure of Potato Quality

Comprehensive evaluation of dynamic impact (free fall) of potato tubers were conducted to ascertain relation of drop height, impact surface, water irrigation also the size of tubers on impact parameters such as (bruise area, impact energy, absorbed energy, coefficient of restitution and dynamic stiffness factor). In addition, five different impact surfaces were used namely (cardboard, wood, steel, plastic and foam) on the platform of the equipment. Potato tubers under different water irrigation (fresh water and treated water) were divided into two mass groups (90 -180 g), M1, and (1- 90 g), M2. Tubers dropped from four heights (40, 30, 20, 10 cm) onto the different surfaces and the different impact parameters were measured. Results showed impact damage measured in terms of bruise diameter is highly influenced by the impact surfaces. Steel surface inflicted the greatest impact damage on the tubers. Impact energy of tuber is greatly influenced by drop height and mass of tuber. Tuber, which dropped from heights (40 cm), absorbed the greatest energy indicating that they suffered the most impact damage. Dynamic stiffness factor for tuber was decreased by increasing storage period. Tuber with low dynamic stiffness factor led to more absorbed energy than tuber with higher dynamic stiffness factor. Moreover, designers of potato harvesters, packaging materials, processing plants and handlers of potato tubers to reduce mechanical damage, especially those due to impact and ensure good quality products, can use results obtained.

Analysis of usability of potato pulp as solid fuel

The paper describes an attempt to analyse the usability of potato pulp as a future ecological solid fuel. The analysis of potato pulp, carried out within the framework of the study, comprised the following aspects: assessing energetic values of potato pulp, assessing the effects of burning solid fuel in the form of pellets made of potato pulp, assessing energy expenditures spent on the process of drying and densification of potato pulp. The performed determination of the elemental composition (chlorine, sodium, potassium, phosphorus and nitrogen), examination of energetic values of potato pulp (the humidity of potato pulp, the heat of combustion, the calorific value, and the ash content), as well as examination of densification (pelletisation) of potato pulp, make it possible to conclude that fuel made of potato pulp, in comparison to other types of biomass, could become a very good and attractive type of boiler fuel, and owing to the fact that it is produced in potato processing plants in great amounts, it could be successfully used by the professional power industry.

Ethanol production from potato peel waste (PPW)

Considerable concern is caused by the problem of potato peel waste (PPW) to potato industries in Europe. An integrated, environmentally-friendly solution is yet to be found and is currently undergoing investigation. Potato peel is a zero value waste produced by potato processing plants. However, bio-ethanol produced from potato wastes has a large potential market. If Federal Government regulations are adopted in light of the Kyoto agreement, the mandatory blending of bio-ethanol with traditional gasoline in amounts up to 10% will result in a demand for large quantities of bio-ethanol. PPW contain sufficient quantities of starch, cellulose, hemicellulose and fermentable sugars to warrant use as an ethanol feedstock. In the present study, a number of batches of PPW were hydrolyzed with various enzymes and/or acid, and fermented by Saccharomyces cerevisae var. bayanus to determine fermentability and ethanol production. Enzymatic hydrolysis with a combination of three enzymes, released 18.5 g L −1 reducing sugar and produced 7.6 g L −1 of ethanol after fermentation. The results demonstrate that PPW, a by-product of the potato industry features a high potential for ethanol production.

Concentration by Electrodialysis of L-Ascorbic acid from Wastewater Coming from the Immersion Process at a Potato Processing Plant

Concentration by Electrodialysis of L-Ascorbic acid from Wastewater Coming from the Immersion Process at a Potato Processing Plant

Kinetic evaluation and performance of a mesophilic anaerobic contact reactor treating medium-strength food-processing wastewater

High rate mesophilic anaerobic contact reactors (MACR) represent a proven sustainable technology for a wide range of different industrial effluents. These reactors demonstrate quite similar features to their aerobic counterparts, activated sludge systems. A lab-scale high rate mesophilic anaerobic contact reactor was operated with wastewater originated from a potato-processing plant, at six different loading rates of 1.1–5 g COD/L per day. The operational performance of MACR was monitored from start-up by assessing COD removal efficiency, total volatile fatty acid production and biogas composition. Furthermore, various kinetic models have been successfully applied to the experimental data to determine substrate balance, maximum utilization rate and volumetric methane production. The COD removal efficiencies were found to be 78–92% and the methane percentage of the biogas produced was 80–89%. Additionally, the methane yield coefficient was found to be 0.394 L CH 4/gTCOD rem.

Indicators of water consumption and the quantity of wastewater formed in selected branches of food industry

Indicators of water consumption and the quantity of wastewater formed in selected branches of food industry The studies covered the branches: sugar industry, fruit-and-vegetable processing and potato processing plants. The analyses of water consumption and quantities of wastewater formed in 24 production plants were performed in the paper. A comparison of water and wastewater management in three branches showed that the highest water consumption is in fruit-and-vegetable processing. The data collected in the paper indicates the drop of water consumption in potato as well as fruit-and-vegetable industry. The values obtained for sugar industry indicate that it is the least diversified branch.

An evaluation of a mesophilic reactor for treating wastewater from a Zimbabwean potato-processing plant

An evaluation of anaerobic treatment of potato-processing wastewater using an up flow Anaerobic Sludge Bed (UASB) reactor at 37°C was conducted. Wastewater from a potato-processing plant in Harare, with an average of 6.8 g COD/l, (COD = chemical oxygen demand) a high concentration of total solids (up to 6725 mg/l) and low pH of 4 - 4.9 was subjected to anaerobic treatment in an UASB reactor. The start up period, which was indicated by gas production and stabilization of COD reduction was 21 days. The organic loading rates (OLRs) investigated varied between 1.3 g COD/l/d and 13.1 g COD/l/d, the maximum methane yield was 0.3 l/g CODremoved at an organic loading rate of 6.6 g COD/l/d. An increase in OLRs to values above 13.1 g COD/ l/d resulted in digester failure. The maximum treatment efficiency (TE) in terms of COD reduction achieved was 90% at a hydraulic retention time (HRT) of 2.1 d and OLR of 3.3 g COD/l/d. The TE was reduced at higher reactor influent velocities, with a minimum TE (71%) recorded at HRT of 0.5 d. Total solids (TS) removal was inconsistent with an average reduction around 50% and phosphorus removal was poor and erratic. pH from the effluent oscillated around 7 with a notable decrease from 7.8 to 6.2 at HRT of 0.5 d. Based on these observations, the UASB process has potential to treat potato-processing wastewater as a pretreatment step before discharge into municipal sewerage system of Harare. Key words: UASB reactor, potato wastewater, anaerobic digestion, methane yield, organic loading rate.

Enzymatic Hydrolysis and Ethanol Fermentation of By-Products from Potato Processing Plants

By-products from potato processing plants were liquefied and partially saccharified using three commercially available enzymes, followed by ethanol fermentation by yeast and then hydrolysis by glucoamylase. From 12% (w/w) of fresh potato peel, about 20 mg/mL ethanol was formed in the supernatant via amylase, pectinase, or an enzyme complex; this yield was slightly increased with combinations of these enzymes. Supplementation of substandard mash to potato peel (1:1) as a raw material enhanced the amount of ethanol formation, increasing it to approximately 50 mg/mL by the mixture of all three enzymes. After the addition of yeast and glucoamylase to the partially saccharified material, ethanol formation proceeded gradually and slowed in 12 h with the consumption of fermentable sugars. Galacturonic acid derived from pectin was not fermented and remained in the fermented broth. In the by-products, the conversion rate of sugars to ethanol was estimated to be 42.5%.

An evaluation of a mesophilic reactor for treating wastewater from a Zimbabwean potato-processing plant

Macro-invertebrate assemblages were used as bioindicators to assess the ecological integrity of Rivers Kisat (influenced by urban development) and Kisian (influenced by agriculture) using community attributes and the Index of Biotic Integrity. Six stations, three per river, were selected to correspond to different impact types and intensities along the rivers. Physico-chemical parameters and nutrients were determined for each station on a monthly basis from November 2007 to April 2008. Two-way analysis of variance was used to compare water quality and nutrient parameters, and macro invertebrate community attributes between the two rivers, with the river and station as the main factors. Significant differences were accepted at 95% confidence level. There were inconsistencies in the variation of physico-chemical parameters along the two rivers. However, River Kisat recorded higher values for all physico-chemical parameters considered, except pH and DO. Different indices and metrics representing the structural and functional organization of macro invertebrates were computed and evaluated for responsiveness to physico-chemical parameters and nutrient levels. Macro invertebrate diversity, richness and evenness values failed to delineate stations according to the different levels of degradation they were experiencing. However, the differences were captured by the index of biotic integrity, which separated stations into different classes of quality. River Kisat stations in urban areas scored lowest index values, less than 15 out of 25, while two river Kisian stations scored the highest value, more than 19. The index provided evidence of response to changes in ecosystem integrity exhibited by resident macro invertebrate assemblages to pollution arising from both point and nonpoint sources. Key words : Urban rivers, water quality, physico-chemical parameters, macro invertebrates.

Optimization of Pressure Filter Performance on Mud Solids in a Potato Processing Plant

Optimization of Pressure Filter Performance on Mud Solids in a Potato Processing Plant

Pumping systems improve production at potato processing plant

Pumping systems improve production at potato processing plant

Rapid Estimation of Potato Tuber Quality by Near‐Infrared Spectroscopy

AbstractStarch and protein parameters of potato tubers were estimated by near‐infrared (NIR) spectroscopy measurements of the crude potato mash. Calibration was carried out with a condensed data set of original 1481 individual samples from a varying number of varieties and breeding lines, grown at eight locations over a three‐years period. Validation of the models was performed with an independent data set (n = 133). Starch content of potato tubers was determined with the official under‐water weighting procedure of the EU, and could be predicted with 90% confidence. The NIR model of phosphorus content of starch had a prediction confidence of 53%. Total protein content could be predicted, too (62% confidence), whereas the amount of coagulable protein was not predictable (R2 = 0.25). Despite the different qualification levels of the models, guiding to concrete prediction tools or to a very rough estimation graduating from “low” to “high”, the NIR technique enables potato starch processing plants to optimise both potato starch quality and processing efficiency.

Denitrification potential of industrial wastewaters

Nitrate utilisation batch experiments have been carried out with different agro-food industrial wastewaters. The results obtained were modelled using a modification of the ASM2d to determine the main kinetic and stoichiometric parameters: denitrification rate with fermentation products ( q N−SA) and with fermentable substrates ( q N−SF); fermentation products and fermentable substrates consumption rates, ( q SA) and ( q SF), respectively; yield coefficient with fermentation products ( Y H−SA) and with fermentable substrates ( Y H−SF) and saturation coefficient for growth on fermentation products ( K H−SA). It was found that fermentation products ( S A) and fermentable substrates ( S F) consumption rates can be assumed to be both constant and independent of the agro-food industrial wastewater used, with values of 14.6 and 5.4 (mg S COD g COD- X OHO –1 h –1), respectively. The mean denitrification rates obtained with each agro-food industrial wastewater ranged from 1.5 to 2.5 (mg S N g COD- X OHO –1 h –1), values slightly lower to the obtained with domestic wastewater (2.7 mg S N g COD- X OHO –1 h –1). Given the substrate consumption rate and the denitrification rate, the yields with fermentation products and fermentable substrates for each wastewater were determined. The values obtained for the yields ranged from 0.50 to 0.69 on using S A and from 0.50 to 0.70 on using S F. Having determined these parameters, the denitrification potential (DNP) was evaluated for each agro-food wastewater. Wastewater from slaughterhouses gave the lowest DNP (22.6 mg S N g S COD –1), whereas wastewater from potato and tomato processing plants gave the highest values (126.5 and 128.2 mg S N g S COD –1, respectively), which are very similar to that obtained with domestic wastewater (130.3 and 128.2 mg S N g S COD –1). Taking into account the low N/COD ratio presented in the agro-food wastewaters, the last wastewaters are the most indicated to enhance the nitrogen removal in the WWTP. Finally, a relationship between the denitrification rates of several agro-food industrial wastewaters and their respective S A/( S A+ S F) ratio was obtained. This relationship can be used to estimate the mean denitrification rate of an agro-food industrial wastewater.

Biohydrogen gas production from food processing and domestic wastewaters

The food processing industry produces highly concentrated, carbohydrate-rich wastewaters, but their potential for biological hydrogen production has not been extensively studied. Wastewaters were obtained from four different food-processing industries that had chemical oxygen demands of 9 g/L (apple processing), 21 g/L (potato processing), and 0.6 and 20 g/L (confectioners A and B). Biogas produced from all four food processing wastewaters consistently contained 60% hydrogen, with the balance as carbon dioxide. Chemical oxygen demand (COD) removals as a result of hydrogen gas production were generally in the range of 5–11%. Overall hydrogen gas conversions were 0.7–0.9 L-H 2 /L-wastewater for the apple wastewater, 0.1 L/L for Confectioner-A, 0.4–2.0 L/L for Confectioner B, and 2.1–2.8 L/L for the potato wastewater. When nutrients were added to samples, there was a good correlation between hydrogen production and COD removal, with an average of 0.10 ± 0.01 L - H 2 / g -COD. However, hydrogen production could not be correlated to COD removal in the absence of nutrients or in more extensive in-plant tests at the potato processing facility. Gas produced by a domestic wastewater sample (concentrated 25 × ) contained only 23 ± 8 % hydrogen, resulting in an estimated maximum production of only 0.01 L/L for the original, non-diluted wastewater. Based on an observed hydrogen production yield from the effluent of the potato processing plant of 1.0 L-H 2 /L, and annual flows at the potato processing plant, it was estimated that if hydrogen gas was produced at this site it could be worth as much as $65,000/year.

The application of different techniques to determine activated sludge kinetic parameters in a food industry wastewater

In the present work, a continuous-feed system under steady state conditions (classical method) and a respirometric technique based on oxygen consumption measurements, were used to compare microbial parameters using a wastewater model system of a potato processing plant. The effects of the operating conditions in the continuous aerobic reactor on microbial growth and flora composition were also analysed. Continuous-feed experiments allowed for the calculation of the following biodegradation parameters: maximum substrate consumption specific rate (qSmax) = 0.19 mgCOD (mgVSS)-1·h-1, saturation constant (Ks) = 8.3 mgCOD·l-1, biomass yield (YX/S) = 0.61 mgVSS (mgCOD)-1, biomass decay constant (kd) = 0.04·h-1 and maximum oxygen consumption specific rate (qO2max) = 0.03 mgCOD (mgVSS)-1·h-1. The respirometric technique also allowed for the calculation of kinetic parameters. However, these parameters depended on dilution rate (D) and / or on dissolved oxygen concentration (DO). Values of qO2max and Ks increased with D; qO2max ranged between 0.05 and 0.13 mgO2 (mgVSS)-1·h-1 and Ks between 2 and 26 mgCOD·ℓ-1 for D values varying between 0.01 and 0.15·h-1. Microscope observations showed that sludge composition was a function of dilution rate. Low D values (low soluble organic matter (Ss) and high DO concentrations) yielded sludges mainly formed by floc-forming bacteria; high D values (high Ss and low DO concentrations) yielded sludges mainly formed by filamentous micro-organisms. Since the low substrate / biomass ratios used in the respirometric method limit the growth of micro-organisms maintaining the initial physiological state of the original biomass, the observed differences in the respirometric parameters reflected the actual microbial composition. WaterSA Vol.27(2) 2001: 169-176