Crushed Eggshell Research Articles

Anaerobic Co-digestion of Palm Oil Sludge, Cassava Peels, Cow Dung and Ground Eggshells: Process Optimization and Biogas Generation

Indiscriminate disposal of crop and animal wastes has grown in acceptance across the globe as an environmentally hazardous practice. This study used a 225L polyethylene digester that was specially made to produce biogas from anaerobic co-digestion of palm oil sludge, cassava peels, and cow dung using ground eggshells for pH stabilization and a greenhouse for temperature control. Cassava peels, palm oil sludge, cow dung, and water were combined in a ratio of 1:1:2:5.3, respectively, and 1.3 kilograms of crushed eggshells were added. The bio-digestion system generated 650.60 L of cumulative biogas throughout the 30-day sludge retention period. The pH averaged 6.0, and the slurry temperature averaged 34.76oC during digestion, which is favorable for the production of biogas since microbial populations thrive under hospitable conditions. The biogas produced after a hydraulic retention time (HRT) of over 20 days had the highest methane concentration of 60%, while days under 10 HRT had the lowest methane content of 45.5%. On the 13th day of anaerobic digestion, biogas output peaked at 34.90L, and pH and temperature were maintained at 6.5 and 35.0°C, respectively, the ideal ranges for a healthy process. An efficient technique for producing energy in the form of biogas was shown by optimized anaerobic co-digestion of animal and crop waste utilizing ground eggshells and a greenhouse for pH and temperature control. Future research should focus on developing more efficient, cheaper microbial agents, such as enzymes for biological pre-treatment of palm oil sludge to reduce lignin, which negatively impacts biogas generation.

Study of Mechanical Properties Using Carbonized Rice Husk and Eggshell to Prepare Sustainable Concrete and its Viability in Civil Construction

Sustainability has become an increasingly present concern in the construction industry, which has led to a search for more ecological and sustainable alternatives in the production of construction materials. In this context, research references have shown promising results in the use of carbonized rice husk and eggshell. The use of rice husk as a partial substitute for cement in concrete has proven to be effective in reducing environmental impact, since this residue has pozzolanic characteristics, providing greater resistance to the concrete. Eggshell, in turn, has been used as an additive in the production of mortars, providing improvements in the mechanical and thermal properties of these materials. These sustainable solutions in civil construction are aligned with the ESG agenda of companies, which are increasingly seeking minimize the environmental impact of its activities. The study verified through axial compression resistance tests that the composites prepared with 1.5 % (w/w) had superior compressive strength by around 20% compared to the composites prepared with 2 % (w/w). In other words, with a lower concentration it achieved a satisfactory reinforcement effect, better preserving the structure. From the analysis of the diametral compression resistance results, the concentration of 1.5% (w/w) showed a specific reinforcing effect, both with the use of crushed eggshells and with the use of carbonized rice husks dispersed in concrete. The concentration of 1.5% (w/w) showed a specific reinforcing effect, both with the use of crushed eggshells and with the use of carbonized rice husks dispersed in concrete. The lowest content of 1% (w/w) was not enough to reinforce the material, presenting the lowest yield strength values of 2.98 and 3.54 MPa for egg and rice, respectively. The values for 1.5% (w/w) reached values of 4.22 and 4.68 MPa, for egg and rice. Around 20% of the compounds prepared with the highest filler levels, both with crushed eggshell and carbonized rice husk.

Properties of Sustainable Concrete Consisting Crushed Eggshell Waste as Fine Aggregate Replacement

The excessive extraction of sand from riverbeds has adverse effects on river ecosystems and aquatic life. Simultaneously, the disposal of eggshells from certain food manufacturing facilities into landfills contributes to pollution. Incorporating crushed eggshells as a partial replacement for sand in concrete can reduce the demand for natural sand, thus decreasing the need for sand mining from rivers. The present research investigates the effect of crushed eggshells as partial sand replacement on workability, compressive strength, and splitting tensile strength of concrete. Five different concrete mixtures were tested, with crushed eggshells replacing sand at percentages ranging from 0% to 20% by weight. All specimens underwent water curing and were subjected to three tests: slump, compressive strength, and splitting tensile strength. The incorporation of eggshells, finer than sand, reduced workability but showed acceptable strength up to a 10% replacement rate. In conclusion, using eggshells as a sand substitute in concrete production can contribute to a cleaner environment and support river ecosystem sustainability.

Microbial and Antibiotic Resistant E. coli Contamination in Retail Eggs Produced by Alternative and Conventional Rearing Methods

The aims of this study were to determine: i) the presence of total mesophilic aerobic bacteria (TMAB), total psychrophilic aerobic bacteria (TPAB) coliform, E. coli, Enterobacteriaceae and Salmonella in retail eggs produced in different poultry rearing systems, ii) Enterobacteriaceae species diversity, and iii) antibiotic resistance profile of E. coli isolates. A total of 350 retail eggs produced by four different rearing systems [organic (n= 100), free-range (n= 100), barn (n= 50) and conventional-cage (n=100)] were collected and characterized microbiologically. Out of the 350 eggs tested, the eggshell surface samples were contaminated, with TMAB, TPAB, coliform, E. coli and Enterobacteriaceae at positive percentages of 100%, 100%, 49.1%, 18.6% and 38%, respectively. The positive percentage of coliform, E. coli and Enterobacteriaceae were statistically significant between rearing systems (P<0.05). However, only mean numbers of TMAB were statistically significant between rearing systems (P<0.05). The contamination percent positive crushed eggshell samples, with TMAB, TPAB, coliform, E. coli and Enterobacteriaceae were 100%, 100%, 50%, 33.7% and 42.5%, respectively. Salmonella was detected from only one Enterobacteriaceae isolate obtained from an organic eggshell pool but not from eggshell surfaces or egg yolks. A total of 35 E. coli isolates were recovered from Enterobacteriaceae isolates. Twelve (34.3%) of them exhibited resistance to least one antibiotic tested. The dominant type of resistance was to ampicillin detected in all 12 E. coli isolates. This study provides valuable baseline data of the occurrence of species diversity of Enterobacteriaceae and antibiotic resistant E. coli in retail eggs produced by alternative or conventional-caged rearing methods which can be used for future risk assessments.

Quality of Japanese quail (Coturnix coturnix japonica) eggs after extended refrigerated storage

Commercial Japanese quail ( Coturnix c, japonica) eggs were stored for 0, 30, 60, 90, and 120 d at 4°C to determine the effects of storage on egg quality. Total aerobic microorganisms ( APC ) and yeast and mold ( YM ) were recovered from the same eggs using 3 different methods, including an eggshell surface rinse, eggshell crush rinse, and contents enumeration. Both APC and YM on eggshell surfaces decreased by 87% (0.9 log reduction) from 0 d to 120 d of storage. APC from crushed eggshells ranged from 2.4 to 3.1 log cfu/egg. YM were not detected in crushed eggshells until 120 d of storage where levels were 1.3 log cfu/egg. Aerobic microorganisms were found in contents of eggs stored 30, 60, or 90 d, but no YM were not detected in egg contents. Albumen pH increased from 0 to 30 d of storage (pH 8.91–9.22). Similarly, the largest decrease in albumen height was between 0 (3.9 mm) and 30 d (3.4 mm) before decreasing to 2.5 mm after 120 d storage. Yolk pH also increased with longer storage times, but the most significant increase occurred between 90 and 120 d of storage (0.49 pH unit increase). Similarly, Haugh units ( HU ) decreased with longer storage time, with the most significant changes occurring between 90 and 120 d of storage where HU decreased by 3.7. Overall, quail eggs stored for up to 120 d at 4°C had HU values above 72, placing them at AA grade by USDA standards. Findings may be of commercial interest to quail egg producers as a part of their marketing strategy.

Evaluation of Eggshell as Organic Fertilizer on Sweet Basil

Food waste, for example, eggshell has been piling up on earth through the years. On the other hand, home-gardening has been a trend that encouraged by the government. The focus in this study is to decrease and use the eggshell waste by utilizing it as fertilizer. Eggshell has potential to become fertilizer for plants due to its nutrient content. The eggshell fertilizer used in this study was in liquid/foliar and solid form. The comparison of eggshell fertilizer and commercial fertilizer effectiveness was conducted to see their compatibility in basil’s growth. The chemical analysis was conducted on eggshell tea fertilizer to see the nutrient content. The result from this study shows that eggshell fertilizer in liquid/foliar form is compatible with commercial fertilizer. The compatibility might be achieved due to nutrients, such as nitrogen, potassium and chloride in eggshell tea fertilizer. However, the eggshell fertilizer in liquid form performed better than in its solid form. Further studies could be focusing on the effectiveness of crushed eggshell fertilizer in a more controlled environment. In conclusion, eggshell fertilizer can be used as an alternative for fertilizer in home-gardening due to its compatibility to commercial fertilizer. The result of this study might contribute to reducing food waste, specifically eggshell waste. The result of this study might lead to more utilization of eggshell waste, especially as fertilizer, thus decrease the cost of using commercial fertilizer.

Use of chicken eggshell to improve dietary calcium intake in rural sub-Saharan Africa.

Undernutrition resulting from inadequate access to high‐quality, nutritious food is a widespread issue in sub‐Saharan Africa impacting the health and survival of mothers and their children. Inadequate dietary intake leads to a deficiency in nutrients including calcium, required for growth and physiological functioning. This study investigated the potential of increasing dietary calcium intake by the addition of heat‐treated ground eggshell to locally prepared food. A mixed methods approach of literature review, Delphi expert survey and focus group discussions with women of childbearing age in rural Tanzania, were used to assess the practicality, safety, and acceptability of consumption of ground eggshell. Chicken eggshell has high calcium content (380 mg of calcium/gram) and bioavailability comparable to calcium carbonate (~39%) with 1 g sufficient to provide one half of a sub‐Saharan African adult female's dietary calcium needs. Salmonella was indicated as the most likely threat to human health through eggshell consumption. Experts agreed that eggshells boiled for 10 min when preparing hard‐boiled eggs with a further 20 min cooking of crushed eggshell in staple foods would eliminate identified egg‐associated pathogens. Five focus groups (n = 46) indicated eggshells were perceived as waste. However, there was an indication of general acceptance of the approach and a willingness to consider the incorporation of ground eggshells into their diets. Development of suitable communication methods are required to convey benefits and safe preparation methods. Ground eggshell could be a highly equitable method of increasing calcium intakes across rural sub‐Saharan Africa where calcium intake is low and village poultry ownership common.

Fabrication of Non-Implant 3D Printed Skin

Many bandages tend to be harmful when being removed from the human skin. This is a crucial issue, especially faced by burn victims. When bandages are removed from the burn wound, they tend to be harmful by peeling off the newly formed layer of skin over the burn wound. Such nature causes the patient to endure a longer recovery time with additional pain. The objective of this project is to 3D print artificial skin for the victims of burn wounds by using natural gelation. The main aim for creating the artificial skin will be used in place of the current burn wound treatment techniques of dressing the wounds in bandages. The inner layer of this skin was lined with a natural adhesive, a thin layer of agar-agar, which has been reinforced with crushed eggshells to increase its adhesive strength and durability. The synthesized gel contained non adhesive behavior, yet aids in wound healing abilities. Applying hydrocolloids ensures that the wound is kept cool and the gel also ensures efficient heat transfer. This was done so that less sweating occurs on the patient. Based on the experiments that were conducted, the results conclude that the best ratio of artificial skin layer would be 2:1 of agar gel: crushed eggshells. This golden ratio of gel: crushed eggshells for the longest period of time for attachment on the skin without sweating, is achieved. The skin will be printed using Acrylonitrile-Butadiene-Styrene (ABS). The colour of the skin and the shape of the skin was individually designed for each specific patient. The inner gel has the capabilities of reducing the rehabilitation time, without compromising the comfort of the patient. This approach has the potential to be used as a new method to treat burn wounds..

Substrate influence on aromatic plant growth in extensive green roofs in a Mediterranean climate

Green roofs have been described as technical solutions to overcome urban environmental problems, such as decrease of vegetation and stormwater management. In the present study, two pilot 20 m2 extensive green roofs were implemented in an urban Mediterranean region, at a 1st storey on a warehouse building structure, in order to test the adequacy of different substrates for supporting aromatic plants (Lavandula dentata, Helichrysum italicum, Satureja montana, Thymus caespititius and Thymus pseudolanuginosus). Experimental substrates included expanded clay and granulated cork as main components, supplemented with organic matter and crushed egg shell. A commercial substrate that obeys to FLL guidelines was also tested. Plant growth was assessed and compared within each platform. All experimental substrates proved to be adequate for vegetation growth, with the combination of 70% expanded clay, 15% organic matter and 15% crushed egg shell showing the best results regarding plant establishment and growth over time. Water runoff quality parameters - turbidity, pH, conductivity, NH4 +, NO3 −, PO4 3− - met standard values required for water reuse for non-potable purposes, such as toilet flushing or irrigation. Preliminary qualitative thermographic measurements comparing surface temperature of different plant species and the substrate showed that temperature of vegetation surface was lower than substrate, reinforcing green roofs benefits of lowering air temperature in their surroundings. The present research shows that aromatic vegetation combined with clay substrates are suitable for green roofs located in countries of the Mediterranean region.

Performance of Egg-Shell and Fish-Scale as Adsorbent Materials for Chromium (VI) Removal from Effluents of Tannery Industries in Eastern Uganda

The performance of egg-shells and fish-scales biomaterials in separating chromium (VI) ions from tannery effluents obtained from tannery industries in Jinja town of Eastern Uganda was investigated. Using crushed egg-shell and fish-scales as adsorbents, sorption tests were carried out to determine the effects of bio-sorbent concentration and particle size on chromium (VI) removal. The adsorbate concentration in the tannery effluents before and after adsorption was analyzed using the UV-vis Spectrophotometer at wavelength of 540 nm. The adsorbent concentration was calculated from concentration change in aqueous solution before and after equilibrium sorption. Results showed that chromium (VI) ions adsorb on the surfaces of both biomaterials. The optimum conditions for chromium (VI) removal were found at pH of 6.8, particle size of 300 μm and bio-sorbent concentration of 0.5 g. The correlation coefficient (R2) showed that chromium (VI) adsorption fitted Langmuir adsorption isotherms. It was concluded that the adsorption process of chromium (VI) on the fish-scales and egg-shells was highly feasible.

Higher Storage Temperature Causes Greater Salmonella enterica Serovar Typhimurium Internal Penetration of Artificially Contaminated, Commercially Available, Washed Free Range Eggs

Foodborne salmonellosis is a major public health concern, with contaminated eggs identified as a significant source of infection. In Australia, the most prevalent cause of salmonellosis from eggs is Salmonella enterica subsp. enterica serovar Typhimurium. This study explored the effect of temperature after 1, 7, 14, 21, and 28 days of storage on commercially available washed free range eggs, artificially contaminated with Salmonella Typhimurium on the external surface. At each time point, the external surface of the egg, the crushed eggshell, and the internal egg yolk and albumen were analyzed for Salmonella. After 28 days of storage, 25% of eggs stored at 4°C, 50% of eggs stored at 14°C, and 100% of eggs stored at 23 and 35°C were internally contaminated with Salmonella. After 1 day of storage, more than 50% of all eggs had Salmonella present in the crushed shell after the external surface had been disinfected with ethanol. This is the first study to demonstrate that refrigeration reduced the potential for Salmonella Typhimurium to penetrate the eggshell membrane and internally contaminate table eggs commercially available in Australia. It also suggests that the processes of cracking eggs may be a source of cross-contamination within the kitchen.

Microbiological contamination of shell eggs produced in conventional and free-range housing systems

The present study was conducted to determine microbiological contamination of free-range and conventional chicken eggs produced under controlled conditions. Eighty-four certified Salmonella-free Bovan Brown chicks (age 2 days) were grown in 6 separate floor pens until age 16 weeks, and then moved into 3 conventional battery cages (BC) or 3 free-range (FR) housing systems. Total aerobic microorganisms and Enterobacteriaceae on egg shell surfaces were enumerated weekly when the hens were 20–27 weeks of age (N = 535 and N = 541 for BC and FR, respectively). Prevalence of Salmonella and Campylobacter were determined on crushed egg shells (N = 212 and N = 176, respectively) and in feces (N = 36 and N = 30, respectively) collected from hens at 24 and 28 weeks of age. Counts of total aerobic microorganisms recovered from BC and FR eggs ranged from 5.0 to 6.0 log10 CFU/mL. Numbers of Enterobacteriaceae averaged 1.0 log CFU/mL higher (90% greater) on FR eggs than on eggs from BC hens. Salmonella was not detected on any of the eggs collected from BC hens (0/212), but prevalence on eggs collected from FR hens was 2.36% positive (5/212). Prevalence of Campylobacter recovered from eggs collected from FR (26.1% positive or 46 out of 176 positive) was significantly higher (P ≤ 0.0001) than the prevalence of Campylobacter recovered from eggs from BC hens (7.4% positive or 13 out of 176 positive). These data demonstrate that FR eggs, where hens have more contact with eggs after oviposition, have greater microbiological contamination on the egg shell surface than eggs produced in the BC cage systems.

Poultry egg components as cereal bait additives for enhancing rodenticide based control success and trap index of house rat, Rattus rattus

To compare the acceptance and efficacy of cereal bait containing different concentrations of poultry egg components in laboratory and poultry farms to control house rat, Rattus rattus (R. rattus). Acceptance of cereal bait containing different concentrations (2%, 5% and 10%) of poultry egg components such as egg shell powder (ESP), egg albumin (EA) and crushed egg shell as bait additives were studied after exposing them to different groups of rats in bi-choice with bait without additive. Behaviour of rats towards cereal bait containing 2% concentration of different egg components was recorded in no-choice conditions through Food Scale Consumption Monitor. In poultry farm predominantly infested with R. rattus, acceptance and efficacy of 2% zinc phosphide bait containing 2% EA and ESP was evaluated. Trap success of single rat traps containing chapatti pieces smeared with 2% EA and 2% ESP was also evaluated in poultry farm. In bi-choice tests, significantly (P<0.05) higher preference was observed for baits containing 2% and 5% ESP and all the three concentrations of EA compared to plain bait by female rats and that of baits containing 5% and 10% EA by male rats. In no-choice test, non-significantly higher consumption, number of bouts made and time spent towards bait containing 2% EA was found by rats of both sexes. In poultry farm, acceptance and efficacy of 2% zinc phosphide bait containing 2% EA and ESP was significantly (P<0.05) more than 2% zinc phosphide bait without additive. No significant difference was, however, found in trap success of single rat traps containing chapatti pieces smeared with 2% concentration of EA and ESP placed in the poultry farm. Present data support the use of 2% egg albumin and egg shell powder in cereal bait to enhance acceptance and efficacy of 2% zinc phosphide bait against R. rattus. This may further help in checking the spread of rodent borne diseases to animals and humans.

Separation of chromium(III) and chromium(VI) from environmental water samples using eggshell sorbent

This paper presents the adsorption of Cr(III) and Cr(VI) ions from aqueous solutions and water samples in a laboratory batch scale mode by eggshells as a low-cost sorbent, which is available, cheap, and may represent an environmental problem. The adsorption process and extent of adsorption are dependent on the physical and chemical characteristics of the adsorbent, adsorbate and experimental conditions. The effect of process parameters (i.e., solution pH, initial concentration of Cr(III) ions, sorbent dose, shaking time, temperature, and various ions) on the adsorption of Cr(III) was studied. It was found that crushed eggshells possess relatively high sorption capacity, when comparing with other sorbents. Moreover, the sorption capacity increased with the increase of Cr(III) and sorbent concentrations and temperature. Thermodynamic parameters viz. the change in Gibbs free energy change (∆Gº ), enthalpy (∆Hº ) and entropy (∆Sº ) were also calculated. These parameters indicated that the adsorption process of chromium(III) on eggshell sorbent was spontaneous and endothermic in nature. Under the optimum experimental conditions employed, the removal of ca. ~100% of Cr(III) and Cr(VI) ions in a mixture (1:1), after reduction of Cr(VI) to Cr(III), was attained. The procedure was successfully applied to remove chromium ions from aqueous and different natural water samples. Keywords: Chromium(III), chromium(VI), sorption, eggshells, low-cost sorbent, water samples.

Separation of Chromium(III) and Chromium(VI) from Environmental Water Samples Using Eggshell Sorbent

This paper presents the adsorption of Cr(III) and Cr(VI) ions from aqueous solutions and water samples in a laboratory batch scale mode by eggshells as a low-cost sorbent, which is available, cheap, and may represent an environmental problem. The adsorption process and extent of adsorption are dependent on the physical and chemical characteristics of the adsorbent, adsorbate and experimental conditions. The effect of process parameters (i.e., solution pH, initial concentration of Cr(III) ions, sorbent dose, shaking time, temperature, and various ions) on the adsorption of Cr(III) was studied. It was found that crushed eggshells possess relatively high sorption capacity, when comparing with other sorbents. Moreover, the sorption capacity increased with the increase of Cr(III) and sorbent concentrations and temperature. Thermodynamic parameters viz. the change in Gibbs free energy change (ΔG ° ), enthalpy (ΔH ° ) and entropy (ΔS ° ) were also calculated. These parameters indicated that the adsorption process of chromium(III) on eggshell sorbent was spontaneous and endothermic in nature. Under the optimum experimental conditions employed, the removal of ca. ~100% of Cr(III) and Cr(VI) ions in a mixture (1:1), after reduction of Cr(VI) to Cr(III), was attained. The procedure was successfully applied to remove chromium ions from aqueous and different natural water samples.

Biosorption of Cr(III) ions by eggshells

The paper presents results of studies carried out on sorption of Cr(III) ions from aqueous solutions by eggshells as a low-cost sorbent. It was found that crushed eggshells posses relatively high sorption capacity, when comparing with other sorbents, that was evaluated as 21–160 mg/g. The effect of process parameters: pH, temperature, initial concentration of Cr(III) ions on the process kinetics was studied. It was found that the equilibrium of the process was reached after 60 min. Also equilibrium studies were performed: the effect of sorbent concentration and equilibrium Cr(III) concentration was studied. The maximum experimentally determined sorption capacity 160 mg/g was obtained at low sorbent concentration at 20 °C and pH 5. It was found that sorption capacity increased with the increase of Cr(III) concentration, temperature and sorbent concentration. Mathematical models describing kinetics and equilibrium of sorption were proposed. The process kinetics was described with pseudo-second-order pattern and equilibrium was described with Langmuir-type equation, and the influence of sorbate concentration, with an empirical dependence. The models were positively verified. Eggshells were able to remove the concentration of Cr(III) ions below the acceptable level, i.e. at 40 °C, at the initial concentration of metal ions 100 mg/kg, at sorbent concentration 15 g/l.

Effects of Hen Egg Shell and Other Calcium Sources Upon Egg Shell Strength and Ultrastructure

The suitability of egg shell as a calcium source in layer diets was examined by comparing pulverized and crushed sterilized egg shells against oyster shell, limestone grit, and pulverized limestone, as calcium supplements. These calcium sources were fed in appropriate amounts to obtain diets with 3% total calcium. Breaking strength of the eggs, determined at 90 and 150 days of feeding, showed that eggs from the hens fed the diets containing oyster shell, pulverized egg shell and limestone grit were significantly stronger (P<0.01) than eggs from hens fed diets containing pulverized limestone as the calcium source. Crushed egg shells as a dietary source of supplemental calcium promoted egg shell quality equivalent to that obtained with pulverized limestone. The results of a second experiment indicated that oyster shell produces a greater improvement in the shell quality of the second, third and subsequent eggs in the clutch than it does upon the first egg in the clutch. These results indicated that the presence of particles of calcium carbonate in the diet are more important for hens in very high production than for those in low egg production.Scanning electron micrographs revealed that most of the changes responsible for differences in shell breaking strength apparently take place in the palisade layer, while the mammillary layer remains approximately constant. It appeared that the palisade layer contributes most of the strength in the shell. As the palisade layer decreased in thickness and in concentration, there was a closely predictable decrease in breaking strength of the eggs. Evidence was obtained indicating a poor correlation between breaking strength and total shell thickness. Breaking strength is a superior measure of egg shell quality because it takes into consideration both the thickness and the concentration of the palisade layer around the crystalline mammillary portion of the egg shell.