Spent coffee ground-based interfacial solar steam generation

Journal of Material Cycles and Waste Management - In this work, for the first time, spent coffee grounds (SCGs) were utilized for photothermal conversion. SCG-coated filter paper was obtained by a...     

Characterizations of biochar from hydrothermal carbonization of exhausted coffee residue

The aim of this study was to produce renewable energy from exhausted coffee residue, which is a form of biomass. As coffee preference continues to increase, the importation of coffee beans has been increasing sharply. However, the amount of coffee that is actually consumed is only about 0.2% of coffee beans, while the spent coffee beans are discarded in the form of exhausted coffee residue. Hydrothermal carbonization is a method of producing an improved fuel from renewable energy sources by changing the physical and chemical properties of biochars. Biochars were obtained from a variety of reaction temperatures during hydrothermal carbonization and analyzed using elemental analysis, ultimate analysis, and calorific value measurement. The atomic C/O and C/H ratios of all obtained biochars decreased and were found to be similar to those of lignite and sub-bituminous coal. The highest energy recovery efficiency of biochar indicates that the optimum reaction temperature for hydrothermal carbonization was between 210 and 240 °C, which produced biochars with calorific value of approximately 26–27 MJ/kg. The spectra of biochars obtained from Fourier transform infrared spectroscopy (FTIR) showed fewer C–O and aliphatic C–H functional groups, but more carbonyl C=O functional groups and aliphatic CH _x groups. The results of this study indicate that hydrothermal carbonization can be used as an effective means to generate highly energy-efficient renewable fuel resources from coffee residue. The thermogravimetric analysis provided the changing combustion characteristics due to increased fixed carbon content.     

The application and evaluation research of coffee residue ash into mortar

Coffee residue is usually regarded as a kind of agriculture waste; as its quantity increases the treatment of coffee residue will become an environmental problem. This research is innovative in that it derives the possibility of recycle application using coffee residue ash for cement replacement. In this research, coffee residue is burned in an electronic oven to three kinds of coffee residue ash at 500, 600 and 700 °C, and then appropriate apparatus is used to check the chemical and physical properties of these three types of coffee residue ash. After a general comparison, this study selected 500 and 600 °C coffee residue ashes with 2, 3, 5, 10 and 15 % cement replacements to make 5 cm³ cube mortar specimen to test different curing ages’ compressive strength. Through measurement and experiment, this research found that the compressive strength decreased by adding 500 or 600 °C coffee residue ash into the mortar. By considering waste reduction and practice application, this research derives that using the 600 °C coffee residue ash with 10 % replacement is better than others application, such using result also can get valuable efficiencies of financial and CO₂ reduction.     

Development and Application of Green Composites: Using Coffee Ground and Bamboo Flour

Environmental degradation and global warming are increasing as a result of the use of petroleum. Therefore, many industries are seeking more eco-friendly materials that will decrease the level of environmental contamination and economic cost. Recently, the level of coffee consumption has increased rapidly. Therefore, the amount of coffee grounds discarded is increasing. In this study, polylactic acid, coffee grounds and bamboo flour were compounded for green composites. Coffee grounds are used in the recycling of food waste. In addition, 4,4-methylene diphenyl diisocyanate (MDI) was used as a coupling agent. The mechanical strength of green composites decreased with increasing natural filler content. However, mechanical and thermal properties were increased by the addition of MDI as a coupling agent. The hydroxyl groups of natural fillers reacted with the isocyanate group of MDI, and a urethane linkage was created between the polymer and natural fillers.     

Vapor intrusion mitigation challenges posed by a classic urban setting

AECOM's Environmental Remediation Services Group, under a Pennsylvania Department of Environmental Protection (PADEP) remediation contract, was tasked with assessing potential vapor intrusion risks and mitigating identified risks at an active commercial property affected by a former adjacent laundry and dry cleaning operation. The former dry cleaning operation was positioned in the center of row‐buildings containing various commercial businesses. The neighboring active commercial property is an antiquated building that operates as a coffee shop. The coffee shop building contains a service area, a kitchen, and a rear conference room on the first floor, a storage area on the second floor, and a partial basement. The basement has been observed to periodically flood. Adjacent to the coffee shop building is an operating hair and nail salon that formerly functioned as one of the dry cleaning operations buildings with known soil, groundwater, and soil gas impacts. Due to the disposition of the coffee shop building, a methodical approach was implemented to characterize the potential vapor intrusion risk and included a diagnostic building inspection that identified required management of basement apertures and abatement of periodic flooding prior to vapor intrusion mitigation system design and installation.     

Polyvinyl Alcohol (PVA)/Starch Bioactive Packaging Film Enriched with Antioxidants from Spent Coffee Ground and Citric Acid

The bioactive packaging polyvinyl alcohol (PVA)/starch films were prepared by incorporating combined antioxidant agents i.e. extracted spent coffee ground (ex-SCG) and citric acid. Effect of citric acid content on chemical compatibility, releasing of antioxidant, antibacterial activities, and physical and mechanical properties of PVA/starch incorporated ex-SCG (PSt-E) films was studied. The results of ATR-FTIR spectra showed that antioxidant agents of ex-SCG can penetrate into the film and the ester bond of blended films by citric acid was also observed. The presence of ex-SCG increased efficiency of antioxidant release and antimicrobial activity. The PSt-E film incorporated 30 wt% citric acid showed minimum inhibitory concentration against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The incorporation of ex-SCG and citric acid into film showed a synergistic effect on antibacterial activity. The water resistance and kinetic moisture sorption improved with incorporation of citric acid. The tensile strength and biodegradability of samples were in range of 5.63–7.44 MPa and 65.28–86.64%, respectively. Based on this study, PSt-E film incorporated 30 wt% citric acid can be applied as novel food packaging materials.     

Comparative Life Cycle Assessment of Coffee Capsule Recycling Process and Its Composites Reinforced with Natural Fibers

Journal of Polymers and the Environment - The present research aims to propose a comparative life cycle assessment (LCA) between the coffee capsules recycling process and the process of obtaining...     

Fenton试剂氧化法处理染料结晶废母液

采用Fenton试剂氧化法处理分散橙、分散紫和分散蓝3种染料结晶废母液。研究了H₂O₂加入量、n（H₂O₂）#x02236;n（Fe²⁺）和废母液pH对COD去除率或TOC去除率的影响。对TOC去除反应分段进行了动力学方程拟合,并探讨了反应机理。实验得到的分散橙、分散紫和分散蓝的废母液处理工艺条件：H₂O₂加入量分别为264.4,352.9,441.2mmol/L;n（H₂O₂）#x02236;n（Fe²⁺）分别为20,10,20;废母液pH=3。3种废母液在0~20min和20~120min两个阶段的反应与二级动力学拟合方程的相关性最好。3种废母液经Fenton试剂氧化处理后,部分有机物降解为小分子有机酸,部分有机物完全矿化。     

Coffee husk composting: An investigation of the process using molecular and non-molecular tools

Various parameters were measured during a 90-day composting process of coffee husk with cow dung (Pile 1), with fruit/vegetable wastes (Pile 2) and coffee husk alone (Pile 3). Samples were collected on days 0, 32 and 90 for chemical and microbiological analyses. C/N ratios of Piles 1 and 2 decreased significantly over the 90 days. The highest bacterial counts at the start of the process and highest actinobacterial counts at the end of the process (Piles 1 and 2) indicated microbial succession with concomitant production of compost relevant enzymes. Denaturing gradient gel electrophoresis of rDNA and COMPOCHIP microarray analysis indicated distinctive community shifts during the composting process, with day 0 samples clustering separately from the 32 and 90-day samples. This study, using a multi-parameter approach, has revealed differences in quality and species diversity of the three composts.     

Sustainable Use of Coffee Husks For Reinforcing Polyethylene Composites

The utilization of the coffee husk fiber (CHF) from the coffee industry as a reinforcing filler in the preparation of a cost-effective thermoplastic based composite was explored in this study. The chemical composition and thermal properties of the CHF were investigated and compared with those of wood fiber (WF). CHF proved to be mainly composed of cellulose, hemicellulose and lignin, and exhibited similar thermal behavior to WF. High density polyethylene (HDPE) composites with CHF loadings of from 40 to 70% were prepared using melt processing and extrusion. The processing properties, mechanical behavior, water absorption and thermal performance of these composites were investigated. The effect of maleated polyethylene (MAPE) used as a coupling agent on the composite was explored. The experimental results showed that increasing the CHF loading in the HDPE matrix resulted in an increase in the modulus and thermal properties of the composites, but resulted in poor water resistance. The addition of a 4% MAPE significantly improved the interfacial behavior of the hydrophilic lignocellulosic fiber and the hydrophobic polymer matrix.     

Characterization and recovery of mercury from spent fluorescent lamps

Fluorescent lamps rely on mercury as the source of ultraviolet radiation for the production of visible light. Partitioning of mercury among vapor phase, loose phosphor powders produced during breaking and washing steps, glass matrices, phosphor powders attached on the glass and aluminum end caps was examined from simulated laboratory lamp recycling tests for different types of spent and new fluorescent lamps. Mercury concentrations in lamp glasses taken from commercial lamp recyclers were also analyzed for comparison with the simulated results of spent and new lamps of different types. The mercury content of the glass from spent lamps was highly variable depending on the lamp type and manufacturer; the median values of the mercury concentration in glasses for spent 26- (T8) and 38-mm (T12) diameter fluorescent lamps were approximately 30 and 45 microg/g, respectively. The average mercury concentration of samples taken from recycler A was 29.6 microg/g, which was about 64% of median value measured from the spent T12 lamps. Over 94% of total mercury in lamps remained either as a component of phosphor powders attached inside the lamp or in glass matrices. New T12 lamps had a higher partitioning percentage of elemental mercury in the vapor phase (0.17%) than spent T12 lamps (0.04%), while spent lamps had higher partitioning percentages of mercury resided on end-caps and phosphor powders detached from the breaking and washing steps. The TCLP values of simulated all lamp-glasses and samples obtained from recyclers were higher than the limit of LDR standard (0.025 mg/L). After investigating acid treatment and high temperature treatment as mercury reclamation techniques, it was found that heating provided the most effective mercury capture. Although the initial mercury concentrations of individual sample were different, the mercury concentrations after 1 h exposure at 100 degrees C were below 4 mug/g for all samples (i.e., <1% remaining). Therefore, it is recommended that heating be used for recovering mercury from spent fluorescent lamps.     

Isolation and identification of potential fungal species for spent engine lubrication oil remediation in Peninsular Malaysia

Improper disposal and spills of spent engine oil into the environment can result in contamination, which eventually affects humans through the food chain. Mycoremediation is an effective and inexpensive alternative to clean up spent engine oil contamination. In recent work, the potential effectiveness of fungi for degrading spent engine oil was confirmed, with the species identified through molecular identification. Fungi that were able to grow in Bushnell Haas Broth supplied with spent engine oil were identified with the potential to utilize spent engine oil as a carbon source. Six species of fungi namely Penicillium simplicissimum, Aspergillus nidulans, Aspergillus niger, Trichoderma longibrachiatum, Aspergillus ustus, and Aspergillus flavus were successfully identified in this study. Over a course of seven days, P. simplicissimum (21.11 percent) was identified as the most effective fungi in degrading spent engine oil, followed by A. nidulans (17.75 percent), A. niger (15.85 percent), T. longibrachiatum (15.12 percent), A. ustus (15.02 percent), and A. flavus (11.80 percent). As these species of fungi were isolated from the natural environment in Peninsular Malaysia, the potential of using these fungi as mycoremediation of spent engine oil was therefore confirmed.     

溶剂萃取法提取废旧碱性电池中的有价成分

为回收利用废旧电池，进行了溶剂萃取法提取碱性废弃电池中锌、锰金属的试验研究。选择南孚（AA）碱性废电池为处理样品，通过粉碎、水浸、酸浸等步骤，获得含锌、锰离子的稀溶液，并利用模拟体系得到的萃取结果进行浸出液的萃取性能试验研究。结果表明，每个废电池填充物中含锌和锰分别为0.25g和0.36g，具有可观的回收价值；采用完全皂化的二（2－乙基己基）磷酸（D2EHPA）／煤油为萃取剂提取含锌锰的酸浸出液，一级萃取就可获得60％以上的提取率。     

Enzymatic pretreatment of lignocellulosic wastes to improve biogas production

The effect of enzymatic pretreatment of sugar beet pulp and spent hops prior to methane fermentation was determined in this study. These industrial residues were subjected to enzymatic digestion before anaerobic fermentation because of high fiber content (of 85.1% dry matter (DM) and 57.7% DM in sugar beet pulp and spent hops, respectively). Their 24h hydrolysis with a mix of enzymatic preparations Celustar XL and Agropect pomace (3:1, v/v), with endoglucanase, xylanase and pectinase activities, was most effective. Reducing sugars concentrations in hydrolysates of sugar beet pulp and spent hops were by 88.9% and 59.4% higher compared to undigested materials. The highest yield of biogas was obtained from the enzymatic hydrolysate of sugar beet pulp (183.39 mL/d from 1g COD at fermenter loading with organic matter of 5.43 g COD/L × d). Fermentation of sugar beet pulp gave 19% less biogas. Methane fermentation of spent hops hydrolysate yielded 121.47 mL/d biogas from 1g COD (at 6.02 g COD/L × d, 13% more than from spent hops). These results provide evidence that suitable enzymatic pretreatment of lignocellulosic wastes improve biogas yield from anaerobic fermentation.     

Analytical determination of the suitability of different processes for the treatment of odorous waste gas

In order to determine the efficiency of different treatment systems for the reduction of odorous emissions, a gas chromatographic method followed by simultaneous mass spectrometry and olfactometry (GC-MS/O) was developed. Samples from a coffee bean roasting and a fat and oil processing plant were analyzed, respectively. The results were compared with the data obtained by olfactometric measurements. At a coffee bean roasting plant, cooling gases were analyzed prior to and after treatment in a full scale bioscrubber. The GC-MS/O analysis showed that the amounts of aldehydes and ketones decreased after treatment of cooling gases of coffee bean roasting in the bioscrubber, whereas the contents of the heterocyclic compounds, like pyridine and the pyrazines, and acetophenone and guaiacol remained almost unchanged. The amounts of dimethyl disulfide, 3-hydroxy-2-butanone, and the carboxylic acids increased after bioscrubber treatment. Furthermore, the performance of each stage of a combined experimental plant for the treatment of exhaust air of fat and oil processing was investigated. This treatment plant consisted of a bioscrubber, a biofilter, and an activated carbon adsorber. The important odor-active compounds of the exhaust air of fat and oil processing were the typical fat oxidation products (aldehydes, ketones) and with lower importance 2-pentylfuran, a few terpenes and aromates. Again, the key odor-active compounds, aldehydes and ketones, were degraded in the bioscrubber. Further degradation of aliphatic, unsaturated, methylated, and cyclic alkanes, as well as aromates, terpenes, and furans by the biofilter was observed. After the last treatment stage, the activated carbon filter, only small amounts of aliphatic, unsaturated, methylated, and cyclic alkanes and aromates remained in the waste gas. For both applications, the results of the developed GC-MS/O method correlated very well with olfactometric measurements.     

Bioleaching of metals from spent lithium ion secondary batteries using Acidithiobacillus ferrooxidans

Bioleaching of spent lithium ion secondary batteries, containing LiCoO2, was attempted in this investigation. The present study was carried out using chemolithotrophic and acidophilic bacteria Acidithiobacillus ferrooxidans, which utilized elemental sulfur and ferrous ion as the energy source to produce metabolites like sulfuric acids and ferric ion in the leaching medium. These metabolites helped dissolve metals from spent batteries. Bio-dissolution of cobalt was found to be faster than lithium. The effect of initial Fe(II) concentration, initial pH and solid/liquid (w/v) ratio during bioleaching of spent battery wastes were studied in detail. Higher Fe(II) concentration showed a decrease in dissolution due co-precipitation of Fe(III) with the metals in the residues. The higher solid/liquid ratio (w/v) also affected the metal dissolution by arresting the cell growth due to increased metal concentration in the waste sample. An EDXA mapping was carried out to compare the solubility of both cobalt and lithium, and the slow dissolution rate was clearly found from the figures.     

废催化裂化催化剂的危险性及污染特征

为考察我国废催化裂化(FCC)催化剂的危险性及污染特征,以国内典型FCC装置的废催化剂为研究对象,分析其易燃性、反应性、腐蚀性、浸出毒性、毒性物质含量及急性毒性。研究发现:废FCC催化剂无易燃性、反应性、腐蚀性、急性毒性危险;未检测出具有致癌致突变性的有机污染物;废FCC催化剂的特征污染物为Ni及其化合物,Ni的浸出浓度低于国家标准限值,Ni的存在形态为Ni Al2O4尖晶石,而非具有致癌性的Ni O形态。     

Organic oxalate as leachant and precipitant for the recovery of valuable metals from spent lithium-ion batteries

Spent lithium-ion batteries containing lots of strategic resources such as cobalt and lithium are considered as an attractive secondary resource. In this work, an environmentally compatible process based on vacuum pyrolysis, oxalate leaching and precipitation is applied to recover cobalt and lithium from spent lithium-ion batteries. Oxalate is introduced as leaching reagent meanwhile as precipitant which leaches and precipitates cobalt from LiCoO(2) and CoO directly as CoC(2)O(4)·2H(2)O with 1.0 M oxalate solution at 80°C and solid/liquid ratio of 50 g L(-1) for 120 min. The reaction efficiency of more than 98% of LiCoO(2) can be achieved and cobalt and lithium can also be separated efficiently during the hydrometallurgical process. The combined process is simple and adequate for the recovery of valuable metals from spent lithium-ion batteries.     

Chemical and physical characterization of electrode materials of spent sealed Ni-Cd batteries

The present work aimed at the chemical and physical characterization of spent sealed MONO-type Ni-Cd batteries, contributing to a better definition of the recycling process of these spent products. The electrode material containing essentially nickel, cadmium and some cobalt corresponds to approximately 49% of the weight of the batteries. The remaining components are the steel parts from the external case and the supporting grids (40%) containing Fe and Ni, the electrolyte (9%) and the plastic components (2%). Elemental quantitative analysis showed that the electrodes are highly concentrated in metals. The phase identification achieved by X-ray powder diffraction combined with chemical analysis and leaching tests allowed the authors to proceed with the composition of the electrode materials as following: cathode: 28.7% metallic Ni, 53.3% Ni(OH)2, 6.8% Cd(OH)2 and 2.8% Co(OH)2; anode: 39.4% metallic Ni and 57.0% Cd(OH)2. The morphology of the electrodes was studied by microscopic techniques and two phases were observed in the electrodes: (1) a bright metallic phase constituted of small nickel grains that acts as conductor, and (2) the main hydroxide phase of the active electrodes into which the nickel grains are dispersed. The disaggregation of the electrode particles from the supporting plates was easily obtained during the dismantling procedures, indicating that a substantial percentage of the electrodes can be efficiently separated by wet sieving after shredding the spent batteries.     

Assessment of the use of spent copper slag for land reclamation.

The shortage of waste landfill space for waste disposal and the high demand for fill materials for land reclamation projects in Singapore have prompted a study on the feasibility of using spent copper slag as fill material in land reclamation. The physical and geotechnical properties of the spent copper slag were first assessed by laboratory tests, including hydraulic conductivity and shear strength tests. The physical and geotechnical properties were compared with those of conventional fill materials such as sands. The potential environmental impacts associated with the use of the spent copper slag for land reclamation were also evaluated by conducting laboratory tests including pH and Eh measurements, batch-leaching tests, acid neutralization capacity determination, and monitoring of long-term dissolution of the material. The spent copper slag was slightly alkaline, with pH 8.4 at a solid : water ratio of 1 : 1. The batch-leaching test results show that the concentrations of the regulated heavy metals leached from the material at pH 5.0 were significantly lower than the maximum concentrations for their toxicity limits referred by US EPA's Toxicity Characteristic Leaching Procedure (TCLP). It was also found that the material is unlikely to cause significant change in the redox condition of the subsurface environment over a long-term period. In terms of physical and geotechnical properties, the spent copper slag is a good fill material. In general, the spent copper slag is suitable to be used as a fill material for land reclamation.