Biological recycling of used baby diapers in a small-scale composting system

Ünlü

Int J Recycl Org Waste Agricult

2016

Purpose In waters and wastes, direct pathogen detection is difficult and time consuming. Therefore, coliforms are used as indicators to measure the presence of pathogens. Composts originated from extrements, sewage sludges and plant wastes those contact with manures may have potential health hazard to human. Therefore, the detection of coliforms both during composting and in the obtained composts is used to investigate the presence of pathogens for determination of the potential health risk. Methods In this study, the effect of six different aeration rates on elimination of total and faecal coliform bacteria was investigated during in-vessel aerobic composting of vegetable-fruit wastes. Total coliform and faecal coliform numbers in the samples were measured by the most probable number method. Results Coliforms significantly increased before the thermophilic stage except the faecal coliforms in the reactor which operated with the lowest aeration. The coliforms suddenly decreased after thermophilic stage in all reactors. Total coliforms reduced within the range of 78.2-99.9 % while faecal coliforms reduced within the range of 72.5-99.9 % after the thermophilic stage. At the end of the composting period (day 18), total coliforms and faecal coliforms reduced within the range of 99.9-100 %. Conclusions Although all the aeration rates used in the present study were effective for the elimination of coliforms, the lowest faecal coliform number was seen in the reactor that had the lowest aeration rate. At the end of the study, the faecal coliform numbers in all reactors confirmed some limits for the application activities of composts.

Section: Resultsmentioning

confidence: 99%

Effect of aeration rate on elimination of coliforms during composting of vegetable–fruit wastes

Ünlü

Int J Recycl Org Waste Agricult

2016

J of Chemical Tech & Biotech

“…Interestingly, WDD contain nearly 35% of cellulose, which is degradable under biological conditions (i.e. anaerobic degradation and composting). Other components of WDD are plastic materials, notably polyethylene, polypropylene and a super water‐absorbent sodium polyacrylate (SPA); on a dry basis, diapers contain c .…”

Section: Introductionmentioning

confidence: 99%

Sodium polyacrylate inhibits fermentative hydrogen production from waste diaper‐like material

Sotelo-Navarro

Poggi‐Varaldo

Turpin-Marion

et al. 2019

BACKGROUND: The inhibitory effect of a moisture-absorbent sodium polyacrylate (SPA), that is commonly used in disposable diapers, on the bio-hydrogen (H 2 ) generation from waste diaper-like material (WDM) was assessed in dark fermentation studies. Three types of treatments were evaluated in batch bioreactors at 37 ∘ C: mixture of bond paper and filter paper (WDM, no SPA), SPA alone (only SPA or control), and WDM spiked with SPA [paper plus sodium polyacrylate hydrogel (WDM-SPA)]. The WDM simulated the cellulosic fraction of diaper composition. RESULTS:The units with only SPA did not produce H 2 . The WDM-SPA units exhibited H 2 production 25% lower than those of bioreactors loaded with only WDM but no SPA. Cumulative H 2 production was 0.03, 4.22 and 5.50 mmolH 2 g TS -1 for the SPA, WDM-SPA and WDM reactors, respectively (0.04, 5.90 and 8.77 mmolH 2 g VS -1 ; 0.89, 132.19 and 196.45 NmLH 2 g VS -1 ). BioH 2 generation was related to predominance of the fermentation route that produces 1 mol L -1 of butyric acid (HBu) plus 2 mol L -1 H 2 in the WDM and WDM-SPA units, as suggested by the ratio A:B (acetic: butyric acids; A:B < 0.79 mg HAc-COD mg HBu-COD -1 in both cases).CONCLUSION: It seems that this is the first documented result on the inhibitory effect of SPA on the bioH2 fermentation of cellulosic wastes. However, further research should be carried out at different levels of SPA to determine, for instance, the half-inhibition value of SPA, that is, the concentration of SPA that would cause a 50% drop in H 2 generation of the non-SPA treatment.

“…At present, used baby diapers are not recycled and dump in the landfills which representing about 4% of municipal solid waste [4]. Impact associated to disposal of diapers landfilling include land use, methane production and leaching of organic compounds to soil and groundwater and combustion of diapers could lead to production of contaminants of carbon dioxide and chlorine compounds [5].…”

Section: Introductionmentioning

confidence: 99%

Properties of Self-curing High Strength Concrete by using Baby Polymer Diapers

et al. 2018

This study investigates the self-curing concrete using baby polymer diapers as substitute method of curing process in order to improve mechanical and physical properties of concrete. Three different proportion of baby polymer diapers which are 1%, 3% and 5% were mix with concrete. Slump, compressive strength and drying shrinkage test were performed in order to study the workability, strength and durability of the concrete. All concrete were tested for 1, 3, 7, 14, and 28 days for drying shrinkage test. Meanwhile, all concrete were test at 3, 7 and 28 days for compressive strength test. Compressive strength of concrete containing 5% baby polymer diapers show the highest strength at 28 days compared to others percentage. Thus, it indicates that application of baby polymer diaper as self-cure agent can improve the concrete performances.