Effects of different pretreatment methods on sludge inoculum were evaluated concerning hydrogen (H2) production enhancement and COD (chemical oxygen demand) reduction, using domestic effluent in a batch system. The sludge was taken from a recycled line of the activated sludge reactor. Two types of pretreatment were investigated, heat treatment and chloroform treatment. The experiment was conducted at pH 4-6 and inoculum sizes of microbes were 10%, 20%, and 30% respectively; and experiment without sludge pretreatment was also conducted as control. The result showed that 30% COD reduction was achieved for chloroform pretreatment at pH 3 and 10% inoculum size. For heat treatment, a maximum COD removal of 60% was achieved in the experiment at pH 6 and 10% inoculum size. In chloroform pretreatment, a maximum volume of gas evolved was 3.6 mL, at pH 3 and 20% inoculum size. For heat pretreatment, maximum biogas evolved was 2.1 mL, at pH 3 and 10% inoculum size. The experimental results showed that the pretreatment methods (heat treatment and chloroform treatment) at 35 °C and initial pH 5.5 had a positive influence on H2 production yield and COD removal efficiency during the fermentative H2 production as compared to the control experiments (without pretreatment). Heat treatment method was shown to be a simple and useful method for enhancing both H2 producing and COD removal processes from domestic effluent with highest H2 yield and COD removal efficiency at 0.314 mmol H2/g COD and 86%, respectively.
This research aims to investigate the ability of biosand filter to remove organic pollutants from laboratory wastewater. Biosand filter is a simple treatment using fine sand, coarse sand and gravel media. In the biosand filter, the biofilm growth occurs on the top surface of the media. The observed parameter for organic content was BOD and COD. The media in the biosand filter reactor were fine sand: coarse sand: gravel with a depth ratio of 50: 5: 5 cm. The biofilm growing process was carried out for 15 days by immersing the media with samples. The substrate was added to the reactor in the 10th day to accelerate biofilm growth. During the growth of the biofilm, the dissolved oxygen (DO), pH and temperature were also observed. After the biofilm growth, the biosand filter was operated intermittently for 14 days, which is an hour operation and a pause period of 47 hours, repeatedly until 29 days. The applied flow rate was 0.6 L / min. The results showed that BOD removal efficiency was 76.9%, and COD removal efficiency was 73.5%. The biosand filter reduced BOD concentration from 161.5 mg/L to 36.1 mg/L and reduced COD concentration from 202.4 mg/L to 52.8 mg/L.
Samples of limestone composites were measured for hardness in 5 difference colors: black, dark blue, blue, light blue and white. Limestone was then ground and particle sizes of meal were measured. The meal were mixed with other locally available materials to produce 5 difference mineral formulas: P1: 100% limestone meal, P2: 50% limestone meal + 50% fresh water oyster shell meal, P3: 35% limestone meal + 30% fresh water oyster shell meal + 35% bone meal, P4: 35% limestone meal + 30% fresh water oyster shell meal + 34.2% bone meal + 0.5% salt + 0.3% micro minerals and P5: 100% fresh water oyster shell meal. The formulas were stored for 12 weeks. Samples were taken weekly for analyzing of moisture content and physical properties. By a feeding trial the five mineral formulas were mixed in the level of 6 % into basal diet and fed to 150 laying hens for 24 weeks. Parameters measured included body weight, feed intake, egg production and FCR. Results showed that the composites of Bukit Kamangs' limestone had difference hardness. The strongest was found by the black composite of 23.4 HRc-C or 245.0 BHN. The meal products contained large particles (>0.42 mm) of 17.8%. Moisture content of mineral formulas increased during storage, but their physical properties were no significant changes. The highest moisture increase was found by the product of 100% limestone, but it could be reduced by mixing with oyster shell meal and bone meal. The best laying performances (P<0.05) were found by the hens fed with diet supplemented with mineral formula containing limestone, fresh water oyster shell and fortified with micro minerals.
This study analyzes the environmental impact of 1 ton green tea 50 gr canned in x company using the Life Cycle Assessment (LCA) method. A cradle to gate approach was used to scope the study, from plantations to packaging. SimaPro version 9 software is used as a tool for assessing LCA. The evaluation step refers to ISO 14044 of 2006, which determines the objectives and scope, inventory analysis, impact, and interpretation. The method used to assess the environmental impacts is the CML-IA Baseline. The classification results of the dominant and significant impact characterization on the environment are global warming with 475.557,7 kg CO2 eq. Drying process II, drying process I, PLN electricity, and transportation contribute to the environmental impact. The recommendation for technical improvement based on the sensitivity analysis results is using PLN electricity with renewable energy, namely micro hydro (PLTMH). The combination of wood biomass with other biomass is rice husks, then changing the truck fuel from diesel to fuel that is morm e environmentally friendly Pertamina Dex.
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