PENGARUH PENAMBAHAN BIOAKTIVATOR EM-4 TERHADAP PRODUKSI BIOGAS DARI LIMBAH CAIR INDUSTRI TAHU

Tofu industrial waste is generally divided into two forms of waste, namely solid waste and liquid waste. The liquid waste of the tofu industry contains organic material that can be decomposed anaerobically into methane gas (CH4), other gases, and water which is commonly called biogas. One of the potential biocatalysts as a source of microorganisms in biogas production is Effective Microorganisms 4 (EM-4). This research was conducted by adding EM-4 with a concentration of 0.5%; 1%; and without EM-4 into 15 liters of tofu liquid waste in the digester for fermentation for 7 days. Observation of the pressure on the manometer seen from the difference in the height of the liquid manometer U and the combustion process was carried out on the 7th day (constant pressure). The maximum pressure of biogas for 7 days at 1% EM4 of 927,864 kg/m.s2 produces a blue flame, has an unpleasant odor, does not cause smoke with a fire height of 12,602 mm. So it can be concluded that the greater concentration of EM-4 used, the greater the pressure of biogas and fire

Low-perchlorate blue-flame pyrotechnic compositions

An ammonium perchlorate (AP) and copper(II) benzoate pyrotechnic blue-flame composition was gradually “diluted” by adding an experimental perchlorate-free blue-flame composition based on aminoguanidinium nitrate (AGN), malachite, PVC powder and shellac resin. Flame’s luminous intensity and specific luminous intensity were recorded and analyzed. A copper-aminoguanidinium (CuAG) complex was also synthesized and tested as an energetic additive in perchlorate-free blue-flame composition. Green-flame color was observed when testing chlorine-free energetic compositions with CuAG.

The structure of the blue whirl revealed

The blue whirl is a small, stable, spinning blue flame that evolved spontaneously in recent laboratory experiments while studying turbulent, sooty fire whirls. It burns a range of different liquid hydrocarbon fuels cleanly with no soot production, presenting a previously unknown potential way for low-emission combustion. Here, we use numerical simulations to present the flame and flow structure of the blue whirl. These simulations show that the blue whirl is composed of three different flames—a diffusion flame and premixed rich and lean flames—all of which meet in a fourth structure, a triple flame that appears as a whirling blue ring. The results also show that the flow structure emerges as the result of vortex breakdown, a fluid instability that occurs in swirling flows. These simulations are a critical step forward in understanding how to use this previously unknown form of clean combustion.

PRODUKSI BIOGAS DARI SUBSTRAT DASAR KOTORAN SAPI, KOTORAN AYAM DAN LIMBAH CAIR TAHU DENGAN INOKULUM RUMEN SAPI

The research of biogas aims to obtain an alternative energy source which might replace fossil energy in the future. It was carried out starting from November 2017 to February 2018 in which was located in Langaleso Village, Dolo Subdistrict, Sigi District and in the Laboratory of Biotechnology, Department of Biology, Faculty of Mathematics and Natural Sciences, Tadulako University. The primary substrates were cow dung, chicken manure and the tofu liquid waste by cow rumen as inoculum. The installation of gas-flowed pipes was conducted by using paralon pipes with size ½ dan ¾ inch with the total lenght 8,40 m. The incubation period of the primary substrates was 30 days where the biogas volume quantification was periodically performed in the day of 10, 20, and 30. The results showed that biogas was formed at the incubation day of 10 which hence increase up to the day of 30. The observed gas volume was 223,568 cm3, 368,950 cm3 dan 458,302 cm3 respectively. The results of flame test representing blue flame indicated that the formed biogas contained the content of methane which higher than 70%. This hence revealed that the installation of biogas reactor with the type of “fixed domed plant” equipped by “watertrap” was able to produce a good quality biogas from the primary substrates were cow dung, chicken manure and the tofu liquid waste by cow rumen as inoculum for the application in the household scale.

PENGARUH KOMPOSISI SUBSTRAT CAMPURAN KOTORAN SAPI DAN JERAMI PADI TERHADAP PRODUKTIVITAS BIOGAS PADA DIGESTER SEMI KONTINYU

This study aims to determine the effect of substrate composition on biogas productivity from a mixture of cow dung and rice straw on semi-continuous digester. Rice straw used taken from Way Galih Village, South Lampung, and fresh cow dung was obtained from Laboratory in Department of Animal Husbandry, Faculty of Agriculture, University of Lampung. Biogas starter is filled with 26 liters of cow dung and water in 1: 1 ratio comparison based on weight. Then its being left for 4 day for stabilization. If the biogas production is stable, then substrate will be added with loading rate 0.5 liters / day, with 6 compositions of different cow dung and rice straw from the ratio of cow dung and elephant grass based on the following TS: P1 (75% : 25%), P2 (70% : 30%), P3 (65% : 35%), P4 (60% : 40%), P5 (55% :45%) dan P6 (50% : 50%). Parameters which observed in this study include daily temperature, pH, TS and VS substain, daily biogas volume, biogas productivity, and biogas quality. The results showed that in 6 treatments had the same average pH of 6,8. The average temperatures on the morning were 26,37 °C, 26,29 °C, 26,24 °C, 26,22 °C, 26,28°C, and 26,26 oC while in the afternoon respectively 29,58 °C, 29,47 °C, 29,48 °C, 29,49 °C,2 9,57 °C, and 29,61 oC. The total biogas production is 185,5 liter, 284,25 liter, 186,85 liter, 448,15 liter, and 108,55 liter, respectively for P1, P2, P3, P4, P5 and P6 with biogas productivity sequentially is 378,66 l/kg VSr, 684,87 l/kg VSr, 378,76 l/kg VSr, 1498,02 l/kg VSr, 587,21 l/kg VSr and 395,95 l/kg VSr. The quality of biogas through the flame test produces a bright blue flame color.

Flow and Temperature Characteristics of a 15° Backward-Inclined Jet Flame in Crossflow

The flow and flame characteristics of a 15° backward-inclined jet flame in crossflow were investigated in a wind tunnel. The flow structures, flame behaviors, and temperature fields were measured. The jet-to-crossflow momentum flux ratio was less than 7.0. The flow patterns were investigated using photography and Mie-scattering techniques. Meanwhile, the velocity fields were observed using particle image velocimetry techniques, whereas the flame behaviors were studied using photographic techniques. The flame temperatures were probed using a fine-wire R-type thermocouple. Three flame modes were identified: crossflow dominated flames, which were characterized by a blue flame connected to a down-washed yellow recirculation flame; transitional flames identified by a yellow recirculation flame and an elongated yellow tail flame; and detached jet dominated flames denoted by a blue flame base connected to a yellow tail flame. The effect of the flow characteristics on the combustion performance in different flame regimes is presented and discussed. The upwind shear layer of the bent jet exhibited different coherent structures as the jet-to-crossflow momentum flux ratio increased. The transitional flames and detached jet dominated flames presented a double peak temperature distribution in the symmetry plane at x/d = 60. The time-averaged velocity field of the crossflow dominated flames displayed a standing vortex in the wake region, whereas that of the detached jet dominated flames displayed a jet-wake vortex and a wake region source point.