Methane Gas Concentration Research Articles

Methane detection to 1 ppm using machine learning analysis of atmospheric pressure plasma optical emission spectra

Optical emission spectroscopy from a small-volume, 5 μl, atmospheric pressure RF-driven helium plasma was used in conjunction with partial least squares-discriminant analysis for the detection of trace concentrations of methane gas. A limit of detection of 1 ppm was obtained and sample concentrations up to 100 ppm CH4 were classified using a nine-category model. A range of algorithm enhancements were investigated including regularization, simple data segmentation and subset selection, feature selection via Variable Importance in Projection and wavelength variable compression in order to address the high dimensionality and collinearity of spectral emission data. These approaches showed the potential for significant reduction in the number of wavelength variables and the spectral resolution/bandwidth. Wavelength variable compression exhibited reliable predictive performance, with accuracy values >97%, under more challenging multi-session train—test scenarios. Simple modelling of plasma electron energy distribution functions highlights the complex cross-sensitivities between the target methane, its dissociation products and atmospheric impurities and their impact on excitation and emission.

Low-Cost Sensors Provide Insight into Temporal Variation in Fugitive Methane Gas Concentrations Around an Energy Well

Summary Effective measurement of the presence and rate of methane gas migration (GM) outside the casing of energy wells is important for managing social and environmental impacts and financial liabilities in the upstream petroleum industry. Practitioners typically assess GM by above-background methane gas concentrations in-soil or at-grade; however, factors influencing the potential variation in these measurements are not well represented in industry-recommended best practices. Inexpensive chemoresistive sensors were used to record a 1-minute frequency methane gas concentration time series over 19 days. Time series were recorded at three soil depths (0, 5, and 30 cm) at two locations <30 mcm radially from a petroleum well with known GM, in addition to two “control” locations. Observed concentration variations ranged over several orders of magnitude at all depths, with generally lower concentrations and more variation observed at shallower depths. Varying concentrations were correlated to meteorological factors, primarily including wind speed and shallow groundwater table elevation. The gas concentration patterns were affected by a 3.5-mm rainfall event, suggesting soil moisture changes affected preferential GM pathways. Results indicate potential variability in repeated snapshot GM test results. Although, currently recommended GM detection methods would have effectively identified the presence/absence of GM, they would not have quantified the order of magnitude changes in concentration. GM detection success at this site was increased with measurement at more than one location spatially within 30 cm of the well casing, lower concentration detection limits, and greater measurement depth. These findings indicate that meteorological factors should be considered when conducting GM surveys (particularly for improving at-grade test reliability). The low-cost approach for long-term concentration measurement facilitates insight into variable gas concentrations and may be advantageous in comparison to snapshot measurements in some circumstances.

Degasification of methane for high methane-emitted coal seam at Mao Khe coal mine - Vinacomin by drilling long borehole

This paper presents a technical solution for reducing methane gas concentration (degasification) caused by a high methane-emitted coal seam at Mao Khe coal mine - Vinacomin. The technique is implemented by drilling a long borehole from the footwall of the roadway into the coal seam and punching small holes along the borehole for gas release. A field study at the longwall level -150/-80 m at Seam 9 of Mao Khe coal mine shows that after the degasification, the gas concentration here is lowered to safety standards. The technique can be used for all coal seams ranked as Class II, Class III, and super-class regarding methane gas, minimizing the risk of methane combustion and explosion.

Development and Application of Methane Leakage Monitoring System for Gas Transmission Pipeline

Oil and gas pipeline transportation, as a relatively safe way of oil and gas transportation, undertakes most of the transportation tasks of crude oil and natural gas. Oil and gas pipeline accidents affect a wide range of consequences. Therefore, the oil and gas pipeline leakage detection is paid more and more attention. In this paper, ultra-low power methane gas sensor is selected to collect methane gas concentration in the air, and wireless network technology is used to build a wireless network sensor system with 4G function. Through the sensor distribution along the pipeline, it can intuitively and accurately judge whether there is a micro-leakage in the pipeline, and understand the diffusion situation after the leakage. The sensor system has high reliability and stability, and has high value of popularization and application.

The Effect of Supplementation of Cassava Leaves, Palm Oil Sludge and Yeast in Kumpai Grass-Based Rations on Ruminal Fermentation and Gas Methane Concentration In-Vitro

Swamp forage (kumpai grass), waste products from plantations, and agricultural industries are alternative feed for ruminants. To increase the value of its availability, yeast supplementation is needed. This study aimed to determine the effect of kumpai grass-based ration supplemented with cassava leaves, palm oil sludge, yeast on digestibility, rumen fermentation characteristics, and methane gas production. This study was determined using a Completely Randomized Design consisting of four treatments. The treatment is described as follows 70% grass + 30% Concentrate (P0, Con), 55% grass + 30% cassava leaves + 15% Concentrate + 0.05% yeast (P1), 55% grass + 30% palm oil sludge + 15% concentrate + 0.05% yeast (P2), and 55% kumpai grass + 15% cassava leaves + 15% palm oil sludge + 15% concentrate + 0.05% yeast (P3). Each treatment was incubated In-Vitro with a buffer solution (pH 6.9) and rumen of four replications (each repetition represented by three incubation bottles) for 48 hours at 39 ºC. The data obtained were analyzed for variance; if there were a treatment effect, the Duncan test can be further tested. The results showed that supplementation affected the increase (P <0.05) of dry matter digestibility, organic matter, crude protein, neutral detergent fiber, acid detergent fiber, total volatile fatty acids (total VFA), partial VFA, and total bacteria. Whereas, N-ammonia (N-NH3), the ratio of acetate-propionate and methane gas has decreased. It was concluded that supplementation of 15% cassava leaves, 15 % palm oil sludge, and 0.05% yeast in kumpai grass-based rations gave the best increase in the ration digestibility, total rumen bacterial count, rumen fermentation characteristics, and reduced methane concentration.

A Late-Model Optical Biochemical Sensor Based on OTS for Methane Gas and Glucose Solution Concentration Detection

The traditional sensor structures are usually designed for single-function detection, but a dual-function optical biochemical sensor that can simultaneously detect methane (CH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> ) gas and glucose solution concentrationvia the change of refractive index (RI) is proposedin this paper,which is suitable for multiple application scenarios. Two kinds of cavities with different thicknesses are developed for gas and liquid measurement respectively. The sensitive and narrow absorption peak benefits from the optical Tamm state (OTS) based on the metal properties, which provides the basis for high-precision detection. By coating the CH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> -sensitive membrane, the qualitativea nd quantitative analysis of CH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> concentration <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$C_{CH4}$ </tex-math></inline-formula> of 0–3% (RI of 1.4364–1.4478) can be accurately realized. The sensitivity (S) is 7.89 THz/RIU, the figure of merit (FOM) is up to 1315, the quality (Q) value is 88832, and the lower detection limit (DL) is about 3.8 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times$ </tex-math></inline-formula> <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10^{-5}$ </tex-math></inline-formula> . If such a sensor is used to detect the concentration of glucose aqueous solution ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$C_{G}$ </tex-math></inline-formula> ) of 140–330 g/L (RI of 1.3489–1.3715), the corresponding values are 2.55 THz/RIU, 319, 66601, and 1.5 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times$ </tex-math></inline-formula> <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10^{-4}$ </tex-math></inline-formula> , which can provide the possibility for the biomedicine blood glucose detection. In addition, the effects of different metal layer thicknesses on sensor performance are discussed briefly.

Correlation between adsorbed methane concentration and pore structure of organic-rich black shale from the Liard Basin, Canada

Evaluating the adsorbed gas content in shale gas reservoirs is crucial for calculating total gas production potential of the reservoir. In this study, we analyzed the chemical composition and total organic carbon content of the black shale samples collected from different depths in the Liard Basin, Canada. The samples were identified as siliceous-rich shale samples; specifically, organic-rich black shale with a total organic carbon content of more than approximately 3%. We also analyzed the adsorbed methane gas content and the pore structure of the shale samples. We conducted a mechanistic study to identify the important factors affecting the amount of adsorbed CH4 gas in the shale by evaluating the correlation between the adsorbed CH4 gas content and quantitative pore structure results (i.e., specific surface area and micropore, mesopore, and macropore volume). The results indicate that the micropore volume can be effectively used to predict the content of adsorbed CH4 gas in organic-rich black shale samples from the Liard Basin.

Methane Emission Estimation and Dispersion Modeling for a Landfill in West Java, Indonesia

Methane gas (CH4) is a greenhouse gas that can potentially induce global warming and it is known as surface ozone precursor. CH4 is generally produced from biological process occurred at the landfill which is not equipped with CH4 recovery and treatment system. Note that, very few of landfills in Indonesia have been operated as sanitary landfill but rather most of them act as dumping site. One landfill in West Java Province is Sarimukti Landfill which receives nearly 604,674 ton of solid waste annually. Existing studies have been using the first tier of the Intergovernmental Panel on Climate Change (IPCC) guideline for the emission estimation which provides high uncertainty due to the international default data. In addition, there are uncertainties for the multi years estimation because the kinetic rate of biological processes was not involved in the calculation. To fill in this gap, this research was conducted to use an alternative of methodology for estimating CH4 from landfill using a well known software of the Landfill Gas Emissions Model (LandGEM) which facilitates biological reaction in the calculation. We will also perform calculations using the traditional IPCC method for the Sarimukti landfill as a case study. To quantify the impact of CH4 emission, its dispersion was calculated using the AMS/EPA Regulatory Model (AERMOD). Potential impact on surface ozone formation was assessed using ozone formation potential (OFP) metric. The results of this study indicate that methane gas emissions have increased every year, where the highest emissions occurred in 2025 of 14,810.41 Mg/year (LandGEM) and 11,462.66 Mg/year (IPCC). Likewise, the potential for OFP from methane gas concentrations has increased every year where the highest concentration of surface ozone formation is in 2025 of 183,40 Mg/year. Meanwhile, the methane emission (CH4) has a dispersion pattern which is influenced by meteorological factors around the Sarimukti landfill.

Study of Spatial Distribution of Greenhouse gases (methane gas) Over Iraq using Geostatistical Analysis

Wetlands are one of the most important natural resources on Earth. Marshes are important wintering and resting area for migratory water birds and other migratory birds. Historical data on bird migration in the Marshes suggest that they were one of the largest wintering areas for migratory water birds in the Middle East. The Iraqi marshlands lies in the floodplain which is created by the Tigris-Euphrates river system in the lower part Mesopotamia basin. The existence of water vapor, carbon dioxide, methane and ozone in the troposphere makes surface of our planet habitable. The greenhouse gases absorb thermal radiation and also emit these wavelengths, making the mean surface temperature of the earth higher, and contribute to global warming. Human activities produce large amounts of greenhouse gases, like carbon dioxide, methane, ozone and others. Methane is produced by the decomposition of plants in wetlands. Geostatistical interpolation methods are adopted in this paper. We use the analyst in ArcGIS to apply cross-validation. The cross-validation calculate some criteria to insure the accuracy of predictions made using the ordinary kriging method. Maps were created for methane over Iraq. Cross validation errors were calculated using ArcGIS. The produced maps assure that lower Mesopotamian basin have high concentration of Methane gas which make it as a wintering and resting area for migratory water birds.

Simple preparation of Ni/CuO nanocomposites with superior sensing activity toward the detection of methane gas

Composite nanostructures composed of transition metal oxides are promising materials in catalyst, supercapacitor, and gas sensors. Here we have used Ni for the enhancement of the CuO gas sensor toward methane gas. High-quality Nix/CuO nanocomposites (where x = 0.0 to 10%) have been synthesized by the simple method of solid–solid reaction. A nanoparticle structure was obtained. The size of the nanoparticle can be controlled easily by adjusting the relative Ni concentration in Ni/CuO nanoparticles. The relative diffusion amount of Ni to CuO was proved to be the key factor to influence the sensing sample properties. XRD patterns and HRTEM image confirmed the preparation of Nix/CuO phase, which showed a decline in crystallite size from ~ 17.8 to 14.6 nm (XRD). FESEM and TEM images also exhibited the effect of Ni content on the particle size of CuO. EDX mapping confirmed that the NiO fine particles were distributed semi-uniform at low Ni concentration; however, they aggregated at high Ni concentration. The sensing properties were done at different temperatures and various concentrations of methane gas. It was illustrated that the increase of Ni up to 5% showed an improvement in the sensor response of CuO toward methane compared to the pure phase of CuO and NiO, as well. The maximum-response temperature was 250 °C at which the sensor response is ~ 4.9 (390%), which is four times higher than the CuO and NiO pure phases. The present nanocomposites could detect CH4 at lower levels of explosive level (5%). The mechanism of gas sensing is explained depending on the electronic structure changes.

Developing low-cost methane gas concentration measuring device

In every aspect of Engineering more advanced, efficient and progressive solutions are required. The modern age of science requires innovative minds. The field of environmental engineering is also advancing with modern science and technology innovations. Measuring of methane concentration and flow rate is nothing new, yet a complicated process. The need for more accurate measurement is a necessity in proper operation of bio digesters for methane generation. The traditional process of the measuring methane content in biogas is time consuming yet complicated. The need for development and application of methane measurement techniques is not only limited to biogas but has other monitoring value as well in other health and safety applications in built environments. Winsen Electronics and Hanwei Electronics are two of the leading sensor-manufactures of China who are providing a wide range of gas detecting sensors that are locally available in Bangladesh and yet has not been applied to methane content measurement in biogas operations. In This paper we are reporting on the application of a purpose-built propane, butane detector for methane gas detection within the range of accuracy for it to be applied in methane detection in a biogas stream. This paper, reports on application and calibration of the methane detecting sensor MQ-4 with promising result. Based on the study we postulate that the sensor can be used to detect methane for an on-line monitoring of many environmental, industrial purposes such as bio digesters, integrated waste management facility. The cost of fabrication of the sensor system is only $18 making it a viable sensor with respect to cost for application in Bangladesh.

Penggunaan Aplikasi Blynk untuk Sistem Monitoring dan Kontrol Jarak Jauh pada Sistem Kompos Pintar berbasis IoT

In the composting process, there are several aspects that need to be considered, namely temperature, humidity, pH content, and methane gas content in the compost. So that users can still monitor the condition of the compost during the composting process even though it is far from the compost location, this research provides an alternative solution to overcome this problem. The tool made in this study combines the capabilities of the Wemos D1 R1 as a data acquisition system equipped with a wifi module for sending data via the internet network, dht 22 sensor, pH sensor, and mq 4 sensor to determine the methane gas content in compost, and a special Android application blynk. as a monitoring aid. Wemos D1 R1 is also connected to a relay to regulate the ignition of a water pump or EM4 solution and two ac motors. Based on the tests conducted, it was found that each module can work properly according to its function and the results displayed in the Blynk application with the serial monitor are not much different and also at a distance of 25 m the device can still be controlled using the Blynk application even though there is a delay.

Concentration of Partial VFA and Methane Production of Beef Cattle Rument Fluid which Red Dragon Fruit Skin (Hylocereus costaricensis) and Guava Leaf (Psidium guajava L.) in Ammoniated Rice Straw Based Ration

The research aimed to examine the effect of red dragon fruit skin and guava leaves supplemented into beef cattle feed on the concentration of partial VFA and methane gas production. The in vitro study was conducted in a completely randomized design (CRD) with 3 treatments, namely P0: 50 % concentrate + 50 % ammoniated straw (Control), P1: 50 % concentrate + 50 % ammoniated straw + 5 % red dragon fruit skin flour, and P2: 50 % concentrate + 50 % ammonia straw + 5 % red dragon fruit skin flour + 2.5 % guava leaf flour. The concentrate consisted of 2 parts of rice bran and 1 part of coconut meal. The ratio of concentrat and ammoniated rice straw was 50:50. Each treatment was repeated 6 times. The results showed that the concentration of acetic acid, butyrate and methane gas decreased while the concentration of propionate increased with the addition of red dragon fruit and guava leaves. The research concluded that the addition of 5 % red dragon fruit skin flour combined with 2.5 % guava leaves flour in beef cattle feed could further reduce the concentration of acetic acid, butyric acid and the production of methane gas, but increase the concentration of propionic acid. It is suggested that defaunated agents of red dragon fruit skin and guava leaves could reduce the production of methane gas in the rumen of beef cattle.

Design of ECU (Electronic Control Unit) as Biogas Pressure Control to Micro Genset

Biogas fueled generator has a unique character because the converter kit on the generator has the characteristic of absorbing the biogas supply. Therefore, in this study, biogas is accommodated in a plastic container equipped with a valve that can adjust the amount of biogas supply pressure. Combustion in the Genset combustion chamber will occur if the ratio of air supply and supply of biogas (AFR = Air to Fuel Ratio) meets the stoichiometric number. So a ratio control is needed on air supply and biogas supply, which can follow changes in biogas conditions in plastic bags and generator loads. For this reason, this paper presents an ECU (Electronic Control Unit) that can regulate the ratio of air supply to biogas supply by using a servo motor valve, which is commanded by a control signal from the ECU. The resulting ECU prototype is equipped with a multi-input connector (to receive the signal output of CH 4 methane gas sensor and the biogas supply pressure sensor), multi-output (control signal to the servo motor valve), and multi regulators to adjust the Set Point value for the methane gas content CH4, the value of the set point of the biogas supply pressure and to tune the value of the proportional gain control (KP). The results of the ECU performance test by trial and error by giving a dummy input signal (analogy to the signal output of methane gas sensor and the analog of the pressure sensor output signal in the form of an electric voltage generated from the signal generator) can drive the servo motor, valve air supply, and servo motor, valve supply biogas. Accordance with the gain control input from the regulator.

Micropore Characteristics and Gas-Bearing Characteristics of Marine-Continental Transitional Shale Reservoirs in the East Margin of Ordos Basin

In order to deeply study the exploration potential of Carboniferous-Permian marine-continental transitional shale reservoirs in the Ordos Basin, the shale samples from well Y1 in the central-southern part of the Hedong Coalfield were used as the research object. The organic geochemical test, scanning electron microscope, X-ray diffraction, and high pressure mercury injection and low-temperature nitrogen adsorption experiments have studied the microscopic characteristics and gas content characteristics of shale reservoirs. The results show that the organic matter type of the sample is type III; the TOC content ranges from 0.28% to 16.87%, with an average of 2.15%; [Formula: see text] is from 2.45% to 3.36%, with an average value of 2.86%; the shale pores in the study area are well developed, containing more organic pores and intergranular pores of clay minerals. Based on the two-dimensional SEM image fractal theory to study different types of pores, the fractal dimension of shale pore fracture morphology is between 2.34 and 2.50, and the heterogeneity is moderate. The high-pressure mercury intrusion experiment characterizes the pore size distribution of shale macropores and transition pores. The pore diameters are mostly nm-scale. Transition pores are the main pores of the shale in the study area. Based on the characteristics of the pore structure, the adsorption capacity and gas content of CH4 in shale reservoir were analyzed by methane isothermal adsorption and gas content experiments. The results showed that the pore volume and specific surface area were positively correlated with clay mineral content, TOC, and RO, but negatively correlated with the quartz content. In clay minerals and brittle minerals, pore volume and specific surface area are positively correlated with illite content and negatively correlated with the quartz and kaolinite content. The measured total gas content and desorbed gas content are significantly positively correlated with TOC, but are weakly positively correlated with the quartz and illite content. This study finely characterizes the physical properties, micropore characteristics, gas-bearing characteristics, and influencing factors of shale reservoirs, which has certain theoretical guiding significance for the research and development of coal-measure shale in the Ordos Basin.

Potential and characterization biogas from tofu liquid waste with addition cow dung and effective microorganisms 4 as biocatalyst

Energy is a source that needed by human life and cannot be separated. Fossil fuel has historically been the world’s most used energy source. However, the source of energy from fossil fuels has decreased, so it necessary to develop alternative energy sources. One of the energy sources that can be used is biogas. Organic wastes such as tofu liquid waste (TLW) and cow dung can be used as a source of biogas energy, because these organic wastes are known to have high methane gas content. The purpose of this research is to determine the optimum temperature and pH during the process fermentation of biogas, the content of biogas compounds analyse, the theoretical calorific value of biogas, as well as the BOD, COD, and TSS content of organic waste before and after fermentation process. The biogas production takes place through anaerobic digestion for about 35 days. From the results of this study, the highest CH4 gas content was 90.351%. The result of theoretical biogas calorific value was 50148.932 kJ/kg for HHV and 46908.932 kJ/kg for LHV, temperature conditions in range of 25–30 °C and a pH value in the range of 7.0 to 8.0. Besides producing energy, the organic waste fermentation process can also reduce levels of organic pollutants BOD, COD, and TSS in the liquid waste used. The highest decrease in BOD, COD, and TSS levels were 97.52%; 91.12%; and 91.22%.

Geological methane emissions and wildfire risk in the degraded permafrost area of the Xiao Xing\u2019an Mountains, China

With global warming, the carbon pool in the degradation zone of permafrost around the Arctic will gradually be disturbed and may enter the atmosphere in the form of released methane gas, becoming an important factor of environmental change in permafrost areas. We selected the northwestern section of the Xiao Xing'an Mountains in China as the study area, located in the degradation zone on the southern margin of the permafrost region in Eurasia, and set up multiple study monitoring areas equipped with methane concentration sensors, air temperature sensors, pore water pressure sensors and soil temperature sensors for long-term monitoring of data changes using the high-density electrical method, ground penetrating radar and on-site drilling to survey the distribution of frozen soil and geological conditions in the study area, combined with remote sensing images of Sentinel-2 L1C and unmanned aerial vehicle photographs and three-dimensional image reconstruction, analysis of fire activities and related geological environmental factors. The results show that since 2004, the permafrost thickness of the marsh wetland in the study area has gradually reduced and the degradation rate obviously accelerated; the organic matter and methane hydrate (metastable methane hydrate and stable methane hydrate) stored in the permafrost under the marsh wetland are gradually entering the atmosphere in the form of methane gas. Methane emissions show seasonal changes, and the annual methane emissions can be divided into three main stages, including a high-concentration short-term emission stage (March to May), a higher-concentration long-term stable emission stage (June to August) and a higher-concentration short-term emission stage (September to November); there is a certain correlation between the change in atmospheric methane concentration and the change in atmospheric pressure and pore water pressure. From March to May every year (high-concentration short-term emission stage), with snow melting, the air humidity reaches an annual low value, and the surface methane concentration reaches an annual high value. The high concentration of methane gas entering the surface in this stage is expected to increase the risk of wildfire in the permafrost degradation area in two ways (increasing the regional air temperature and self-combustion), which may be an important factor that leads to a seasonal wildfire frequency difference in the permafrost zone of Northeast China and Southeast Siberia, with the peak in spring and autumn and the monthly maximum in spring. The increase in the frequency of wildfires is projected to further generate positive feedback on climate change by affecting soil microorganisms and soil structure. Southeastern Siberia and northeastern China, which are on the southern boundary of the permafrost region of Eurasia, need to be targeted to establish fire warning and management mechanisms to effectively reduce the risk of wildfires.

Potensi Kandungan Gas Metana sebagai Sumber Energi Alternatif di TPA Kebon Kongok

Waste management in West Nusa Tenggara Provincial Government focuses on two main things, namely the reduction and handling and providing of TPA which is still operated with an open dumping system. Application of an open system in TPA will cause many problems, including air pollution by methane gas and the greenhouse effect. This study aims to determine the potential methane gas content of the Kebon Kongok landfill as an alternative energy source by modelling using LandGEM. The data in this study consisted of the year of the TPA operation plan and the annual data on the waste generation of TPA. The results showed that the potential content of methane gas was 12,999,633.62 m3/year, or equivalent to 14,520.88 MWh/year, in the form of gas as much as 9,966.38 Megagrams of LPG/ year. Therefore, the Kebon Kongok TPA has the potential to be used as a power plant fuelled by methane gas and facilitates electricity connections for the surrounding community because when compared to other existing renewable energy plants in the Lombok Electricity System, the capacity of 1.66 Megawatts was already equivalent to the power generation capacity which are already operating commercially.

Pembuatan Biogas dari Limbah Cair Tahu Menggunakan Bakteri Indigeneous

Air limbah tahu merupakan bahan pencemar apabila dibuang ke lingkungan perairan karena dapat menimbulkan bau busuk, penyakit dan menurunkan konsentrasi oksigen terlarut. Pada sisi lain, air limbah tahu dapat digunakan sebagai sumber energi alternatif yaitu biogas. Penelitian bertujuan untuk mengetahui pengaruh waktu fermentasi, volume substrat dan waktu pengadukan terhadap produksi biogas dan gas metana. Variabel yang digunakan dalam percobaan, antara lain: volume starter (10%, 20%, 30% dan 40% (v/v)); waktu pengadukan (1 hari, 7 hari, dan 14 hari), waktu fermentasi (5 hari, 10 hari, 15 hari, 20 hari, dan 25 hari). Penelitian dilakukan dengan menggunakan digester yang memiliki volume 50 liter yang diisi dengan starter berupa bakteri indigeneous dan limbah cair tahu pada persen volume tertentu. Selanjutnya digester dialiri gas N2 hingga digester berada pada kondisi anaerobik kemudian dilakukan pengadukan (1 hari, 7 hari, 14 hari) atau tanpa pengadukan. Pada setiap 5 hari hingga 25 hari dilakukan pengambilan sampel dan pengukuran volume biogas dan gas metana (CH4) yang dihasilkan menggunakan alat gas analyzer. Hasil percobaan menunjukkan bahwa volume biogas dan gas metana terbanyak dihasilkan pada waktu fermentasi 20 hari, dengan pengadukan 14 hari, dan volume starter 30% dapat menghasilkan biogas dan gas metana (CH4) masing – masing sebesar 5.000 ml dan 540 ml. Tofu wastewater is a pollutant when discharged into the aquatic environment because it can cause foul odors, diseases and reduce the concentration of dissolved oxygen. On the other hand, tofu wastewater can be used as an alternative energy source, namely biogas. The study aims to determine the effect of fermentation time, starter volume and stirring time on biogas and methane gas production. Variables used in the experiment included: volume of starter (10, 20, 30, and 40% (v/v)); stirring time (1, 7, and 14 days), fermentation time (5, 10, 15, 20, and 25 days). The research was conducted using a digester that has a volume of 50 liters filled with starter as much as 10, 20, 30 and 40% (v/v). Then the digester is flowed with N2 gas until the digester is in anaerobic condition then stirring (1, 7, and 14 days) or without stirring. Every 5 days to 25 days a sample is taken and the amount of biogas and methane gas (CH4) produced is measured directly using a gas analyzer. The experimental results show that the highest volume of biogas and methane gas produced during fermentation time of 20 days, with a stirring of 14 days, and a volume of starter of 30% which can produce biogas and methane gas (CH4) respectively of 5,000 ml and and 540 ml.

THE EFFECT OF HARMFUL AND FAVORABLE GAS AND CHEMICAL CONTENT EMITTED BY MUD VOLCANO TO ENVIRONMENT

The recent eruption of Kesongo mud volcano (MV) that occurred in 28August 2020 in Blora, Central Java was a common natural phenomenon.MV eruption occurred periodically depending on the recharge fluid systemthat interconnected to a geothermal system and hydrocarbon reservoir.During the eruption, methane and CO2 gas were emitted to theatmosphere together with rocks, muds and fluids flowing from the fractureand fault system of MV. The extruded materials could be harmful andbeneficial for the affected ecosystem. Aims: This study aimed to addressthe potential impact of the extruded mud volcano materials to theenvironment. Methodology and Results: An attempt was carried out byinvestigating gas and fluid content of every mud volcano morphology in theselected 11 areas of Kradenan, Central Java and Sidoarjo, East Java. The pristine fluids and gas of MV were sampled for chemical and toxiccompound observation. Gas composition and type was observed using gaschromatography. The result shows that methane gas content ranges from0.06 to 67.6 mol%., while the CO2 content ranges from 0.21 to 79.9 mol%.Methane gas exhibits thermogenic gas that associated with hydrocarbongeneration. Conclusion, significance and impact study: The chemicalcompound of fluids indicates high Boron (B) content above 0.5 ppm whichhas harmful effect for crops and human health, but some compounds ofCa, Na, K, Mg present as essential elements for soil nutrient. According tothe methane flux and chemical compound emitted by mud volcano, thisstudy contributes to a management practice to restore and conserve the global ecosystem.