PEMBUATAN RANGKA MESIN PENGADUK DIGESTER BIOGAS

Tujuan penyusunan proyek akhir yang berjudul proses pembuatan rangka mesin pengaduk digester biogas ini adalah mengidentifikasi bahan yang dibutuhkan, peralatan yang digunakan, proses yang dilakukan, serta uji kinerja dari rangka tersebut. Semua langkah ini dilakukan untuk memperoleh hasil produk sesuai dengan yang diinginkan dalam waktu yang efisien. Metode yang digunakan dalam pembuatan rangka mesin pengaduk digester biogas meliputi: (1). Menentukan bahan yang akan digunakan. (2). Memilih peralatan yang akan digunakan. (3). Langkah–langkah proses pembuatan rangka. (4). Melakukan uji rangka mesin pengaduk digester biogas. Bahan yang dibutuhkan untuk membuat rangka mesin pengaduk digester biogas adalah plat siku ukuran 40 x 40 x 4 mm. Bahan ini dipilih karena memiliki spesifikasi yang cukup kuat untuk rangka mesin. Alat dan mesin yang digunakan adalah alat lukis, mistar baja, mistar gulung, penitik, penggores, palu, gerinda potong, gergaji, gerinda tangan, kikir, amplas, ragum, sikat baja, mesin las listrik, mesin bor, dan kuas. Proses pembuatan rangka mesin pengaduk digester biogas di mulai dengan proses membuat rencana pemotongan (cutting plan) pada bahan. Pemotongan bahan menggunakan gerinda potong dan gergaji tangan. Selanjutnya dilakukan proses perakitan rangka dimulai dari pembuatan rangka bagian atas dan bagian bawah. Proses penyambungan dilakukan dengan mengelas. Pengelasan dilakukan menggunakan las SMAW (shielded metal arc welding) menggunakan elekroda AWS E 6013 Ø 3,2 mm. Proses finishing dengan proses pengamplasan dan pengecatan. Uji kinerja dilakukan untuk mengetahui kinerja dari rangka mesin pengaduk digester biogas yang dihasilkan. Dari hasil uji kinerja yang dilakukan, rangka yang dihasilkan mampu menopang komponen lain dari mesin serta mampu menahan getaran yang dihasilkan oleh putaran motor ketika beroperasi yang menggerakkan poros utama pada putaran 20 rpm

Cordova Psychrophiles Bio-Digester Benefit-Cost and Sensitivity Analysis

Cordova is located in southcentral part of Alaska, 150 miles southeast of Anchorage, and can be accessed only by boat or plane. The average winter temperature1 varies from 17⁰ F to 28⁰ F (-8⁰ C to -2⁰ C) and the average summer temperature varies from 49⁰ F to 63⁰ F (9⁰ C to 17⁰ C).2 To support Cordova’s ongoing energy independence efforts , the Denali Commission approved a science project for the Science Club students at Cordova High School using Emerging Energy Technology Funds to develop a bio-digester that uses psychrophiles, a cold climate bacteria, that can reproduce in very cold temperatures, as low as 19⁰ F (-7.5⁰ C).3 Use of psychrophiles in a bio-digester in Cordova is a new technology that aims to produce low cost biogas for Alaskans who live in extreme cold temperatures. The production of biogas varies significantly depending on ambient temperatures. The cold climate application of this technology is in its research and development (R&D) phase, which makes in-depth economic analysis challenging as there is little cost information and many parts for the application of the technology have to be custom build. This paper describes a preliminary economic analysis of the Cordova project. In order to provide a study at this early stage in technology development, the analysis was prepared using a combined benefit-cost and sensitivity analysis to show the impacts of variations in methane output, and diesel fuel and propane prices. For this preliminary analysis we compared the bio-digester technology against diesel and propane fuel alternatives.The Denali Commission. Alaska Center for Energy and Power.Table of Contents / List of Tables / Suggested Citation / Introduction / Economic Assumptions / Benefit-Cost Analysis and Sensitivity Analysis / Factors Driving the Benefit Cost Ratio / Conclusion / References / Appendix a. Estimated Present Values for the Psychrophiles Bio-digester / Appendix B. Fuel Price Projection / Appendix C. Anchorage CPI / Appendix D. Conversion Factors / Appendix E. Goal Seek for B-C ratio of 1 with Different Capital Costs / Appendix F. Goal Seek for B-C ratio of 1 with Different Labor and O&M Costs / Appendix G. Seek for B-C ratio of 1 with Different Total Cost

A New Experimental Pulp Digester Installation with Separate Steam Supply

Part I Literature Survey Up to now, few articles have been written on the subject of Experimental Pulp Digester Installations. In our searches we have been able to find information concerning only The Pulp and Paper Research Institute of Canada in Montreal, P.Q., Canada, The Chemical Pulp Experimental Department of the Central Laboratory in Finland, and a sulfite digester for research and instruction at the University of Washington at Seattle, Washington, U.S.A

Method for producing oxygen from lunar materials

This invention is related to producing oxygen from lunar or Martian materials, particularly from lunar ilmenite in situ. The process includes producing a slurry of the minerals and hot sulfuric acid, the acid and minerals reacting to form sulfates of the metal. Water is added to the slurry to dissolve the minerals into an aqueous solution, the first aqueous solution is separated from unreacted minerals from the slurry, and the aqueous solution is electrolyzed to produce the metal and oxygen

Assessment of Biofertilizer Quality and Health Implications of Anaerobic Digestion Effluent of Cow Dung and Chicken Droppings

Anaerobic digestate have been identified as a rich source of essential plant nutrients. Nevertheless, its safety measured by the concentration of pathogen present is of great concern to end users. This research explored the efficiency of the mesophilic biodigestion process in the stabilization and sanitization of cow dung and chicken droppings. Six (6) kg each of cow dung and chicken droppings were collected fresh and free from impurities, pre-fermented, mixed with water in the ratio 1:1 w/v to form slurry, fed into the respective reactors and digested for 30 days at an average ambient temperature of 30 � 2 �C. The pH of the medium fluctuated between 6.5 and 8.0. The analysis of the feedstock and effluent of the digesters showed that a total solids reduction of 75.3% and 60.1% were recorded for cow dung and chicken droppings while the reduction in total coliforms was 95% and 70% respectively for the dung and droppings. Microbial analysis of the biofertilizer produced reveals both aerobic and anaerobic organisms which include species of Pseudomonas, Klebsiella, Clostridium, Bacillus, Bacteroides, Salmonella, Penicillum and Aspergillus. Escherichia coli and Shigella spp. were removed while species of Salmonella and Klebsiella were still present in the digestate. Notwithstanding these results, the digestate still requires further treatment for it to be suitable for application on unrestricted crops either as fertilizer; otherwise a health problem would be created as attempt is made to improve soil fertilit

Effect of false flax oilcake in thermophilic biogas production

False flax oilcake has been found to be suitable for anaerobic fermentation in mixtures with cattle slurry and straw. In organic farms, digestion of cattle dung and wheat straw with 8 % dry matter content mixed with 5 % of total material weight false flax oilcake is a feasible option for utilizing false flax oilcake to produce farm-own renewable energy and offering farm-own high nitrogen (ammonia) content fertilizer (2.48 g kg-1 wet wt). In field digesters, the biogas yield of 8 % dry matter pure material under thermophilic condition was 0.24 l g-1 VS fed. The biogas yield could be increased by mixing 5 % false flax oilcake to get 0.37 l g-1 VS fed and a VS conversion efficiency with 0.83 l g-1 VS destroyed. Under laboratory controlled conditions, the biogas yield of slurry with 0.5 % oilcake was a little higher than biogas yield of the digestion of pure material, which was 0.26 and 0.24 l g-1 VS fed, respectively. Compared with the field experiment, only small amounts of biogas were produced in the lab-scale when 5 % oilcake was mixed in. The mixing can improve the biogas yield and substrate reduction in the digesters which have sufficient material. Further research is needed to find out the best controlled conditions (high-efficient bacteria, mixing frequency and time) and best equipment (for example: two phases digesters)

Co-digestion of the mechanically recovered organic fraction of municipal solid waste with slaughterhouse wastes

The current work aimed to resolve some long-standing questions about the potential benefits and limitations of co-digestion of slaughterhouse wastes. To achieve this, a laboratory-scale trial was carried out using the mechanically recovered organic fraction of municipal solid waste mixed with either sheep blood or a mixture of pig intestines with flotation fat. Both of these co-substrates are difficult to digest in isolation because of their high nitrogen and lipid concentrations, and are regulated as Category 3 materials under the Animal By-Products Regulations (EC 1069/2009). The results showed that at an organic loading rate of 2 kg VS m?3 day?1 with the slaughterhouse material making up 20% of the load on a volatile solids basis the process could operate successfully. As the loading was increased to 4 kg VS m?3 day?1 signs of inhibition appeared with both co-substrates, however, and volumetric methane production was reduced to a point where co-digestion gave no process advantage. The main operational problem encountered was an increase in the concentration of volatile fatty acids in the digestate, particularly propionic acid: this was thought to be a result of ammonia toxicity. The concentration of potentially toxic elements in the digestate made it unsuitable for agricultural application for food production, although the increased nitrogen content made it more valuable as a fertiliser for non-food crop use

Integration of on-farm biodiesel production with anaerobic digestion to maximise energy yield and greenhouse gas savings from process and farm residues

Anaerobic co-digestion of residues from the cold pressing and trans-esterification of oilseed rape (OSR) with other farm wastes was considered as a means of enhancing the sustainability of on-farm biodiesel production. The study verified the process energy yields using biochemical methane potential (BMP) tests and semi-continuous digestion trials. The results indicated that high proportions of OSR cake in the feedstock led to a decrease in volatile solids destruction and instability of the digestion process. Co-digestion with cattle slurry or with vegetable waste led to acceptable specific and volumetric methane productions, and a digestate low in potentially toxic elements (PTE). The results were used to evaluate energy balances and greenhouse gas emissions of the integrated process compared with biodiesel production alone. Co-digestion was shown to provide energy self-sufficiency and security of supply to farms, with sufficient surplus for export as fuel and electricit

Relating Anaerobic Digestion Microbial Community and Process Function

Anaerobic digestion (AD) involves a consortium of microorganisms that convert substrates into biogas containing methane for renewable energy. The technology has suffered from the perception of being periodically unstable due to limited understanding of the relationship between microbial community structure and function. The emphasis of this review is to describe microbial communities in digesters and quantitative and qualitative relationships between community structure and digester function. Progress has been made in the past few decades to identify key microorganisms influencing AD. Yet, more work is required to realize robust, quantitative relationships between microbial community structure and functions such as methane production rate and resilience after perturbations. Other promising areas of research for improved AD may include methods to increase/control (1) hydrolysis rate, (2) direct interspecies electron transfer to methanogens, (3) community structure–function relationships of methanogens, (4) methanogenesis via acetate oxidation, and (5) bioaugmentation to study community–activity relationships or improve engineered bioprocesses