Analysis and Comparison of Biochar From Pilot Scale Downdraft Gasifier

2015 ◽  
Author(s):  
Tejasvi Sharma ◽  
Yunye Shi ◽  
Guiyan Zang ◽  
Albert Ratner

Gasification is incomplete combustion of solid fuel that results in the production of vapor, often referred to as syngas or producer gas, char, and tar. When this process is applied to biomass, the resulting char, referred to as biochar, is produced and has been shown to enhance soil fertility and crop growth. As part of a broader effort, this work examines how the gasification process impacts the biochar generated through downdraft gasification. In contrast to previous publications, which only focused on the syngas compositions, this research paper expands the analysis to the composition of the biochar produced in the gasification systems. In a large-scale gasifier, corn grains at about a 15% moisture level are inserted into a pilot scale downdraft gasifier from the top. In this system, both air and fuel move in the same direction. The air entering the setup is controlled using a damper. Corn grains entering the gasifier pass through a drying zone where the moisture content in it is removed. The dry corn then passes through a combustion and pyrolysis zone, followed by a reduction zone. The high temperature present at the bottom in the reduction zone cracks any tar present in the syngas produced. This syngas exits from the bottom of the gasifier. The char produced has a residence time from half an hour to several hours. About 20% of the fuel that’s inserted in the gasifier is converted to biochar. An ultimate and proximate chemical composition analysis, BET porosity analysis, and an SEM image analysis were carried out on the biochar produced from this system. From the SEM analysis, a surface area of 2.38 m2/g was obtained. From the ultimate and proximate analysis, it was observed that the biochar had higher carbon content and a lack of volatile components compared to other reported biochars and levels similar to activated carbon. From the BET porosity analysis, both small scale and large-scale pores were observed but quantified comparison with other biochar is still on going. Porosity is known to be an important factor in biochar effectiveness as a soil amendment.

1973 ◽  
Vol 30 (12) ◽  
pp. 2172-2177
Author(s):  
P. C. George

Small-scale fisheries have traditionally been the backbone of the fishing industry all over the world. Although large-scale mechanized fishing has come into the limelight recently, even such countries as have developed substantial capability in this direction still have a large fleet of small boats in coastal areas. The landings of this sector of the industry are always substantial, and in many countries they still dominate the picture. In India, small-scale fisheries landed almost 1.15 million tons in 1971. This figure has been increasing as motor-powered small craft have increased in numbers, although 70% of marine fish is still caught from nonpowered boats. Measures taken to increase fishing capacity, landings, and net fishermen’s income over the past 10 years include various kinds of loans and subsidies for the purchase of boats, motors, and nets; assistance for the construction of ponds in inland areas; organization of cooperatives; training programs for fishermen and supporting personnel, especially motor repairmen (with the cooperation of Norway); and gear and vessel research including pilot-scale demonstrations with new types of vessels and equipment.


Author(s):  
Jukka Konttinen ◽  
Mikko Hupa ◽  
Sirpa Kallio ◽  
Franz Winter ◽  
Jessica Samuelsson

When a solid fuel, such as coal, biomass or a mixture of these fuels, enters a hot fluidized bed, the volatile carbon and nitrogen compounds are released, while some nitrogen and carbon remains in the solid char. Volatile nitrogen can form reactive species such as NH3, HCN and tar-nitrogen. These can react in the presence of oxygen to NO (and some N2O). Some part of volatile nitrogen is always reduced to N2. During combustion of the char residue, some part of the char-nitrogen forms NO (or N2O) and the rest is converted to N2. Usually the standard fuel analysis is not enough to allow for accurate NO emission predictions in large scale fluidized bed combustion. This paper presents NO formation tendency characterization results from novel laboratory measurements in a small-scale fluidised bed combustor. The laboratory results of this paper give a good insight into the distribution of fuel nitrogen between reactive and non-reactive (N2) volatile components and char-nitrogen. A NO formation tendency database is formed based on the results, including data on biomass-, waste-, peat- and coal-type fuels. The combustion test results show that the cumulative conversion of fuel nitrogen to NO under lean, non-staged fluidized bed combustion is 20–50% (850°C with O2 in excess). For biomass and peat, nearly all reactive nitrogen (forming NO) is released from the fuel during pyrolysis. NO formation during char combustion is significant with coal. With the help of the database, a reasonable estimate of the maximum non-staged NO emission in fluidized bed combustion can be obtained. Normally, air staging is utilized to reduce NO emissions. Effects of air-staging can be studied by means of modelling. In case of a BFBC boiler, the data can be used as input in the design or modelling of air staging for freeboard. For CFBC, the data can be used as input in the NO prediction where the once formed NO is further reduced by char carbon.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Agnieszka Dudkiewicz ◽  
William Hayes ◽  
Bukola Onarinde

PurposeThe purpose of this pilot-scale study was to compare the quality of traditionally manufactured butters from local, small British producers with the quality of butters that are produced industrially.Design/methodology/approachButter samples were obtained after supervised site inspections of three traditional-butter manufacturers and one large-scale butter producer. The samples were subject to initial microbiological, chemical and sensory testing, followed by a refrigerated shelf-life study over 24 weeks.FindingsTraditional butters matched or exceeded the sensory quality of industrial butters, but spoilage microorganisms tended to grow faster on traditional butters. This seemed to be related to poorer water droplet dispersion in the manufacture of some of the traditionally made butters. Visible mould appeared on two of the traditional butters after eight weeks, but this occurred well after the nominal “best before” date.Originality/valueProlonged lockdowns due to the current coronavirus disease (COVID-19) pandemic pose a threat to the food supply chain, and food produced by local manufacturers may become increasingly important. However, are foods produced by local small-scale manufacturers of a quality comparable to that produced using large-scale production facilities? To the best of the authors' knowledge, there is no comparative study of the quality and shelf-life of traditionally-produced and industrially-produced butters. The current work presents such a comparison together with an outline of how the process of traditional butter-making differs from commercial production in Britain.


2014 ◽  
Vol 931-932 ◽  
pp. 1033-1037
Author(s):  
Pongdee Chaijunda ◽  
Chaiyaput Kruehong ◽  
Mallika Thabuot ◽  
Chattichai Waisurasingha ◽  
Prinya Chindaprasirt

This research presents the effect of fuel type on temperature profile within the pyrolysis-, combustion-and reduction-zone of the pilot-scale downdraft gasifier, and the replacement potential of LPG with syngas for electricity production. The experimental results showed that gasification of different fuels have the distinctions of temperature level in each zone. More stable syngas production was obtained either from wood chips (WC) or plastic carrier bag (PCB). In contrast, gasification of aluminum coated plastic bag (ACPB) showed the unsatisfied syngas. From the operation with the dual mode of LPG and syngas for electric production, LPG consumption was reduced about 27.08%, 14.58% and 8.33% when PCB-, WC-and ACPB-syngas were used, respectively.


2000 ◽  
Vol 45 (4) ◽  
pp. 396-398
Author(s):  
Roger Smith
Keyword(s):  

2020 ◽  
Vol 1 (1) ◽  
pp. 1-10
Author(s):  
Evi Rahmawati ◽  
Irnin Agustina Dwi Astuti ◽  
N Nurhayati

IPA Integrated is a place for students to study themselves and the surrounding environment applied in daily life. Integrated IPA Learning provides a direct experience to students through the use and development of scientific skills and attitudes. The importance of integrated IPA requires to pack learning well, integrated IPA integration with the preparation of modules combined with learning strategy can maximize the learning process in school. In SMP 209 Jakarta, the value of the integrated IPA is obtained from 34 students there are 10 students completed and 24 students are not complete because they get the value below the KKM of 68. This research is a development study with the development model of ADDIE (Analysis, Design, Development, Implementation, and Evaluation). The use of KPS-based integrated IPA modules (Science Process sSkills) on the theme of rainbow phenomenon obtained by media expert validation results with an average score of 84.38%, average material expert 82.18%, average linguist 75.37%. So the average of all aspects obtained by 80.55% is worth using and tested to students. The results of the teacher response obtained 88.69% value with excellent criteria. Student responses on a small scale acquired an average score of 85.19% with highly agreed criteria and on the large-scale student response gained a yield of 86.44% with very agreed criteria. So the module can be concluded receiving a good response by the teacher and students.


2019 ◽  
Vol 61 (1) ◽  
pp. 5-13 ◽  
Author(s):  
Loretta Lees

Abstract Gentrification is no-longer, if it ever was, a small scale process of urban transformation. Gentrification globally is more often practised as large scale urban redevelopment. It is state-led or state-induced. The results are clear – the displacement and disenfranchisement of low income groups in favour of wealthier in-movers. So, why has gentrification come to dominate policy making worldwide and what can be done about it?


2020 ◽  
Vol 9 (2) ◽  
Author(s):  
Bùi Thị Bích Lan

In Vietnam, the construction of hydropower projects has contributed significantly in the cause of industrialization and modernization of the country. The place where hydropower projects are built is mostly inhabited by ethnic minorities - communities that rely primarily on land, a very important source of livelihood security. In the context of the lack of common productive land in resettlement areas, the orientation for agricultural production is to promote indigenous knowledge combined with increasing scientific and technical application; shifting from small-scale production practices to large-scale commodity production. However, the research results of this article show that many obstacles in the transition process are being posed such as limitations on natural resources, traditional production thinking or the suitability and effectiveness of scientific - technical application models. When agricultural production does not ensure food security, a number of implications for people’s lives are increasingly evident, such as poverty, preserving cultural identity, social relations and resource protection. Since then, it has set the role of the State in researching and building appropriate agricultural production models to exploit local strengths and ensure sustainability.


2018 ◽  
Vol 1 (3) ◽  
pp. 156-165 ◽  
Author(s):  
Nasirudeen Abdul Fatawu

Recent floods in Ghana are largely blamed on mining activities. Not only are lives lost through these floods, farms andproperties are destroyed as a result. Water resources are diverted, polluted and impounded upon by both large-scale minersand small-scale miners. Although these activities are largely blamed on behavioural attitudes that need to be changed, thereare legal dimensions that should be addressed as well. Coincidentally, a great proportion of the water resources of Ghana arewithin these mining areas thus the continual pollution of these surface water sources is a serious threat to the environmentand the development of the country as a whole. The environmental laws need to be oriented properly with adequate sanctionsto tackle the impacts mining has on water resources. The Environmental Impact Assessment (EIA) procedure needs to bestreamlined and undertaken by the Environmental Protection Agency (EPA) and not the company itself.


Sign in / Sign up

Export Citation Format

Share Document