106 research outputs found
Design and operating parameters of a fulidized bed for the combustion of municipal solid waste using standpipes air distributors
Hydrodynamic studies and combustion of simulated and actual municipal solid waste were carried out in a fluidized bed system. A wide range of parameters was investigated in hydrodynamic study after which the optimum parameters were implemented in the combustion studies. A newly fabricated standpipes air distributor (primary air inlet) was designed based on findings of the optimum orifice diameter, orifice distance and distance between pipes. Orifice diameter, orifice distance and distance between pipes of 3 mm, 10 mm and 70 mm were used in the hydrodynamic studies of circular and rectangular columns (CHS and RHS). The operating parameters investigated in the CHS and RHS included the effect of sand sizes and aspect ratios on the fluidization profile. Standpipes air distributors having the same orifice diameter and distance but with a wider pipe distance of 200 mm were used in the hydrodynamic studies of a bigger rectangular (big scale) column. Different air flow strategies were implemented to ensure good mixing between sand and samples and to investigate the penetration of the incombustibles into the sand bed. Parameters studied in the combustion of municipal solid waste included the effect of fluidizing velocity and air factor on the combustion profile in the bed as well as the freeboard region with standpipe air distributor design and dimension established from the hydrodynamic studies of a bigger scale rectangular column. Findings from the CHS and RHS showed that sand particles with mean size of 0.34 mm performed good fluidization profile compared to other coarser sand sizes. The ratio of the bed height over diameter of column (Dc) for good fluidization was determined at cDH?for the circular column whereas the ratio of the bed height (H) over the length (L) of column was observed at H<L for the rectangular columns. A two side air flow was seen as the best air flow strategy for good mixing in a bigger rectangular column. The range of fluidization number and air factor for the combustion of simulated municipal solid waste in a rectangular fluidized bed combustor was 5 – 7 mfUin which 5 mf U was found to be the optimum with air factor of 0.8 (primary air). Air factor of 0.4 (secondary air) was observed to show good temperature profile in the freeboard region for the combustion of municipal solid waste. The optimum total combined air factor for the combustion of municipal solid waste was 1.2 in which inlet primary air factor and inlet secondary air factor were 0.8 and 0.4, respectively
Geometrical design of stand pipe air distributors for the combustion of municipal solid waste in a fluidised bed
The new geometrical design of stand-pipe air distributor for the combustion of the municipal solid waste was presented. The new design of the air distributors enables penetration of incombustible and unburnt carbon through opening between the air distributors, thus providing easy maintenance work. The fluidized bed experimental rig was constructed using Perspex column in which air was supplied through the distributors below it. In order to establish the final geometrical design of the air distributors, several design parameters were investigated. The effect of orifice size, distance between orifice and distance between distributor pipes on the fluidization behaviour were studied. Investigation on the effects of various orifice sizes of 1.5 mm, 2 mm, 3 mm, 4 mm and 5 mm showed that the 3 mm orifice size exhibited the most stable fluidization behaviour. Investigation on some selected orifice distances of 10 mm, 20 mm, 30 mm and 40 mm also found that the 10 mm orifice distance exhibited stable growths of bubbles. Various pipe distances of 30 mm, 40 mm, 50 mm, 60 mm and 70 mm were also investigated and the most suitable pipe distance was 70 mm
Characterization of the fuel properties of ananas comosus leaf for thermal application
In recent years, the demand of energy in Malaysia increases significantly. It is generally accepted that the source of fossil fuel will be depleted in future since it is classify as non-renewable energy. Consequently, Malaysia is a country rich in biomass energy resource that easily can be converted into biomass fuel for thermal applications such as AnanasComosus leaf for clean energy production. This study is aimed to characterizing AnanasComosus leaf of N36 hybrid, selected from between ‘Gandul' (Spanish) and the ‘Smooth Cayenne'.The physical and chemical properties of the AnanasComosus leaf were analyzed using ultimate analysis, proximate analysis and heating value. The thermal decomposition behavior of the fuel was determined through thermogravimetric analysis (TGA). From the result obtained, the parameter of ignition temperature (Tign) 322°C and maximum temperature (Tmax) 367°C, and final temperature (Tf) 810°C were gathered. The total weight of the fuel remaining at Tfwas 14.01% signifying that the conversion of the fuel will result in 85.99% conversion
Socio-Technical System as Factors and Influences in Form Design Development
Since digitalisation in the cyber-physical system has taken over design development, researchers attempt to improve the approach to new product development including brand recognition. This research attempt to determine the design strategy based on syntactic design meaning in analysing the visual through design formulation, design treatment and design standard inline socio-technical system. The concept of digitalisation design scenario, the methodology was developed by observational study, laboratory study and interview to analyse designer integrates with the strategy of design analysis. The design analysis was approachable to determine the design representation and potentially generalised the characteristic of product design and consumers' psychological preferences toward product forms.
Keywords: Socio-technical system; form development; design thinking; influence factors
eISSN: 2398-4287 © 2022. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open-access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under the responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians), and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.
DOI: https://doi.org/10.21834/ebpj.v7iSI7.379
Guidelines for process safety hazard assessment based on process information
In any new chemical process development and design, process safety is a critical aspect to be considered besides economic and technical feasibility of the manufacture of the product. A lack of proper hazard assessment during the design phase may later result in accidents with disastrous consequences to workers, the public as well as the environment. Many methods have been introduced to qualitatively and quantitatively assess the safety level of processes. Despite the availability of a large amount of methods, a systematic framework that details guidelines for hazard identification, risk assessment, safety measure design, and safe critical decision-making is still missing. To address this issue, the main objective of this study was to propose a systematic framework that outlines comprehensive guidelines for assessing the safety performance of processes based on information from the piping and instrumentation diagram (P&ID). Apart from proposing the framework, appropriate strategies for minimizing safety hazards and risks are also recommended. In addition, the user is assisted in selecting the most appropriate assessment method according to his or her needs and the scope and constraints of the assessment. A case study is presented to illustrate the application of the proposed framework
Guidelines for Process Safety Hazard Assessment Based on Process Information
In any new chemical process development and design, process safety is a critical aspect to be considered besides economic and technical feasibility of the manufacture of the product. A lack of proper hazard assessment during the design phase may later result in accidents with disastrous consequences to workers, the public as well as the environment. Many methods have been introduced to qualitatively and quantitatively assess the safety level of processes. Despite the availability of a large amount of methods, a systematic framework that details guidelines for hazard identification, risk assessment, safety measure design, and safe critical decision-making is still missing. To address this issue, the main objective of this study was to propose a systematic framework that outlines comprehensive guidelines for assessing the safety performance of processes based on information from the piping and instrumentation diagram (P&ID). Apart from proposing the framework, appropriate strategies for minimizing safety hazards and risks are also recommended. In addition, the user is assisted in selecting the most appropriate assessment method according to his or her needs and the scope and constraints of the assessment. A case study is presented to illustrate the application of the proposed framework
Investigate the Potential Renewable Energy of Microalgae Spirulina sp Using Proximate Analyzer, SEM-EDX, and Thermogravimetry
Microalgae Spirulina sp which has been cultivated by the Brackishwater Aquaculture Development Center, Situbondo Indonesia were tested for their potential energy performance using proximate analyzer, SEM-EDX, and thermogravimetry. The proximate analyzer showed volatile matter (VM), fixed carbon (FC), moisture, ash content (AC), total sulfur of microalgae Spirulina sp 68.15, 12.57, 11.22, 8.06, and 0.67 (wt%, ar), respectively, and the gross calorific value (GCV) is 4971 kcal/kg (dry basis). SEM-EDX test showed the morphology and chemical content of Spirulina sp. The content of microalgae Spirulina sp is dominated by carbon (C) and oxygen (O), then followed by chlorine (Cl), sodium (Na), potassium (K), sulfur (S), magnesium (Mg), and phosphorus (P). Thermogravimetry pyrolysis test of microalgae Spirulina sp resulted thermogravimetry (TG) analysis and derivative thermogravimetry (DTG) analysis curve, which is divided into three different steps. The moisture of microalga Spirulina sp was vaporized at the first step, started at 27°C, and finished at 173°C with a decomposed mass of about 13.81% of the total initial mass. The second step began at the end of vaporize moisture at about 173°C and ended at around 618 °C. The gasification process occurred in volatile matter content and resulted mass loss of about 57.9% of Spirulina sp total mass. The last step showed the process of gasification of residual substances, started at the end of the volatile matter step, 618°C, and stopped at 995°C with a decomposed mass of 24.6% from total mass
Carbonized rice husk and cocopeat as alternative media bed for aquaponic system
The study evaluates the suitability of carbonized rice husk and cocopeat substrates as alternative media bed in aquaponics unit for cultivation of red Nile tilapia and Gynura procumbens. Area occupied by the aquaponics unit is about 4.5 m2 and it was operated under equatorial climate conditions. Various substrates namely lightweight expanded clay aggregate (LECA), cocopeat, carbonized rice husk and a mixture of cocopeat-rice husk at ratio 1:1 were prepared using polybags for growing of the longevity spinach. The resultant effects from fish cultivation and plants growth on the water qualities and nitrification efficiency of the aquaponics unit were reported. The aquaponics unit were operated for twelve weeks and the values of pH, temperature, and dissolved oxygen level were measured to be within the range of 6.4-6.9, 27.7-29oC, and 5.5-7 mg·L-1, respectively. Survival rate for fish was 98% with specific growth rate (SGR) and food conversion ratio (FCR) of 6.9% per day and 1.13, respectively. Nutrient deficiency was not evident and plants showed healthy growth with harvest yield ranging between 3.6 and 3.9 kg·m-2. Results attained signified the suitability of utilizing carbonized rice husk and cocopeat as alternatives media bed compared to commercial media bed such as LECA
Human factors issues in basic offshore survival and emergency training for platforms in tropical water
The presence of human factors in escape and evacuation on offshore installations has been studied by many researchers and engineers. The studies lack of analysis on human factors in the design of emergency equipment to increase chances of success during emergencies. This paper presents the survey on basic offshore safety and emergency training for individuals working on platforms in tropical water. The main objective of the research is to identify human factors issues faced by individuals performing escape and evacuation on offshore platforms in tropical water. A set of questionnaires was distributed to 16 individuals participating in the Tropical Basic Offshore Safety Induction and Emergency Training (T-BOSIET) at Terengganu Safety Training Centre, Kemaman
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