Upgrading strategies for effective utilization of biogas

Production of biogas is based on anaerobic digestion of different renewable raw materials including human, animal, agricultural, industrial, and municipal wastes. In addition to methane content, biogas contains carbon dioxide along with water vapor, hydrogen sulfide, ammonia, and depending on the raw materials siloxane can be present. Thus, different purification and upgrading strategies are necessary in order to enhance the methane content; this review presents some of the upgrading technologies for practical removal of major contaminants in biogas. Recent development in membrane technology with high selectivity and permeability could serve as a boost in search for the most efficient biogas upgrading process capable of meeting the requirements for its use in vehicle fuel as well as incorporation in the natural gas grid

Framework of the Existing Patterns of Residential Segregation and Housing Quality in Nigeria

Residential segregation, the spatial separation of population sub-groups within a given geographical area, is a phenomenon which is prevalent in both developed and developing countries like Nigeria. This study sought to contribute to existing knowledge by reviewing the existing patterns of residential segregation and housing quality in Nigeria, and developing a framework for the existing patterns of residential segregation and housing quality. The study established that the existing residential segregation patterns are based mainly on religion, ethnicity, age and income; and the factors responsible for residential segregation in the study area are individual and aggregate socioeconomic characteristics, individual preference/taste/choice of neighbourhood and political/institutional factors. While the indicators of housing quality in the study area are building design, type of roofing and wall materials, condition and age of buildings, the type of internal facilities and the source of lighting. And the framework showed that there is a relationship between the factors responsible for residential segregation and housing quality in the study area. Keywords: Framework, Patterns, Residential Segregation, Housing Quality, Bauch

An evaluation of safety risk factors during installation and dismantling of tower cranes in construction sites

The construction industry plays a central and significant role in the economy of any nation. One of the major reasons for ineffective project delivery in the Nigerian construction industry is the improper assessment of risk factors. The industry however is currently facing a lot of challenges which include constant increase in the rate of accidents on construction sites which could be dueto ineffective safety management as construction companies are usually interested in maximizing their profit in order to secure funds for new investments, and cover possible expenses associated with the occurrence of risk factors during construction. Installation anddismantling of tower crane had been previously looked at as a general safety issue until, recent research showed that about 69% of accidents related to tower cranes in Korea from 2001-2011, occur during installation and dismantling process. In view of this, this paper aimed at evaluating safety risk factors during installation and dismantling by determining their probability of occurrence and degree of impact with a view to establishing the most significant ones. This is why a well-structured questionnaire was designed to collect data with respect to their probability of occurrence and degree of impact using a 5 point Likert scale. Responses from the administered questionnaire and interactions were collated, interpreted and analysed using descriptive statistics (mean) and results presented in tables. Results showed that abrasion (wear and tear of components such as bolts, nuts, or pins) is the most probable factor with a mean value of 3.63. Fracture of a wire rope during dismantling had the highest degree of impact with a mean valueof 4.63. The research concluded that fracture of a wire rope during dismantling and abrasion (wear and tear of components such as bolts, nuts, or pins) are highly affecting factor on safety during installation and dismantling. Adoption of a preventive maintenance strategy or routine check on the tower crane parts and components could help minimize the probability of occurrence and impact of the safety risk factors on site. Keywords: Accident, Hazard, Safety risk, Tower crane, Probability, Construction industry.&nbsp

Ethno-Religious and Socio-Economic Backgrounds as Indicators of Residential Accommodation Preference in Jos Metropolis

Location is among the main determinants of residential property value. It has been realised that location could either be tangible or intangible in nature. Tangible location attributes are those factors of location that are visible in nature and include accessibility, neighbourhood characteristic, structural features and the likes. On the other hand, intangible location factors are those attributes of location that are invisible in nature. They include race, crime, safety, religious inclination, cultural identity, native inclination, security, ethnic background, indigene ship, apartheid, violent free areas, socio-economic background, and violent prone areas and. In Jos today, people do not just take accommodation in any part of the town of their fancy. They have to do extensive research to be certain whether the area is safe. Data were collected by interviews, self-administered surveys through questionnaire and direct observation. A total of 1000 questionnaires were administered to the respondents. 876 valid responses were used to analyse the information. Descriptive and inferential statistics were employed to interpret and explain the associations found among the data. In essence theoretical, statistical and illustrative methods were employed in data analysis because of their relevance to the data generated from the research. The research findings revealed that majority of the respondents in the study area have not attained high western and religious education. Based on the above finding, it can be understood that crisis is being triggered by ignorance. It has also been discovered that most of the respondents administered with the questionnaires and interviewed are males. This is another reason why the crisis is persisting because males are the vanguard of conflict. The research found that most of the respondents are low income earners. This is also among the reasons why the people resort to violence in order to meet their daily demands and needs. The implication of the intangible location attributes could be felt in the emerging residential relocation, segregation and mobility, displacement of people, variation in land and landed property values and the likes. When carrying out feasibility and viability appraisal, attention must be given to the issue of intangible location attributes. Keywords: Ethnicity, Religion, Residential Accommodation, Socio-economic Background and Violenc

The Emergence of Dynamic Residential Property Values Owing to Violent Ethno-Religious Conflicts in Jos

The previous models of landand landed property value indicators are of two types, viz: tangible andintangible location attributes. In the case of Jos, the intangible attribute oflocation is the prime mover of residential property value indicators in areasthat are prone to violence while tangible location attributes are the mainfactors that determining real estate value in violent free areas as indicatedin the findings of the study.Socio-economic background (level of education, income, occupation, gender,religion, household size, indiginity and the likes) of Jos residents played avital role in triggering the crisis which eventually influence the values ofresidential properties in the study area. A combination ofself-administered questionnaires and semi-structured interview were deemed mostsuitable as data collection tools for this research due to the advantagesobtained from both approaches.A total of 1000 questionnaires were administeredto the respondents. Out of 1000 questionnaires administered to the respondents,876 valid responses were used to analyse the information pertaining to theeffect of intangible location attributes on residential property value in Joscity. Stratified random sampling was also adopted in order to generate datafrom the professional estate surveyors and valuers. Out of 30 firms, 10 werechosen and 120 questionnaires were administered to them, that is, 12 for eachfirm. However, out of 120 questionnaires administered to the professionalfirms, only 110 were retrieved back. . Most of the data presented using simple percentage distribution tableswere also complimented with the aid of complete theoretical analysis for somedata that are not quantifiable in nature. The research found that highestdemand for residential property was found along the inner city of Jos by theMuslims because this is the area where Muslims are in the majority which withinthe central part of the study area. It was also discovered that the outskirt ofthe city witness high influx of Christians who have sold their houses in thepredominately Muslims areas. There is a proliferation of squatter settlements,suburbs, squalid areas, ghettos and slum areas in the outskirts of Jos. Thefindings of this research is, therefore, not in conformity with the findings ofsome researchers who challenges all the existing models of residential propertyvalue by looking at safety as another indicator of land and landed propertyvalue. This research however negates this assertion because safety or securityof life and property is not a different phenomenon inters of determining thevalues of residential property but rather is among the intangible location attributesas indicators of residential property value. There is a need on the part of theinvestors and property developers before embarking into building constructionto take into consideration intangible or invisible factors of location in orderto avoid wasting of capital in the study area. When carrying out feasibilityand viability appraisal, attention must be given to the issue of Intangiblelocation attributesKeywords: Conflict, Ethno-religious Violence, ResidentialProperty Value, Residential Mobility and Residential Segregatio

The Segregated City of Jos and Its Resultant Residential Property Value Pattern

Residential segregation could be regarded as a process whereby two or more distinct communities who formerly lived together separate from one another due to many factors. Residential segregation is not only applicable to small communities but rather to a larger region. As a result of the ongoing civil unrest that engulfed the city of Jos, there has been a process of residential mobility and relocation among people of different faith. Stratified random sampling was employed in order to generate data from both Muslim’s and Christian’s residential neighbourhoods. A combination of self-administered questionnaires and semi-structured interview were deemed most suitable as data collection tools for this research due to the advantages obtained from both approaches. A total of 1000 questionnaires were administered to the respondents. Out of 1000 questionnaires administered to the respondents, 876 valid responses were used to analyse the information pertaining to the effect of intangible location attributes on residential property value in Jos city. Most of the data presented using simple percentage distribution tables were also complimented with discussion and narration for data that are not measurable in nature. Research findings uncovered that intangible location attributes play a major role in determining the value of residential accommodations in the study area. Land and landed property value could be ascertained through many indicators as revealed by the existing literatures. Relating this to rental values of residential properties, it was found that the rental values of such properties maintains a steady upward increase since when this conflicts started in the study area. The implication is that the intangible location attributes have direct influence on rent passing and sales value on residential properties in the study area. Keywords: Property Value, Residential Pattern, Residential Mobility, Residential Segregation and Violenc

Socio-Economic Characteristics of Households Determining Housing Satisfaction in Bauchi Metropolis, Bauchi State, Nigeria

Life satisfaction and housing quality are inextricably linked, and socio-economic factors have an impact on both. Low income families in poor quality housing thus bearing the impact of income-related deficits with housing satisfaction. There is potential call for lower-income families to make more frequent housing adjustment in order to be content with less-than-ideal living conditions. In Bauchi, it has been observed that socio-economic characteristics of an individual translates into his earning, thereby influences his choice of location and housing satisfaction. This study's goal was to determine examining the impact of socio-economic characteristics of households on housing satisfaction in the study area. The study employed a quantitative methodology descriptive survey. 380 household heads received a questionnaire, of which 258 were recouped and used for data analysis. Households were surveyed employing stratified random sampling to gather data on the socio-economic characteristics of the households and satisfaction with environmental and physical characteristics. To determine the symbolic importance of the various elements, the gathered questionnaire was subjected to ordinal regression and descriptive statistics. According to the research findings, household’s satisfaction is correlated with their housing. There is significant link between socio-economic indicators and households’ housing satisfaction in the study area. The socio-economic factors in the study area that had a significant impact on housing satisfaction were gender and farming as a form of occupation. The government was advised to build the social facilities that are needed, repair the ones that are in bad shape, and implement the development control requirements as soon as possible

Iron Ore Tailings as Partial Replacement for Fine Aggregate in Concrete Production – Review

Normal River sand is one of the major components of concrete, generally termed fine aggregate. A large volume of sand is needed annually for construction work globally. Mining or extraction of sand from the river bed, ocean beds, beaches, and inland dunes is accompanied by several problems such as; lowering of the water table, sinking of bridge piers and erosion of river bed and instability of river bed on the environment, etc. To decrease these environmental impacts and the cost of conventional fine aggregates, alternative materials like mining waste have been studied by several researchers to replace partially fine aggregates in concrete production. Iron ore tailings (IOT) are one of the mining wastes obtained from the beneficiation process of iron ore concentrates. This paper presents an overview of the work carried out on the use of IOT as a partial replacement of fine aggregate in concrete and its effects on the workability, mechanical, and durability properties of concrete

Statistical optimization of ethanol-based biodiesel production from sludge palm oil using locally produced candida cylindracea lipase

Face centered central composite design was used to optimize the enzyme loading, reaction temperature and mixing speed of sludge palm oil (SPO) transesterification reaction using locally produced Candida cylindracea lipase. The developed quadratic model was found to be significant at p < 0.05. The highest biodiesel yield of 57.5 % (w/w SPO) and 15.22 % free fatty acids (FFA) conversion to biodiesel with coefficient of determination R2 of 0.91 and 0.93, respectively were obtained at enzyme loading of 0.4 U/g SPO, 41 °C and 250 rpm mixing speed. Enzyme loading (U/g) gave little effect on the %FFA conversion to biodiesel and total biodiesel yield compared to temperature and mixing speed due to high FFA and water content, thus further studies are required for improvement. The study shows the low cost SPO and locally produced lipase have a promising potential in the utilization of waste for low cost biodiesel production

Assessment of Bioplastic Producing Potential of Bacillus subtilis using Some Agricultural Residues as Carbon Source

This study was carried out to assess the bioplastic producing potential of Bacillus subtilis using a variety of pretreated agricultural residues. Four agricultural residues (rice husks, molasses, bagasse, and corn cobs) were subjected to acid, alkaline and oxidative pretreatments using standard procedures. Polyhydroxybutyrate (PHB) produced was extracted using chloroform precipitation and quantified spectrophotometrically. The PHB production (g/L) for acid, alkali and hydrogen peroxide pretreatments where (n = 3) were: 1.52±0.02, 1.82±0.01, and 1.70±0.01 for rice husk; 1.82±0.01, 1.52±0.02, and 1.69±0.01 for molasses; 0.87±0.06, 1.10±0.10, and 0.96±0.07 for sugarcane bagasses and 0.5±0.00, 0.77±0.06, and 0.60±0.10 for corn cob, respectively. The maximum bioplastic yield of 63.94±2.59% was obtained in alkali pretreated corn cobs, while the lowest yield of 50.33±0.76% was found in acid pretreated rice husk. Thus, the findings in this study revealed that agricultural residues could be explored for PHB production in the presence of potential microbial strains due to their abundance, high carbon content, limited inhibitory effect and cost effectiveness