P.A. Kuale and S.O. Otuagoma

Department of Mechanical Engineering Technology 

Rufus Giwa Polytechnic, Owo, Ondo State

SUMMARY

Many electric energy consumers’ premises are not metered. Accordingly estimated bills are sent to them. In some cases, meters are not read, but bills are still sent to consumers. This study showed that the estimated bills by PHCN sent to consumers, without meters is on the high side. It is very necessary for consumers to be billed for the actual energy consumed. That PHCN should ensure that all consumer premises are metered and accordingly when meters are not available PHCN should examine our work and do their own study and come to accurate figures for billing consumers.

DETERMINATION OF THE RHEOLOGICAL PROPERTIES OF DRILLING FLUID FROM LOCALLY SOURCED CLAY FROM VARIOUS GEOGRAPHICAL AREAS

Ajugwe  C; Oloro. J  and Akpotu. D.

Department of Petroleum Engineering

Delta State University, Oleh Campus

E-mail: joloroeng@yahoo.com

ABSTRACT

The rheological formulation of our locally sourced bentonite clay in substitute for the imported foreign bentonite clay was carried out by the comparative analysis of the parameters of the local mud with the stipulated API standard values to ascertain the level of compliance in drilling operation. The local muds P^H values responded positively on beneficiation with 1.0g of potash, the modification raised the muds P^H values to fall within the standard range of 9.5 to 12.5. The viscosity of the local muds was seen to be slightly below the standard requirement of 30cp, but appreciated favorably to the standard requirement when beneficiated with 1.0g of drispac. On beneficiating the foreign aqua gel bentonite muds, with the same quantity of additives used on other mud samples, there was an excessive abnormal increase in its viscosity for instance the viscosity of 17.5g of the foreign mud was drastically raised from 17.1cp to 210.5cp at 600 dial reading. It was obvious that most of the prepared local  mud samples parameters such as the sand percentage composition, power law index, density, marsh funnel viscosity, etc met the minimum required specifications,  while other few parameters such as the theological properties, needed some additive treatment for favorable comparison with the foreign clay mud properties. Therefore, the utilization of these clays for any industrial application will pose no harm to surface and surface facilities and will in no turn represent a value added to the Nigeria economy by the total prevention of the important of high quality activated foreign bentonite clay. Tests and analysis were carried out on Local Clay samples obtained from a town in delta state, imo state and the foreign commercial bentonite. This research is to evaluate the performance of the Local clay samples for drilling operations in Nigeria. The rheological and the thixotropic properties as well as other parameters of the Local clay mud was seen to have improved, but however, when beneficiated with chemical additives of different concentrations, there was an increase in the overall parameters of the Local mud samples, making them ideal for any industrial application as their parameters met with the stipulated standard specifications of API, OCDA.

ELECTRICAL PARAMETERS ESTIMATION OF SOLAR PHOTOVOLTAIC MODULE

¹ I. Mustapha; B. U. Musa¹; M. K. Dikwa² and M. Abbagana¹

¹Department of Electrical and Electronics Engineering, University of Maiduguri, Nigeria

 ²Department of Computer Engineering, University of Maiduguri, Nigeria

E-mail:ibrahimmassa@yahoo.com, musa_bu@yahoo.com, mkdikwa@gmail.com, moduabbagana@yahoo.com

ABSTRACT

Environmental Weather conditions such as ambient temperature and solar irradiance have significant impact on predicting I-V and P-V characteristics of solar PV modules. Electrical parameters of solar PV modules at site of installation differ from those provided by the manufacturer due to variation in environmental conditions such as solar irradiance and ambient temperature. This paper estimates electrical parameters of a monocrystalline solar photovoltaic module (SW 250) with respect to Maiduguri weather conditions. A simple one-diode mathematical model was implemented using MATLAB script which predicts the I-V and P-V characteristics of the solar PV module based on Local Operating Conditions (LOC) i.e Maiduguri environmental weather conditions. Simulation results confirmed that electrical parameters at LOC differ slightly with that provided by the manufacturer at Standard Test Conditions (STC) and Nominal Operating Cell Temperatures (NOCT). The results show that the  short circuit current and the peak current at LOC are 8.7% and 9.5% less than that at NOCT respectively, while the open circuit voltage and the peak voltage at LOC differed by 15% and 7.5% to that at NOCT respectively. The maximum power at LOC is 17.5% less than that provided by the manufacturer at NOCT. Thus the photovoltaic module exhibited good performance in the region under study.

Keywords- Photovoltaic module, short circuit current, irradiance, temperature, open circuit voltage 

ROAD PAVEMENT FAILURE INDUCED BY POOR SOIL PROPERTIES ALONG GOMBI-BIU HIGHWAY, NIGERIA

Hijab Mahmoud¹, Zaynab A.  Belel¹ and Hadi A.  Abba²

Department of Civil Engineering, Modibbo Adama University of Technology, Yola

²Department of Civil Engineering, Kaduna Polytechnic, Kaduna State

E-mail: hijabmahmoud@yahoo.com

ABSTRACT

This article investigates highway pavement failure on critical locations due to poor soil properties along Gombi – Biu Road. Visual observation of the affected areas revealed substantial structural failure. Laboratory test results of the disturbed soil samples collected from the failed sections of the road showed that the natural soil moisture ranged from 7.0% to 15.9%, the liquid limits and Plasticity Indexes did not conform to specification. The CBR values ranged from 5.1% to 31.1% indicating poor soil or strong reduction in the strength of the soil materials used in the construction of the road. Excess fines and very low liquid limit values combined with a very low CBR value to cause the failure of the pavement at this locality. The geotechnical properties indicated substandard paving properties for Nigerian roads. Therefore, soil stabilization is suggested to improve the strength of the soil and prolong the useful life and durability of the road.

Keywords: Pavement, Materials, Failure.

DESIGN, CONSTRUCTION AND EVALUATION OF A SMALL SCALE SOLAR DRYER

¹Onigbogi I.O, Sobowale, S. Sand Ezekoma, O.S

Department of Food Technology

Moshood Abiola polytechnic Abeokuta, Ogun State

E-mail: sunsam_2003@yahoo.co.uk

ABSTRACT

The solar drying system utilizes solar energy to heat up air and to dry any food substance loaded, which is beneficial in reducing wastage of agricultural product and helps in preservation of agricultural product. Based on the limitations of the natural sun drying e.g. exposure to direct sunlight, liability to pests and rodents lack of proper monitoring, and the escalated cost of the mechanical dryer, a solar is therefore developed to cater for this limitation. This project presents the design and construction of a domestic passive solar dryer.The dryer is composed of solar collector (air heater) and a solar drying chamber constraining rack of three cloth (net) trays both being integrated together. The air allowed in through air inlet is heated up in the solar collector and channeled through the drying chamber where it is utilized in drying. The design was based on the geographical location which is Abeokuta and meteorological data were obtained for proper design specification. The dimensions of the dryer is 94cm x 45cm x 101cm / 20cm (length x width x height). Locally available material were used for the construction, chiefly comprising of wood (gmelina), glass, aluminum metal sheet, copper and net cloth  for the trays. The optimum temperature of the dryer is 50.50^OC with a corresponding ambient temperature of 34.50^o C. The moisture content removal of 43.2% and 40.6% in maize and plantain respectively using the solar dryer was achieved as against 28.2% and 27.89% in maize and plantain using the sun drying method and indication 15.0% and 12.71% difference respectively, the rapid rate of drying in the dryer reveals its ability to dry food items reasonable rapidly to a safe moisture.

Keywords: Solar dryer, Moisture loss, Design and Construction, Maize and Plantain

APPLICATION OF PROJECT MANAGEMENT TECHNIQUES IN A CONSTRUCTION FIRM

A. O. Odior

Department of Production Engineering

University of Benin, Benin City, Nigeria

E-mail: waddnis@yahoo.com

ABSTRACT

An important aspect of life cycle management in construction project development is project planning and control. There are five elements in project planning techniques: project planning, monitoring, reporting, collection of statistics and re-planning. The study presents the techniques and strategy for planning and controlling project activities, development of the network diagram and determination of critical path using the critical path method. The probability of meeting up the stipulated time was 65 percent along the critical path and the sub-critical paths while the minimum project duration was 98 weeks.

Keywords: Life Cycle Management, Project Planning, Project Monitoring, Critical Path Method, Project Duration.