Table of Contents

Evaluation of Procurement in Public Building Construction Projects

Delivery

Abdulkadir, Abu Lawal                                                                                    1-20

Mechanism of Carbonation in Concrete and Its Prediction –

A Review

Alhassan, Yunusa Aminu                                                                                 21-60

A Review of the Design and Analysis of a Fire Tube Boiler

Abdulrauf A. IbrahimGhali M.Jibril andBucham Osang                                 61-79

Investigation of Heat Transfer Analysis in A 4- Pass Fire Tube Boiler

Rachel Ugye Kantiok Obadiah andAdaokoma Apasi                                                 80-91

Design and Fabrication of a Cupola Furnace for Material Processing

Kantiok Obadiah, Rachel Ugye and Abubakar N. Mohammed                       92-108

INVESTIGATION OF HEAT TRANSFER ANALYSIS IN A 4- PASS FIRE TUBE BOILER

¹Rachel Ugye ² Kantiok Obadiah and ³  Adaokoma Apasi 

 Department of Mechanical Engineering,

College of Engineering , Federal polytechnic. Kaduna.

ABSTRACT

The efficiency of a boiler the ratio of heat utilized in producing steam and heat liberated in the furnace, but the heat liberated in the furnace is always greater than heat utilized in the boiler ,the differences that exist between these forms of  heat is known as the heat losses in the boiler .This paper analyses the various heat losses as it affects the efficiency of the fire tube boiler located  at the department of Mechanical Engineering, Kaduna Polytechnic. Emphasis was made on the reason for these losses and ways to minimize it.

A REVIEW OF THE DESIGN AND ANALYSIS OF A FIRE TUBE BOILER

Abdulrauf A. Ibrahim ¹ Ghali M.Jibril² andBucham Osang³

^1&3Department of Mechanical Engineering, College of Engineering, Kaduna Polytechnic

²National Board for Technology Incubation, Technology Incubation Centre Kaduna.

E-mail:abdrauf35@yahoo.com

Abstract

A boiler is a closed vessel in which water under pressure is transformed into steam by the application of heat. In the boiler furnace, the chemical energy in the fuel is converted into heat, and it is the function of the boiler to transfer this heat to the contained water in the most efficient manner. The boiler must be designed to absorb maximum amount of heat released in the process of combustion. This heat is transferred to the boiler water through radiation, conduction and convection. The relative percentage of each is dependent upon the type of boiler, the designed heat transfer surface, and fuel. This review from related literature focus on the design and analysis of a fire tube boiler which are internally fired, horizontal and natural circulation boiler. Example is the   Lancashire boilers which are reliable and bear over load. However, they are bulky and initially raise steam very slowly.Efficiency of the boiler is about 65%–70%. This research discuss the increase in the efficiency of a fire tube boiler through enhancing the heat transfer rate in the boiler tube. Due to economic and environment demand, engineers must continuously focus on improving the efficiency of the boiler emission reduction through usage of high grade fuel and incorporating heat exchangers that will utilize the flue gasses.

MECHANISM OF CARBONATION IN CONCRETE AND ITS PREDICTION – A REVIEW

Alhassan, Yunusa Aminu

Department of Civil Engineering,

Federal Polytechnic Idah, Nigeria

Email: alhassanay@gmail.com

Abstract

This paper examines the process of carbonation in concrete as while as factors that influence carbonation progression in concrete. Quantification of carbonation process in an inland environment and basis for the derivation of the carbonation progression rate in concrete were also reviewed. The paper then x-rayed extensively existing carbonation prediction models and finally it proposed an approach for the development of carbonation prediction model for reinforced concrete structures located in an inland environment.

DESIGN AND FABRICATION OF A CUPOLA FURNACE FOR MATERIAL PROCESSING

¹Kantiok Obadiah, ²Rachel Ugye and ³Abubakar N. Mohammed

Department of Mechanical Engineering,

College of Engineering, Federal Polytechnic Kaduna.

E-mail:abdrrrauf35@gmail.com

Abstract

Foundry cupola furnace capable of melting cast iron to the desired pouring temperature was designed, constructed and tested. Coke which is the by product of coal is used as a fuel, a centrifugal blower that delivers air at the required pressure and flow rate for proper combustion to take place inside the furnace. To provide greater utilization of heat inside the furnace, the lining of the furnace was performed with Alumina and fire clay refractory that can withstand the operating temperature and thermal stresses arising from the pressure and temperature developed inside the furnace. Analysis such as that of buckling load on the stands, thermal stresses developed in the cupola shells, load on the bolts were carried out so that, careful selection of materials is performed. The main focus in this Design is to improve continuous working hours, reducing preparation time, reducing losses in melting, reducing slag formation and to increase the combustion efficiency of coke and overall productivity and to improve the quality and Mechanical properties of steel using Cupola

EVALUATION OF PROCUREMENT IN PUBLIC BUILDING CONSTRUCTION PROJECTS DELIVERY

Abdulkadir, Abu Lawal

Department of Building Technology

College of Environmental Studies

Hassan Usman Katsina Polytechnic, Katsina.

E-mail: aalawal3@gmail.com

Abstract

The paper looked at procurement alternatives as essential cost saving measure in construction contracts, and the essence of contractual options in Nigeria as a developing Nation.  A statistical scenario herein is drawn based on the responses of key independent professionals who are most concerned with  building construction contract procurements in respect to key critical variable factors to rationale procurement. The respective agreements, and otherwise their dichotomy to these variable critical factors, were analyzed and discussed.  The scenario, like in a consensus decision making problems using fuzzy elements, is also based on their ranked ordinal data through structured questionnaire. This can be adopted and used to test the efficacy of procurement systems for local councils, state and federal government project execution in Nigeria, using Kendall’s tau coefficient of concordance, and chi-square (x²). From the analysis it is found that the Kendall’s coefficient is 0.0032 and chi square test yielded 5.472 at 0.05 significant levels indicating no significance to null hypothesis. Analyzing such responses to rationale procurement in construction very important, as contract procurement has become the focus of International agencies for projects financing, good leaders, and policy makers in the less developed countries. The identified contentious areas when rectified would facilitate immensely in plugging sources of fund leakages, and wastage. Further step can be taken using veritable structured questionnaire to obtain responses of employee in both the private and public sector, with the view of ascertaining whether the right procedures are adopted in projects execution. The need for the exigency of locking horns with inefficiency and leakages in our procurement system is necessary, and some remedial measures are suggested.