Effect of Using Micropalm Oil Fuel Ash as Partial Replacement of Cement on the Properties of Cement Mortar

Kwangwoo Wi,Seungmin Lim,Mohamed A Ismail,Han-Seung Lee,Mohd Warid Hussin

doi:10.1155/2018/5164030

Abstract

This study investigates the effects of micropalm oil fuel ash (mPOFA) on compressive strength and pore structure of cement mortar. Various experimental techniques, such as compression test, isothermal calorimetry, mercury intrusion porosimetry, and X-ray diffraction, are performed to figure out the effect of using mPOFA as partial replacement of cement on the hydration of cement and determine its optimal replacement level to increase mechanical property of the mortar specimens. 10 wt.% of cement replacement with mPOFA is found to give the highest level of compressive strength, achieving a 23% increase over the control specimens after 3 days of curing. High K2O contents in mPOFA stimulate C3S in cement to form C-S-H at early ages, and high surface area of mPOFA acts as a nucleus to develop C-S-H. Also, small mPOFA particles and C-S-H formed by pozzolanic reaction fill the pores and lead to reduction in large capillary pores. In XRD analysis, a decrease in Ca(OH)2 and SiO2 contents with age confirmed a high pozzolanic reactivity of mPOFA.

Highlights

Further improvement of the fineness through an additional grinding process can solve the issue, after which the unburned carbon can be removed by drying the Palm oil fuel ash (POFA) in an oven at 500°C [25, 27]
POFA was produced by the combustion of palm oil kernel shells and palm oil fibers at a palm oil mill, which is located in Johor, Malaysia. is POFA powder was dried in an oven at 110 ± 5°C for 24 h and passed through a 300 μm sieve to remove coarse particles. e under-sized powder was further ground until 90% passed through a 45 μm sieve according to ASTM C618 [36]. is finely ground POFA is hereafter referred to as mPOFA
When mPOFA is replaced with cement at certain levels, the small mPOFA particles fill the pores between cement particles, thereby affecting the development of compressive strength [28, 34]

Summary

Introduction

Further improvement of the fineness through an additional grinding process can solve the issue, after which the unburned carbon can be removed by drying the POFA in an oven at 500°C [25, 27]. There is still lack of studies about the hydration properties and reactivity of very fine, micro-POFA (mPOFA) in a cement matrix. E specimens with an incorporation of 10% mPOFA by weight (POFA10) consistently produce the highest compressive strength, with a 33% increase over the control at 28 days of curing.

Results

Conclusion