Mahmood Saleem

Emissions of NOx, SO2, and CO from Co-Combustion of Wheat Straw and Coal Under Fast Fluidized Bed Condition

Fuel diversity and reduction in pollutant emissions are driving the increased utilization of CO2 neutral biomass. Effects of operating conditions, such as bed temperature; excess air ratio; and secondary to primary air ratio on emissions of NOx, SO2, and CO for burning different blends of wheat straw and Salt Range coal under fast fluidized bed conditions in a pilot scale test facility, are reported in this study. Emissions of NOx were found to decrease with an increase in wheat straw ratio and secondary to primary air ratio. SO2 and CO emissions were observed to decrease with an increase in excess air ratio and wheat straw ratio.

In‐situ measurement of dust deposition on bag filters using stereo vision and non‐rigid registration

Purpose – The goal is to perform an in‐situ measurement of dust layer thickness on bag filters.Design/methodology/approach – Presents a machine vision system in terms of hard‐ and software which is capable of obtaining the relative height difference of a cloth filter surface in different states of operation. The measurement process starts with a stereo reconstruction of filter surface patches. The patches are aligned to form a continuous model using the iterative closest point algorithm. Models acquired at different states of operation are registered using thin plate spline interpolation and afterwards subtracted from each other to obtain the relative height difference.Findings – Relative thickness measurement is possible with an accuracy ranging from 50 to 300 μm, depending on the operational states.Research limitations/implications – In‐situ measurement of dust deposition is a new tool for examining the behaviour of commercial bag filters.Practical implications – Provides the foundation for a system mea...

Effect of operating parameters on production of bio-oil from fast pyrolysis of maize stalk in bubbling fluidized bed reactor

Abstract The yield and composition of pyrolysis products depend on the characteristics of feed stock and process operating parameters. Effect of particle size, reaction temperature and carrier gas flow rate on the yield of bio-oil from fast pyrolysis of Pakistani maize stalk was investigated. Pyrolysis experiments were performed at temperature range of 360-540°C, feed particle size of 1-2 mm and carrier gas fl ow rate of 7.0-13.0 m3/h (0.61.1 m/s superficial velocity). Bio-oil yield increased with the increase of temperature followed by a decreasing trend. The maximum yield of bio-oil obtained was 42 wt% at a temperature of 490°C with the particle size of around 1.0 mm and carrier gas flow rate of 11.0 m3/h (0.9 m/s superficial velocity). High temperatures resulted in the higher ratios of char and non-condensable gas.