Dr. Hassan K Abdulrahim | Kuwait Institute for Scientific Research (KISR) (original) (raw)

Papers by Dr. Hassan K Abdulrahim

Desalination and Water Treatment, 2016

Qatar Foundation Annual Research Forum Proceedings, 2012

This paper aims to study a new solution for integrating Multi-Effect Distillation (MED) system wi... more This paper aims to study a new solution for integrating Multi-Effect Distillation (MED) system with
Generator-Absorber-Heat Exchanger (GAX) cycle. The absorption cycle can be used as a vapor
compressor for the MED system to improve its gain output ration. Another proposed scenario is to
utilize the vapor produced in the absorption cycle to drive the MED beside the cooling effect.
Thermodynamics and heat transfer models were implemented to evaluate the performance of the
proposed integrated system. IPSEpro, process simulation software, was utilized for this purpose. The
simulation results revealed some advantages for the integrated system compared to the conventional
MED. The results showed an increase in the GOR of the MED compared to the conventional ones.

This paper presents an overview of using solar energy in running desalination systems, called sol... more This paper presents an overview of using solar energy in running desalination systems,
called solar desalination. Solar energy can be converted directly to electric energy, which
can operate electrically driven desalting systems such as reverse osmosis (RO), electrodialy-
sis (ED), and mechanical vapor compression systems. Solar energy can also be converted to
the thermal energy that can operate the mainly used thermally operated desalination system
such as multistage ﬂash (MSF), conventional multieffect (ME), and multieffect thermal
vapor compression (ME-TVC), and emerging membrane distillation and humidiﬁcation–
dehumidiﬁcation desalination systems. The thermal energy converted from solar energy can
also be used to produce high-pressure steam running power plant producing electric power
to operate mechanically driven desalting systems, and/or extracted steam at relatively low
pressure to operate thermally driven desalting system. The main obstacle that hinders the
use of solar desalination is the initial investment cost. This paper discusses the use of the
solar desalination and calculates the investment cost to install solar desalination plants.
These include photovoltaic (PV)-driven RO system, and thermally driven MSF and ME
plants by steam directly generated by solar collectors, or by steam extracted from solar
steam power plants operated by the concentrated solar collectors. The results revealed that
PV-RO desalting system has the highest speciﬁc capital cost, among the considered systems,
because the expensive storage of the electric energy in batteries, and the fact solar energy
supply lasts about one third of the day. It showed also that using the thermally generated
energy from concentrated solar collectors operating power plant is much cheaper than using
this thermal energy when directly operating the desalination system.

The feed to all Recirculation-multi-stage ﬂash (R-MSF) desalting units in Qatar is pretreated wit... more The feed to all Recirculation-multi-stage ﬂash (R-MSF) desalting units in Qatar is
pretreated with high temperature additive, which limits its top brine temperature (TBT) to
110˚C. The daily capacity of these R-MSF units is about one Million cubic meters
(Mm3/d). These units should continue their operation through their life time,
(20–30 years). The capacity and performance of these units can be enhanced if Forward
osmosis (FO) membrane system is used as pretreatment. The FO membranes can remove
the scale constituents in the feed water and allows rising the TBT up to 135˚C, and thus
increases the capacity of these units. The viability of using FO as feed water pretreatment
to an existing operating R-MSF unit is discussed in this paper. A suggested arrangement
to use FO as MSF feed pretreatment is presented. Part of the cooling seawater leaving the
heat rejection is directed to the FO pretreatment unit as feed solution (FS). The ﬂashing
brine leaving the last stage with the maximum brine salt concentration (about 1.5 times of
the seawater feed) is directed to the FO unit as draw solution (DS) that absorbs an
amount permeate water (D) from the FS while the Ca2+, CO3, Mg2+, and SO42 are
rejected. The diluted DS enters the last stage condenser of the heat recovery section. This
arrangement allows to increase the TBT and thus the unit distillate capacity. The potential
of calcium sulfate deposite index inside MSF condenser tubes is calculated at different
TBTs and different FO recovery ratio. The calculations show that Skillman index in refer-
ence MSF (operates at TBT = 110˚C) plant is greater than one which indicates the potential
of scale deposit formation; however, antiscalant is used to disperse the crystalized scale.
The simulation results showed that the potential of scale deposit is decreased as the FO
recovery ratio increases due to the increase in divalent ions removal. The MSF can operate
at TBT = 135˚C safely without calcium sulfate scale at FO recovery ratio of 40%. On the
other hand, the increase in the FO recovery ratio, will reduce the osmotic pressure differ-
ence across the membrane which requires higher membrane surface area. The impact of
feed salinity is investigated, and the results showed that lowering the feed salinity gives

International Journal of Exergy, 2010

Desalination and Water Treatment, 2015

Recent installed power plants (PP) in Qatar and other Gulf Co-operation Countries (GCC) are usin... more Recent installed power plants (PP) in Qatar and other Gulf Co-operation Countries (GCC) are
using combined cycle (CC). The CC cycle consists of gas turbine (GT), heat recovery steam
generators (HRSG), and steam turbine (ST). In these plants, GTs produce electric power (EP)
and its exhaust hot gasses operate the HRSG to generate steam. The steam is supplied to ST
that generates more EP, and its extracted (or discharged) steam is directed to thermally
operated desalting plant (DP), e.g. multi stage flash (MSF) or multi-effect thermal vapor
compression (ME-TVC) producing desalted seawater (DW). A plant producing both EP and
DW is called co-generation power desalting plant (CPDP). The used ST type is either
extraction condensing steam turbine or back-pressure steam turbine. The MSF or ME-TVC
consumes about 280 MJ/m3 thermal energy, besides pumping energy of 4 kWh/m3 for MSF
or 2 kWh/m3 for ME-TVC systems. Because of high consumed energy, the MSF and ME-TVC
systems have to be substituted by the much more energy-efficient seawater reverse osmosis
(SWRO) desalting system, which consumes 4–5 kWh/m3 only as pumping energy. Replacement
of the MSF (or ME-TVC) with the SWRO system will ban the use of steam extracted (discharged)
to the DP; the plants produce only EP, and become single-purpose PP. This reduces
the plant overall efficiency unless major retrofitting is done by adding low pressure (LP) ST
and condenser to expand the steam that was supplied to the DP in the turbine to produce
more work. In this paper, it is suggested that the CPDP widely used in the GCC to become a
tri-generation plant producing EP, DW (by SWRO), and chilled water for district cooling
(DC). An analysis is presented for the newly suggested configuration. It showed that a
reference plant can be fitted with SWRO to replace the DP of MSF or ME-TVC and gives
almost the same DW production capacity for the identical consumed EP by the MSF units.
The process heat that was supplied to the thermal desalting units would be utilized for DC
system using an absorption cooling unit(s). Comparisons of absorption cooling with the EP
driven mechanical vapor compression refrigeration; and SWRO with the MSF desalting
systems are illustrated in this article. The benefits of using DC in the GCC are also presented.

Qatar, one of the world’s poorest countries in terms of fresh water resources, has the highest wa... more Qatar, one of the world’s poorest countries in terms of fresh water resources, has the highest water consumption per capita in the world (>500 L/day/person). The country is completely dependent on seawater desalination to meet local demands. Limited and overexploited groundwater resources (GW) are used for crop irrigation; however, due to increasing population, Qatar imports over 95% of all food. Qatar’s high volume of wastewater is currently treated using advanced technologies, often to the tertiary level. The quality of the treated wastewater (TWW) achieved allows for the water to meet standards for irrigation use; however, social factors currently inhibit this practice. This paper uses scientific, economic and technical evidence to show that TWW is a valuable and safe resource for crop irrigation that poses minimal risk to the soil, GW, and crops and is a key factor towards Qatar’s food security. Content targets the scientific community, public and policy makers.

Desalination and Water Treatment, 2015

Water security in Qatar is of main concern. Low water pricing in Qatar does reflect the real valu... more Water security in Qatar is of main concern. Low water pricing in Qatar does reflect the real value of water. The high cost of desalted seawater (DW) calculated in this paper calls for the use of more energy efficient desalting system such as the SWRO system in place of the multistage flash (MSF) and multi effect thermal vapor compression (ME-TVC) methods presently used. Both MSF and ME-TVC use thermal energy of about 270 kJ/m3 and pumping energy of 2–4 kWh/m3. In this paper, the mechanical energy equivalent to the thermal energy supplied to the MSF (or ME-TVC) systems is calculated. When added to the pumping energy, it gives the specific consumed energy of more than 20 kWh/m3, compared to 4– 5 kWh/m3 for SWRO system. Qatar’s ground water (GW) is overexploited, depleted, and quality deteriorated, and thus the demand for DW is on the rise, with the more financial burden. Moreover, DW productions mean more air and marine environment deterioration. The water subsidization by the government should be reviewed, and water demand management should be applied. Wastewater should be treated for reuse to decrease the demand on both GW and DW. The calculated costs of DW at different natural gas price are calculated, and compared with the underestimated cost reported by the government.

Desalination and Water Treatment, 2014

Forward osmosis (FO) has emerged as a method for desalting saline water and power production. It... more Forward osmosis (FO) has emerged as a method for desalting saline water and power
production. It utilizes a chemical potential difference, or a salinity gradient to permeate
fresh water through membranes. This paper investigates the feasibility of using the FO process
for seawater (SW) desalination in terms of consumed energy, capital costs, water recovery,
operation & maintenance, water quality, and the final product water cost. The study
covers FO by itself, and when combines with other desalting systems such as reverse osmosis,
multi stage flash (MSF), and multi effect distillation as pretreatment method. This paper
reviews first the principles of fluid and solutes flow in the FO membranes, concentration
polarization, the difference between the FO, pressure retarded osmosis processes, draw
solutions, and the solutes involved in these draw solutions. Then, the main characteristics
of the FO membranes and their commercial availability are presented. Previous experimental
work and a commercial plant using FO for desalination are also given. The use of FO as
pretreatment for other desalting methods is presented in light of two proposed research
projects. The first research project proposes utilizing FO as pretreatment for processing treated
wastewater and SW in one system. The second project utilizes FO as pretreatment for a
once-through MSF desalting method. The analysis proved energy reduction in the energy
consumption of both desalting systems by more than 50 and 18%, respectively.

Abstract- Qatar declared that by 2020 solar energy would produce at least 2% of its total generat... more Abstract- Qatar declared that by 2020 solar energy would produce at least 2% of its total generated electric power
(EP). The known solar power plants EP at utility scale level are concentrating solar power (using parabolic trough
collectors, linear Fresnel collector, and solar tower), photovoltaic (PV), and integrated solar combined cycle using
fossil fuel (natural gas) besides solar collectors.
EP generation by PV is reliable, clean, well proven, and matured technology, with 25 years warranties on
solar panels. PV is the direct conversion of solar radiation (sunlight) into direct electric current by semiconductors
that exhibit PV effect. The PV can be applied to large scale power plants called photovoltaic power station or solar
parks. A solar park is connected to the grid, and thus supplies its bulk produced EP to this grid. Transfer solar
energy directly to EP is achieved without using moving parts means very low maintenance and operation
requirements. Once a solar park is installed (with relatively high cost compared to conventional power plat such as
combined cycle), the operating costs with no fuel supply are extremely low compared to conventional power plants.
This paper presents the technology and economics of the PV power station. It outlines the main
components of the PV power plants including the solar PV modules, module mounting and tracking systems,
inverters (or converters), and step-up transformers. It reviews the materials of the PV cells, the PV cells degradation,
and the existing PV power plant. Utility PV power plants around the world were reviewed.
PV panel are extensively used for small-distributed power generation used in homes and in remote areas.
One of the advantages of building solar parks in Qatar (and other GCC) is the coincide of its power output with the
high air conditioning electric power demand in hot summer days. The GCC is the Gulf Co-operation countries
including Saudi Arabia, United Arab Emirates, Qatar, Oman, and Bahrain. Recent reductions in photovoltaic cells
cost are the driving force behind the trend of building more solar parks worldwide.

Desalination and Water Treatment, 2014

Seawater reverse osmosis (SWRO) is the most cost-effective, practical, and widely used desalting... more Seawater reverse osmosis (SWRO) is the most cost-effective, practical, and widely used
desalting system. Its energy consumption, for Arabian Gulf seawater conditions is in the
range of 5–6 kWh/m3. These are less than 1/3 of the equivalent mechanical energy of the
thermal desalination systems presently used in Qatar. Besides, these thermal systems consume
2–4 kWh/m3 for pumping. Therefore, using SWRO system in Qatar can save up to
75% of the desalination energy cost. For Qatar, current desalting water production using
thermal methods is 480 Mm3/year at $0.1–1.2/kWh energy price; the energy cost is at least
one Billion US dollars per annum. A SWRO pilot plant is to be built in Qatar prior to building
a full size desalting plant (DP) in order to determine site-specific treatment guidelines
and to provide a full range of performance information to be used in the design of a full scale plant. The pilot plant will be tested when the feed water quality is good, and when
there are major storm events or algae blooms exist. Red tide events in 2008–2009 forced
many DPs in Gulf Co-operation Countries area to shut down. This paper reviews the SWRO
pretreatment process, which depends on local conditions and is the main factor affecting
the SWRO reliability. These include the extensively used conventional pretreatment of coagulation–
flocculation and granular media filtration (GMF). This is almost necessary for open
sea intake. Sever red tide blooms, when occur, cause clogging of GMF, resulted in biological
and organic foulants on SWRO membranes, and even DP shut down. So, low-pressure
membranes such as ultrafiltration (UF) or microfiltration (MF) can replace or integrated with
GMF. Since flotation is more robust than sedimentation (used in GMF) in dealing with high
concentration of suspended matter, dissolved air flotation is started to be used as pretreatment.
Since it is a new method that met success in several plants, it thoroughly reviewed in
this paper when integrated with GMF or membrane treatment. Additionally, the expensive
pretreatment with UF and MF is discussed with given examples. Preliminary experimentation
with SWRO pretreatment in Qatar was presented. Moreover, energy recovery devices
to be used with the pilot SWRO are discussed. Membranes configuration and the equipment
to be included are also outlined.

Desalination, 2015

The aim of the present work is to evaluate the effect of tube bundle arrangement and the seawater... more The aim of the present work is to evaluate the effect of tube bundle arrangement and the seawater feed distribution
on the dry zone and scale formation in the large sized Multiple Effect Distillation (MED) evaporator.
A mathematical model of the seawater feed distribution is developed and validated for a triangular pitch tube
bundle of MED evaporator. The developed model includes CaCO3 scale formation and CO2 release. The simulation
results showed that the dripping seawater flow rate on the column based on the 2nd row is lower than that of the
1st row. Consequently, the wetting rate of the tubes in the column based on the 2nd row is less than that based on
the 1st row. This explains why the tubes based on the 2nd row experience more CaCO3 scale deposit than that
based on the 1st row.
The simulation results showed that increasing the feed seawater to twice that of the original flow will reduce the
scale thickness by 15%. Increasing the tube pitch by twice the diameter will reduce the scale thickness by 30%. The
combined effect of modified feed flow and increase in the tube pitch would significantly reduce the scale precipitation
thickness.

Desalination and Water Treatment, 2014

International Journal of Energy Research, 2009

The effect of elevated inlet air temperature and relative humidity on a gas turbine (GT) cogenera... more The effect of elevated inlet air temperature and relative humidity on a gas turbine (GT) cogeneration system performance was investigated. The analysis was carried out on a GT of a capacity 171 MW at ISO condition, which is integrated with a dual pressure heat recovery steam generator (HRSG), the cogeneration system had been tested under Kuwait summer climate conditions.A computational model was developed and solved using engineering equation solver professional package to investigate the performance of a dual pressure GT-HRSG system. The suggested HRSG is capable of producing high-pressure superheated steam at 150 bar and 510°C to operate a power generation steam turbine cycle, and a medium pressure saturated steam at 15 bar to run a thermal vapor compression (TVC) desalination system. In this research, the influence of elevated inlet air temperature and relative humidity on the energy assessment of the suggested cogeneration system was thoroughly investigated.Results indicated that operating GT under elevated values of inlet air temperatures is characterized by low values of net power and thermal efficiency. At elevated inlet air temperatures, increasing relative humidity has a small positive impact on GT cycle net power and thermal efficiency. Integrating the GT with HRSG to generate steam for power generation and process heat tends to increase energy utilization factor of the system at elevated inlet air temperatures. Increasing inlet air temperature plays a negative impact on power to heat ratio (PHR), while relative humidity has no effect on PHR. Copyright © 2009 John Wiley & Sons, Ltd.

Desalination and Water Treatment, 2016

Qatar Foundation Annual Research Forum Proceedings, 2012

International Journal of Exergy, 2010

Desalination and Water Treatment, 2015

Desalination and Water Treatment, 2014

Desalination, 2015

Desalination and Water Treatment, 2014

International Journal of Energy Research, 2009