H2Tech - Q3 2021 - 25

HYDROGEN INFRASTRUCTURE DEVELOPMENT
and jetties are not included, as it is assumed that the existing
infrastructure in both Qatar and the UK will be used. However,
due to the requirement for the LNG value chain to have two
types of ships-LNG carriers and CO2
berthing CO2
ships-CAPEX for
ships was included in both Qatar and the UK.
The system boundary for each option is detailed in the folbeing
lowing
sections. A simple heat and material balance is developed
for each option, resulting in the same quantity of H2
delivered into the UK grid. Depending on the various losses of
product through the value chain, each option requires a different
quantity of natural gas feed.
The study is essentially based on 500 metric tons per day
capacity. The resulting individual unit pro(metric
tpd) of H2
cesses are sized based on the best information available for realistic
or available equipment. This methodology also applies to
typical ship sizes for the different products. LH2
value chains do
not exist at present, so all unit sizes were selected on the most
realistic size with accompanying CAPEX data. Included are optimistic,
scaled-up unit sizes and optimistic energy reduction
targets cited in the literature, so a sensitivity case is included to
capture potential savings as the LH2
The same H2
value chain is developed.
production configuration was used for all
options, and any additional heat integration opportunities in
the processes are not considered. For example, " cold " recovery
from LNG and LH2
heat recovery from the NH3
Operating days per year is assumed to be 350 days, and turnregasification
is not explored, nor is
and MCH processes. Therefore,
good energy savings may be found in the further development
of these processes.
Shipping fuel requirements proved particularly difficult to
establish. It was assumed that the LNG, CO2
ships could run on LNG, and the LH2
, NH3 and MCH
ship would run on LH2
boil-off gas (BOG). It seems likely that ships can be fueled by
NH3
tently between the different options.
The Qatargas 2 project9
in the future, but for this study it was decided to keep the
, where BOG reliquefication on the ship is unlikely to be
usage was carried out, using a simplistic method, consisLNG
value chain capacity includes
fuel consistent between the options with the exception of the
LH2
economic. Converting ship power requirements into LNG/
LH2
2 × 7.8-MMtpy LNG mega-trains (APCI AP-X), 5 × 145,000m3
LNG
storage tanks, LPG, additional condensate berths, sulLNG
tanks in the UK and regas facilities with a colEqs.
5-7 are used to determine the storage tank volumes and
number of tanks. A margin for the delayed arrival of a ship is
considered.
Frequency (days) = Operating days / Total round trip (5)
Working volume (m3
) = Carrier size (m3
)
frequency or 7 days × Rundown rate (m3
) + Minimum
÷ day)
Number of storage tanks = Working volume (m3
Tank capacity (m3
fur facilities, a fleet of 14 Q-Flex and Q-Max ships in Qatar, 3 ×
220,000 m3
lective capacity of 15.6 MMtpy. CAPEX and OPEX are costed
on a factor of (0.54 ÷ 15.6) for the entire value chain, excluding
the byproducts and additional berths. Only one Q-Max ship
was considered in the CAPEX.
Storage, loading, unloading and transportation costs are a
significant proportion of the overall value chain. The ship size
selected for each option is based on typical sizes cited in literature
and referenced later; however, this may not give the most
optimum or economic solution, as some options have lower
ship utilization than others, which is a key parameter for optimization
in any future study.
Selecting the ship size and speed defines the voyage duration
and number of trips and, therefore, the number of ships
required. It also defines the minimum onshore storage capacity
required. For the sake of simplicity, the same capacity was
assumed in Qatar and the UK. A minimum margin of 7 days of
) ÷
(7)
Cost estimation. The value chain for each option is defined,
and CAPEX and OPEX were calculated for each unit within
the process. For each part of the value chain, it is assumed that
there are 350 operational days/yr, and the overall lifetime is
30 yr. Data gathered for each unit are scaled up or down, as required
for the required unit size, using the standard estimation
factor to a power. A geographical estimating factor of 0.9 for
Qatar to 1 for the UK was also applied where necessary. Currency
conversion factors of pounds sterling (GBP) to U.S. dollars
(USD) of 1.32, and euros to USD of 1.14 are used where
necessary. Feed and utility costs for each location are detailed
in TABLE 1.
The approach taken in this study to determine the capital
cost of a plant, is calculated based on the scaling factor and corresponding
reference capital cost and capacity as outlined in Eq. 8:
Capital investment (S) = Capital investmentref
(S0
[Capacity (C) / (Capacityref
(C0
)]n
) ×
(8)
H2Tech | Q3 2021 25
(6)
around time in port (which consist of loading and unloading
hours) is assumed to be 3 days. Therefore, the number of ships
can be calculated as shown in Eq. 4:
Total number of ships = Total number of trips /
Number of trips per yr
(4)
Number of days per trip = [Distance (km / Ship) ×
speed (km / hr)]÷ 24
Number of trips per yr = Operating days in yr /
Number of days per trip + turnaround days
(2)
(3)
SPECIAL FOCUS
storage is included to allow for shipping delays, such as weather
or ship outages.
To determine the number of ships, it is important to identify
the number of trips required to transfer the total product from
the export terminal to the import terminal. The total number
of trips to transport a certain amount of product is calculated
using the carrier capacity shown in Eq. 1:
Total number of trips = Transported capacity (metric t ÷
yr) ÷ Ship capacity (metric t)
(1)
The maximum number of trips each ship can make per year
must then be determined. This is achieved by calculating the
number of days per trip, which depends on the carrier sea speed,
calculated as shown in Eqs. 2 and 3:
H2Tech - Q3 2021

Table of Contents for the Digital Edition of H2Tech - Q3 2021
