A new approach to the transport of plastic granules + Appendices

A new approach to the transport of plastic

granules

Yuri Henderikse 06 March 2001 Delft

-

A

Preface

This report is written for my final thesis project at the Technical University of Delft, department of Marine Technology, ship design at the chair of Prof. Ir, A. Aalbers.

The last 12 months I've been investigating possibilities of finding a new way to transport granule resins. The initiators of this idea are Tim Valentijn and Fritz Gartner of HO! Chemicals (Houston).

II Particularly' want to thank Gert-Jan Vossnack (Holvrieka, Sneek) and Bob Derks (Wagenborg Shipping By., DelfzijI) for their assistance in the design of a new transportation concept.

I also would like to thank Prof. Ir. A.Aalbers for getting me in touch with the various people and keeping me on the right track.

A lot of people and companies directly or indirectly contributed to the results of this report. Herewith I would like to thank them for their support.

Yuri Henderikse March 2001

Summary

This reports describes a new approach to the transport of plastic granules between the United States and South America. The main objective is to decrease the overall cost of the total supply chain of granule plastics with emphasis on the sea freight.

It is therefore necessary to find a sea transport concept that has lower costs per Metric Ton of granule resin than the current container freight.

Availability of cargo, Economical feasibility, Technical feasibility and Flexibility are factors that must be optimised.

There is an amount of approximately 122,000 Metric Ton (MT) each year is available to be transported from Houston to three of the Main ports in South America.

Cargo for a return trip is available but low freight rates are common on this trip due to the negative trading balance between South American and the United States.

During the first part of this project the following concepts have been generated and evaluated:

Containers Decktanks Cylinder tanker

Dedicated dry bulk ship with box-shaped holds

The container concept, which is widely applied, appears to be _{a relative expensive} way of shipping of bulk commodities like granule resin. Freight rates from port terminal to port terminal vary between US$70-135 per MT of granule resin.

Decktanks seem to be the optimal solution for ships having problems to make a

round trip going due to the specialized cargo of their shipments. This concepts has however insufficient capacity to be deployed on the trade of granular resins.

The cylinder tanker is original developed as a vessel that transports liquids. In this report a combination of chemical and non-chemical liquids as well as dry bulk vessel is investigated. Cylinder tanks that are transporting dry bulk need to be outfitted with a hopper to assure a free flow of the material. When the cylinder tanker is not

outfitted for the transport of chemical cargo but just non-chemical liquid _{a relative} cheap vessel is required due to the severe IMO regulations regarding chemical liquids concerning for instance the damage stability criteria and safety equipment needed. A combination of liquid bulk with granule resins gives problems with the different pumping devices that need to be used.

The bulk carrier with box shaped holds is currently used to ship various bulk commodities. The transport of granule resins demands severe requirements regarding the prevention of contamination and conveying.

It _{is inevitable to use coated ore non-corrosive materials as walls of the hold.}

Materials like aluminum and stainless steel are applicable. Normal steel needs to be painted; contamination with paint or rust is out of the question.

It is possible to use a big plastic liner to separate the cargo from the tank walls. The use of large plastic liners appears to be the most economical and flexible solution. This concept is called "Mega Big Bags"

Stability problems occur when a standard multipurpose vessel is outfitted with cylinder tanks. This results in a low amount of cargo that can be transported and therefore results in a high "required freight rate" (RFR).

The use of Mega Big Bags in the hold gives better results regarding the capacity and the RFR.

To improve the qualities of the cylinder tanker a conversion of the standard ship is analyzed. A widening of 2.5 meters results in much better stability qualities, which imply higher capacities and a lower RFR.

An increase in depth and beam of the standard vessel results in a relative "High Cube" ship. This high cube ship has excellent qualities when "Mega Big Bags" are used. This is due to the high volume to DWT factor of the vessel.

The RFR of the cylinder tanker vessel is much higher than the "Mega Big Bag" concept. The investment made for the cylinders is approximately five times as high as needed for the equipment used when exploiting the "Mega Big Bags". This enormous investment decreases the flexibility of the cylinder tanker concept.

An optimisation of the block coefficient and draught results in higher profits during a round trip.

There are several things that change the supply chain when the "Mega Big Bag" concept is used for the sea transport part of the supply chain. In the new situation the granule resin is transported in bulk to the Houston port where it is directly loaded into a bulk vessel. Where in the current concepts the containers are filled in the port of departure.

The pumping device that is needed is installed at every port that is called and consists of a pneumatic conveying device that can fill containers and is able to discharge the ship within a day, an installation aboard the ship is also possible.

The granule resin is transported in bulk to South America where it is discharged and put in containers immediately. The containers are distributed by truck to the various consumers, like in the current situation.

The large amount of cargo that arrive in the South American ports need to be stored before distributed, these cost are taken into account.

The decrease in sea transport costs can be as high as 40% where the effects on the decrease of the costs of the total supply chain are ample 18%, which implies an annual saving of 3.4 million.

Contents

1 Introduction

1

1.1 Approach 1

1.2 Involved parties: ₂

2 Background of granular plastics ₃

2.1 Introduction ₃

2.2 Polyethylene ₃

2.3 Polypropylene ₅

2.4 Logistics 5

2.5 Conveying of granular plastics ₆

Pneumatic conveying ₆

Negative pressure ₆

Positive pressure ₇

Mobile pneumatic conveying systems

Screw conveying ₈

Belt conveying

Conveying with the use of water 8

Conclusion of conveying devices 9

3 Trades between the U.S. and South America 10

3.1 Introduction ₁₀

3.2 Chemical trade _TO

3.3 Non-chemical liquid Bulk trade 11

3.4 Breakbulk trade 11

3.5 Dry bulk trade ₁₁

Coffee and cocoa beans ₁₂

Granule resins ₁₂

3.6 _{Trade of granule resin from The United States to South America 12}

Introduction ₁₂

Calculation of roundtrip ₁₃

Conclusion ₁₄

4 Outline of the current supply chain ₁₅

4.1 Three parts of the supply chain ₁₅

4.2 Four concepts ₁₆ 4.3 Cost specification ₁₆ Part I ₁₇ Part II ₁₇ Part III ₁₇ Total costs ₁₇ 4.4 Conclusion ₁₇ 5 Concept exploration ₁₈ 5.1 Introduction ₁₈ 5.2 Boundary conditions ₁₈ 5.3 Development of concepts ₁₈ Containers ₁₈ . . . ... -. .... . ... ...

Dry bulkship with batched box-shaped cargo holds 22

5.4 Amount of cargo to be transported 24

8 Evaluation of the concepts .,. .26

6.1 Criteria .... 5 T o. 26

6.2 Concepts ,

-

-

. , , 26

Cylinder carrier r ... s ..p ... .. , 26

Dedicated dry bulk carrier with box-shaped holds ₂₈

6.3 Conclusion ₂₉

7 Intermezzo: economical evaluation model/ 4 30

7.1 Introduction ,.

. .

-

30

7.2 Test case i, ₃₀

7.3 Calculation of charter rate and RFR ₃₃

8 Application of M-borg vessel ₃₄

i

8.1 Introduction ₃₄

1 8.2 Markborg with cylinder tanks

1 i 35

, 8.3 Markborg with plastic liner.

- -

₃₇

Load- and discharge procedure of 'Mega big bags' ... 4 9 4 40

llConclusion.

41 9 Conversion of M-Borg, a ..,.., N... .... .. 42 9.1 Introduction _f .111 '4 I , .,,,- ..., ... ....

.

42 II 9.2 Widening of M-borg ₄₄ I Standard 'M-Borg el 9, ... -

.

44 I I _{Widened M-Borg 45} ,

9.3 Optimising the widened ship ₄₇

Fuel and charter costs during a round trip Port costs

9.4 Results of converted M-borg _{..,_ . r .. 54}

Widened M-borg with containers , 54

Widened M-borg with cylinder tanks . ₅₄

Widened M-borg with bulk cargo._ I

.

.. 4( i 4. 57

9.5 Results of "Triangle trip"

.

..., A _58,

Freight rates on triangle trip . 60

9.6 Comparing the results ₆₁

Roundtrip with 15-year depreciation period

-. 61

Roundtrip with 5-year depreciation period ,

-

₆₁

"Triangle" trip with 5-year depreciation period

_.

.1 Sir 62

9.7 Conclusion

_.

₆₂

10 Effects on supply chain

-

₆₄

10.1 Triangle trip ₆₄

10.2 Pound trip

.

I 65

Costs due to loss of interest ₆₆

Part I

_.

_{, , '66} Part II _.---...

.

,

Part III -, .

.

- - ,... .4 66 10.3 Concept comparison 4+1 4 66 10.4 Conclusion - .!...N. ,.., el ,., 67 11 Conclusions _

-

. _{, 68}

Trade of granule. resin

-

_{.. 68}

Standard M-borg can not compete with container transport _{, . 68}

Widening and increase of depth decrease overall transport costs ₆₈

Cylinder tanker transport costs too high ₆₈

"Mega Big Bag" concept transport cost lower than container freight rates ₆₉

Effects on the total supply chain _{. 69}

12 Recommendations ₇₀

13 References ₇₁

14 Appendices _{. 73}

14.1 List of contacted people

-49

51

14.2 Pneumatic conveying properties 73

14.3 Outline of supply chain 73

14.4 Resistance calculation by method "Holtrop and Mennen" 73

14.5 Ship mass calculation by method "Westers" 73

14.6 New-building price calculation by "Evaluation design sheet" 73

14.7 Cylinder tank properties ₇₃

14.8 Charter rate calculation 73

14.9 Cost specification of cylinder tanker concept 73

14.10 Cost specification of Mega big bag concept 73

List of figures

figure 11 Molecule structure 'of PE yo. 3

figure 2 Molecule structure of PP 5

figure 3 Negative pressure pneumatic conveying system' . 6;

figure 4 Positive pressure conveying system ₇

figure 5 Vigan rotary air lock 7

figure 6 roundtrip 14

figure 7 Supply chain ₁₆

figure 8 Chemical cylinder tanker 17 4 20

figure 9 Double pumping system in hopper tank , -; ; 21

figure 10 Dedicated self-unloading sugar carrier , 23

figure 11 Cross section of self-unloading dry bulk carrier, . 23

figure 12 range of cargo ₂₅

figure 13 Cylinder calculations ₂₇

figure 14 mobile pneumatic conveying system 'Vigor,' 100 '(type diesel) 28

figure 15 M-borg type vessel: Markborg ₃₄

figure 16 holds of "Markborg" outfitted with cylinder tanks ₃₆ figure 17 Markborg with all available grain bulkheads positions occupied. ₃₈

figure 18 sketch of "Mega Big-bag" ₃₈

figure 19 Loading and discharging of a 'mega big bag' ₄₀

figure 20 Suction, nozzle ₄₁

figure 21 Design spiral' ₄₃

figure 22 widened M-borg ₄₄

figure 23 Power chart of standard M-borg ₄₄

figure 24 Power chart of widened M-borg , ._ 45

figure 25 Widened M-borg with increased depth ₄₆

figure 26 Power chart of widened M-borg with adjusted Cb A 46

figure 27 Determination of cargo capacity ₄₇

figure 28 Calculation hold volume. ₄₈

figure 29 Fuel and charter costs versus ship's speed ₅₀

figure 30 Fuel and charter cost versus ship's speed at HFO price of US$200/MT 51

figure 31 Pumping and port related costs ₅₂

114

figure 32 Total costs _{. 53}

figure 33 Holvrieka stainless steel tank

figure 34 Widened M-borg with cylinder tanks _ ₅₆

figure 35 Cost of Mega Big, bags ₅₈

figure 36 "triangle" trip ₅₉

figure 37 Pneumatic conveying' unit ₆₀

List of tables

table 1 decision criteria of conveying device 9

table 2 Chemicals that are transported from Latin America to the gulf 10

table 3 Chemicals that are transported from the gulf to Latin America 11

table 4 Dry bulk commodities that are transported from Latin America to the gulf 12 table 5 export of PE and PP granulates from Houston (1999) by a chemical company 13

table 6 comparison of transport chain costs 16

table 7 Containers 19

table 8 Decktanks ₂₀

table 9 Two variations of the decktanks 20

table 10 Cylinder tanker 22

table 11 various concepts of cylinder carrier 22

table 12 Dedicated dry bulk ship 24

table 13 various dry bulk ship 24

table 14 Decision criteria of concepts 29

table 15 general particulars "Markborg" 35

table 16 double bottom ballast tanks filled 36

table 17 double bottom- and wing ballast tanks filled 37

table 18 Costs of cylinder concept 37

table 19 cargo holds filled with granule resin 39

table 20 Cost of bulk carrier with liner 39

table 21 Main particulars ₄₇

table 22 Hold capacity ₄₇

table 23 light ship weight calculation 49

table 24 Particulars of design variations ₄₉

table 25 particulars of converted vessels ₅₄

table 26 widened m-borg with maximum amount of 20ft; 14MT containers 54 table 27 widened m-borg with cylinder tanks and double bottom tanks filled 56

table 28 Particulars of widened cylinder tanker 57

table 29 costs of widened and increased depth liner- carrier 57

table 30 Cost and revenues of widened and increased depth M-borg with liner 57 table 31 Costs and revenues of plastic lined vessel in "triangle" trip 60

table 32 Roundtrip with 15-year depreciation period 61

table 33 Roundtrip with 5-year depreciation period 62

table 34 "Triangle" trip with 5-year depreciation period ₆₂

table 35 Costs of supply chain in triangle trip 64

table 36 Costs of supply chain in round trip ₆₅

table 37 progress of transport ₆₆

. .., .

.

.S.,.

.

Chapter 1 _{Introduction'}

Introduction

The idea of transporting high value commodities in bulk is proposed by Holland Chemical International (HCI). HCI is a company that mainly transports chemicals but there is a department that transports plastics as well. The question rose whether it would be possible to transport high value dry bulk commodities like granular plastic in bulk, the same way as chemicals are transported.

Currently the freight costs of the transport of polyethylene/propylene granule resins between the US Gulf and Latin America countries are relative high.

These products are transported in 3 ways:

The first method is in containers; the granulate is put in bags of 25kg, those bags are put on pallets and the pallets are transported in containers on ships.

The second way is by seabulk-containers, the granular pellets are put as bulk in a container.

The third way is in big bags of approximately one ton that are lifted aboard the ship or put in containers.

The transport process requires innovation and optimisation

This project is about an innovative concept that will be generated to transport granular bulk as economical as possible. The option of combining this transport with the transport of liquid bulk chemicals will also be considered.

1.1 Approach

This reports describes a new approach to the transport of plastic granules between the United States and South America. The main objective is to decrease the overall cost of the total supply chain of granule plastics with emphasis on the sea freight.

In chapter 2 a description is given of the product granule resin, what is possible with this product and what route does this product follow from producer to consumer.

To find a new way of transporting plastic granulate an investigation is necessary what other commodities are transported on the existing trade route. These transports of cargo are useful when a return trip of a certain concept needs to be filled. It is always possible to sail back empty but the _{presence of cargo in the hold} increases the revenues for the total trip. So the trade routes that _{go between} Houston and the South American countries and vice versa is mapped in chapter 3. The current supply chain of granular plastics is discussed in chapter 4 and four possible concepts for the sea transport of granulates are evaluated in chapter 5. An evaluation of two of these concepts is outlined in chapter 6. An application of two of the concepts with a standard multi purpose vessel is given in chapter 8 and this vessel is further applied and converted in chapter 9. In chapter 10 the effects of the

Chapter i _Introduction

1.2 involved parties:"

To execute these tasks, there has to 'be access to a large amount of information. Evaluating on which trading routes the cargo is transported and what the transport fees are, the support of a shipper or ship owner is desired.

For the possibilities of designing and building a ship the advise of a shipyard is needed and to get grip on what tanks can be installed a tank building company should be advised. A ship owner has to decide whether the ship will be build. The following parties are considered,:

Producer :American parties

Shipper :HCI Chemicals

Ship owner :Wagenborg Shipping Sty.

Yard :To be named

Chapter 2 Background of granular plastics

2

Background of granular plastics

The background of granular plastic is outlined in this chapter. Also a rough introduction is given in the logistics of this material. The various ways of conveying granular materials is discussed in paragraph 2.5.

2.1

Introduction

Plastic granulate is a material that is widely ranged and has applications all over the world. Polyethylene is the largest-volume plastic used in the United States. One of the reasons for its wide usage is the existence of many different grades, with a wide range of properties.

The most common used polymers of the vast

array of plastics available is

enumerated below: ABS Butadiene

Polycarbonate (PC) Polyethylene (PE)

Polymethyl methacrylate (PMMA) Polypropylene (PP)

Polystyrene (PS)

Polytetrafluoroethylene (PTFE better known as Teflon)

Each type of polymer is manufactured in various grades with different average

molecular weights, different molecular weight distribution, different additives and different manufacturing processes, all of which affect the properties. In the following paragraphs a brief introduction will be outlined to the various classes of polymers.

2.2 Polyethylene

Polyethylene (PE) is prepared by direct polymerisation (Miller) of ethylene (C2H2) in the presence of an appropriate catalyst:

01110

Ana

figure 1 Molecule structure of PE

Although the simple formula suggests that all the PE molecules should be linear, under actual polymerisation conditions some side chains are formed. The two factors

Chapter 2 Background of granular plastics

chains existing on the mainly linear molecules. Grades with molecular weights larger than 200,000 are generally considered as the high-performance grades. The high molecular weight show improved toughness, improved tensile strength, a higher softening and other mechanical properties related to the strength. Ductility and resistance to stress corrosion cracking tends to decrease with increasing molecular weight. The longer chain length and the increased molecular attractive forces increase viscosity in the liquid state and decrease the processibility of the grade. The molecular weight and the number of side chains, which exists on the mainly

linear polyethylene, depend on the techniques employed during the polymerisation

process.

There are to ways of polymerisation of PE, the high-pressure and the low-pressure method.

The high-pressure method results in many side chains and low molecular weight resulting in the production of low density PE (LDPE). Typically side-chains are 1 to

65 carbon atoms long and about 3% of the carbon atoms in the main chain may contain these side chains, with most side chain 1-6 carbon atoms long.

The low-pressure polymerisation method utilizes catalysts which tend to produce

more linear PE molecules, resulting in grades of higher densities and higher

crystallinity.

The grading based on molecular weight, density and number of side-chains separates PE into the following types:

UHDPE: UltraHigh-Density PolyEthylene

HDPE: High-Density PolyEthylene

LLDPE: Linear Low-Density PolyEthylene

LDPE: Low-Density PolyEthylene

Polyethylene is copolymerised with many other polymers. Copolymerisation with Polypropylene increases the strength and the impact resistance. Copolymerisation with ethylene vinyl acetate (EVA) produces a wide range of properties dependingon

the vinyl acetate added (VA). Blends of LDPE and LLDPE combine the processing ease of LOPE and the improved mechanical properties and the resistance to stress

cracking of LLDPE.

Desirable properties of PE are: Low cost

Good toughness \ Near-zew moisture absorption Excellent chemical resistance

Excellent electrical resistance Low coefficient of friction Good moisture barrier

Good corrosion cracking resistance Highest impact strength of any polymer

Good abrasion resistance-used for bulk handling equipment

Typical' uses of PE are: Piping

Automobile interior parts Containers

Cable insulation

Film and bagging material Material handling equipment Wear-resistant flat bearing

Chapter 2 Background of granular plastics

2.3 Polypropylene

Polypropylene is the other major plastic that is used in the United States. The formula of PP is:

H H

I I

H

CH3

figure 2 Molecule structure of PP

The relative tight small CH3 group provide sufficient steric hindrance that good molecular alignment can occur. As a result, PP is highly crystalline, approaching 90% crystallinity [FEW Although PP is mainly isotactic (as it must be to be crystalline),

about 5% of the atactic form is present in the commercially available materials. The fraction of the atactic form varies between manufacturers, producing different mechanical properties. As with most crystalline polymers, increasing the rate of cooling during solidification reduces the crystallite size and improves the toughness of the product.

An unusual characteristic of PP is that very high molecular weights lead to poorer properties.

The fatigue characteristics of PP are excellent and it is extensively used for solid hinges. It has excellent moldability and has less shrinkage on soldification than PE.

Desirable properties of PP are: Can be sterilized

Excellent fatigue resistance Excellent moldabillity

Typical uses of PP are: Hinges

Computer cabinets Piping

Impellers

2.4 Logistics

PE and PP are produced in granulates or in powder form. Granulates is the major method used by producing plastics. The granulate is made by chemical companies and then transported to companies that produce plastic materials like foils, bags or

complete car interiors. Granulate plastic is put in a resin extruding machine and extruded into a mould.

At the chemical plant the granule material is put into containers and transported to the port where the containers are put in container vessels and transported to overseas costumers. Currently there is a big need of granular plastics in South American countries while there is no plant that produces granular plastics. Therefore the North American plants provide the South American countries with granular plastics. The chemical plants are located nearby Houston and the consumers are located in several South American countries (see chapter 01. The transport from the South American ports to the in-land consumers is carried out by truck.

Sometimes rail hopper cars are used to transport granular material from the plant to the port, where it is put into containers.

Chapter .2 'Background of granular plastics

Z.5 Conveying of granular plastics

To load and' discharge cargo from' a bold or tank in a ship' a conveying, system has to be chosen,. The common way of handling bulk commodities is by pneumatic:, screw-or belt conveying, pumps as well as by cranes.

Conventional granulate onshore tanks are discharged at the bottom of the tank by gravity; in a ship this is a very complicated way of discharging cargo. The discharge point is just above the tanktop of the ship. The tanks have to be installed higher in the ship to assure enough clearance underneath the tank for pumping equipment..

This results 'in a

higher ship with a

higher GT and problems with _stability

requirements.

Tanks in chemical carrier are equipped with dedicated deepwell pumps that pump the cargo from' the bottom of (the tank through a pipe upwards and discharge at the top of the tank.

The various methods all have advantages and disadvantages. In the following paragraphs, the different conveying methods will be discussed'.

Pneumatic conveying

Pneumatic conveying is most often used when large amounts of small, pellet size. cargo need to be discharged from a cargo hold. It is a relative simple and low cost

solution.

There are 2 ways of pneumatic discharging; by suction (negative pressure) and by blowing (positive pressure).

Negative pressure

When a tank or hold is discharged from top with a pneumatic conveying system a negative pressure system is used. The material is sucked into a hose or pipe and is. discharged at the, top of the tank (see figure 3),.

°IOW

am mow a a a a iss max OM=

AM MI WINI IMP EMI JIM =II

MN MO OM MI6 SIM II=

ME SIM AIM II= IS NI NM NM OM =MI 20

/

t

figure 3 Negative pressure pneumatic conveying system

'Discharge rates of 60-100 MT/h are feasible with a mobile installation. Discharge. rates of 200-500MT/h are possible with a fixed 'installation at the pier.

the pump. in a' positive pressure system the pump needs to be placed underneath the 'tank, which raises the position of the tank in the ship.

Positive pressure

Positive pressure systems can obtain a discharge rate of about 125MT/h per tank. At the bottom of the hopper of the tank, a feeder (rotary airlock (see figure 4 and figure 5) is used. The position of the feeder, is adverse for the center of gravity (VCG) of the cargo.

IL

figure 4 Positive pressure conveying system

This device seals off the high-pressure system from the, cargo and feeds the cargo discharge pipe with granulates. When the granules resins are in the positive-pressure system it is transported upwards in the ship and, this pipe leaves the ship when it reaches above the weather deck. The VCG of the ship will rise and, therefore the stability requirements are more difficult to be satisfied.

I

figure 5,Vigan, rotary air lock

Mobile pneumatic conveying systems

Mobile conveying units are finding an increasing role in the bulk handling of grain and other granular materials. These units offer a reliable and flexible solution _{to the} question of barge and ship unloading' where it is impracticable and uneconomical to

MM.

a a a MIN MIN

IM on MIN

11=110 MOM NM _{WM EM}SIM =Mr

MIN MI NM NM MI MOP MS MINN MI

OM WPM =II NM

INN MI

1,1

Chapter 2 _{Background of granular plastics}

Chapter 2 Background of granular plastics

use conventional fixed equipments. The diesel engine driven units can be positioned anywhere aboard the ship or at the dockside. This makes this type of unit ideal where there is no existing fixed bulk handling equipment; the installation of fixed equipment is not economical, due to for example low tonnages to be handled, or where there are limitations on space or problems with load bearing areas.

Screw conveying

Instead of using air as a conveying method it is also possible to use a screw conveyer [Rademacher721, a large coil in a tube that rotates around its longitudinal axis and thereby transports the cargo. This method is, just like the air conveying method, possible on two ways, from the top or from the bottom of the tank. An advantage of the screw conveyer is the low abrasion that occurs during conveying compared to pneumatic conveying. A problem occurs when different kinds of cargo need to be conveyed in contrast to the pneumatic conveying unit, the screw conveyer is not self-cleaning.

Belt conveying

Coffee beans are currently conveyed by covered belt conveying systems. Belt conveying causes the lowest abrasion to the cargo and is therefore applicable at coffee beans.

When a belt conveying system is inserted in a hold it takes very much space because of the transportation belts that are guided through the hold. This system is also not self-cleaning. If coffee beans are transported the belt needs to be cleaned afterwards to prevent the contamination of coffee beans with for example plastic pellets. This method is also used in combination with pneumatic conveying. The commodity is sucked out of the hold and transported to the discharge point at the quay by a conveyor belt.

Conveying with the use of water

Another way of discharging the granule pellets is by liquidizing the pellets. Water is pumped in the tank; the pellets start to float when the water level reaches 95%. By pumping large amounts of water in the tank, the pellets start to flow outside through a pipe at the top of the tank.

This is the easiest way of discharging a tank; no extra pumps have to be installed when a standard chemical carrier ship is used to transport the granule resin. The slop water of the chemical tanks can be used (before contamination).

The only disadvantage of this method is that problems occur with the drying of the pellets. To dry the pellets an enormous drying installation (spin dryer) is needed, this installation has to be installed at any port of discharge. The capital and running costs of these operations are high.

This way of conveying is not applicable to commodities like coffee beans or cocoa, for obvious reasons.

Chapter 2 Background of granular plastics

Conclusion of conveying devices

To make a conclusion about which concept fits the best for the transport of

granulates a decision table is outlined in the table below. The decision criteria are: Costs

Reliability Contamination

Self-cleaning and contamination Flexibility

Technical feasibility

Costs

Mark Factor

table 1 decision criteria of conveyin6 device

The pneumatic conveying method seems to be the most optimal solution to convey granular material.

Pneumatic conveying will therefore be the method that is used in this project to convey plastic granules.

Reliability Factor

Mark

Contamination flexible

Mark Factor Mark Factor )Technical feasibility Mark Fcatir 7 5 5 Total Screw 3 8 6 6 4 7 136 Belt 7 3 8 4 7 4 5 136 Pneumatic 7 3 6 4 8 4 7 4 8 145 Water 8 3 8 4 8 4 6 4 I 3 5 127

Chapter 3 Trades between the U.S. and South America

3 Trades between the U.S. and South America

In this chapter the trades will be discussed form South America to the United States and vice versa. The amounts of cargo that are transported and the transport cost of the shipments are emphasized. All the freight rates are Free On Board (FOB) values. The transport of granule resin is outlined in paragraph 3.6

3.1 Introduction

To find a new way of transporting granule resins and other high value bulk commodities, the various trade routes have to be defined. A distinction is made between:

Chemical trade Dry bulk trade Liquid bulk trade Breakbulk trade

In this project the trade route between US Gulf and Latin America countries is evaluated.

3.2 Chemical trade

In the chemical bulk trade materials like glycerine, alcohol but also vegetable oils are transported. These commodities are most often shipped in dedicated chemical carriers outfitted with stainless steel box-shaped cargo tanks. The tanks are equipped with cooling and heating coils as well as washing equipment and a deepwell pump in each tank.

For the transport of methanol, specialized methanol carriers are available that can ship methanol-like products only.

Chemical carriers are relative expensive because of the well-equipped expensive stainless steel tanks and the severe requirements for these types of ships concerning the safety according to the International Maritime Organisation (IMO) and MARPOL regulations.

The following chemical commodities are transported on the trade route US Gulf, Latin America and the other way around [Drewry] and [Ferrer].

Latin America to Gulf

Commodity Pollution Category Value pi/M77 Amount (MT/year] Freight rate WM77

Methanol III _{150000 35-45}

Glycerine III 5000

MTBE D 55920

Propyleen glycol III ₂₅₀₀

Fats and oils D 300-650 4500 35-45

Palm oil D 600 4500 35-45 Vegetable Waxes D 4000 o ,o o o

Chapter 3 _{Trades between the U.S. and South America}

table 3 Chemicals that are transported from the gulf to Latin America

The pollution type is defined by the IMO published in the International Code for the construction and equipment of ships carrying dangerous chemicals in bulk (IBC Code). The pollution categories can be A, B, C and D. These categories are assigned to each product under Annex II of MARPOL 73/78. "III" means the product was evaluated and found out to fall outside the categories A, B, C or D.

Chemicals in the category A, B, C or D have to be transported in ships that comply with the IBC Code regulations and requirements. Cargos of category "Ill" do not. Many category "Ill" commodities are currently shipped in expensive chemical carriers while cheaper solutions are applicable.

It is therefore possible to combine these category "Ill" commodities with normal high value bulk cargo and with granule resins in the same ship.

3.3 Non-chemical liquid Bulk trade

The non-chemical liquid bulk trade practically consist of juice and edible oils, there is a large market of orange and apple juice transported from Brazil to the US and Europe, most often these commodities are transported by refrigerated juice-carriers. For example a general cargo ship from Gearbulk is equipped with refrigerated cylindrical tanks. The tanks are installed

in one of the cargo holds. The ship

transports juices from Brazil to the rest of the world. When the ship sails back from Europe, North America or the South East to Brazil, the tanks are empty.

No other commodities are transported in the tanks to prevent contamination. This condition makes the transport of orange juices relative expensive.

Edible oils are currently transported in chemical carriers. The cargo holds that are

used for the oils are also used for non-edible and toxic commodities. This is not the most ethical and efficient way.

There are also bulk shipments of edible alcohol containing products like wine.

3.4 Breakbulk trade

Breakbulk is bulk cargo that is shipped in general cargo ships. The cargo is put in bags or on pallets. The pallets are lifted aboard the ship. This is _{a labour intensive} way of loading and discharging a ship.

Meat, citrus fruit and bananas are the commodities that are predominantly shipped on the trade route Latin America US Gulf. They are most of the time shipped in refrigerated vessels, part of the times refrigerated containers are used.

3.5 Dry bulk trade

There are two different dry bulk trades. Large dry bulk transports like coal, _{ore and} grain and on the other hand more specialised dry bulk trades like sugar, coffee beans and granule resins. In the content of this project the smaller more specialised bulk trades will be discussed. The trade between the Latin America and US Gulf consists of the following commodities:

Gulf to Latin America Commodity Pollution Category Ethylen glycol

Cotton oil

Laurie alcohol Ill

Other glycols

Chapter 3 _{Trades between the U.S. and South America}

table 4 Dry bulk commodities that are transported from Latin America to the gulf

Coffee and cocoa beans

Almost all dry bulk commodities are shipped in bulk except from coffee and_cocoa beans. These beans are shipped in bags and put in containers or in bulk containers. Humidity is a problem with the shipment of this kind of cargo in containers. During a trip from the southern to the northern hemisphere the cargo cools down and the water in the air of the container starts to condensate.

Ventilated containers are a possible solution for this problem. These containers are rare and therefore expensive. It is also possible to ship the beans in large ventilated cargo holds or tanks in a bulk ship. Damaging the beans is a major point of concern. This could be in combination with granulates; coffee beans from the Latin America to the USA and granulates back from Houston to Latin America.

Granule resins

Granule resins are a dry bulk commodity that is shipped form US Gulf to Latin America. The value of granule resins is higher than the other dry bulk materials. A metric ton of polyethylene pellets has a value of about 1,000USS. Currently the polyethylene pellets are transported in 20 ft bulk containers containing approximately 17 MT. The stowage factor of the resin varies between 0.50-0.60 MT/cum. The shipment costs are US$ 105-135/MT from Houston to Latin America and US$ 85-105/MT from Houston to Central America.

3.6 Trade of granule resin from The United States to South America

In this paragraph a trade route is investigated on which the new concepts can be deployed. One of the chemical companies that produces granulates revealed their annual trade, the fact and figures are outlined in the following paragraphs.

Introduction

This chemical company is a large granule resins producer. The plant in Freeport (Texas) provides the need of granulates in the South American countries. Brazil, Argentina and Columbia are their main consumers.

The trade mainly consists of 10 different grades of PE and PP.

Currently these products are transported from the plant to the terminal in containers or in hopper cars'. A container ship transports the containers from Houston to the South American countries. Over there the containers are delivered to the_customers or discharged into silo tank cars that transport the resin to the end-user.

Large customers take 2,000-5,000MT each year, there are several smaller

costumers but 80% of the trade goes to the large customers.

' Hopper cars are railcars that can carry 100MT of granulates and can be loaded and discharged at the port as well as Latin America to Gulf

Commodity MO Type Value IS/M77 Freight rate [W77

Coffee/cocoa Sugar Flour/wheat Cement Dry bulk Dry bulk Dry bulk Dry bulk 500 200 150 35 90 22 25 25

Chapter 3 _{Trades between the U.S. and South America}

table 5 export of PE and PP granulates from Houston (1999) by a chemical company

A total of approximately 200,000MT of granulate is transported each year from Houston to Latin America.

To ship 200,000MT approx. 12,000 20ft containers are needed each year.

20 ft Containers are capable of transporting 17MT of granulate while 40ft containers can contain 25MT; 20ft's cube-out and 40ft's weight-out.

The containers that are mainly used for this way of shipping are open hatch containers. The container is outfitted with 3 or 4 hatches that are used to fill the container by gravity from silos.

When the container is transported to the customer it needs to be returned to the port terminal within several weeks, this is an agreement that is made between the shipper and the producer. The prices that are outlined in table 5 are freight rates based on the agreements made between the chemical company and the shipping company.

80% Of granulates that are transported to Brazil are discharged in Sao Paolo. The main areas in Argentina are Buenos Aires and Cordoba

There is also a trade between Houston and Europe. Currently there is a large need of granulates in Europe that cannot be fulfilled by the European producers.

Calculation of roundtrip

The number of ports that are called should be as low as possible to optimise the supply concept. So three main ports are chosen

When the countries that are large consumers are chosen, the following round trip can be generated.

This round trip is approximately 13,000 nM long.

80% Of the cargo consumed by a country is imported through the main port, as supposed.

Country MT/year Freight rate $/MT [20ft] Freight rate $/MT [40Jft] Brazil 80.000 105 95 Argentina 40,000 84 95 Columbia 30,000 130 102 Chili 18.000 80 Guatemala Puerto Rica Honduras 8.000 95 Uruguay Venezuela 6,000 130 15,000 8,000 6,000

Chapter 3 Trades between the U.S. and South America

So for Columbia 24,000MT of granulates is transported to Cartagena each year; for Brazil 64,000 a year to Sao Paolo; for Argentina 48,000 a year to Buenos Aires. When a

margin of 10% is taken due to the transport of

special grades or incompatibility with the consumer a total of approximately 122,000MT a year has to

be shipped. Houston 0--MT/Yiree Buenos Aires 48,000 ° mrnear figure 6 roundtrip

Conclusion

There is a large amount of granule resins that can be transported from Houston to several South American countries. Approximately 122,000MT can be transported to the three "Main ports"; Cartagena, Santos and Buenos Aires.

There are a lot of other products that go around between the United States and several South American countries. It is however know that there is a surplus of cargo that is shipped to the south. It will therefore be difficult to find a commodity for a return trip of a granule resin-transporting vessel.

The connection with the supplier and the consumer is left aside in this chapter. It is very important to look at the entire supply chain when a new sea transport concept

is designed.

64,000 MT/Year Sao Paolo

Chapter 4 _{Outline of the current supply chain}

4

Outline of the current supply chain

In this chapter the total supply chain will be discussed. It is very important to link the transport from the supplier (plant) to the sea transport and then distribute it to the consumers. If for instance the sea transport has much lower cost but the connection with the other two parts of the supply chain is very expensive due to extensive transhipment procedures a sub-optimal supply chain will be discussed. The following paragraphs will pay attention to the three parts of the current supply chain and the interaction between each other.

4.1 Three parts of the supply chain

The total supply chain is divided in three parts to get a clear view on the total costs. The supply chain consist in these three different parts:

Part 1 _{Transport from production plant to the seaport}

Part 2 Sea transport from North American port to South American port Part 3 Distribution from South American ports to consumers

Currently the part 1 of the chain is carried out on two ways:

Granulate

is bagged in bags of 25 kg, these bags are put in

containers and the containers are transported by truck to the port. More often granulate is put in rail hopper cars that contain 100MT and is transported to the port where it is bagged in bags of 25kg and put in 20ft containers or directly put in containers with a liner. The hopper cars are filled at the plant and stored at the marshalling yard. The train shipments with the rail hopper cars go in lots of approximately 3000MT (30 hopper cars). The thirty 100 MT hopper cars are transported by one railway engine.

A company at the port discharges the rail cars into containers. The containers are

stored approximately 500m from the container terminal. The containers are shipped in parcels of 50 containers with container ships. It takes about 3/4 of an hour to fill an entire 40ft container with 25MT of granulate.

A container vessel carries out part 2 of the chain. The container is put aboard in the Houston port and discharged in one of the South American ports.

The 25 kg bags are discharged into a flat bed truck and transported to the consumer when the container arrives at the port of destination or the lined container is directly transported to the consumer. There needs to be distribution point in both conditions. This represents part 3.

Some of the consumers prefer to have granulates in bulk. For these consumers bulk containers are filled with granulates and are transported from plant to consumer in a PE-lined container.

Currently a part of the granulate is bagged in North America, then put in containers and transported to the Southern hemisphere.

Chapter 4 Outline of the current supply chain

4.2 Four concepts

Four concepts are generated to compare the cost in the total supply chain. The concepts I and II are concepts that are currently used. Concepts Ill and IV are new concepts:

40ft Container filled at plant transported with truck loaded into container vessel distributed with truck

Rail hopper car filled at plant transported to port loaded into containers and then into 40ft container vessel distributed with truck

Rail hopper car filled at plant transported to port loaded into cylinder tanker vessel discharged into 40ftcontainer and distributed with truck

Rail hopper car filled _{at plant transported to port loaded into bulk vessel} discharged into 40ft container and distributed with truck.

The four concepts are visualized in figure 7. This visualization is also available in the appendix 14.3.

PART I PART II PART III

-I- 1 a , . w Ns, ' 0 _{_} u 3

figure 7 Supply chain

A cost specification of the four concepts is discussed in paragraph 4.3. The

influence of the loss of interest due to the number of days the cargo is on the way is outlined in paragraph 10.3.

4.3 Cost specification

The costs of the various parts in the four concepts are outlined in table 6:

4411121ZZEULF---C'

gLualt=1;pil,-

,

Action Concept I Concept II

Load unit at the plant 4.00 $ 3.00

Transport frOm plant to port 12.00 $ 9.00

0

_{Fill,container}

$ 9.00

S Storage $ 3.00 $ 3.00

t

Transport from storage to port $ 3.00

P Subtotal $ 19.00 $ 27.00

S a

Load+discharge _{$ 25.00 $} 25.00 r II Sea transport $ 70.00 $ 70.00

t

Subtotal $ 95.00 $ 95.00

$

Fill 'container Port to storage NI lit Storage $ 3.00 $ 3.00 Distribute container $ 40.00 _$ 40.00

T

_{Subtotal $ 43.00 $ 43.00} Total $ 157.00 $ 165.00 1. ' r$ $ /

Chapter 4 Outline of the current supply chain

Part I

The transport with rail hopper trucks is cheaper than the containerised transport. The production plant discharges the granule resin directly into the rail cars. The cars are stored on the marshalling yard and transported to the port with 30 rail tender cars at a time. Granular resin in concept 2 is bagged (US$ 5/MT) in the port then it is

transported to the port by container truck (US$ 16/MT).

Part II

There are fixed rates of container shipment and port handling costs in the concepts 1&2. The costs of shipping one MT of granulate from Houston to The South American ports varies from US$ 70 to US$ 135. This depends on which South American port is called and which arrangements have been made between the

shipper and the chemical company. Also the size of the container is of importance, for this comparison we look at the 40ft container average price of US$95/MT

Part Ill

The costs in the third part depend on the wishes of the customers and the size of the parcels. Large parcels are transported in bulk containers or sometimes in silo trucks. Small parcels are transported in bags and stacked on pallets in flat bed trucks. There needs to be a storage point in both of the concepts to distribute the

containers from. Distribution costs

of the container are equal to both of the

concepts. Practically these costs will vary depending on the location

of the

consumer.

Total costs

Currently the total costs of transporting one Metric Ton of granulate from the Houston plant to the South American consumers varies between US$157-165. Approximately 45% of these costs are ascribed to the sea transport and the loading and discharging of these ships.

4.4 Conclusion

When compared to other bulk freights the overall costs of the containerised sea transport are relative high. Therefore an optimisation of this part of the supply chain will be further discussed in the following chapters. Finally the consequences of the new sea transport concepts to the total supply chain will be evaluated in chapter 10.

chapters Concept exploration

5

Concept exploration

5.1 Introduction

A ship is usually the cheapest way to transport goods.

Currently the container market is _{booming, many goods are transported in}

containers. Formerly many goods were transported in bags or pallets and were handled by hand. This way of loading and discharging is very expensive and outdated by the use of the fast container cranes.

Another way of transport is bulk-wise. Because of this the sea transport costs, compared to the container trade, decrease considerably. Only several products are

suitable for this way of transporting. The material has to be free flowing and it has to be delivered in large lots to fill entire cargo holds or tanks.

Despite the high freight rates and handling costs of the container, some bulk commodities, like granule resins and coffee beans, are still transported in containers. One of the reasons for this way of transporting is the absence of alternatives. In this chapter several concepts will be discussed that can lead to an optimisation of the transport of granulates.

5.2 Boundary conditions

For the design of a new transport concept for the granule resins the following boundary conditions are formulated by HCI; the initiator of this project:

Shipments of plastics by container take place year round No receiving installations for bulk plastics available presently. Trade route: Houston to Central- and South America

Should try to transport 6-8 lots of 1000-1500 MT each lot. Should load from railcars or silos

Should discharge into silos

20 ft containers take about 17MT granule resins

Chemical tankers are always going around in the area's we are talking about

5.3 Development of concepts

To develop a new concept that fits in the boundary conditions, various alternatives have to be considered.

The following concepts are evaluated: Containers

Decktanks Cylinder tanker

Dedicated dry bulk ship with box-shaped cargo holds

A complete round trip is necessary to compare the various concepts. Containerized transport for instance does not need any investigation of a return trip because there already is a trade of containers that are transported. The other three _{concepts are} more feasible if a cargo for the return trip is available.

Chapter 5 Concept exploration

table 7 Containers

Decktanks

On several trade routes, ships still sail the return trip in ballast condition. There is no

cargo for a round trip. This is a very expensive way of shipment. If it is possible to

add tanks to

the deck, which can transport different kinds of cargo, the displacement of the ship in the return trip

will be better utilised. The use of

decktanks is feasible when there is enough extra displacement to add cargo capacity and stability requirements are satisfied.

When decktanks are attached to the deck by twistlocks they do not count for the Gross Tonnage (GT) measurement, which means no extra costs when entering a port or passing a canal.

The size of the decktanks depends on the ships size. However, it is not imaginable to ship lots larger than 2000MT per trip.

A specialized ship like a cement carrier sails from South/Central America to North America and sails back empty. If Decktanks were applied to this ship, the back trip would be more efficient. Almost all cement carriers are self-unloading and therefore have large capacities of conveying systems aboard which can support the loading and unloading of the decktanks.

The advantages and disadvantages of decktanks are outlined in table

Latin America countries. Over there, the containers are transported from the port of arrival to the consumers. The containers are sometimes filled with bags on pallets. More often containers are filled with granulate without bags in a big PE liner to protect the cargo from contamination.

This way of transporting is convenient because there is no excessive cargo handling; the cargo remains in the container from producer to consumer. The high freight rates and the high handling costs of containers in North American ports are a disadvantage of containerized transport.

The disadvantages and advantages are outlined in table 7:

Advantages

Can be loaded/discharged anywhere No additional investments Handy capacity for end-user High load-/discharge capacity

Containers

Disadvantages

High freight rates

High handling costs

Chapter 5 Concept exploration

table 8 Decktanks

The Size of the tank and the amount of cargo that us transported in the tanks depends on the ship, where it is applied to 'in table 9; two variations are outlined:

!No extra GT

Easy to install/remove

Quick and easy to build

tecktanks

Advantages Disadvantages

Small capacities

Difficult to discharge

Flexible

Combination of liquid and dry cargo

Low capacity on vessels <20,000 DVVT Difficult to install!

table 9 Two variations of the decktanks

Cylindertanker

In the early nineties, Vossnack and Wijnolst (Wijbolst941 carried out an 'innovation on the conventional chemical tanker. This concept consists of a ship outfitted with vertical cylindrical stainless steel cargo tanks that are capable of carrying: chemicals (see figure 81.

Decktanks!

On a chemicar carries' On a bulk/generall cargo vessel

Hard to combine with chemicals

Higher capacity

Deck already outfitted for twistlocks/ more space to place'

the tanks

valle4n filar

flrsmImigaminpuma/i

-

kr mot in

no

Nun ,;.in

am

7 ow MP 45 'MPMniSWJ ar:/la.lemnrii rib .11 ar. ft

rar---rstiwin dik.

ink a Pa drier

"or

P4Iiiitai

INIF :Ina l

4

r+-11.P"P 1 P

r last

r 1

v ,, At AN .,fil_R Mk., A 14 fili. Al

kl

tits

4111. a rA

Irtrimirolmwr4m9r, .4

_{itaititlAil ibikinAll Atik ILO}

,... NOW IMOOMPEIMON MO

10,

mann I

duleirpreirt-4,

annime

-not it

flt1WIS

;11 trerjers IN gPre,,M70-017

-116-eilitts.ertiaer'sresna.---62Sessi*IlEj

CYLINDER TANKER rola CHEMICALS

Chapter 5 _{Concept exploration}

The advantage of this concept is the use of the relative cheap an easy to build tanks. After the economical life of the ship, the tanks can be removed and used onshore. Cylindrical tanks are easy to clean, due to the absence of stiffeners and the fluidly round shape. This implies a reduction in slops used when transporting chemicals [Wijnolst941.

A disadvantage for this type of vessel is the increased GT of the ship. Due to the lost space around the cylindrical tanks, the ship has to be larger. An increase of about 30% of depth is needed to transport the same volume of chemicals compared to a normal chemical tanker. This results in a 30% higher GT and therefore higher voyage costs.

This increase in GT implies an increase in various costs like port and canal costs. Some insurance companies base their policy on the GT measurement. The increased safety resulted from the use of cylinders is punished by several authorities that use the GT measurement.

The increase

in GT can be driven back by piercing the tanks through the

weatherdeck. This can imply a non-watertight weatherdeck and results in more

severe rules regarding to the damage stability criteria. Measures can be taken to make a watertight weatherdeck.

A double pumping system is required if a combination of liquid and dry bulk is transported. To discharge chemicals, a dedicated deepwell pump is used.

For the handling of dry bulk a screw, pneumatic or belt conveying system can be used (see chapter 2.5). It is recommendable to install a slope underneath the tanks with an angle of 45degrs. or less to assure a free flow of the dry bulk commodity (see figure 9).

figure 9 Double pumping system in hopper tank

This kind of hopper results in a loss of space and extra weight of the tank. A decrease in the hopper angle is applicable if a vibration device is outfitted to the hopper; further investigation is necessary. Due to the regulations, it may be difficult to install a pump beneath the tanks when dangerous and inflammable chemicals _are transported as well. A flange is _{installed underneath the tank to separate the}

dangerous cargo from the rotary feeder. This flange requires some attention. It will be very difficult to operate the flange and it requires a lot of maintenance.

Chapter 5 Concept exploration

Advantages

Easy to clean

Low depreciation (tanks remain valuable) Easy and quick to build

table 10 Cylinder tanker

Nowadays parcel tankers are in fact too good to transport granule resin and thereby very expensive.

When a cylinder tanker is simply used for the transport of IMO III liquids and dry bulk, regulations are less severe, the ship will be less expensive and transport costs will decrease.

The question remains whether there is enough non-chemical cargo available in North-South America region to generate a round trip all year long.

The transport of dry bulks only, in a cylinder tanker is the cheapest concept. No special pumping systems and safety regulations have to be applied.

A second hand general cargo ship or a bulker is bought and can be outfitted with cylindrical tanks. A screw or pneumatic conveying system can be used to discharge the cargo.

Commodities that can be transported are coffee beans, sugar and granules. The various ways the cylinder carrier can be deployed is outlined in table 11:

With chemical and dry bulk

Easy to generate roundtrip

Expensive ship

Complicated conveying system

Reduction of washing time/slops used

table 11 various concepts of cylinder carrier

Dry bulkship with hatched box-shaped cargo holds

The use of box-shaped holds is efficient when large amounts of cargo need to be shipped (Approx. 30,000MT). Currently grain coal and ore are shipped this way. The holds are that large that complete lift trucks are put in the hold to gather the cargo to the conveying device that is positioned in the hold; screw, belt or pneumatic conveying device (see chapter 2.51. For the transport of sugar, a dedicated self-unloading sugar carrier was build (see figure 10). A vibration device in the bottom of the tank implies a decrease of the slope of the bottom from 45 to 12.5 degrees.

Cylinder tanker

Cylinder tanker With dry bulk only

No severe damage/safety restrictions

Cheapest ship Round trip possible? Stainless steel tanks Contamination of cargo

Disadvantages

High Gross Tonnage

Expensive ship when used for low value bulk only Commodities for a return trip

With non-chem liquids and dry bulk No severe damage/ safety restrictions

Cheaper ship Roundtrip possible! Contamination liquid with granulate

Chapter 5 Concept exploration

figure 10 Dedicated self-unloading sugar carrier

If the idea of the self-unloading sugar carrier is adjusted to transport granulates and beans a concept like figure 11 can be developed.

figure 11 Cross section of self-unloading dry bulk carrier

An approximately 12,000MT DWT ship with a length of 120 m is divided in 6or 8 cargo holds ( +/-2500cum per hold) with stainless steel walls. A screw conveyer is integrated in the bottom of the tank. This conveyer can transport the cargo in longitudinal direction through the hold. A vertical screw conveyer transports the cargo outside the ship at the front or aft of the tank. The slope of the bottom of the tank has to increase if no vibration device is used underneath the bottom.

Chapter 5 Concept exploration

table 12 Dedicated dry bulk ship

Holds in a conventional bulk carrier are made of normal steel and are integrated in the ship structure. It is very difficult to ship high value bulk in this kind of holds, there is a risk of contaminating the cargo and that is by no means allowed. The use of stainless steel tank walls is therefore recommendable. To prevent contaminating it is also possible to coat the walls of the hold with epoxy or Teflon. The use of a plastic liner that is used in the hold to prevent contaminating of the cargo with the tank walls is also a possibility

The various ways the Dedicate dry bulk ship can be deployed is outlined in table 11:

Stainless steel hold

Expensive No contamination Difficult to fin cargo for return trip

Not flexible

table 13 various dry bulk ship

5.4 Amount of cargo to be transported

Each concept has disadvantages and advantages. An important factor in the

feasibility of a concept is the amount of cargo that is transported. It is evident that a 60,000MT DWT panamax bulk carrier is not efficient to transport cargo amounts of 100MT of coffee beans; likewise, containers are not the cheapest way to transport 50,000MT of grain. figure 12 shows the range of efficient amounts of granulates roughly expressed to the various concepts.

Dedicated dry bulkship (with hatched box-shaped cargo holds)

Dedicated dry bulkship Coated hold

Cheap No contamination?

Plastic liner

Cheap

Problems with technical feasibility Easy to find cargo for the return trip

Flexible

Advantages Disadvantages

Low capital costs For large amounts of cargo only

Low transport costs Commodities for a return trip

Low CT Contamination of various cargos

Silo or bulk containers

Decktanks

Chemical carrier

Bulk/ general cargo ship

1000 2000 3000 4000 5000 (Amount of cargo[M1])

C----

_CF111111=

=NEU

figure 12 range of cargo

So the ship's size should be about the same size. In figure 12 is shown that a lot of concepts are not capable of transporting the requested amount of cargo. For containers an efficient amount of approximately 20MT is supposed; this _{is per} container. Higher amounts of cargo can be transported when a lot of containers in one shipment are used.

In the framework of this project, a cargo availability of 122,000MT a year is supposed. Also is known that the round trip takes about 45 days to sail. Thismeans

that if one ship is deployed on the trade route approximately 15,000MT of granules is transported each time. When two ships are deployed an amount of 7600MT of cargo is needed each trip. In this situation every three weeks a vessel calls a port.

Eight ships need to be equipped with decktanks of approximately 2000MT when the annual amount of cargo is transported. Those vessels are relative large and expensive ships, voyage costs will also rise when the relative large vessels call the

ports.

The idea of using decktanks is dropped because of the expected high costs compared to the other concepts.

In the next chapter the Cylinder carrier and the Dry bulk ship with box-shaped holds will be evaluated.

Chapter 5 _{Concept exploration}

Chemical cylindrical tanker

( Partly/full equiped with cilindrical tanks ) Bulk carrier

( Box-shaped tanks for granulate transport

Chapter 6 Evaluation of the concepts

6 Evaluation of the concepts

The following concepts are generated in chapter 5 and will be evaluated in this chapter:

Cylinder tanker

Dry bulk carrier with box-shaped holds

The above-mentioned concepts will be discussed and the concepts that are not feasible will be dropped

6.1

Criteria

A decision criterion has to be created to decide which concept is the most valuable. Availability of cargo, Economical feasibility, Technical feasibility and Flexibility are factors that must be investigated.

There is a large amount of granule resins that can be transported from Houston to several South American countries. Approximately 122,000MT can be transported to the three "Main ports"; Cartagena, Santos and Buenos Aires. It should be loaded from railcars or silos and discharged in silos or containers.

In the following paragraph the two remaining concepts will be checked on the before mentioned criteria.

6.2 Concepts

The cylinder tanker and the dedicated dry bulk carrier with box-shaped holds remain as valuable concepts.

Cylinder carrier

The cylinder carrier can be used for three kinds of cargo: Liquid bulk

Dry bulk Chemicals

These different kinds of commodities can be used in combination with each other. A combination of dry bulk and chemicals in a cylinder carrier is not the optimal solution.

There is a negative balance on the transport of chemicals to South American countries. The freight rates of the southbound trip are higher than the northbound trip

The transport of chemicals demands a relative expensive ship combined with the low freight rates northbound makes this concept expensive and not feasible for the transport of plastic granulates. The granulates are shipped in an expensive chemical carrier which transports granulates from the north to the south (high demand) _and uses the expansive holds to transport "cheap" chemicals on the south-north trade (low demand).

Chapter 6 -Evaluation of the concepts

It is easy to outfit a conventional 'general' cargo or multi purpose ship with cylindrical tanks. Capital costs are relatively low and flexibility is high. Partially outfitting of the cargo holds with cylindrical tanks is also an option.

A spreadsheet is developed to make a rough estimation of the ships size that calculates the amount of space needed to insert the tanks.

The input of the sheet is the cargo, capacity in cu.m, the ships length' and beam, the kind of tank and the number of rows desired. The output of the program is the depth (height) of the tanks and the mass. The height of double bottom and the distance between the inside and outside shell plating is calculated concerning the 'IMO regulations for chemical tankers (Annex II). A rough static stability check is also done. The program is shown in figure 13.

't Microsoft Excel- Tank prOperties.xls

_.11r-tand eterken Beef krvoegen tprna4 Extra Okta yenster, tin113

Hopper Bottom I 12°149312rows _!P,

1-11ank capacity (Bruto)

13 Cargo capacity,. 180001Number of tanks '(calculated) 139,00 23.00 Diameter Lpp 8 5" Number °Hanks Diameter

Design pressure (Mpa) a Design stress (N/rnm2) 71T Height D B

Hopper opening Ho raCt

figure 13 Cylinder calculations

'Commodities for a return trip 'of the cylinder carrier are desirable to decrease _the freight rates of granule resins as much as possible.

There is no chance of damaging the cargo when the ship is discharged, 'because of the closed circuit character of the discharging. procedure. No influences of weather or whatsoever are able to delay the loading and unloading procedure.

A 'dedicated high value liquid (no' dangerous chemicals) and/or dry bulk cylinder carrier seems to be a concept that is feasible to transport granulates. It is also possible to ship liquids due to the qualities of the cylinder. The advantage of transporting non-dangerous chemicals instead of dangerous chemicals is the relative cheap ship and the presence of a trade on the route that is sailed (south-northt. Because of the large amounts of oils and fats that are transported from South. American countries to the US Gulf (see chapter 3).

When liquids as well] as dry bulk are transported', a double pumping system in the cylindrical tanks is required.

It is also possible to just ship dry bulk in the cargo tanks. This 'is the lowest capital' costs solution because no double pumping system is used. Still there has to be found a commodity that is put in the tanks on the return trip. Possible cargos that can be shipped on the return trip are sugar, cacao- and coffee beans.

0,20

[240,00

11,53

, ₄₅

Not necessary, Value out of boundaries

Height of cylinder Plate thickness Total tank height Mass st. steel (MT) Depth ship (top of tanks)

U34 able 7 8,3673 .20 0 9,18 _ 0,013 11 6405 0,0100 17,5980 504,0423 19,7813 23769,00 5 93 5.34 2,63

ritirt

, A (cu.ni