to: from: mr. robertj. pellatt keithw.steeves ......1 thekvrnercb&hprocess...
TRANSCRIPT
To: From:Mr. Robert J. Pellatt Keith W. SteevesCommission Secretary Home Address:British Columbia Utilities Commission 4383 - W9th AvenueSixth Floor Vancouver900 Howe Street, Box 250 B.C. V6R - 2C8Vancouver, B.C., V6Z - 2N3
Tele.: 604-783-8528E-mail: E-mail:Commission. [email protected] [email protected]
Sir, Date: 2004. 1224th (Friday)
Re: Filing of Intervenor Written EvidenceBritish Columbia Hydro and Power AuthorityCall for Tenders for Capacity on Vancouver Island
Having checked the British Columbia Utilities Commission's Internet web sitelate last night and having found no revised Regulatory Agenda list, I must thereforeassume the December 3, 2004, Exhibit No. A-7,
To meet the Friday, 4:00 PM, December 24th12004 cutoff deadline, I submit to theCommission the following documentation as evidence for the above fore mentionedHearing process:
1.) Mr. Steinar Lynum, The Kvaerner CB & H Process, (presented at Carbon BlackWorld 96, 4-6 March, 1996, Nice, France: Intertech Conferences).
2.) S. Lynum (Kvaerner AS), CO2n free Hydrogen from Hydrocarbons, TheKvaerner CB & H Process presented at the 5th Annual US Hydrogen Meeting,March 23 - 25, 1994, PP. 6-47 to 6-56.)
I received verbal permission to submit these copies to the BCUC for these Hearingsfrom Dr. Ketil Hox, Business Manager, The Aker Kvaerner Group, Prof. Kohtsvei 15,1325 Lysaker, Norway (Tele,: +47j350_25_10, Fax.: 47735025_li, Email:Ketil.Hox @akerkvaerner.com via a 4:00 AM, Friday, December 24th,2004 telephonecall to him.
Furthermore, I understand the Commission has strict rules that restrict and/or prohibitpublished public documents as Intervenor Evidence in Public Hearings. Therefore, asqualification under this rule, I claim:
1.) The submitted evidence is proprietary in nature, and2,) It has taken me over a full year to acquire these "unique" documents via the
Vancouver Public Library Interlibrary Loan Service.
Furthermore, in conjunction with these documents, I submit to the Commission thefollowing list of copyrighted articles as further supporting evidence to support mychallenge.
References:
1.) Bjørn Gaudernack & Steinar Lynum, "Hydrogen From Natural Gas withoutRelease of CO2 to the Atmosphere," Int. j, Hydrogen Energy, Vol. 23, No. 12,PP. 1087-1093,1998.
2.) 0. Mutaf-Yardimci, A.V. Saveliev, A.A. Fridman, & L.A. Kennedy, "EmployingPlasma as Catalyst in Hydrogen Production," Int. j. Hydrogen Energy, Vo. 23,No. 12, PP. 1109-1111,1998.
3.) L. Bromberg, D.R. Cohn, A. Rabinovich, & N. Alexeev, "Plasma catalyticreforming of methane," Int. j. Hydrogen Energy, Vol. 24(1999 PP. 1131-1137.
4.) Nazim Muradov, "Hydrogen From Fossil Fuels without CO2 Emissions,"Advances in Hydrogen Energy, ed.: Catherine E. Grdgoire Padro& Francis Lau(Kiuwer Academic/Plenum Publishers, 2000: New York)
5.) E.E. Shpilrain, V.Y. Shterenberg, V.M. Zaichenko, "Comparative analysis ofdifferent natural gas pyrolysis methods," Int. J. Hydrogen Energy, Vol. (1999)PP. 613 -624.
6.) R.G. Popov, E.E. Shprilrain, V.M. Zaytchenko, "Natural gas pyrolysis in theregenerative gas heater, Part I: Natural gas thermal decomposition at a hot matrixin a regenerative gas heater," Int. J, Hydrogen Energy, Vol. 24 (1999) PP.327 -334.
7.) R.G. Popov, E.E. Shprilrain, V.M. Zaytchenko, "Natural gas pyrolysis in theregenerative gas heater, Part II: Natural gas pyrolysis in the 'free volume' of theregenerative gas heater," Int. J. Hydrogen Energy, Vol. 24 (1999) PP.335 - 339.
8.) L. Fulcheri & Y. Schweb, "From Methane to Hydrogen, Carbon Black andWater," Int. j. Hydrogen Energy, Vol. 20, No. 3 (1995) PP. 197 -202.
9.) "Plasma arc" process, Kvaerner Engineering S.A., Norway, Sec. 3 Production ofHydrogen. Internet Source: http://www.hydrogen.org/Knowledge/w-i -energiew-eng3 .html
These are the main documents presented for submission to the Commission; however,there are also other related documents as well, but are not included here.
Respectfully submitted,
- - S
Keith Vf. Steeve
2
The Kvxmer Cts & H ProcessINTERTECH
Ciftin CDnreifKes & Studies
presented by
SteinarLynumSenior Vice President
Kvrner Engineering aSs.PO Box 222
N-1324 LysakerNORWAY
presented at
yem Black World'96arbu
March, 1996 Nice, France
sponsored by
Q INTERTECH CONFERENCES
9Northbrook Dive
Portland,Maine'04 105 USA207.78(.9800 tel
207.78L2t50ftxtertethocoiir
Thfontertechusäcom
1
THE KVRNER CB&H PROCESS
SteinarLynum, Jan HugdahlandRagne Thldrum I NTERTECHKvrner Engineering a, s ufrn. Cenfrence &Sw<e
P.OBox 222
1324 Lyaaker
NORWAY
1.
INIBOD[JCTION
In 1990 Cvrner started developmentofthe innovatoy Kvarner CB&N process. Bypyrolysis ofhydrocarbon feedstock.s the process produces two valuable products, La.hydrogen and carbon black. Since 1992 a full-scale pilot plant has been operated, and thedevelopment has resulted in a technology whichnowis ready for commnrcialisation.The process is basedupon aplasmatorch integrated into a reactor system in such awaythat the basic pyrolytic process parameters for formation ofcarbon black are controlledand adjusted to allow production ofanykind of carbon black.
2.
PROCESS DESCRIPTION
Theflow-sheet of theXvrner CB&H process is shownin figure 1,In ahigh-temperaturereactor aplasma torch supplies the neccssaxy energy to pyrolyse the feedatock.Characteristic data for the plasma torch is given in table 1. The plasma torch is equippedwith a magnetic coil that enables the arc to rotate at predetermined speed. This is animportant factorto assure a homogeneous plasma gas temperature and a tow electrodeconsumption. The plasma gas is hydrogen, which is recirculated from the process. Thus,apart ftom the feed-stock and the electricity, demand ofthe plasma;torch. the process isself-sufficient.
9Narrithmok Dave
Portland, Maine04105 USA
207.78 9800 tel
207181.2 150 faxwewJntertechua.corii
nfcfljracncthu5ctcorn
2
Electteecwer
Pàtural
-*
- . :
gas
Hydrogen Consumet
Water
-.
Carbonblack
High-pressure H.steam
Figure 1
'Flow-sheet ofthe Kvmrner C&Hprocess
By direct radiation from the plasma torch as well as convection from the plasma gas, thehydrocarbon feedstock i supplied with stfficient energy to evaporate and reach thepyrolysis temperature. After the conversion ofhydrocarbons to carbon black andhydrogen is completed,,a beat-exchange system conducts the heat-transfer from the bigyam
productsto the feedatock andplasma gas, whichare pro-heated to set values,Excess heat is used to 'produce steam for external use. In large plants, it might be feasibleto use excess.heat in order to generate electricity. The recuperated process heat mutts inadecreased energy demand ofthe process.
Separation ofhydrogen and carbon black proceeds by conventional cyclones and MarsCarbon black will be distributed to markets in bulk or bags, by mad, rail or ca. Thehydrogen is preferably delivered to consumer by pipeline, whether to asingle client or to asystem servicinganetwork ofusers.
Characteristics 0!theKmerplasma torch
Characteristics ,
DataMaximum output per torch
Electrode maserlal grajahftElectrode consumption less than 0.i g/kWh -Plasma gas
hydrogen recirculated
Enthalpy, plasma gas 3 20 kV7Nm3 R
gni\fO0diverm\nlc
3
3.
WHAT MAKESTHEKVBNERCB&RPROCESSSUPERIOR AS ACARBON BLACKPRODUCIION PROCESS.
Furnace black, being the most lominathag manufacturing process of carbon black, is theonly process capable ofgiving flexibilityto adaptnewmarket requirements: However, thefurnace black process suffer form several disathrantages as low feedstock.utilizaion, highomissionsand a low-valuable processgai
By use ofa properly designed plasma gas process, the above mentioned disadvantages canbe avoided. Hence, many attempts has been made in order to utilize the plasmatechnology fur carbon black production Themain problem areas has been to controlprocess parameters as plasma gas temperature, heat transfer, flow pttemand propercontrol ofcooling cycle ofthe product stream. These parameters are essential to controlin order to achieve carbon black within close quality levels with regard to physical andchemical properties and particularly regarding graphitization lcvel.
The reported results concerning plasma based processes have basically been production ofa carbon black which exhibit ahigh or even very high degree ofgraphitization. Oftenstatements are found as:
- the temperature involved are far in excess ofthat involved in known carbonblack production processes (2).
the crystallite parameters ofthe plasma blacks differ greatly from conventionalblacks (2).
aggregates are not as forfurnace blacks
they look like "giantfllicren&', similar to ahollow ball (3),
Suchblacks arc not suitable for rubber applications and other traditional use.
To our knowledge, theKvrner CB&H process is the only plasma based process, even inlaboratory scale, which has been able to fully control the carbon blackproductionparameters, Belowwe have listed five reasons which give preferences to Kvssrner plasmabased process on the behalf of traditional fu.irnacc black processes based on incompletecombustion of fuel/fccdstøck,
*higher fcedatock efflciecy/lpwer emissions. TheCB&H process yields almost 100%efficiency concerning pyrolysis offedstbck, This high efficiency results in pure productsand lower process costs. The impurity level ofthe process is restricted t the impurities
3 introduced by the feedstock. Hence, no CO s liberated from the process and other non-hydrocarbon impurities are in the ppmlevel Using hydrogen as plasma gas and grephitas electrode material means that no impurities from the plasma torch is found in the endproduct.
nini:\t$OOdivn,.njz
4
Thenearly emission free Kverner CB&}!process makes apronounced contrast totraditional furnace black production, where fud/fèedstock combustion generates highamounts of CC) and CO along with NO and SO emissions. As a result, the process gasaccompanying furnace black can only be utilized as fuel gas. In figure 2. theKvrnerC&Hprocess is compared with the furnace black process in terms of input/exitparameters as well as process emissions.
Furnace1.7 kv Oil0.5 NMI Natural Gas kg CA,
2.7 kg a,
The Kvrner CB&H Process:1.7 Mms Natural gas4.4 kWh El. power .5 Nm' K,. 4h.1% - 1.2 kWh)
Production of carbon blackby use ofthe furnace black process andtheKvraer CB&H process
histh flexibility concerning feedstock All hydrocarbons ranging from light gases to heavyoil residues can be utilized as feedstock.This implies that the Kvrrier CJcH process canmeet demands in process plants or refineries wherethe.feedstock mix and availability ofhydrogen clean-up gases varies over the year. This diversity in fèedstock utilization is notfound in furnace black production, where heavy oil is the utilized feedstock.
A change in feedstock does only affect the product-ratio between hydrogen and carbonblack as well, as the electric power demand in order to accomplish the pyrolysis ofhydrocarbons to carbon black. This is illustrated in table 2, where the.feedstock consist ofnatural gas, decant oil or coal tar oil. The table shows that the electric energy demand perkg carbon black produced is reduced when the carbon fraction in the feedstock isincreased.
The developmentwork in the pilot plant has been focused on producing hydrogen fromnatural gas and traditional carbon black from aromatic oil, it should however be notedthat traditional reinforcing qualities are not yet produced by use ofnatural gas asfeedstock.
5
Table2 Production ofcarbon black andhydrogen from different fcdstocks (1000 kg).
Feedatock-
Electric power HydrornCarbon Black
______ _QcW) (Nm)Natural gas 30202890 820Dmt 014ecarlt oil1060970870
t'V Oiloal tar oil940- I 490920
Jhigh flexibility concernin.g production of different carbon blackoualities
In traditional furnace black production different reactor configurations are used in orderto produce carcass and thread,type carbon black. The KvmcrCB&H proceSs gives theopportunity to produce different qualities ofcarbon black within the same reactor byvarying input parameters.as reaction temperature (electric power supplied to the torch),plasma gas feed rates feedstockrate as well as location and number offeedstock injectionpoints.
Dependingon pre-set input parameters, the vzTier CB&H process is capable ofproducing different rubber black qualities ranging from N-3xx to N-7xx, thermal blackqualities as well as untraditional qualities characterized by a high degree of graphitization.Industrial black qualities are also under development, in particular towards conductiveblack production.
Figure 3 indicates how diffcrcnt'input parameter here expressedby the plasma gasenthalpy, will influence the carbon black quality,
rnsihpy
SNewqualitiesd34ZALe
1Dø A
conductive Blackd. 3.42
So A
So
Rubber Carban Black
1©OISO BET (mia)
Figure 3 Kvrner carbon black qualities as function of plasma gas enthalpy.
6
The general physical properties as well as rubber (SBR) properties ofKvarner plasmablack have also been investigated and is detailed in table 3. Thesemeasured values havebeen obtained without use of any additives in the process.
Table 3 Physical and rubber (SBR) properties
-PROPERTY Kvanjer Kvrncr kvrncx Kvmntcr I(vrnerTB N-7XX N-SXX N-3XX New gualides
Particlesize (nra) 250 715537
Nitrogensudaaraa (rn3/g)845 263570 10-30
DP Absorption (mi/100 g) 45-60 80-120 80-150 100-160 60-220
CDBP Absorption (ml/100 g) 40-55 70-90 70-100 80-110 40-100
ASTMDU9I
Modulus 300% (& IRB6) (Mpa) -3.2 0
__Pxbound +11
-2
3.42
100
The carbon black produced by the Tvrarner CB&E process is characterized by:- very clean surface with no oxygen surface groups- controlled stzuctur (vary highfhigWlow) without the use ofalkali metal sail
additions-controlled uanostrlicture level, from the traditional rubber carbon black level
to highly organized level as equivalent t acetylene black.
flower carbonbiack production costs TheCB&R process produces twovaluableproducts, La, hydrogen and carbon black. This is in contrast to furnace black processes,which only produces carbon black. Theproduction of both hydrogen and carbonblackresults in a decreased carbon black production cost when the hydrogen revenue isincluded in the calculations.
Conventional production ofH2 utilizing steam reforming ofnatural gasand release ofCO2to the atmosphere, gives ahydrogen price of0.06 USDI!'Jm3 when assuming a natural gasprice of0.032 USD/Nm3(I). However, lithe released CO2is compressed and transported
oninr00dioc1nicc
7
by pipeline to an off-shore exhausted gas well for disposal, the hydrogen cost will increaseto 0.075 USD/Nm.
Figure 4 shows the price relationship between hydrogen and carbon black for twoKvrnerCB&H plants with production capacities of 100 and500 million Nm3
hydrogen/year where the process are optimised on hydrogen production. This means forthe time being that the carbon black mainly will be applied in metallurgical industry. Theprice relationship will vary within a certain interval depending on the cost of the inputparameters, i.e. natural gas and electric power. When introducingthe hydrogen cost priceof0.075 USD/Nm3, it appears that in the large plant with upper-level input costs, thecarbon black price will be nearly 200USD/ton. Correspondingly, a hydrogen price of0.06USDINm3 wilLresult in a carbon black price ofapproximately 115USD/ton. Both carbon,black prices are considered as low within the carbon black industry.
0.14
0.12
J Plant of 100 mill. Nrn-1/y
Plant of 500 mill, Nm/y0.08
006
0.04- .. /
0.02
J H- I100 200 300 400 500Price of Carbon Black "(USD/ton)
4 Price ofcarbon black vs hydrogen for different hydrogen productioncapacities
!iügh orocess modularity. The Kvrner CB&H process is constructed on a modularprinciple. This means that the plant capacity can gradual be.increased by addingmodules. Kvmerhas engineered and cost-estimated plants with capacitiesranging from.8 360 million Nm3 of hydrogen peryear equivalent to 2000 - 90000 tonnes of'carbortblack per year. Higher production rates are easily attainable by adding more modules.
g
NEW MARKETS OR CARBON SLACK
The world wide production of carbon black i approximately 6 million tonnes, wherethe
capacity in Western Europe amounts to some I million tonnes About 90% of producedcarbon black is utilized within the rubberinduatxy(4). In figure 5 the rubber carbon blackvolume is shown forfine grade and medium/coarse grades. Theequivalent production of
hydrogen by use of theKvrner CB&H process is also indicated.
The metallurgical industry is identified as an interesting andnewcarbon black market. Thedemand within metallurgical industry for carbon black material in Europe is approximately2million tonnes. This is equivalent to nearly 8 billion Nm3H.
Petroleum coke has generally been utilized as carburiser and reduction material in thisindustry. However, pyrolyticaly produced carbon black is expected to exhibit severaladvantages compared to petrol coke The pyrolyticaly produced carbon black is fullyclean highly reactive and pulverized. The introduction of such a carbon material in themetallurgical industry will bring along several positive effects, such as reduced sulphuremission arid a reduced carbon consumption, which in turn will lead to reduced CO2emission. Utilizing a clean carbon material may also result in products containing a lowlevel ofimpurities as well as a reduced energy demand. Considering the fact that theavailability ofrelatively clean petrol coke is decreasing, makes the potential ofpyro!yticalyproduced carbon black within the metallurgical industry even higher.
Following applications ofcarbon black in the metallurgical industry has been evaluated asinteresting:
* reduction material for production ofSiC (Si, reSt)* carbon additive! carburiser to the steel- and foundry industry.
4.1
Reduction material for production of SIC (SI, FeSi)
Reduction material for the production ofSiC needs to have a high reactivity towardsgaseous Sb and to give a, high yield of quartz. Carbon Black produced by use of theKvmer CB&H process has shown excellent properties concerning these requirements.
The total production of SiC in Europe today is approximately 130 000 ton/year, with aconsumption of reduction material ofabout 150000 tort/year. By replacing all or part' ofthe total carbon (petrol coke) used in production ofSiCin the Achison process withcarbon black, a potential of 10-20% higher production yield is achieved, giving a pricelevel of> 150 USD/ton (cif).
9
4
Carbon addith'efcrburiser to the steel and laundry industry
Carbon material for this application must have properties asfast solution rate into the metal bath
high fix carbon, low level of sulphur, nitrogen, moisture, ash and volatiles
The total consumption ofcarbon additive in Europe is approximately 300 000ton/year,where high and regular qualities account'for respcctivcly20% end40% ofthe total. Highqualities includes graphite type carbon, synthstio graphite as well as calsined petroleumcoke with alow sulphur content. The price level far high quality material is > 615TJSD/ton (elf)
Regular type qualities includes petroleum type coke and metallurgical coke, Thepricelevel > 310 - 460USD/ton (elf). The level will depend upon the sulphur content, whichnormally is between 0.2 and 1,2%.
Thevolume and price estimates fbr the utilization ofcarbon blackwithin the metallurgicalindustry is incorporated in figure 5.
H2INrn " CB volume
0 Equivalent HZ production
oo
1000.
&400
law1000
800 300
800
200100
Carburization R.duUon Pin. grade umtGoare grade0
Metallurgical industry Traditional Carbon Black
Figure 5 Volume market in Western Europe for carbon black in metallurgical industryand rubberindustry. The equivalent production ofhydrogen by use of theKvrner CB&H process with natural gas as feedatock is also shown.
OOidjvere
10
5.
HYDROGEN ANA) CARBON BLACK INTERPLAY
The interplay between carbon black and hydrogenis in earliet sections described byreduced hydrogen production costs when the carbon black revenue is included in thecalculations, Such an interplay may also result in reducedCO2emissions when combiningthe CB&H process with other industrial processes. The total reduction in CO2 bycombining the Kvrner CB&f1 process with a power plant and a metallurgical process,i.e. SIC production, is shown i figure 6.
Gas electric Po~Fired Power I JMeta1lurWics ILJ
5GV*i
Stationreduction material industry
Hydrogen
I20000 75 mill. Nm' I two sotonnesL$d4ast
juuO tonnes-co2
I uaøsn
-
39MtMVWXCal
ci CarbonBaeJo'ca.r*aoey
fa toryactory 110mg-to PC~Piant -dS= ton""Z0000ton PSLi'SlOIflt +22000lin.
5. mwetø tar kd.
+20000 t_TOTAL ,
$5 000ta
Figure 6. CO2 savings when combining a gas flied power plant, vrner CS&Hprocess and processes within metallurgical industry
The hydrogen market represent nearly 400 billion Nm H2 per year which amounts to avalue of approximately 62 billionUSD. The largest single hydrogen user today is theammonia industry. Furthcr, hydrogen is utilized for the production ofchemicals likemethanol and hydrogen peroxide The largest areas ofgrowth for hydrogen lies withinproduction of hydrogen peroxide as well as within the refinery sector,
In connection with the nearly zero emission production of carbon black and hydrogen byuse ofthe CB&1-1 process, we would like to continue the non-polluting line by focusing onnew markets far hydrogen which is environmentally friendly.
12
Since combustion ofhydrogen gives only water in the exhaust, hydrogen is often denotedas the fuel ofthe future. An ideal energy chain could be represented by decomposition ofwater to hydrogen and oxygen, utilizing renewable energy from wind, sun or biomass.When power is needed on a later stage, hydrogen is consumed in afuel cell. Since
hydrogen is an energy carrier and not:an energy source, it is important to maximize the
energy efficiency in both production and consumption ofhydrogen.
7.
CONCLUSIONS
TheKvzrnerCB&H process have through extensive research and development shownthat the properties fcarbon black and the variables ofits formation such as temperature,atmosphere, flow pattern and concentration can be controlled and adjusted through theprocess by control ofthe basic pyrolytic conditions. By the control achieved on thesepyrolytic conditions aprocess is developed that make it possible to produce most oftheconventional qualities ofcarbon black on the market today as well as newqualities thathave been impossible to produce by the conventional partial combustion processes.
Beside the benefit of controlling the pyrolytic conditions theKvrher CB&}iprocessyields 100% ofthe feedatocic and does not emit any emissions to the environment. Theprocess therefore meets todays and future requirements to production processes. Theby.product hydrogen may inthe future become the main product ofthe process.
References
1. H. Audus and 0. K&rstad, Decarbonisatian offossil fuels Hydrogen as anenergy vector. To be presented at the 11 WorldHydrogen EnergyConference, Stuttgart, 23 - 28 June, 1996
2. US Patent3.342.554M.E.. Jordan at al, "Carbon black product and method ofpreparation thereof
3. 1SPC 9$, Minneapolis AUg 21-25L.. Fukheri, G. lamant, B. Variot, . Ravary, IM Ba4ie, "Characterizationof 3phase AC plasma reactor for carbon black synthesis from natural gr",
4. 1, Fauvarqu; Carbon black industry analysed, European RubberJanuary 1996, pp 28-30.
C02-free Hydrogen from HydrocarbonsThe Kvrner CB&H Process
Senior Vice president, New Technology, S.LynumKvarnerAS
Hoffsv. 1,0212 Oslo, NorwayFax: + 4722967391
5th AnnualUS Hydrogen Meeting, March 23-25, 1994
The Kvrner CB&H process yields competitive and pollution-free pure carbon and
hydrogen With any hydrocarbon and electric power as input, the hydrocarbonsdecompose into pure carbon and hydrogen at high temperature, thus avoiding CO2and other greenhouse gases.
Introduction
The innovatory CB&H process developed by Kvrner produces hydrogen and carbon blackin a more environment-friendly and economic manner than existing methods. Two valuable
products are obtained through complete conversion of the feedstock - reducing both capitaland operating costs compared with conventional processes for producing hydrogen andcarbon black.
The heart of the new process is a reactor, in which a plasma torch provides the necessaryenergy to decompose a hydrocarbon. The flexibility of the specially-designed plasma torch
permits the decomposition of every type ofhydrocarbon from methane to heavy oil.
Electric-
.
power.
C
Consumer
Consume!
Heat given offby products emerging from the reactor at a high temperature is recovered ina heat-exchanger system In large plants, it might be, feasible to generate electricity fromthis source. An almost completely pure hydrogen is sold directly to the consumer, whilecarbon black can be supplied fluffy or pelletised;
The new Kvrner CB&H process is based on a modularised concept which providesunique flexibility in terms of production capacity, availability and flexibility. Variousqualities of carbon black can be produced at the same time as the capacity easily can beincreased by adding more modules. Apart from the innovatory reactor module, the procesemploys recognised and well-proven technology.
Figure 2: Plant lay-out for production of about 360 min. Nm3 of hydrogen and 90,000tons of carbon black, annually.
6-48
From thermodynamics to commercial process
Natural gas is thermodynamically stable. Its major component is methane, with a heat offormation of 75 kI/mole. Converting methane to anything other than carbon dioxide andwater requires an input ofenergy. Alternative processes includes:
Reaction 298' 298'ki/mole kJ/moleH
cH4=C+2H2 475 38H4=>0.5C2H+0,5H2 33 66*H4+H20=>CO+3H2 249 83
CH4+2 H20 => C02 +4 E2 252 63
The Kvrner CB&H process is based on the first of these reactions. The reactionmechanism is described later in this paper.
Process flexibility
Although the process has initially been designed for feeding with natural gas, it can operatewith any hydrocarbon feedstock. Preliminary experiments were based on methane.Subsequent tests have used natural gas and other feedstocks such as propane and heavy oil.
Theprocess can operate with any refinery fuel or off gas, and converts all hydrocarbons tocarbon black and hydrogen. Any oxygen in the Eeedstok would be converted to carbonmonoxide. Changing feedstock do only affect the product-ratio between hydrogen andcarbon black. This implies that theKvrner CB&H process can meet demands in processplants or refineries where the feedstock mix and availability of hydrogen clean-up gasesvaries over the year.
A comparison of some feedstocks is given below, based on 1000 kilograms of feed in eachcase,
ProductsFeedstock Electric power Hydrogen Carbon black
(kWh)(Nm) (kg)Natural gas 2700 2662 763Fuel gas2478 2844 747Oil (C1H) 1547 1735 846
Chemical equilibrium during pyrolysis of methane
Energy consumption for decomposition of methane rises as the splitting temperatureincreases. The practical lower limit for pyrolyiic splitting of methane is assumed to beabout 700°C. However, temperatures below 1200°C give a poor methane turnover. Themain part of the feedstock is split into carbon black and hydrogen. The remainder will be
6-49
either unconverted or only partly converted during the process, and will appear asimpurities in the hydrogen gas. The graph below shows that virtually complete conversionis achieved -at temperatures above 1200°C,
Figure 3:
Chemical Equilibrium
0.90.8Q7 Hydrogen0.6 \Carbon0.5.0.4 V
/\03. ---------- Acet1ene0.20.1//\
.-.- \
0' i 'r-,---- 10
c4 c-.J - e"J- - - - - C C'J C'J C.J
CD cc co
Rco& Tempere,r/[VJ
Theplasma torch
A new and patented plasma torch has been developed to generate sufficient heat in thereaction chamber. Some characteristic data for this device are listed below:
Maximum output per torch: 8 MWThermal efficiency: 96-98%Electrode material: graphiteElectrode consumption: 0,1 g/kWhPlasma gas: hydrogen recirculated from the processEnthalpy, plasma gas: 2-20 kWh/Nm3H2
The plasma torch's high output makes it possible to operate large, rational reactors with anannual capacity of about 40 million normal cubic metres of hydrogen and 10 000 tones ofcarbon black.
High thermal efficiency and low electrode consumption means good energy utilisation anda long operating life with few operational disruptions. Using hydrogen as the plasma gasand graphite for the electrodes means that no impurities from the plasma torch are found inthe end product. As a result, hydrogen is produced to a purity better than 99.7 per cent,Even purer hydrogen can be supplied by cleaning it in a traditional pressure swingadsorption (PSA) unit,
The plasma torch operates over a wide enthalpy range. As a result, reaction zone, flowregime in the reaction chamber and splitting temperature can all be controlled to achieverational production of the correct qualities.
The diagram below shows how precisely the reaction temperature in the reactor can becontrolled.
Figure 4.-
0-60VI
10.402
00 1000 2000 3000 6000 5000 6000
Temperature IKI
The narrow bandwidth indicates that it is possible to produce extremely homogenouscarbon black qualities. Adjusting the temperature level in the reactor determines the qualityproduced.
A simulation programme for the reaction chamber has been created to support developmentwork. This takes account of flow regime, reaction mechanisms and the various aggregateconditions. The programme has made a significant contribution to development work byreducing the need for time-consuming and expensive testing in Kvrner's pilot plant.
Thepilot plant
Since 1992, much of the development work for the Kvirner CB&H process has beenpursued in a pilot plant. This facility has an annual capacity of roughly 2 000 tones ofcarbon blackand eight million normal cubic metres of hydrogen.
Initial trials consisted primarily of short test runs to confirm and develop results obtainedin small laboratory systems. More recently, the plant has been used to gain experience withlonger-term production and to optimise and verify the process on a commercial scale arid toacquire information about its continuous operation.
6-51
Hydrogen
Unlike most other fuels, hydrogen cannot be produced directly by digging a mine ordrilling a well. It must be extracted chemically from hydrogen-rich materials such asnatural gas, water or coal. When evaluating processes for production of hydrogen,accounting for the energy required is therefore an important evaluation criteria. Productiontechniques now used include steam reforming of natural gas, clean-up of industrial byproduct gases and electrolysis of water.
When evaluating Kvrner's CB&H process it is therefor essential to compare the processagainst the energy consumption and efficiency with existing processes. The figure below
gives a comparison of the energy consumption, energy efficiency and the environmentalaspects between the Kvrner CB&H process and steam reforming and electrolysis ofwater,
Figure S:
Energy Energyconsumption efficency[kWh!PJm3H2J t%J
4.0 100MOMIS
3.000
2.0 U - 0 Energy consun*fl=
1.0 70
W Energy emdency0
0.0 -.
IA
CO2 -Emission kvmerC8&H Stein, Fiectrdyneik I Nm' NJ Process
Refonner
All energy consumption for both Kvrner CB&H and the electrolysis of water is allocatedto hydrogen production. For the steam reforming process half of the natural gas isconsumed as energy in the process the remainder is converted to hydrogen.
As can be seen the electrolysis consumes more than 3 times as much energy as the KvTrnerCB&H process while steam reforming uses 2 times as much energy. Also with regard toenergy efficiency the Kvmer CB&H is superior to the two other processes.
To summarize the Kvrner CB&H is a C02-free production process of hydrogen with alow energy consumption, high energy efficiency giving no emissions ofpollutant to theenvironment. 6-52
Carbon black
Carbon black consists of extremely small particles of an amorphous carbon materialresemble snowflakes. Their consistency is fluffy.
The market for this product is rising by about three per cent annually, and currently standsat more than six million tones per year. Over 100 qualities, varying in terms of particlesize and structure, are traded.
Rubber production, particularly for vehicle tires, accounts for a major part of thetraditional carbon black market. Most of the remainder is used in paint, varnishes andtoner.
Carbon black is produced today by partial combustion of hydrocarbons, and converts only20-60 per cent of the feedstock into product.
The new Kvrner technology also opens opportunities for using carbon black in the
metallurgical sector, as both carbon riser and reduction material. This is an enormousmarket where the purity and reactivity of carbon black will offer environmental as well as
operational benefits for this industry, such as increased yield from the raw material,reduced use of electricity and lower emissions.
Today the metallurgical industry uses huge quantifies of heavy polluted coal
petroleum coaks.
Reaction mechanism/1
The mechanism described below for pyrolytic decomposition of methane is believed to bevalid for more or less any hydrocarbon, and can therefore serve as a general description ofthe process.
In principle, pyrolytic conversion of methane can be described as a step-by-stepdehydrogenation from methane - via ethane, ethene (ethylene) and ethyne (acetylene) tocarbon.
Since the thermal stability of ethane and ethene is low and the process operates at hightemperatures, the conversion to ethyne will be very rapid. Ethyne will be an importantintermediate in the conversion of any aliphatic hydrocarbon.
2CR4 C2H6 C2E4 C2H2 2 C
+H2+H2 +H2 +H2,
The reaction route shown above is a simplification of the actual mechanism. In real life,the step from ethyne to carbon is not a splitting but a polymerisation to large aromatic
6-53
hydrocarbons via benzene. The latter will be an.important intermediate in the conversion ofnaphthenic and aromatic hydrocarbons.
6CH-3C2H2-C6H6+9112
Formation of aromatics (benzene from methane) has been described above. A gooddescription of the reaction from aromatics to carbon black is provided by figure 6.
Figure 6:
Schematic mechanism of carbon -
CHI,
C2H2
"Hydrocarbon"feed stock"Cracking and polymerization
I' Cyclization 4C-CCH Polycycbc aromatic hydrocarbon
(150-660 mass units)
Condensation
ooooooSmall droplets (2-S m) (24)O.-37000 mass units)
CoagulationLarger droplets (10-20 om)
Dehydrogenation
Viscous droplets or particles
Flocculation and fusion
Fused viscous aggregates
Dehydrogenation
I Fused aggregates of carbon black
tFlocculation
i%Agglomerates,smoke sireaniers
Aromatics formed by the mechanism described above polymerise into macromolecules,PAR (polycycic aromatic hydrocarbons), which are large enough and have a sufficientlylow vapour pressure to condense at high temperature. At the right level of supersaturation,these macromolecules will condense into liquid droplets.
654
Pressure and temperature determine the concentration at which supersaturation occurs, andthereby the size of the initial droplets. Iliese are at their smallest with low pressure andhigh temperature. The droplets formed will pyrolysise (dehydrogenate) into solid particles.
During the time needed to react the droplets into solid particles, the droplets will collideand merge with each other. High temperature reduces the reaction time from liquid tosolid. A short reaction time with small droplets and few collisions will produce smallcarbon black particles. Low pressure also reduces droplet growth, since the number ofcollisions.falls because the droplets are further apart.
6-55I -
I
Literature References
1. Happel, I., Kramer, L, Ind. Eng. Chem., , 39, 1967.
2. Albright, LF,, "Pyrolysis: Theory and Industrial Practice".
3. Khan, M,S., Crynes, B,L., Ind. Eng. Chem., 2, 54 59, 1970.
4. Holmen, A. et a!., lad, Eng. Chem,, Process Des, Dcv,, jj,, (3), 439'.444, 1976.
5. Tsang, W., Hamson, R.F., "Chemical Kinetic Data Base for Combustion Chemistry.Part L Methane and Related Compounds", I. Phys. Ref Data, J. (3), 10874279,1986.
6. Homann, K.H., Angew. Chem. Internat. Edit., , 414, 1968.
6-56