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WOfflgyD MsiFOto] ffiOcSDDCBDDDCStP c Vinyl chloride monomer What you should know 30 W o CO CO u This survey of the VCM (vinyl chloride mon mer) industry, commercial dev lopments, chemistry, commercial pr cesses and new developments indicates that VCM can remain c mpetitive with rising crude costs ( W. McPherson, C. M. Starks and G. J. Fryar, Continental Oil Co., Ponca City, Okla. Development of the vinyl chloride monomer (VCM) industry has been closely interrelated with the polyvinyl chloride (PVC) industry. Effectively 96 percent of the VCM production goes into the manufacture of PVC. Therefore, technological advances in one area have significant impacts upon the other, producing a domino effect. This, in conjunction with increasingly tighter en vironmental regulations, has insured a continuing evolu tion of VCM technology. It is timely to review the state of the art. INDUSTRY PROFILE The commercial significance of vinyl chloride monomer (VCM) can be highlighted by the statistical ranking of the 19th largest chemical commodity in the United States. Turning our view upstream, we realize the significance VCM plays in wedding the petrochemical and chloroalkali industries. Fig. 1 schematically depicts the U.S. market integration surrounding VCM. Pondering the posture individual companies present to the market (Table 1), one can muse as to the motivational forces behind their respective business strategies. It holds that, if 96 percent of the VCM demand in this country is derived from PVC, then VCM's future is inescapably tied to that of PVC's. Within the scope of known-unknowns, one basic fact attests to its longevity. On an energy-equivalent basis, PVC is one of the most energy-efficient construction materials available (Table 2). This follows even after weighing the socioeconomics of health and environment. Looking at the two principal components of the PVC ' " ffTwni \' . ' BBrriinnAe T ' electricity ` Chlorinated hydrocarbons Hydrocarbon L '*L: ^K ."..rf-n.-.vV's.:-y "J "_" ,l':> i.&zk . x A,, ' . . NaOH/CI, ' t <- >, , .Vw.' ' 20-22% E DC 87% VCM i 12-13% * >< ',5 . Fig. 1--Shows the U.S. market integration surrounding vinyl chloride industry. Hydrocarbon Processing March 1979 ^ Wsrr^ 88-93% PVC 3^- Export ............... ^ /.J''./i .- -. 75 R&S 104935 VINYL CHLORIDE MONOMER market, flexible or plasticized products, of which fabric for automobile interiors and electrical wiring insulation are examples, and rigid products, including sewer and water pipes, electrical conduits and shoe soles, we find the rigid aggregate growing at 9 percent per year, as opposed to the flexible area which is increasing at a rate of approximately 5 percent. Within the past few years, the rigid aggregate has surpassed the size of the flexible market which can be witnessed by the creeping seasonal response the VCM industry has to construction, the major end-use outlet for rigid products. Wood PVC Steel Aluminum Copper Fig. 2--Relative energy content of various construction materials. TABLE 1--Nameplate capacities (MM pounds) Borden................... Con-, co................... Diarond................. Dow....................... Ethyl...................... B. F. Goodrich.......... ICI........................ Monrchem.............. PPG ..................... Shell...................... StauPer.................. PVC 550 550 None None 175 1,100 None None None None 420 VCM 300 700 1,000 2,250 300 1,100 300 300 900 1,540 170 Ethylene None 650 None 4,800 None 350 None None None 2,700 None Chlorine None None 2,500 8,400 500 250 300 ' None 2,900 200 780 TABLE 2--Commercial types of VCM technology I. High Purity Acetylene Feedstock II. Dilute or Mixed Gas Feedstock III. Balanced Ethylene Feedstock A. Air-Based Oxychlorination B. Oxygen-Based Oxychlorination Developer/Licensor Dow..................................... Ethyl, ICI, Solvay............................... B. F. Goodrich.................................... Kureha...... Mitsui Toatsu. Monsanto................ PPG........... Rhone Poulenc Stauffer............ Tokuyama Soda .. ToyoSoda............. Hoechst................... ICI......................... Technology Basic Oxychlorination III A III A III A,B II III B III A,B III B III A III A,B III A III A 1 1-- Over the course of the past ten years, VCM has be come a major item of international commerce, with the United States the architect of this business. Between 1975 and 1977, eight percent of the VCM produced was carried offshore, making it third only to styrene monomer and toluene in the generation of trade dollar's by a chemv'' cal commodity. This factor has tended to fill in the vataL in demand brought about by construction. More si^^B cantly, it has permitted the VCM industry to consistently operate near capacity levels by exporting domestic sur pluses into the world arena. Looking at the global VCM market, we view forces at work changing the disposition of trade. Beginning within the past five years, Europe as a whole has swung from a net importer to exporter of VCM. With ten billion pounds of VCM capacity integrated to where there is less than 15 percent merchantly derived PVC demand, producers are now chal lenging U.S. material for a share of the remaining world exports. Japan, whose five billion pound VCM industry was built to serve the whole of the Asian-South Pacific market, first in PVC and then later in VCM, has witnessed a major influx of U.S. and now European monomer pro ducers into their domain. The present situation in the U.S. is manifested by cheaper feedstocks, vis-a-vis energy, and an undervalued currency that together are able to offset logistical costs and remain competitive in the consuming markets. Eventually, merging energy parity and emission cost pass throughs will leave U.S. VCM no more competitive than that of any other nation. We conclude, therefore, that exports will continue as developing third world markets seek to establish a plastics industry in advance of petro^ chemicals. Conversely, the major market imbalances'^ the past have gone by the wayside, and market gro^H will come from the domestic sector. Fig. 3 depicts me longer term outlook for VCM. In making our projections, we assume that the growing capital commitment required to make VCM will not force PVC to become uncompeti tive with alternative products. Secondly, we foresee no major technological innovation on the horizon that could radically alter the economics of production. We do see, however, technological improvements of degree that di rectionally level out the inflationary trend of plant con struction. Within the U.S., we project a 700 to 1,000 MM lb. per year grass roots plant will be required every two years to meet demand. It is within the scope of this time frame that innovation will be tested. COMMERCIAL DEVELOPMENT VCM was first produced commercially in the early 1900s via reaction of HC1 and acetylene derived from calcium carbide. VCM usage in the manufacture of syn thetic rubber accelerated dramatically during and after World War II. This increased demand prompted searches for more economical hydrocarbon feedstocks. Acetylene was recovered from refining steps, and new technology was developed to produce acetylene specifically from hydrocarbon cracking. Ethylene became plentiful in the early 1950s. Dirjfl chlorination processes to produce 1,2-dichloroethtnB (EDC) from chlorine and ethylene were developed in 76 March 1979 Hydrocarbon Processing R&S 104936 conjunction with EDC cracking technology to yield VCM. This process yielded byproduct HC1 and did not pro liferate immediately, except in conjunction with acety lene-based technology which needed HC1 to produce VCM. CIn the U.S., ethylene production from abundant suplies of low cost LPG began to predominate. In Europe, ethylene prices also continued to drop, though not to the same degree since higher priced. naphtha and gas oil were the primary feedstocks. Therefore, while European producers continued to use acetylene-based VCM tech nology, American companies moved rapidly to ethylenebased technology. With the startup in 1958 of the first large scale oxychlorination process to yield EDC from HC1 and ethylene, a new era in VCM technology began. This "balanced" process allowed production of VCM from two commodity chemicals, chlorine and ethylene, without voluminous byproduct HC1. VINYL CHLORIDE CHEMISTRY Large scale production of vinyl chloride was first done by addition of hydrogen chloride to acetylene: Pig. 3--U.S. vinyl chloride nameplate capacity versus demand. Hydrochlorination of acetylene Catalyst HC1 + HC = CH ------------- * HC* = CHC1 (1) However, much lower costs for production of ethylene than acetylene and the discovery that 1,2-dichloroethane (EDC) thermally decomposes to vinyl chloride in excel lent yield led to the following reaction sequence as the predominant manufacturing method for VCM: Direct chlorination of ethylene CH* = CH* + Cl* - C1CH*CH*C1 EDC cracking to VCM Heat C1CH*CH*C1 --------- CH* = CHC1 + HC1 This method was especially advantageous for those producers having a use for the HC1 by product, particu larly so if acetylene were available; since then, a bal anced VCM process with no coproducts could be op erated. Later, the discovery that oxychlorination technology could be applied to ethylene to give 1,2-dichloroethane in high selectivity now allowed a completely balanced process based only on ethylene and chlorine as feedstocks. Oxychlorination of ethylene Catalyst CH* = CH* + 2HC1 + 1/20* ------------- CICH*CH*C1 + H*0 At present, about 92 percent of the vinyl chloride pro duced in the United States is from plants that use the balanced process based on ethylene via chlorination, oxychlorination, and thermal cracking of EDC.1 These hree separate steps are described in greater detail below. Additionally, the hydrochlorination of acetylene is also discussed below since plants using this chemistry are still in operation. Moreover, some recent crude oil cracking technology may narrow the cost gap between acetylene and ethylene with consequent revival of interest in VCM from acetylene. Some chemistry on direct preparation of VCM from ethane is also briefly outlined. Direct chlorination of ethylene. Direct chlorination of ethylene to 1,2-dichloroethane is almost always conducted in a liquid phase reactor by intimately mixing ethylene and chlorine in liquid EDC. Ferric chloride, a highly efficient and selective catalyst for this reaction, is normally used in commercial processes. Amides, such as n,ndimethylformamide, have been reported to increase PVC selectivity.2 Oxygen, frequently present as an impurity in chlorine, likewise increases EDC selectivity in direct chlorination of ethylene by inhibition of free radical re actions that give 1,1,2-trichloroethane. Direct chlorination reactions may be run rich in either ethylene or chlorine, depending on the methods available to the plant for handling offgases from this reactor. Con version of the lean component is usually 100 percent, and selectivity to EDC is greater than 99 percent. 1,2-Dichloroethane, as it comes from the direct chlori nation reactor, is frequently of sufficient purity for crack ing, except that it may contain ferric chloride, which would lead to rapid fouling of the cracking reactor. To avoid expensive purification of this already pure EDC, one may remove FeCl.-, by adsorption on activated carbon3 or other solids.4 Alternately, one may operate the direct chlorinator at the boiling point of EDC, taking pure EDC overhead and using the heat of reaction to supply the heat for vaporization.5,0,1,8 Oxychlorination Of ethylene to EDC. Ethylene oxy chlorination is normally conducted at temperatures of 225-325 C and at pressures of one to 15 atmospheres. Catalysts for this reaction almost always contain copper chloride and sodium or potassium chloride deposited on alumina or other suitable support. The detailed mech- Hydrocarbon Processing March 1979 VINYL CHLORIDE MONOMER anism of the catalyst's activity is not known, but it is recognized that cupric chloride is the active chlorinating agent. The cuprous chloride produced is rapidly recon verted to CuCl under the reaction conditions, but the presence of some cuprous chloride is thought to be advantageous because it complexes with ethylene, bring ing it into contact with CuCU for a long enough time for chlorination to occur. The sodium or potassium chloride serves to increase EDC selectivity, mostly by inhibiting formation of ethyl chloride. Other catalyst components, such as rare earth metal chlorides, sulfate salts, ferric chloride and numerous other additives, have been de scribed in the patent literature. Good temperature control of the highly exothermic oxy reaction is a key element in successful production of 1,2-dichloroethane. Temperatures higher than about 325 C lead to increased byproduct formation, mostly through increased dehydrochlorination of EDC to vinyl chloride followed by additional oxychlorination to give products having high levels of chlorine substitution. High temperatures also increase the amount of ethylene burned to carbon monoxide and carbon dioxide. Of equal im portance, high temperatures deactivate the catalyst by highly accelerated coking and consequent powdering of the catalyst units and by increased sublimation of copper, Chloride away from the catalyst. Temperature control in fluidized bed reactors is main tained by the excellent intermixing of the catalyst par ticles and by use of internal cooling surfaces.10 Tempera ture control in fixed bed reactors is more difficult since "hot spots" tend to develop. To keep the hot spot temperature below below 325 C, yet get maximum utilization from the reactor, it is common practice to pack the reactor tubes with active catalyst and inert diluent mixtures in proportions of each so adjusted as to have low catalyst activity at the inlet, steadily in creasing to maximum activity at the outlet. This grading of the catalyst activity flattens the temperature profile, allowing for good temperature control with high produc tivity. For example, one patent indicates the use of four zones with 93 percent, 85 percent, 40 percent, and 0 percent, respectively, of the active catalyst pellets replaced by inert graphite. As an alternate to using inert materials in the catalyst bed, catalysts, each with higher levels of CuCl- and consequently of increasing reactivity, are sometimes used. Fluid bed oxychlorination of ethylene, operated under good control, results in 94-97 percent ethylene conver sion, 95-97 percent HC1 conversion, and EDC selectivities in the range of 94-96 percent. Fixed bed oxychlorinations are normally run with excess ethylene relative to HC1, resulting in 93-97 percent ethylene conversion, 94-95 percent HC1 conversions, and EDC selectivities of 93-95 percent. These data do not include recovery of excess ethylene in subsequent reaction steps. Excess ethyl ene in vent gases from oxychlorination is normally con verted to EDC by direct chlorination with chlorine,11,13 although, if oxygen is used rather than air, the excess ethylene may be recycled directly back to oxychlorination. Byproducts of ethylene oxychlorination are- vinyl chic-, ride, ethyl chloride, 1,1-dichloroethane, vinylidene chlo ride, cis` and trans-1,2-dichloroethylenes, trichloroethyl ene, chloroform, carbon tetrachloride, methyl chloride, methylene chloride, chloral and high boiling compounds. All of these byproducts present problems in one way or another, such that their production needs to be minimize '' to lower raw material costs, to lessen the difficulti^B. preparing pure EDC, and to prevent fouling iiBne cracking reactor. Chloral, in particular, needs to be re moved since it polymerizes readily in strong acids to give solids which clog and foul operating lines and controls. One must also take care to see that the feeds to oxychlorination are pure. Normally, the only problem is with low levels (0.1 to 0.5 percent) of acetylene present in the HC1 from cracking of EDC. Acetylene in the feed leads to the formation of considerable highly chlorinated byproducts and tars. Selective hydrogenation of this acetylene to ethylene and ethane is practiced by many companies.15 Oxychlorination with oxygen instead of air. Use of oxygen instead of air for ethylene oxychlorination has received much attention.14'1 The outstanding benefits from using oxygen are avoidance of expensive facilities to recover EDC, ethylene and other chemicals from the large nitrogen vent gas stream; a large reduction in the quantity of offgases that will probably need to be in cinerated; and the ability to use ethylene as a diluent for oxychlorination, a procedure said to improve heat transfer in tubular reactors. Purification of EDC for cracking. Great care mus^L taken to ensure that EDC used for cracking to chloride is of high purity, normally greater than 99.5 per cent, since cracking is exceedingly susceptible to inhibition and fouling by trace amounts of impurities. Additionally, the EDC must be bone dry to prevent excessive corrosion downstream of the cracker. For these purposes, one must consider removal from EDC of byproducts from three sources: EDC from direct chlorination, EDC from oxy chlorination, and EDC recovered from the cracking step (see below). EDC from direct chlorination is usually quite pure, greater than 99.5 percent; and, except for the FeCl3 present, it needs little further purification. As mentioned previously, ferric chloride may be removed by adsorption on a solid, or the EDC may be distilled away from FeCl3 in a boiling reactor. Alternatively, the ferric chlo ride may be removed by washing with water, usually in conjunction with oxy-EDC. 1,2-Dichloroethane from oxychlorination contains a variety of impurities as listed previously. EDC from this source is usually washed with water and then with caustic solution to remove chloral and other water extractable impurities.30 Low boiling impurities and water are taken overhead in a first (light ends) distillation column, and then pure dry EDC is taken overhead in a second (he ends) column. EDC recovered from the cracking step contains an R&S 104937 78 March 1979 Hydrocarbon Processing appreciable number of impurities, of which two, chloroprene and trichloroethylene, are not readily removable by distillation, necessitating the use of other treatments. Chloroprene, if not altered by chemical treatment, con centrates in the light ends column where it can polymerize to solid or rubbery materials which seriously foul and Cpset this column. Trichloroethylene forms an azeotrope with EDC, boiling very close to EDC. If it is not removed in some way, it accumulates in the EDC, leading to re duced cracking rates and increased fouling. Both impuri ties may be removed by subjecting the recycle EDC stream to chlorination prior to distillation,21'23 Treatments with HCI24'20 and by hydrogenation27 have also been patented as methods for removal of chloroprene. Cracking of 1,2-dichloroethane to vinyl chloride. At temperatures in the range of 425-550 C, and near at mospheric pressure EDC undergoes clean thermal dehy drochlorination (cracking) to yield vinyl chloride and hydrogen cloride: Heat C1CH2CH,C1 ---------- CH, = CHC1 + HC1 The mechanism of this reaction has been extensively investigated28 and shown to involve a sequence of free radical intermediates. Use of pressure up to 25 to 30 atmospheres during cracking at temperatures of 500-550 C provides better heat transfer, reduced equipment size and easier separa tion of HC1 from the product by fractional distillation. EDC conversion levels are normally maintained in the range of 50 to 60 percent at residence times of 2 to 30 seconds, with selectivities of VCM ranging from 96 s *o 99+ percent. Some byproducts generated during crack le .ig act as inhibitors to the free radical sequence so that increasing severity leads to smaller and smaller increases in EDC conversion with correspondingly increasing levels of byproducts. Various materials, such as chlorine, bro mine, or oxygen have been shown to be initiators for EDC cracking.28 Recently, however, exclusion of oxygen is claimed to result in considerable reduction of fouling on the cracker tube walls.20 A rather spectacular claim has been made that use of nitromethane as an initiator provides EDC conversion levels of up to 92.5 percent at 480 C.30 An important processing requirement in EDC cracking is rapid cooling or quenching of the re action mixture. If cooling is done too slowly, substantial yield losses to heavy ends and tars result.25,30'31 Byproducts from the cracking reaction include acetyl ene, ethylene, methyl chloride, butadiene, vinyl acetylene, benzene, chloroprene, vinylidene chloride, 1,1-dichloroethane, chloroform,. carbon tetrachloride, 1,1,1-trichloroethane and other compounds. Most of these impurities remain in the unconverted EDC fraction and are re moved when this stream is distilled. Ethylene and acety lene codistill with the HC1 and are thus routed back to oxychlorination (after optional hydrogenation of the acetylene to ethylene). Methyl chloride and butadiene more or less codistill with the vinyl chloride, depending on the efficiency of the VCM fractional distillation sys tem. Addition of chlorine or carbon tetrachloride to the rackcr feed is claimed to suppress methyl chloride formation.33 Removal of butadiene, a contaminant which can interfere with polymerization of VCM, has been done by treatment with chlorine,34 anhydrous HC1,35 or selective hydrogenation.30 HCI addition to ac tylene. Recent development of a new crude oil cracking process27 using very high tem perature steam (2,000 C) as a heat transfer fluid pro duces substantial yield of acetylene along with ethylene. Under some economic and geographic conditions, the use of this cracking process may be advantageous and may, thereby, provide acetylene for vinyl chloride pro duction. Typical conditions of hydrogen chloride addition to acetylene are total pressures on the order of five to 15 atmospheres, temperatures of 150 to 180 C, and use of a mercuric chloride-on-carbon catalyst.38 With stoichio metric quantities of reactants, essentially 100 percent con version is observed with VCM selectivities on the order of 98 percent. It is notable that ethylene does not react under these conditions, thereby allowing the use of mixed ethylene-acetylene streams as feeds. Ethylene, easily re covered from the vinyl chloride product by fractional distillation, is then chlorinated to yield 1,2-dichloroethane Other catalysts have been shown to be effective for addition of HCI to acetylene, but HgClj is vastly supe rior.30 However, in addition to the general toxicity prob lems involved in working with mercury-containing substances, HgCl2 has appreciable volatility under the above reaction conditions leading to a need for consider able care and control in operation of the reactor. In fixed bed operations, HgCU vaporizes from the hot spot of the reactors, condenses at cooler locations downstream and results in continuous movement of the hot spot downstream with eventual loss of catalytic activity. This loss is minimized by periodic reversal of flow through the reactor. Ethane-based vinyl chloride processes. A number of patents dealing with chemistry for conversion of ethane to EDC and/or VCM have been published in recent years.40-44 Most of these reactions involve high tempera ture oxychlorinations, such as CuCl2 Catalyst CH3CH3 + HCI 4- 02 350-450 C CH3 = CHC1 -I- 2H-0 However, these processes suffer from a number of dis advantages, the most important of which includes low selectivities, low conversions and difficult operating con ditions such as CuClj sublimation. One reaction system based on ethane, called the "TRANSCAT" process, has been developed on a large pilot plant scale but is not yet in commercial practice.45'53 The chemistry of this process is a complex series of re actions, generally involving chlorination, dehydrochlori nation and oxychlorination. A mixture ofTethane, eth ylene, ethyl chloride, chlorine and HCI are fed to a melt of cupric oxychloride and potassium chloride, yielding vinyl chloride, water, and cuprous chloride as the main products. The cuprous chloride-potassium chloride prod uct is taken to an oxidation reactor where the cupric oxychloride is regenerated by treatment with air. Vinyl chloride is separated from the organic product and puri- R&S 104938 Hydrocarbon Processing March 1979 79 R&S 104939 VINYL CHLORIDE MONOMER fied by fractional distillation. Removal of about 0.4 per cent butane plus butenes present in the main VCM cut represents a very difficult separation.45 Ethyl chloride and ethylene can be recycled into the feed. Chlorine values in the chlorinated byproducts can be recovered by incineration and then feeding these gases to the cuprous chloride oxidative regenerator reactor. Disposal of byproducts. Disposal of byproducts pre sents special problems for vinyl chloride manufacturing plants, since a variety of gaseous organic liquid, and acqueous streams must be handled, each with its own particular problems. Vent gas streams from various units may contain small amounts of HC1, chlorine, ethylene, vinyl chloride, methane and carbon monoxide. These streams may some times be treated by scrubbing, chemical treatment, sorption, or other methods to recover some chemicals when economically justified. Otherwise, the common cleanup technique is either incineration or catalytic com bustion followed by recovery of HC1 from the vent gases. Two organic byproduct streams are produced. The light ends contain mainly ethyl chloride, cis- and trans1,2-dichloroethylene, chloroform and carbon tetrachloride. The heavy ends or "tars" contain mostly 1,1,2-trichloroethane, lesser concentrations of tetrachloroethanes, chlori nated butanes, chlorinated aromatics and a large number of other compounds present in small amounts. These streams are normally fractionated to recover useful com ponents, the others incinerated to recover chlorine values either as aqueous or anhydrous HC1. Process water streams are steam stripped to remove volatile organics followed by neutralization and then treatment in an activated sludge system to remove non volatile organics in the water.45 COMMERCIAL PROCESSES Broadly speaking, there are three types of VCM pro cesses in commercial use today. These are categorized as acetylene, ethylene, or mixed gas based on feedstock re quirement. Within the "ethylene-type" plants, further classification is desirable to distinguish the type of oxychlorination technology used, i.e., oxygen versus air feed stock (see Table 2). Over 90 percent of the world's listed 35 billion lb. per year VCM capacity currently is based upon the balanced ethylene feedstock route. Of this, just under 90 percent uses air-based oxychlorination. How ever, of the projected worldwide plant startups for the period 1979-1981, approximately 30 percent of the 7.7 billion lbs. per year VCM will be derived from oxygenbased oxychlorination. Other existing producers will un doubtedly be evaluating the conversion of present airbased plants to the use of oxygen during this time frame. Table 3 presents a summary of the technology sources in use today. It is thought that the technology currently licensed by ICI and Solvay is similar to the process normally attributed to Ethyl. Therefore, all are listed under Ethyl's technology. It is interesting to note that several plants exist where the oxychlorination process TABLE 3--Current VCM t chn I gy sources Existing VCM, Technology Source Plants MM Lbs./Yr. 1. B. F. Goodrich__ 2. Hoechst/BFG*.... 3, Stauffer/BFG*__ 4, Stauffer............. 5. Ethyl,Solvay, ICI.. 6. Dow.................. 7. PPG.................. 8. Rhone-Poulene... 9. Monsanto........... 10. Toyo Soda.......... 11. Tokuyama Soda... 12. Mitsui Toatsu...... 13. Kureha.............. 14. Miscellaneous..... 18 11 5 19 14 7 5 5 4 3 2 3 2 10 5,840 4,290 2,360 6,390 5,000 3,040 1,700 1,330 1,110 400 660 610 410 2,400 107 ^5,540 Planned (1979-1981) VCM, Plants MM Lbs./Yr. 4 2,160 2 580^ 2 350TM 1 260 3 1,050 3 1,780 1 500 1 250 1 330 1 90 ---- 1 330 20 7,680 * Oxychlorination process provided by BFG. of one licensor, B. F. Goodrich, has been combined with direct chlorination and VCM technologies of others, i.e., Hoechst and Stauffer. Table 4 presents a tabulation of worldwide VCM producers. This summary was prepared from scores of literature sources, some of which were contradictory. However, the authors have exercised their best judgment in the absence of specific information from the listed licensors. The reader is referred to Leonard,54 Gomi,53 or Sittig55 for details of the acetylene and mixed gas routes to VCM. The technology discussion herein will be limited to the balanced ethylene feedstock route used overwhelmingly today. / Although each of the major technology licensors many patents, none has complete coverage of each st^ of his process. As a result, the sequence and type of operating steps tend to be very similar from process to process. The basic differences stem from the oxychlorina tion technology and the types of impurities appearing in the crude EDC- The licensor, therefore, provides process know-how primarily, as opposed to patent position. As a result, published literature by major licensors is under standably very sparse and highly simplified, with certain exceptions.53,5?-58,50 TYPICAL VCM PROCESS The typical VCM process combines direct and oxy chlorination (oxy) processes to provide 1,2-dichloroethane (EDC) feedstock for the EDC pyrolysis unit (see Fig. 4). The direct chlorination process relative to oxy is char acterized by low capital investment, low operating costs and high purity product. However, HC1 generated from the EDC pyrolysis unit dictates the use of an oxy unit. With the current pyrolysis yield of approximately 0.55 mol VCM per mol EDC fed, and the HC1 yield of 1 mol per mol VCM, the oxy unit size is set at approximately 0.5 mol EDC per mol of VCM desired. This sets the direct chlorination unit size at approximately 0.5 EDC per mol VCM. The combined EDC streams are caustic treated to re 80 March 1979 Hydrocarbon Processing n c R&S 104940 Fig. 4--Typical vinyl chloride monomer block/flow diagram. Direct chlorination `'*''"X',,iH":!5'.5wTM -','s-.;77 **??'";'``*"'*.^;i-''.'-O>i'Oveiyhelholroinrinatitoionn:!. Reactor . ' .;*** i, ' 1 *. ",,>{***'* > ">v^1-.-.. _R_e_acto2-r>i''*i`J'-v ^Reactor .' Reactor - ., . j -rty#.-; .*y 'rtii'.i. c 7 > i'~' - Jr/-\,^^4vk/ j*S; ' y,' , . *<- ,, :* ~2k ,r .V cw ,y,j..*. 'kr ` k & '.Vv .-'. ' ,t > - " *:_.tjX'j*j>C1*V','. I ' ' TT V^s Ref - >'<' >* .'.'"'?y.'..w .-y't'ra'l * V ' * u c EDC purification Fig. 5--Schematic of the Stauffer vinyl chloride monomer process. Hydrocarbon Processing March 1979 i/ 81 TABLE 4--VCM plants--worldwide--(cont'd) Operator Italy Anic Montedison Rumianca Sud SARP Sincat Solvic Sir Consonio Industries Japan Asahi Penn Chiba VCM Chisso Oenki Kagaku Japanese Gcon Kanegafuchi Kanegafuchi Kashima VCM Kureha Mitsubishi-Monsanto Mitsui Toatsu Nissan Ryo-Nichi Co., Ltd. Sanyo Monomer Shunan Petrochemicals Sumitomo Sun Arrow Chemical Toyo Gosei Toyo Soda Korea Korea Pacific Korea Pacific Libya GNOI Mexico Pemex Morocco SNEP Norway Norsk Hydro Peru Sociedad Paramonga LTOA. Poland Polimex-Cekap Portugal CNP Rumania Industrial Import State Authority South Africa Africa Explosives and Chemicals Spain Monsanto Rio Rodano Vinielor Dow Sweden Kemanobel Switzerland Lonza Taiwan Formosa Plastic Chung Tai (7) Turkey Petkim Petkim United Kingdom British Petroleum ICI USSR Techmashimport Venezuela Petroplas Yugoslavia Hemijska Ind. Dow/I na Location Ravenna Brindisi Porto Marghera Cagliari Cagliari Rayamino Porto Torres Chiba Chiba Minimota Takaoka Takasaga Takasaga Kashima Nishiki Yokkaichi Nagoya Osaka Chiba Mizushima Mizushima Tokuyama Nlihama Tokuyama Tokushima Tokuyama City Yokkaichi Yeo-Su Ulsan Abu Kammash Pajaritos Pajaritds Mohammadia Ralnos Paramonga Wloclawek Sines Rimnicu Vilcea Rimnicu Vilcea T Sasolburg [ Sasolburg Tarragona Tarragona Tarragona Tarragona Huelva Martonell Huelva Stenungsund Lalden Keohsiung Toufen Yarimca limit Aliagi-lsmir Baglan Bay, Wales Hillhouse Runcorn Djerjinsk Gorki Gorki Kalush Volgograd Zima El Tablazo Skopje Pancevo KRK Process A/-/m/a/o M/A/O E/-/D E/A/O AE/-/D E/A/B E/A/B E/A/B M/-/0 AE/A/AE/A/O E/A/B AE/A/O A/-/E/A/B E/A/O e/a/B E/A/B E/A/B E/A/B E/A/O E/O/B Planned E/O/B E/-/D A/-/- E/A/B E/A/B AHE/A/B E/O/B/ EHO AE/A/O AH- E/A/B m E/A/B E/A/B E/A/B Startup Year** 1971 1969 1970 1965 1976 1967 1971 1967 1969 1970 1970 1964 1970 1964 1970 1968 1970 1970 1968 1967 1966 (1979) (1980) 1978 1976 1978 (1979) (1981) 1968 1978 (i980) 1970 (1981) 1967 Lictnaor Stauffer BFG BFG PPG PPG Ethyl Solvay Sir PPG Stauffer Toyo Soda Denki Kagaku Japanese Geon Stauffer Stauffer BFG Kureha Monsanto Mitsui Toatsu Mitsui Toatsu Toyo Soda BFG BFG Tokuyama Soda Stauffer Tokuyama Soda Toyo Gosei Toyo Soda Toyo Soda Dow Dow BFG, Hoochst Monsanto BFG Stauffer BFG, Hoechst Vulcan PPG Dow Mitsui Toatsu ICI, Solvay Tenneco Monsanto Monsanto Monsanto Rhono-Progil Solvay Dow Stauffer 1973 (ini) 1971 1970 1974 (1979) 1977 (1979) (1981) Stauffer Mitsui Toatsu Solvay ICi, Solvay BFG Solvay Solvay Rhone-Progil Stauffer Rhone-Progil BFG, Hoechst Kureha BFG, Hoachst BFG Rhone-Progil Stauffer Dow Engineer/ Contractor Foster Wheeler Opt. Solas Euteco Solvay Euteco Sumitomo Hitachi Sumitomo Kanegafuchi Chiyoda Toyo Engi'ncering Toyo Engineering Hitachi Hitachi Fluor/DacUm Proeon F. Uhde, Salzgitter Lummus Bufete Krebs Badger Petrocarbon, Davy-Powergas Klock Toyo Enginaaring Humphries & Glasgow Crawford-Russol Lummus McKee, CTIP McKee, CTIP McKee, CTIP Lurgi Humphreys and Glasgow CTIP C. F. Braun C. F. Braun Speichim Speichim Speichim F. Uhde Chiyoda F. Uhde Foster Wheeler * Information tabulated from many source). In cases (several) of contradictory reports, authors have eiercised their best judgment. ** Parentheses denote that plant is thought to be in engineering and/or construction stage and has not reached an operational status. Legend: Hydrocarbon Feedstock (E)thylene (A)cetylene (M)ixed Cas / Oxy Basis (A)ir (O)xygen / Process (Balanced (0)xy (O)irect VCM Capacity, MM Lba/Yr** ^ ~ -A 400^^ 400 390 350 (110) 290 110 310 99 350 220 (330) 257 331 331 770 269 130 130 130 73 440 238 440 180 220 88 no 220 (330) 132 (136) 155 440 99 660 17 (450) / (330) 88 ^ 390 60 440 176-330 (250) 530 220 (500) 265 (770) 180 44 530 (530) 119 (257) 573 66 73 68 550 145 (595) 110 110 (220) (440) 82 March 1979 Hydrocarbon Processing R&S 104942 VINYL CHLORIDE MONOMER TABLE 4--VCM plants--worldwid Operator nited States C ICI America Conoco Chemicals Dow Ethyl Corp. B. F. Goodrich Monochem PPG Shell Chemical Stauffer Borden Chemical Georgia Pacific Diamond Shamroch Algeria Sonatrach Argentina Dow Qulmica Electroclor Australia Iciam Belgium BASF Ubechem Limburgse (LVM) Solvic Brazil Copamo Monomers Vinihcos Petroouim Camacari Bulgaria Technocomplekt Canada Dow Shawinigan Chile Petroquimica Oow/ENAP China Technical Import Corp. c Colombia Petroquimica Columbiana echoslovakia Chemopetrol Chemlckezavody W. Piecka Finland Pekema Oy France AKZO Chomie EMC/DSM Daufac Rhone-Poulenc Solvic PCUK/Shell Chemie East Germany Industrie Anlagen Import West Germany Alusuisse Huls BASF Solvay Dynamit Nobel Hoechst Knapsack, AG Wacker ICI Greece Ethyl Hallas Holland AKZO Hoechst Shell? Hungary Chemokomplex Bososodi Vegyi Kombinat India CAP India National Organic Chemistry Iran Abadan Petrochemical Iran-Japan J.v. <s a srael Electrochemical Industries Location Baton Rouge, Louisiana Lake Charles. Louisiana Oyster Creek, Texas Plaquemme, Louisiana Baton Rouge, Louisiana Calvert City, Kentucky Lake Charles, Louisiana Lake Charles, Louisiana Guayanilla. Puerto Rico Daer Park, Texas Narco, Louisiana long Beach, California Geismar. Louisiana Plaquemine. Louisiana Deer Park,Taxas Skikda Bahia Bianca Capitan, Bermudez Bahia Bianca Botorry Anvers Feluy Tessenderlo Jemeppe-Sur Elclor Bahia Blanca Camacari Burgas Devnya Fort Saskatchewan Varennas, Quebec Shawinigan, Quebec Concepcion Peking Neratorice Novaky, Slovakia Porvoo Le Havre Jarrie Lavera St. Auban St Fons Tavaux FosSurMor Schkopau Marl Ludwigshaven Rhainberg Lulsdorf Gendorl Knapsack Knapsack Knapsack Burghausen Burghausan Wilhelmshaven Thossalonika Botlek Vlissingen' Berente Borenta Ka2incb>rcika Madras Bombay Abadan Bandar Basra Haifa Akko Process E/A/B E/A/B E/A/O E/A/O A/-/ E/O/B E/O/B E/O/B E/A/B/ E/A/B E/A/B E/A/B E/O/B E/A/B E/O/B E/A/B A/-/D E/A/B E/A/B E/A/B E/A/B E/A/B E/O/B E/A/B A/A/O Startup Year** 1968 1968 1969 1978 1964 I960 (1980) 1971 197Z 1972 1957 (1980) 1978 (1979) 1967 1972 1976 1968 1972 (i979) (1979) (i979) 1967 1969 Licensor BFG Stauffer Dow Dow Ethyl Ethyl BFG PPG PPG PPG Stauffer Stauffer Stauffer Stauffer PPG Stauffer, BFG, Mitsui Toatsu Dow ICI BFG ICI Stauffer BFG Hoechst, BFG Hoechst, BFG Ethyl Solvay, ICI BFG BFG PPG Dow BFG BFG E/A/O E/A/B E/A/B M/-/D 1978 1973 1972 1972 1971 B. F. Goodrich Stauffer BFG, Hoechst Salvty Engineer/ Contractor R. M. Parsons Ford, Bacon & Davis R. M. Parsons Fluor R. M. Parsons R. M. Parsons C. F. Braun R. M. Parsons Brown and Root Lummus, Badger. Brown 8; Root Toyo Engineering Chemico Badger BASF Badger Badger Solvay McKee, CTIP Badger Badger/Promon Techmp/TPL Badger Fish Engineering F. Uhde R. M. Parsons, Voest, Alpine F. Uhde CTIP E/A/B M/-/D E/A/B E/A/B E/A/B AE/-/D AE/-/D E/A/B E/A/O E/A/O EA/A/O E/A/O E/A/B E/-/D E/A/B E/A/B E/A/B E/-/0 A/-/E/A/B E/A/B E/A/B i967 1970 1965 (i980) (1979) 1973 1966 1972 1963 i971 (1980) 1971 (1979) (1981) 1978 1967 1969 (1979) (1980) (1979) Stauffer, BFG. Hoechst Rhooe-Progil Rhone-Pronil Solvay, Ethyl BFG Hoechst Rhone-Progil Rhone-Progil Solvay Badger F. Uhde Huls Stauffer Solvay Stauffer. BFG BFG, Hoechst BFG, Hoechst BFG BFG Stauffer/Stauffer Wicker ICI Ethyl Stauffer/BFG Hoechst Solvay C. F. Braun Uhde Badger, Uhde Badger, Uhda Badger, Knapsack R. M. Parsons R M, Parsons Fluor Comprimo*Lurgi AKZO Engineering Hoechst BFG, Hoechst BFG, Hoechst BFG Shell, BASF BFG Toyo Soda Stauffer Monsanto Uhda Badger Badger Badger, Lummus Hitachi Lummus, Thyssen VCM Capacity, MM Lba/Yr* 300 700 200 700 1,150 300 150 1,050 300 400 (1,000) 500 840 700 175 330 (1,000) 1,000 (88) no 73 287 7 240 (1,100) 440 440 550 220 (286) (330) (330) 7 (660) 126 126 35 176 265 240 88 440 795 291 440 440 (440) (440) (660) 700-770 160-320 440 130 375 220 (440) 220 330 176 350 (680) 33 660 (330) (350) 79 350 350 33 45 130 (330) 145 29 (220) Hydrocarbon Processing March 1979 ` 83 VINYL CHLORIDE MONOMER R&S 104943 move HC1 and certain clorinated byproducts which otherwise would hinder fractionation or pyrolysis. The "clean" EDC is subjected to distillation steps in which water and other light components are removed, as well as heavy components typically labeled tars. The dry product EDC, generally of 99.5 percent or greater purity, is thermally cracked to yield HC1 and VCM in an EDC carrier stream. Further distillation equipment separates EDC and HC1 for recycle and yields product VCM for final treating. The typical VCM plant includes VCM treating, offgas treating, light ends/tars handling and waste treating facili ties. It will also include incineration units for reclaiming waste chlorinated hydrocarbons from offgas or liquid streams.1 Stauffer technology.00'01 In the Stauffer direct chlori nation process (see Fig. 5), ethylene and chlorine are reacted, in the liquid phase and under controlled condi tions, to yield a crude product which analyzes 99.7 per cent EDC. The reactor product is then combined with the crude oxy EDC, washed and distilled to remove water, light ends and heavy ends. Pure EDC is preheated in the economizer of the pyrolysis furnace and then vaporized with steam. EDC vapor is then heated to dissociation temperature in the furnace tubes to yield a mixture of vinyl chloride and hydrogen chloride. Conditions are controlled to maintain EDC conversion at 50 to 55 percent. Following a quench and condensation step, HC1, VCM, and uncracked EDC are separated by distillation. Hydrogen chloride gas is sent to the oxy section. Unreacted EDC is recycled to purification. The oxy section combines recycle HC1 with fresh ethyl ene and air in tubular fixed-bed catalytic reactors. The ethylene and air are fed in excess of stoichiometric re quirements to assure high HC1 conversion.01 Reaction heat is removed by generation of steam on the shell side of each reactor. The final reactor effluent is cooled to condense EDC, and the offgas is contacted/reacted with chlorine to recover ethylene as additional EDC. The offgas stream is cooled versus cooling water and refrig eration to further condense EDC before exiting the pro cess. Residual ethylene concentration in the vent gas is reportedly as low as 10 ppm.1 . Stauffer also offers an oxygen-based oxy process (|b 6) in which the main reactor offgas, following conden^J tion of EDC, is compressed and recycled to the first oxy reactor. An excess of ethylene is used to maximize HC1 conversion and minimize byproducts. A small slipstream from the ethylene-rich recycle is purged to an ethylene recovery unit for control of inerts. Ethyl integrated VCM process.02 Gaseous chlorine and ethylene are introduced into a direct chlorination reactor in which they combine to form EDC. The very high purity EDC product can be sent directly to (or, after degassing, can bypass) the EDC purification system (see Fig. 7). Air and gaseous ethylene and HC1 are introduced into an oxychlorination reactor in which EDC is produced at an elevated pressure and temperature in the presence of a fluidized catalyst. The reaction products are neutralized and partially condensed to recover EDC which is first sent to a drying column and then to the EDC purification system. A portion of the vent gas, consisting primarily of nitrogen and carbon dioxide is recycled to the reactor for added safety. The purified EDC stream which contains recycled EDC as well as the EDC from direct and oxychlorina tion is vaporized and introduced into a furnace. At lear half of the EDC stream is cracked to HC1 and VCH The reaction products are cooled rapidly, partially coff densed, and then sent to the VCM purification system. 84 March 1979 Hydrocarbon Processing HC1 and VCM are separated by fractional distillation r 'fom the unconverted EDC and small amounts of by- roducts. The EDC, containing the byproducts, is re cycled to the EDC purification system. Mitsui Toatsu Chemicals technology.** The MTC technology utilizes a boiling liquid process for the direct chlorination reaction. Reaction heat is dissipated with the gaseous EDC exit stream which is condensed externally and sent to purification. The oxychlorination process is characterized by the use of oxygen feedstock and a fluidized bed reactor. The reactor effluent gases are quench cooled with circulating EDC followed by caustic neutralization. The neutralized gas is cooled to condense EDC and water. Uncondensed gases, primarily ethylene, are recycled back to the oxy reactor. A small stream is vented from the recycle gas to allow purging of inerts. EDC liquid is phase separated from water and dehydrated before joining the EDC streams in the purification system. A conventional EDC purification system splits crude EDC into light ends, heavy residue and pure EDC. The latter is cracked to yield VCM which is purified in a manner similar to that described in the Stauffer tech nology (see Fig. 8). PPG technology.09 The EDC production technology ppears very similar to that described for Mitsui Toatsu, particularly in the use of oxygen feedstock and fluidized bed reaction for oxychlorination. However, PPG does not indicate use of a dehydrator to dry crude oxy EDC prior to purification. Also, PPG uses three rather than two towers to obtain the HC1-VCM-EDC separation. B. F. Goodrich technology.07'T0 Goodrich direct chlori nation uses conventional water-cooled technology similar to that shown for Stauffer. The air-based, fluidized bed oxychlorination technology is similar to that shown for Ethyl. Goodrich also utilizes an absorber-stripper system on the oxy vent gas stream to minimize hydrocarbon losses. Goodrich, in conjunction with Badger, Inc., offers complete technology for waste treating of VCM plant effluent streams. Toyo Soda technology.58'07 This technology appears very similar to that offered by Stauffer. The principal differences are in the use of an absorber-stripper on the oxy vent gas effluent (as with Goodrich) and the de hydration of crude EDC prior to purification. As with other oxychlorination processes, steam generation is used to remove reaction heat. Phone-Poulenc technology os<71 Rhone-Poulenc offers two processes, Chloe I and Ghloe II. The former is of a special nature07 to yield concurrently significant quantities of other chlorinated hydrocarbons such as trichloroethyl ene and trichloroethane. The Chloe II process is "true" VCM technology using air-based, fluidized bed oxychlo rination in combination with boiling liquid direct chlo rination. Monsanto technology.72 This process appears very simi lar to that offered by Stauffer. Hydrocarbon Processing March 1979 85 VINYL CHLORIDE MONOMER ft R&S 104945 DOW technology. Dow's technology has not been pub licized. It has been used only by Dow and its foreign affiliates. NEW DEVELOPMENTS Although it is believed that several VCM producers currently use boiling liquid reactors for direct chlorina tion, Stauffer has developed a unique application of this concept.110 Their approach, "High Temperature Chlorina tion," in effect uses the reactor as a reboiler for the con ventional EDC purification system (see Fig. 9) Purified EDC is withdrawn as a side stream from the tower, and any light components formed are removed overhead. Normal feed to the tower consists of treated EDC from oxy and recycle. Small amounts of the normal heavy ends or tars are purged from the base of the reactor. This ap plication eliminates approximately 100,000 lbs. per hour of 150 psig steam consumption for a one billion lb. per year VCM plant. A similar energy savings is achieved in reduction of cooling water usage relative to a conven tional reactor and light ends tower. B. F. Goodrich73 also offers a boiling liquid process in which the heat of reaction is utilized to purify all EDC processed in the purification train. Increased activity by EPA (U.S. Environmental Pro tection Agency) and state agencies in regulating hydro- Fig. 9--Stauffer high temperature chlorination and ethylene dichioride purification schematic. 86 March 1979 Hydrocarbon Processing R&S 104946 carbon emissions are likely to stimulate further new de velopments, particularly in oxychlorination processes. These will range from development of new oxygen-based technology to various add-on systems for cleaning up oxy Cvent gas. The latter may include catalytic oxidation, inIneration (of oxygen-based oxy vent gas), solvent absorp tion, combined refrigeration and absorption techniques and/or other combinations. Several companies not active as VCM producers are involved in developing these add-on systems. It is expected that companies will continue to devote considerable effort to the development of cracking pro moters and inhibitors of side reactions in pyrolysis chem istry. Current cracking practices limit EDC conversion to 50-60 percent. Considerable energy and cost savings could be achieved through increased conversion levels without concurrent losses of EDC to undesirable side reactions. EPA regulations. EPA's "Standard Support and Envi ronmental Impact Statement: Emission Standard for Vinyl Chloride,"1 presented the following regulations: Emissions from all point sources except oxychlorina tion would be reduced to 10 ppm VCM by volume Emissions from the oxychlorination reactor would be reduced to 0.02 lb. VCM per 100 lbs. EDC product from the oxy process Preventable relief valve discharges would not be permitted f * Fugitive emissions would be minimized by requiring ^ enclosure of the emission sources and collection of the emissions. EPA estimated typical VCM plant emissions in 1974 as follows: Lbs./VCM/ Source 100 Lbs. VCM Fugitive 0.1215 EDC Finishing Column 0.05 VCM Finishing Column 0.24 Oxy Process 0.0364 Process Water 0.0007 Total 0.4479 The regulations were predicated upon reduction of such emissions by 94 percent using best available technology. Compliance testing of these installations was begun in the last quarter of 1978. Additional EPA and state actions were initiated in mid-1977 to reduce hydrocarbon emissions from VCM plants in non-attainment regions, i.e., much of the Gulf Coast. EDC production is reported to account for 28 percent of the hydrocarbon emissions in the southern Louisiana and East Texas AQCRs.8 These actions were lirected primarily against oxychlorination vent gas from air-based units. The amount of hydrocarbon reduction sought varies from region to region. No published guide lines are currently available to reference. The net effect of these various regulations has been to increase substantially the scope of add-on technology in VCM plants, such as: Installation of primary and redundant incineration facilities for VCM point (ex oxy) source and collected fugitive emissions Installation of HC1 scrubbing and neutralization or recovery units in conjunction with the incinerators Installation of closed process sewers, collection sys tems and larger or redundant waste water strippers Replacement of single mechanical seals on pumps and agitators with double mechanical seals. (In some cases, conventional pumps were replaced with canned or magnetic drive pumps) Leak detection systems and portable monitors Enclosed sampling and analytical systems Vapor recovery systems for VCM loading/unloading and equipment clearing. The EPA report estimated a maximum capital impacl of $0.8 to $1.9 MM (1975 dollars) for a "model" 70C MM lb. per year VCM plant. Recent cost estimates in dicate the true impact for these items is nearer $15 MM based on 1978 dollars. Addition of hydrocarbon compli ance (proposed regulations) may add another $2-$5 MM. EPA also has proposed further reductions in VCM emissions.5 Under consideration at present are regulations which will reduce allowable emissions from 10 ppm to 5 ppm for all point sources, including oxy vent gas. EPA further plans to prohibit emission increases within 8 kilometers of an existing source due to construction of a new emission source. This will effectively prevent expan sion of existing facilities or construction of new plants in the vicinity of existing plants. The proposed oxy vent gas regulation will also dictate substantial capital expendi tures for add-on facilities and possibly the conversion of air-based to oxygen-based plants to facilitate incineration of tail gases. ECONOMICS Table 5 presents a 1981 manufacturing cost buildup for a typical 700 MM lb. per year grass roots VCM plant. Raw materials total 12 cents per lb. VCM or 54 percent of the required FOB plant selling price. Capital-, related costs amount to 6.8 cents per lb. VCM or 32 percent. Utilities are only 6.7 percent of the total VCM cost. In perspective, the 1972-1973 reported VCM selling price1 was only 4-5 cents per lb. By 1981, the capitalrelated unit costs alone will exceed this by 50 percent. The obvious major factor in VCM pricing is raw ma terials cost. Although chlorine price is expected to double between 1973 and 1981, the impact of ethylene price will be even greater (three cents per lb. versus 17 cents per lb.). The real culprit, of course, is crude oil cost. During the late 1960s and early 1970s, plants using inexpensive LNG feedstocks were significant contributors to the low cost U.S. ethylene supply picture. The energy crisis rap idly reversed the low cost feedstock trend. LNG scarcity Hydrocarbon Processing March 1979 87 4* VINYL CHLORIDE MONOMER dictated construction of naphtha and/or gas oil crackers for present and future ethylene production. This tied VCM prices irreversibly to crude oil prices through ethylene, fuel and power (particularly via its impact on chlorine). TABLE 5--Estimated 1981 VCM manufacturing cost , 4 Raw Materials Chlorine............................. Catalyst and chemicals............... ............... Utilities.......................................................... Lb/Lb VCM 0.64 0.49 l/Unit 5.6 17.1 Celt, nar 3.53 8.45 0.39 1.42 X wa! ACKNOWLEDGMENTS The authors gratefully acknowledge contributions by A. B. Stryker, Jr,, of Stauffer and H. H. Wall of Ethyl and permission by their companies Labor......................................... . Miscellaneous................................................ 13.79 1.18 0.98 63.3 5.4 4.5 to use the information presented on tneir respective processes. Total fixed.............................................. Total manufacturing cost....................... 2.16 15.95 9.9 73.2 5.85 26.8 LITERATURE CITED 1 U.$, Environmental Protection Agency Report No. EPA-450/2-75-009, Selling price FOB plant................................ 21.79 100.0 Research Triangle Park, N.C., (1975). y-*3 * Leach, H. S. (to Monsanto Chemical Co.) U.S. Patent 3,338,982 (1967), >B.. F. Goodrich Co., British Patent 1,233,238 (1971). Campbell, R. G., (to Stauffer Chemical Co.), U.S. Patent 4,000,205 (1976). Benedict, D., (to Union Carbide), U.S. Patent 2,929,852 (1960). Di Fiore, L., and Calcagno, B., (to Soc. Ital. Resine), U.S. Patent 3,911,036 (1975). T Ttao, U., (to Lummus Co.), U.S. Patent 3,917,727 (1975). B*i*i: 1.700 MM Poundi/Year Balanced VCM Plant. 2.1981 Startup 3. Grass Roots Investment = 3140 MM. 4. Light and heavy ends incinerated; recovered HCi sold as muriatic acid to break even on incineration costs. 5. Fifteen percent DCF rata of return to cover interest charges and profit. 6. Unit values sro generalized and are not specific to a particular lisensor or technology. I Kurtz, B. D-, and Omelian, A., (to Allied Chemical Co.), U.S. Patent 3,941,568 (1976). Vulcan Materials, British Patent 980,983 (1965). 10 Van Antwerp, A. ., Harpring, J. W., Sterbenz, R. G., and Kang, T. L., (to B. F. Goodrich), U.S. Patent 3,488,398 (1970). II Severino, F T., (to Stauffer Chemical Co.) U.S. Patent 4,046.822 (1977). 11 Stauffer Chemical Co., British Patent 1,230,607 (1971). 11 B. F. Goodrich Co., Belgium Patent 680,413 (1966). :: Smalley, E. W Kurts, B. E., and Bandyopadhyay, B., (to Allied Chem ical Corn.), U.S. Patent 4,060,460 (1977). 3 Knapiaclc Co., British Patent 1,266,676 (1972). 3 Solvay et eie, French Patent 1,602,522 (1971). "Krekeler, A., (to Knapsack Co.), U.S. Patent 3,484,493 (1969). 3 jacklin, A. G-, (to ICI), British Patent 956,618 (1964). 'HKita, H., (to Mitsui Toatsu Chemical), Japanese Patent 46-43367 (1971). u Miyauchi, K., (to Mitsui Toatsu Chemical), British Patent 1, 189,815 u Takahashi, T., (to Mitsu* Toatsu Chemical), Japanese Patent 45-32406 (1970). Mitsui Toatsu Chemical, Japanese Patent 46-33010 (1971). "PPG Industries, French Patent 2,080,666 (1971). " Muen, A. P., (to PPG Industries), British Patent 1,220,394 (1971). M Ahlstrom, Jr., R. C., (to Dow Chemical Co.), U.S. Patent 3,966,30(1 (1976). 3 Froelich, W., (to Hoeehit), German Patent 2,217,694 (1973). "Barton, D. H. R., J. Chem. Soc., 148 (1949). "Young, D. P,, (to B. P. Chemicals, Ltd.), U.S. Patent 3,896,182 (1975). "Mitsui Chemical Industries, Japanese Patent 42-22921 (1967). 11 B. F. Goodrich, British Patent 938,824 (1963). "Knapsack Co., fr.S. Patent 3,476,955 (1969). **Monsanto Chemical Co., British Patent 1,168,329 (1969). M Keating, H. J., (to Monsanto Chemical Co.), U.S. Patent 3,125,607 (1964). "Gause, E. M., (to Monsanto Chemical Co.), U.S. Patent 3,142,709 (1964J. McDonald, D. W., (to Monsanto Chemical Co.), U.S. Patent 3,125,608 n5trini, J. C., and Costes, J. R., (to Rhone-Progil), U.S. Patent 3,935,286 ' Gomi, S., Eighth World Petroleum Congress, Proceedings 4, 371 (1971). 1 Kureha Chemical Industries, British Patent 977,578 (1964), British Patent 1,068,793 (1967). * Barton, D. H., and Mugdan, M., 7. Soc Chtm, lud, (London), 69, 75 About the authors Robert W. McPherson is products (1950); Patat, F., and Weidlich, 'Gordon, R. D., and Starks, C. P., M., Hclu. Chim. Acta., 32, 783 (to Continental Oil Co.), U(1.S9.4'P' ate/^ 4,046,823 (19775. m1 Kuck, M. A., (to Stauffer Chemical Co.), U.S. Patent 3,987,118 (t "Winstcin, N. J., (to Princeton Chemical Research, Inc.), U.S. ^ 3,551,506 (19701. manager, Continental Oil Co., Houston. He is responsible for the worldwide 1 Kurtz, B. E-, Smalley, E. W., Sommerman, W. ., and Van Atta, J. R., (to Allied Chemical Corp.), U.S. Patent 3,987,119 (1976). Gordon, T. H., and Kumraerle, H. F., (to Owens-Illinois, Inc.), U.S. profit performance of Conoco's chlo rinated hydrocarbons and their strategic Patent 4,042,639 (1972). Riegel, H., (to Lummus Co.), U.S. Patent 3,796,641 (1974). Riegel, H., (to Lummus Co.], U.S. Patent 3,557,229 (1971). development. Mr. McPherson received his B.S. from Cornell University. 'Riegel, H., (to Lummus Co.], U.S. Patent 3,937,744 (1976). Sze, M. C-, (to Lummus Co.), U.S. Patent 3,949,010 (1976). 1 Tsao, U., (to Lummus Co.), U.S. Patent 3,963,584 (1976). 1 Tsao, U-, (to Lummus Co.], U.S. Patent 3,992,460 (1976). Riegel, H., (to Lummus Co.), U.S. Patent 3,935,288 (1976). "Tsao, U., (to Lummus Co.), U.S. Patent 3,985,816 (1976). ** Minot, J. D., Chem. Eng, Progr,, 69, (8), 71 (1973). Charles M. Starks is director of ex Leonard, E. D., Vinyl and Diene Monomers (Part 3). John Wiley and Sons, Inc., New York, 1971. " Sittig, M., Vinyl Chloride and PVC Manufacture, Noyes Data Corp., 1978. ploratory research. Continental Oil Co., Ponca City, Okla. Dr. Starks received his BJi. from the University of Okla " Gomi, S., `'Japan's New Vinyl Chloride Process (Kureha)/' Hydrocarbon Processing, Vol. 43, No. 11, November 1964. T Roienzweig, M. D., /'Vinyl Process Has Wide Range of By-Products," (Rhone-Progil), Chemical Engineering, Vol 78, No. 24, Oct. 18, 1971. R&S 104947 homa and his PhD. from Massachusetts Institute of Technology. " Robert, J., and Bergier, A., "Rhone-Progil New Processes for the Manu facture of Vinyl Chloride Monomer and Chlorinated Solvents from Ethyl ene," 164th A.C.S. National Meeting, New York, Aug. 27-Sept. 1, 1972. M Buckley. J. A., "Process Flow Sheet/Vinyl Chloride via Direct Chlorina tion and Oxychlorination," Chemical Engineering, Vol. 73, No. 24. Nov. 21. 1966. * Private Communication from A. B. Stryker, Jr., Stauffer Chemical Co.. Nov. 29, 1978. ** Reich, Peter, "Air or Oxygen for VCM?" Hyydrocarbon Processing, March, 1976, pp. 85-89. " Private Communication from H. H. Wall, Ethyl Corp., Nov. 28, 1978. * Vinyl Chloride, "Hydrocarbon Processing, Nov.? 1975. Garvin J. Fryar is supervising process engineer with Continental Oil Co., EPA-450/3-73-006-C, Vol. 3, November, 1974. ** Federal Register, June 2, 1977. EPA-600/2-76-053, March, 1976. Ponca City, Okla. He is responsible for the supervision of process designs, " Keane, David P., et a!, "Vinyl Chloride: How, Where, Who--Future," Hydrocarbon Processing, February, 1973. "Vinyl Chloride--Mitsui Toatsu Chemicals," Hydrocarbon Processing, No technical consulting and economics for chemicals processes. Mr. Fryar received vember 1971. " "Vinyl Chloride--PPG Industries, Inc.," Hydrocarbon Processing, Novem ber 1975. his BJS. in chemical engineering from the University of New Mexico. T* "Vinyl Chloride--B. F, Goodrich Chemical Co., Hydrocarbon Proceessssing November 1975. 11 "Vinyl Chloride--Rhome-Poulenc S.A.," Hydrocarbon Processing, Nib ber 1975. " "Vinyl Chloride--(Monsanto Co.)," Hydrocarbon Processing, Novel 1975. " Private communications from J. S. Benson B. F. Goodrich Chemical Co.. Jan. 5, 1979. 88 March 1979 Hydrocarbon Processing