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Khartoum Petrochemical Co.,Ltd. :: First Petrochemical Company in Sudan :: First Petrochemical Company in Sudan :: First Petrochemical Company in Sudan :: First Petrochemical Company in Sudan

Petroleum and Gas in Sudan:

Sudan did not stop its endevoures to explore and exploit its petroleum deposit for half a century, under the colonial rule and during the national rule in its different phases in cooperation with some foreign petroleum companies.
The great burden of the importation of petroleum materials on the Sudanese balance of payment was one of the main reasons which made the encouragement of investment reaches its summit through the last ten years, as the government considered petroleum one of the basic pillars of its economic strategy and opened the door of the investment to a number of the international petroleum companies.
Exploration:
The actual exploration operations began after the signature of an agreement with the American chevron company in 1974.
According to the good results in the central Sudan another bilateral agreement with chevron was concluded in 1979.
After that other agreement were concluded with French total company and the American Sun oil company in 1980 – 1982.
After the conduction of geological and geophysical surveys in the different parts of the country 95 experimental wells were digged, 46 of them were productive such as the fields of sawakin, Abu jabra, sharif, the unity, talh, Hejelij, Adareel and kaigang, 49 wells are dry. But these explorations were not followed by and productive activity.
During the years 1989 – 1999 the Sudanese government concluded a number of agreements with different petroleum companies including the two Canadian companies IPC and SPC in 1991 – 1993, the gulf company 1995, the Chinese national petroleum company CNPC in 1995 and the consortium company in Feb. 1997.
The international company GNPOC was established in 1997.
As a result a number of the exploration companies carried their work in the different parts of the country.
The real production:
The petroleum production in Sudan began in Abu jabra and sharif fields, Adareel and Hejilij field followed. The total production of petroleum in Sudan up to 1998 was over three million barrels, That Abu Jabra and sharif produced 471629 barrels, Adareel 196347 barrels and Hejlij 2517705.
By the end of June 1999 the real production reached 150 thousand barrels from Hejelij and unity fields. The government expects new production from new fields in the areas assigned to the companies, which will increase the Sudanese oil storage.
The Sudanese oil qualities:
The Qualities of the Sudanese petroleum differ according to the fields, but its most important qualities can be summarized in the followings:
The crude Sudanese petroleum has a medium thickness similar to the light materials.
It is categorized as one of the materials that include paraffin wax, which is chemical component of oil, which is a good burning material, and of high productivity in complex refining circumstances. The …… of the paraffin materials are the qualities of pouring and transport.
The Sudanese crude oil is characterized by including a little quantity of sulfur, therefore its one of the best oils in the middle east because sulfur has harmful side effects on the environment and the engines.
The Sudanese petroleum is also characterized by having the specification of dezil derivative as the sixty’s number is high and that raises the burning competence.
The export pipeline:
The length of the pipe which begins from Hejilij to Alobied and Khartoum refineries to Bashair port on the Red sea south of port Sudan is 1610 km. the pipe line capacity in the first stage is 250000 BPD in the year 2000.
The project cost is about amiliar dollars and it is executed by a number of specialized foreign companies, all of them worked under the supervision of the great Nile Company for petroleum operations GNPOC.
The line was established and opened on 31, may 1999 and it works successfully. The Khartoum Oil refinery The Khartoum oil refinery is located in north of Khartoum 70 km away by the eastern side of the Tahadi road – Atbara – Alkhartoum it is 12.5 km away from the Nile. The pipe line of the crude oil export runs to the west of it about 500 meters away the refinery area is half square km, an area of 8 skm has been reserved for the refinery and its extensions, a similar area is reserved for the marketing companies and the projects connected to the refinery.
The share holding companies The refinery is a share holding enterprise between the government of Sudan represented by the Ministry of Energy and Mining – Sudapet company – and the Chinese National Petrolum Company GNAC, that each of the two partners own 50%, contracted for some period of time with accost of 640 million dollars.
The design capacity and the main units of the refinery The refinery was designed for 50000BPD equal to 2.5 million tons annually.
It is composed of 5 main units:
The air. Unit.
Penzin improvement unit.
Dezil processing unit.
Breaking unit.
Acids removal unit.
There are also other assisting units such as the cermal station.
The refinery covers the domestic demand The refinery covers 20% of the fuel requirements, provides the National Electricity network with 20 megawatt and covers 90% of the country’s gas oil requirements, The penzin production is fire folds more than the country’s need, also the gas production is more than the country’s requirement that it can covers this need up to 2002.
The refinery will export 500 thounds tones of benzine with high octeen annually, as for the gas surplus some of it will be used in the generation of electricity while the rest will be exported.
Some of the refinery qualities:
The Khartoum refinery is specially designed for the Sudanese crude oil, it is a number of a complex refinery, which is suitable for the introduction of petrochemical industries in the future.

North Africa's Ptroleum Potential:

By Sharon P. Stultz-Karim Examination of North Africa’s petroleum potential indicates that countries can be classified in two categories; as mature producers and as under-explored nations.
1. Mature Producers
a. Algeria
Algeria's mature fields indicate that substantial infrastructure, expertise, and regulatory policy is in place; however, the mature fields also indicate declining production. Much investment in enhanced oil recovery (EOR) technology as well as exploration is needed to replace reserves and to maintain a high production/reserves ratio. Sonatrach, the state-owned oil and gas company, has initiated an ambitious program to transform itself into a transnational company. In addition, the government continues its efforts to contain political instability through a domestic insurgency movement which has effected foreign investments.
b. Egypt
Egypt's mature fields are reflected in declining production. Again, investments in EOR as well as exploration to maintain production/reserves levels are needed. Recent natural gas discoveries are encouraging and are likely to be used primarily for export since present production is used for domestic demand. Any additional oil discoveries are likely to be targeted for export also. Political violence through internal terrorism has given cause for a perception of risk for international investments but the government's counter measures have been effective in diminishing that perception of risk.
c. Libya
The international economic sanctions placed against Libya has been the nation's biggest obstacle to reversing its mature fields' declining production. Again, large investments are required to for EOR projects and exploration.
Under-Explored Nations a. Morocco
Morocco has modest proven reserves and production. Government plans for expanding gas production will be for domestic demand rather than export.
b. Sudan
Sudan's petroleum potential has not been fully explored primarily because of the ongoing civil war which started in 1983. Some exploration activity has begun which the country needs desperately to ease war related hyperinflation and budget deficits. Large scale exploration and production projects will not go on until the civil war is settled.
c. Tunisia
Although proven reserves are relatively modest, Tunisia' s exploration potential is bright.
The country is underexplored and is enjoying keen international interest.
II. ALGERIA
Background Algeria continued to experience political and economic uncertainty in 1998.
Despite the violence and political conflicts, Algeria's economy continues to move in a positive direction.
President Zeroual has successfully resumed the IMF-approved macroeconomic stabilization program,which began in 1989. In addition, Algeria's state-owned oil and gas company Sonatrach has initiated a $28 billion investment program designed to transform it into a transnational company with both upstream and downstream ventures overseas and to further develop Algeria's oil and gas resources in conjunction with foreign partners.
Algeria has continued to attract foreign investments for its oil and gas industries despite the perception of risk due to reccurring violence.
Oil and natural gas export earnings comprise about 95 per cent of the country's total export revenues.
Government plans are to diversify the export base and increase non-hydrocarbon exports from just over $500 million in 1996 to $2 billion annually by 2000. Unemployment at an estimated 30 per cent in 1997, nevertheless, continues to be a problem.

PetroChina —— Stock Information:

From May.26.2004,we start to supply woven sacks to WFP(World Food Program).
The total amount will be up to 1200,000 pcs 2004-05-26

PetroChina —— Stock Information:

On Junr.10.2004, donation 5000 pcs woven sacks and 100 pcs woven proof cloth to Darfour people on behalf of MEM and CNPC.

PetroChina —— Health Satefy and Environment:

It is the consistent standpoint of PetroChina Company Ltd. that the most important resources of the world are human beings and the natural environment they rely on for their existence.
The Company has all along regarded it as one of its most important tasks to safeguard its staff's health, take precautions against accidents and protect the environment.
For these reasons the following measures have been taken:
Policies, regulations and standards have been mapped out with regard to health, safety and environment so as to implement allotted responsibilities in these connections;
Health, safety and environment are regarded as major management factors to be included in all production and business activities of the Company;
It is stipulated that targets set for HSE are key business indicators to check on the staff, so that all its members have a clear sense of responsibility as to health, safety and environment.
In order to carry out effective HSE management and coordinate them with production and business operations, the Company has been forming and implementing an integrated HSE mamagement system based on experience accumulated through years' practice in the related areas that has already taken the form of regulations and standards.
The implementation of the above system at various management levels, work fields and contractors can provide different areas and sectors with the required standards and procedures, upon which each member of the staff can do his job within his prescribed duty; put forward any possible improvement; check, evaluate, and report what has been done in health, safety and environment; and make a point of continuously raising the management level in these three respects.


Comment On Petroleum Prices:

Candidates Must Address Energy Debate This article is a reprint of a guest column that appeared in the Wisconsin State Journal - June 5, 2000 by Michael Vickerman Of all the issues that George W. Bush and Al Gore would rather not debate during this presidential contest, none ranks higher than energy supply.
Both candidates understandably regard energy politics--more specifically, petroleum prices--as electoral quicksand that can sink a presidential contender faster than you can say Jimmy Carter.
Gore and Bush fervently hope that the recent run-up in energy prices will not affect the political landscape until after November 7, but this is whistling past the graveyard.
Higher oil and natural gas prices are here to stay, a product of escalating demand and flattening extraction rates.
But for obvious reasons going back to 1980, both major party candidates are loath to tell the public that global oil production will peak sometime this decade, and that motorists will never again see gasoline priced as cheaply as it was in 1998-1999.
So why are energy prices rebounding so sharply 15 months after plummeting to the lowest levels in modern history?
Actually, the most recent price slump is partially responsible. When prices sink below production costs as they did in 1998-1999, oil suppliers invariably scale back throughput and exploration activity.
As this occurs, global demand picks up, fanned in part by rock-bottom prices.
Without the revenues needed to invest in additional capacity, however, oil suppliers are wont to sit on their hands and let the global economy burn through the excess inventory.
The trouble is, while global consumption climbed from 73 to 77 million barrels of oil per day since 1996, production capacity barely registered an increase during that time.
According to published reports from the Middle East, global production this year will fall short of current demand.
Moreover, the measures needed to lift production levels to 80 million barrels per day, including replacement of aging infrastructure in Iran and Iraq, cannot be economically justified unless petroleum prices continue to climb.
And they will, no matter how many oil ministers Energy Secretary Bill Richardson visits between now and November. Even if the OPEC nations decided tomorrow to expand global extraction capacity by another 5%, which would necessitate up to $100 billion in investment capital, output from the Middle East wouldn't start rising until 2003 at the earliest.
Don't expect any relief from non-OPEC nations like Mexico, Norway, and the U.K, even though their domestic economies are no less insulated from the inflationary effects of higher oil prices than ours. All three countries are at their production peaks, with nowhere to go but downhill.
As for the U.S., whose output as late as 1950 equaled domestic consumption, oil production has declined by 30% since peaking in 1970, and now accounts for barely 40% of the nation's current intake.
If production can't keep up with current consumption levels, then prices will go up until demand falls in line with supplies.
Only once in U.S. history did demand for petroleum products decline.
It happened over a five-year period from 1978 to 1983, when oil prices shot up from $12 to $33 per barrel.
Conservation measures took hold during that time, though less a result of enlightened policy than economic necessity.
Ironically, it was only when prices sagged to $12 per barrel early last year that daily consumption broke through the previous record set shortly before the 1979 oil embargo.
We've just about come full circle since those tumultuous times. The long reprieve from oil-induced economic disruption is rapidly coming to a close.
It's early yet in the cycle; even at $1.50 a gallon, the price of gasoline is lower in real terms than in 1985. So how is the federal government addressing this developing problem? By issuing forecasts of lower gasoline prices this summer, in the face of all evidence to the contrary.
This sort of denial is to be expected as long as energy policy is regarded as the third rail of American politics.
But an informed debate on this issue, encompassing a wide range of options to reduce demand for petroleum, is exactly what is needed before the November election.
That debate cannot start until Bush and Gore pull their respective heads out of the sand and acknowledge the voters' growing unease over fuel prices, and propose some realistic remedies.

PetroChina —— Stock Information:

The shareholders' general meeting is the organ of authority of the company, which exercises its powers in accordance with the Company Law.
The shareholders' general meeting exercises the following powers: to decide on the company's operational policies and investment plans; to elect and replace directors and decide on matters relating to the remuneration of directors; to elect and replace the supervisors who represent the shareholders and to decide on matters relating to the remuneration of supervisors; to examine and approve the board of directors' reports; to examine and approve the supervisory committee's reports; to examine and approve the company's proposed annual preliminary and final financial budgets; to examine and approve the company's profit distribution plans and for loss recovery of plans; to decide on the increase or reduction of the company's registered capital; to decide on the issue of debentures by the company; to decide on matters such as merger, division, dissolution and liquidation of the company and other matters; and to amend the company's articles of association.
Resolutions of shareholders' general meetings shall be divided into ordinary resolutions and special resolutions. An ordinary resolution must be passed by votes representing more than one-half of the voting rights represented by the shareholders (including proxies) present at the meeting.
A special resolution must be passed by votes representing more than two-thirds of the voting rights represented by the shareholders (including proxies) present at the meeting.
Shareholders' general meetings can be annual general meetings or extraordinary general meetings. Shareholders' meetings shall be convened by the Board.
The Board shall convene an extraordinary general meeting within two months of the occurrence of any one of the following circumstances: where the number of Directors is less than the number stipulated in the Company Law or two-thirds of the number specified in the Articles of Association; where the unrecovered losses of the Company amount to one-third of the total amount of its share capital; where shareholder(s) holding 10 per cent. or more of the Company's issued and outstanding shares carrying voting rights request(s) in writing for the convening of an extraordinary general meeting; whenever the Board deems necessary or the supervisory committee so requests.
When the Company convenes a shareholders' general meeting, written notice of the meeting shall be given not less than 45 days before the date of the meeting to notify all of the shareholders whose names appear in the share register of the matters to be considered and the date and the place of the meeting, provided that in the case of holders of Domestic Shares, notice may also be given by way of public notice issued 45 to 50 days prior to the meeting. The Articles which require a written reply to be delivered within 20 days shall not apply. A shareholder who intends to attend the meeting shall deliver to the Company his written reply concerning the attendance at such meeting to the Company 20 days before the date of the meeting.
When the Company convenes a shareholders' annual general meeting, shareholder(s) holding 5 per cent. or more of the total voting shares of the Company shall have the right to propose new motions in writing, and the Company shall place such proposed motions on the agenda for such annual general meeting if they are matters falling within the functions and powers of shareholders in general meetings.
An extraordinary shareholders' meeting shall not decide on matters not stated in the notice of meeting.
The Company shall, based on the written notice which it replies receives 20 days before the date of the shareholders' general meeting from the shareholders, calculate the number of voting shares represented by the shareholders who intend to attend the meeting.
If the number of voting shares represented by the shareholders who intend to attend the meeting amount to more than one-half of the Company's total voting shares, the Company may hold the meeting; if not, then the Company shall within five days notify the shareholders again by way of public announcement the matters to be considered at, the place and date for, the meeting.
The Company may then hold the meeting after such announcement.
A notice of meeting of the shareholders of the Company shall satisfy the following criterion: be in writing; specify the place, date and the time of the meeting; state the matters to be discussed at the meeting; provide such information and explanation as are necessary for the shareholders to make an informed decision on the proposals put before them. Without limiting the generality of the foregoing, where a proposal is made to amalgamate the Company with another, to repurchase the shares of the Company, to reorganise its share capital, or to restructure the Company in any other way, the terms of the proposed transaction must be provided in detail together with copies of the proposed agreement, if any, and the cause and effect of such proposal must be properly explained; contain a disclosure of the nature and extent, if any, of the material interests of any Director, Supervisor, president, vice president or other senior officer in the proposed transaction and the effect which the proposed transaction will have on them in their capacity as shareholders in so far as it is different from the effect on the interests of the shareholders of the same class; contain the full text of any special resolution to be proposed at the meeting; contain a conspicuous statement that a shareholder entitled to attend and vote at such meeting is entitled to appoint one or more proxies to attend and vote at such meeting on his behalf and that a proxy need not be a shareholder; specify the time and place for lodging proxy forms for the relevant meeting. Notice of shareholders' general meeting shall be served on each shareholder (whether or not such shareholder is entitled to vote at the meeting), by personal delivery or prepaid airmail to the address of the shareholder as shown in the register of shareholders. For the holders of Domestic-Invested Shares, notice of the meetings may also be issued by way of public announcement.
The public announcement referred to in the preceding paragraph shall be published in one or more national newspapers designated by the State Council Securities Policy Commission within the interval between 45 days and 50 days before the date of the meeting; after the publication of such announcement, the holders of Domestic-Invested Shares shall be deemed to have received the notice of the relevant shareholders' general meeting. Such public announcement shall be published in Chinese and English in accordance with the Articles of Association.
The following matters shall be resolved by way of ordinary resolution of the shareholders' general meeting: work reports of the Board and the supervisory committee; profit distribution plans and loss recovery plans formulated by the Board of Directors; removal of the members of the Board and members of the supervisory committee, their remuneration and manner of payment; annual preliminary and final budgets, balance sheets and profit and loss accounts and other financial statements of the Company; matters other than those which are required by the laws and administrative regulations or by the Articles of Association to be adopted by special resolution.
The following matters shall be resolved by way of special resolution of the shareholders' general meeting: increase or reduction in share capital and the issuance of shares of any class, warrants and other similar securities; issuance of debentures by the Company; division, merger, dissolution and liquidation of the Company; amendment of the Articles of Association; and any other matters considered by the shareholders in general meeting, resolved by way of an ordinary resolution, to be of a nature which may have a material impact on the Company and should be adopted by a special resolution.

Artical 1 Feed stocks for Petrochemical:


(A) Introduction:

Generally the feed stocks are classified on the bases of the existing from i.e. solid, liquid and gas. These are:
1. Gases: Associated gas (obtained with crude oil), Lean gas (Gas stripped of the condensable: mostly methane), Refinery of Gas (gases from crackers, cockers. stabilizers, and other unit.) Natural gas, LPG etc.
2. Light Liquids: Natural Gas Liquids, Naphtha, wild gasoline, Kerosene, gas oils Reformats, cockers fractions, FCC Lights etc.
3. Heavy Liquids: Vacuum gas oils, fuel oils, waxy distillates, heavy crude etc. 4. Solids: waxes, Deasphalter bottoms, bottoms of distillation columns and storage tanks, Residuum.
In fact there is no bar in using any hydrocarbon; however the economy, purification, availability of raw materials, in abundance and technology for the particular fraction are the only impediments. It is traditional to use some fractions for certain intermediates or products like naphtha for olefins or for synthesis gas or hydrogen. One can see the production of hydrogen through different process using different feeds, however the available raw material has to be utilized for pecuniary gains and conservation of the petroleum stocks. When the raw material is used for producing a chemical, the purification of the stock is foremost important and the purification is devised on the state and the shape of the feed stock. Each fraction or each destination requiring a special type of purification perhaps in addition to common purification procedures. The complications of purification and cost of purification usually increase with the molecular weight of the feed stock. Though a maximum purification is anticipated in gaseous feed stock, the cost may not be that much compared to the purification of heavy stocks, because the gas, either field of process, can be easily purified. Usually the field gases will be rich in saturates though the composition of each is different and the processed gases will be rich in saturates. Hence the purification procedure and the degree of purification varies from gas to gas.

(B) Purification of Gases:

All the above gases listed are used as feed stocks for petrochemicals. However if facilities for petrochemical industries are not available, then the gases of high heating value are diverted to industrial heating system or to domestic necessities. All the gases, irrespective of origin, contain some unwanted extraneous constituent named impurities.
Most common of the impurities are listed below:
1. Water vapor
2. Mechanical ( suspended) impurities
3. Chemical impurities
4. Other than above mentioned impurities.

(C) Water steam:

This is exceptionally presents in all the fractions. Gases from atmospheric column or other refinery units, condensate gases and natural gas do have variable amounts of water steam this can be removed by passing through drying agents like silica gel, bauxite, dehydrated salts or even by absorbing with glycols.It is observed that some that some hydrocarbons have the capacity to form crystalline hydrates, such examples are: CH4 7H2O, C2H6 7H2O, etc. these gases exhibit the crystalline forms even above the freezing point of water. These hydrates not only clogg the delivery lines but facilitate other abnormalities like corrosion, malign catalyst, cause hydrolysis in chemical reactions. In modern literature, hundreds of dehydrating agents are mentioned, of late, the tendency of using polyhydric alcohols or glycols have been on increase. Liquid absorbents are not as efficient as solid desiccant for absorbing water vapor. Ethylene glycol is conventional used to remove the moisture from gasoline as well as gases. However, the amount of glycol required for circulation is very high, i.e. 20-40 times of vapor removed usually 35-40c drop in dew point is obtained with glycols. Addition of toluene to glycols help in reducing the water content to less than 1000 pp m and is used in DRIZO process 10. Solid desiccants, synthetic gels, calcium chloride can decrease the dew point even by 80 C.Presently, molecular sieve of type 4A, 5A have shown a commendable performance. They can lower the dew point even by 100 cent grate degrees. These sieves are vastly used in N.G. air liquefaction plants. Obviously drying by means of solid adsorbents is more economical and simple. When bentonite clays are used as adsorbents, regeneration may not be attempted. But, when synthetic adsorbents are used the regeneration is done simply by heating the bed to 200 cent grate degrees to 300. The moisture capacity of the clays is usually small - of the order 2.5 to 4%, while that of synthetic alumina gels is 5 to 8%. Similarly, synthetic alumina gels voraciously adsorb moisture up to 22%, when they are fresh, but due to fatigue in long duration of operation the capacity drops to 01%. Each adsorbent has its own moisture removal capacity and regeneration temperature. The best dehydrating agent, of course, is lithium chloride, but its use is curtailed due to its cost.

(D) Mechanical (Suspended) Impurities :

The sources for the mechanical impurities are many. Mining operations invariably bring clay, dust, etc. Catalytic cracker gases are abounding in catalyst dust. Process gases like coker, cracker gases, if not contain any solid particle likely to bring condensed droplets of tars. Relatively, Atmospheric Distillation Unit (ADU) and stabilizer gases are free from such impurities. Usually all types of mechanical impurities can be removed by washing with water. Suitable solvent is preferred if tar and heavy hydrocarbon oils are present, sometimes, the removal of suspended particles is resorted to be simple setting but it does consume a good deal of time.When a solvent wash is decided to eliminate chemical impurities naturally water washing may be skipped off. The washed solvent is filtered before recycling; this will ensure the continuous removal of suspended impurities too.

(E) Chemical Impurities:

Sulphur and its compounds are the foremost of the chemical impurities. Sulphur can exist right in gases from the liquid form. The elimination of sulphurous compounds will not only reduce the corrosion problem but indirectly helps quality of fractions too. Such cases are plenty; sulphur free gasoline requires less lead to boost the octane number. Further sulphur defies the activity of catalyst. In some reactions sulphur is very detrimental too. Sulphur exists in the form of hydrogen sulfide, mercaptans, thiophnes, sulphides, polysulphides etc. these impurities are present in all the gaseous fraction and light petroleum fraction (full range naphtha). Sulphides, polysulphides are present in high boiling stocks. Even natural gas that forms the feed for ammonia has to be desulphurised. This is carried out using activated carbon fortified by zinc oxide and other metallic additives. At the temperature of 400 cet grate decrees, these catalyst preparations are good for removal of H2S, mercaptans and small percentage of COS. Cat cracker or Coker gases invariably contain carbon dioxide to a small amount, i.e. 1000 ppm. Other impurities like ammonia, oxides of nitrogen mark their presence to an extend of a few ppm. Many processes are listed for the selective removal of these impurities. The most famous process of all these is ethanolamine (Girbotol). This employs a 20 to 30% aqueous solution of ethanol amine (mono, bi, tri). Ethanol amines being basic can absorb all the acidic gases freely as per the reactions cited:
All the absorption reactions are favored by low temperatures (25- 30 degrees cent grade), while temperatures above 100 degrees favor the desorption reactions. Other solvents based on amine compositions are diglycol amine (DGA), disopropylamine (DIPA), methyl diethanol amine (MDEA). Some new solvents are credited with taking very heavy loads i.e. about 2 to 3 cubic meters of gas can be absorbed per equal amount of circulation (mole to mole). Further sulphur (mercaptant) removal is up to 55% (C1 fractions). The recent innovations suggest methyl diethanol amine (MDEA) is a better solvent when high concentration of Co2 is present in the feed gas.
When concentration of acid gases exceeds 0.45 Mol/Mol amine solution; MEA, DEA, TEA are not suitable. The first plan in the world Domes North Caroline, Plan has been converted to MDEA solvent system and is found to operate convincingly at the higher efficiency. In fact, there are many processes which are currently under operation to scrub the off gases, a gist of which is presented in table 1.4. When a high amount of carbon dioxide (65%) and fairly a good amount of H2S are present, the mixture can be handed by Selexol process which uses dimethly ether of propylene glycol.
All the gas treating process may be classified into three classes depending upon the operational pressure.
a) Low pressure operation (Below 10 bars) Girbotol, Economizer, Flex sorb-PS Thiolex Selxol, Sulfolin.
b) Medium pressure (up to 100 bars). MDEA, Adip Benfield, Catacarb, Flexsorb- HP, Gaimarco- Vetrococke, Stratford, Sulfinol.
c) High pressure (above 100 bars) Rectisol, Selexol, Benifield.
When sulfur removal alone is to be judged, Amine/claus process is economical for large installations, because of the capital intensive nature. Such installations are good for recovering more than 25 tpd of sulfur.Locate iron-red ox process is suitable for recovering less than 1tpd of sulfur, however operating costs are much. Sulferox of DOW employs improved iron chealates that can work under higher concentrations without much dilution thus decreasing operating and equipment cost. Bender sweetening is generally useful for NGLs, gasolines; however LPG can also be processed.
These plans are considered to be cheap as the mercaptans are covered to disulfides only. Beavon sulfur recovery (BSR) MDEA process is a purification process for the tail gas from different units. The process works in two steps, initially all sulfur is covered to H2S by hydrogenation. In second stage H2S is absorbed by amine. Merox process is another new one; it can treat gases, LPG, light naphtha, and kerosenes. These extract mercaptans from gases and low volatiles, while heavy stocks respond to oxidizing mercaptans to disulfides.
ADIP Process uses Di isopropanol amine or tertiary mine, methyl diethylnol amine in 50% aqueous solution and is capable of handling gases of ppm sulfur 10 ppm sulfur in liquids COS is generally oxidized.Similarly Thiolex employing caustic solution extracts Hydrogen sulfide, carbon dioxide and mercaptans.Beavon-others process is peculiar in one respect it alters the composition of Claus tail gas and by first catalytic oxidation of all sulfur compounds over a CuO bed and then hydrogenated to convert the gases in to H2S or NH3. MDEA extracts sulfur compounds to separate clean gas from acid gas stream and selected separates clean gas from elemental sulfur. Modop is a process for removal of sulfur from tail gas to meet the population regulations. Tail gas is first heated with fresh air and fuel to oxidize all the components of sulfur and then hydrogenated to yield H2S which is later selectively oxidized to sulfur. Shell Claus off-gas treating (Scot) process also works on the same principle. Selexol is another process for recovering sulfur from H2S streams, while sulferex is suitable for removing SO2 from off gases. Stratford process is suitable for operation on H2S gas streams.
The operation is simple and illustrated in fig 1. 2a Mixture of gases enters at the bottom of absorber, through a gas distributor. The gas goes in to absorber and mixes freely with the down coming liquid, and the purified gas leaves the absorber at the top. The fat liquid is filtered and desorbed in a similar column by steam heating. When DEA solutions are used for gas treating plants filters are required to remove fine particles, which are trapped during contact with liquid. This is to remove foams and inimical deposits. This is however absent with MEA solution. Absorbed CO2, H2S are liberated by steam stripping. The solution is then made to the required concentration and cooled; after which it is fed into the absorber from the top. The absorption, desorption temperatures are kept around 25 degrees cent grade, 110 degrees cent grade respectively. To facilitate easy absorption, the absorber is superimposed with a pressure of 0.5 to 1.0 MPa. It may be thus mentioned the merits of a process is more or less connected with amount of impurities and nature of these. Beavon-other process is shown, the selector X separates sulfur from gas.
Membrane separators along with amine treatment have been tried for efficient and economic operations. Sulfur removal by adsorption or solvent absorption is followed in the same operations where CO2 or H2S removal is affected. Molecular sieves are also employed to desulferise certain stocks, especially gases.In most of the cases the solvents are regenerated by expelling the absorbed gases. Expect in certain cases, the regeneration is done by air-blowing (Merox) when solutions are employed removing impurities, the gases are again dried. Separation of gases into individual Constituents:
Gases ranging from C1- C4 are freely available either in cracked, ADU, or stabilizer streams. Further, permanent gases like air, N2, Co, Co2, and H2 are also present in varying extents. The separation of the gases into individual constituents is a costly process, but has to be.
Industrially the separation techniques consist of
1. Absorption - Desorption
2. Compression- Liquefaction
3. Low temperature fraction
4. Adsorption
5. Special techniques.

(F) Absorption - Desorption:

The gases are selectively absorbed in suitable solvents and then absorbed. The absorption is usually a physical process; however it may be even chemical absorption. The removal of SO2, CO2, NO, etc. is basically by chemical absorption. Hydrocarbon gases are mostly separated by physical absorption; propane, butane is highly soluble in light hydrocarbon oils, permitting the recovery up to 70-80%, with purity approaching 100%. Some gases like acetylene may be absorbed by solvents like dim ethyl form amide. Even aromatics can be separated by using tetra ethylene glycol. Almost all olefins and diolefins can be separated by selecting a suitable solvent. Ethylene, propylene, butane, butadiene may be separated by mono ethanol diamine solution of cuprous nitrate/ chloride, due to varied solubilities under different pressures. The ethanolamine and metal salt mixtures can absorb CO and acetylene in addition to olefins. Absorption is done at low temperature, while desorption is carried out at 50 degrees cent grade. Silver fluoroborate is found to be better than a mine, as it is not affected by the presence of acetylene -carbon monoxide mixtures. Ag BF4. 2C2 H4 is formed during absorption which easily decomposes.

(G) Low temperature Fraction:

In this operation whole mixture is cooled and liquefied mixture (liquid) is subjected to distillation at low temperature. The production of low temperature can be done by external cooling agencies or by self expansion against resistance or no resistance. The effectiveness of this technique has resulted in cheap production of polymer grade olefins. Different feed stocks ranging from ADU, casing head to cracker gases can be liquefied. Separation of the gas containing C1 to C3 components is discussed here. The dried gas when cooled to55 to 60 Degrees cent grade under a pressure of 35 atmospheres, ethane-ethylene fraction condenses, while methane, nitrogen, hydrogen and carbon monoxide remain as gases. Hence it is desirable to operate the column more specifically, reflux drum under those conditions. After the non- condensable gases are removed, the liquid fraction containing ethane- ethylene can be distilled separately in column that contains 60 plates and operates at 20Kg/cm pressure. The reflux is maintained around -30 degrees cent grade.
This way ethylene is separated out as distillate and ethane as residual product.
So far, the above mixture has been dealt assuming up to C2 fraction is available.
In case C3 fraction is also available, this is first liquefied by using a separate column operating at- 10 degrees cent grade under 25 Kg/cm2 pressure. Usually a 35 plate column in desired to separate C3 fraction from all the more volatile fractions up to C2. After collecting the C3 fraction in liquid state, a separate column of the same order is pressed into service for separation of propylene from propane. From this it is clear that the increasing pressure naturally elevates the operating temperature or vice versa.

(H) Adsorption:

In the earlier stages of application, adsorption was considered to be an operation of purification. Various Kinds of impurities ranging from color donating substances to corrosive and toxic chemicals were attended by this process. Use of charcoal in masks at war field or bone charcoal for bleaching sugar solution was authentic. Tswetts application of selected adsorbents, for separation and isolation of pigments and natural colors, has gradually instituted chromatography, a modern tool of chemical analysis. In all these applications natural absorbents have been gradually replaced by synthetic ones. The use of natural absorbents, like bentonite clay, Fullers earth, and bauxite has been received with wild acclaim for decolonization of lube oils in petroleum industry. Though the hydrodesulphurization technique has gained momentum to interlace all the petroleum and chemical industries, still orthodox refiners are continuing the old clay treatment process.

(I) Extractive Distillation:Separation of Styrene:

Styrene is obtained as byproduct during cracking of naphtha for ethylene and it constitutes about 4 to 6%. The cracked fraction can be used as a raw material without any treatment for recovery of styrene although it is highly advantageous to tailor the fraction to C8 cut only, to raise the concentration of styrene to greater than 30%, (Boiling range of such stream is 125-148 degrees cent grade). Especially styrene O-xylene separation is a difficult thing because of close boiling ranges of these two. Extractive distillation is successful in separation of these two. Initial separation may be done by extraction or distillation to concentrate C8 fraction from the rest. Separated C8 fraction is sent into an extractive distillation unit, where a suitable solvent encounters the feed. The solvent styrene from a high boiling mixture and crude xylenes leave the tower from the top of column. The residue obtained from the bottom of this column contains styrene, a high boiling mixture and crude xylenes leave the tower from the top of column(1).The residue obtained from the bottom of this column contains styrene and solvent. This solvent mix is distilled again in second column to free styrene as a top product. Rich mixture of solvent and heavy ends formed due to polymerization of styrene goes into a separate column, where pure solvent is set free from the bottoms of the column. Polymer wastes are discarded. To prevent polymerization of the styrene small amount of inhibitor is added. STEX27 process uses a special solvent for this operation, though phenol is the best suggested one.

Artical 2 Chemicals from Methane:

(A) Introduction:

Methane is simplest of all hydrocarbons and available in nature as a major constituent of natural gas. Besides this, associated gas and gases from crude distillation (atmospheric) and cracking units are also abundant sources of methane. Methane and ethane are substantially soluble in liquid petroleum and the solubility is around 0.22 cubic meters per standard barrel Kg/ cm2 pressure difference. Thus the rereservoir fluids are bound to contain 18 to 25 cubic meters of gas per a barrel under the reservoir conditions. Surfacing of these fluids naturally free a huge quantity of gas, in the form of associated gas, at the side of mine it. Remaining dissolved gas is expelled during distillation of crude. Naturally the value of any hydrocarbon is the highest when it is converted into petrochemical. Originally natural gas was used either in heating installation or in carbon black industry. Presently the uses are many and the chemistry is profusely relevant. In fact the age old reservation of hydrocarbon of higher molecular weight for petroleum chemicals has been shifted towards methane, especially after the process like oxidative pyrolysis and electro-cracking. With large number of commodity chemicals potentially accessible through C1-C2 chemistry like ethylene glycols, acetic acid, ethanol and higher alcohols, the subject is drawing constant attention of the manufacturers. Agist of such reactions has been focused by Aquilo et al. and R. K. Gupta et.al. (1) and (2).

(B) Some more Methane Reactions:


(C) Production of methanol by oxidation:

Oxidation of methane is carried out by oxygen. Methane to oxygen ratio is maintained at 9: 1 and under the pressure of 100 atmospheres the oxidation of methane takes place at a temperature of 360 degrees cent grade. This gives a product stream containing 17% methanol, 0.8% formaldehyde and the rest is mixture of carbon and steam. It is found that the pressure and ratio of methane to oxygen favor the formation of methanol over formaldehyde. With addition of ethane to methane stream the situation has been changed in favor of methanol resulting up to 30% this helped in a considerable reduction in temperature of reaction. Catalysts like nitrogen oxides, hydrogen chloride, and metal phosphates are in use for this reaction. This is said to be an obsolete route and the new route namely through oxidative pyrolysis has become attractive.

(D) Methanol from Synthesis Gas:

Carbon monoxide and hydrogen obtained from steam reforming operation are relatively free from detrimental components, if carbon monoxide should be obtained from metallurgical industries; it has to be purified vigorously. The reaction between carbon monoxide and hydrogen is simple catalytic and resembles closely ammonia synthesis CO + 2H2CH3 OH +125.5 KJ/mol Equilibrium yields are shown in table 2.2 for different temperatures and pressures. Because of the less conversion, recirculation of the products for many times is UN available. Basically there are three technologies well explored for methanol synthesis. These being high, pressure low pressure synthesis and liquid phase technology. High pressure synthesis offered by ICI, Lurgi, and TOPSOE etc. operates in the pressure range of 30 to 35 MPa and temperature between 360 -400 degrees cent grade. Catalyst used being zinc oxide chromium oxide mixture. Low pressure synthesis is also offered by TOPSOE, ICI, Lurgi and others, and has been readily accepted by the industry. The conditions are milder, i.e. pressure in the range of 5-10 MPa and temperature in the range of 220- 350 degrees cent grade. Zinc Chromium catalyst has been replaced by copper based catalyst. Liquid phase synthe sis develops by chem. Systems uses fluidized bed reactor. The catalyst like the oxides of zinc-chromium resists high temperature but poisoned easily. Some times, oxides of alkali metals are doped on these oxides to promote higher alcohols. Oxides of nickels and iron are found to be active chain generators. Though vanadium - zinc - chromium catalysts are selective to reactions, not susceptible to poisons and high temperature. The synthesis takes place over a bed of heterogeneous catalyst in adiabatic beds or in tubes packed with catalyst. As the oxidation generates a lot of heat, heat removal assists the forward reaction; hence cooling of the reactants at intermediate stages is required. Fig. 2.2 gives the out lines of the process. The purified gas mixture, carbon monoxide and hydrogen in required mole ratio is compressed to200 bars and mixed with hot recycle gas and fed into the converter from the top. Multiple bed converters easily facilitate the heat disposal. Initial heating of the reactor through external agency will sustain the reaction. The product gases are heat exchanged with feed to be cooled and these are separated in a high pressure separator. The liquid products from the bottom of the separator are taken to purification unit, where a battery of fractionating columns separates formaldehyde and methanol. The purge gas from the separator is recycled back. A high space velocity or contact time as small as 10 seconds is preferable. Industrially a rate of 600 cubic meters per hour per Kg. catalyst is maintained. About 2500 cubic meters of gas mixture is required per ton of methanol. Present day capacity of the plants is raised to 2,500 TPD per reactor for economy. Convincingly, fluidized bed reactors, (The fluidization is done by inert hydrocarbon like methane or ethane) developed by chem. System, give a high conversion of15 to 20 % against the conventional fixed bed of 5 to 6 %. Presently, the tendency of using both carbon monoxide and carbon dioxide is gaining significance after the significant disclosure by CPI-Vulcan process. Mitsubishi Chemicals employs Zinc - Boron - Copper catalyst that functions under a pressure of 50 to 200 bars and temperature of 300 degrees cent grade.


(E) Uses of Methanol:

Methanol is mostly used as a chemical intermediate and 50% of it is usually converted into formaldehyde. Dim ethyl terephthalate, methylamines, methacry lites, methyl halides are some of the important derivatives of methanol. Presently methanol has gained importance as a component to gasoline -alcohol mixtures for petrol engines, due to the fact of rising prices of oil and in impending pollution laws. Chang and Silvestri, Dejajaifve et. Al (4) & (5) has used ZSM series of catalyst of small pore to study the conversion of methanol to hydrocarbons. Later on the well known process for methanol to hydrocarbons and gasoline known as Mobile process has come into operation.

(F) Mobil Process:

Methanol can be converted to light olefins over an acid catalyst, which are then oligomerised or cyclised to aromatics over zeolite catalysts. This process can limit the chain growth to maximum C10, thus fitting in the range of gasoline. Dehydration of methanol is successfully carried over -AL 2O3 to yield olefins. About 75% of methanol is converted to C5+ gasoline. Fischer Tropschs process has also given its share to convert methanol to hydrocarbons of high octane value, through the following reaction:

Conventionally, the source for such reaction is a mixture of carbon monoxide and hydrogen rather then methanol. According to Inui & Takequani, methanol can also be converted to olefins in a flow reactor over zeolite catalyst at atmospheric pressure in presence of nitrogen. With high space velocity of 1000 to 4000 hr at a temperature range of 300 to 400 degrees cent grade. A dilute mixture of 10 to 20 % mole per cent methanol and rest being nitrogen gives the following spectrum of product. Methanol seems to yield 30-60% ethylene can yield not more than 30% ethylene, a definite advantage to be utilized in future. Further silicate catalyst developed by Union Carbide with Mn-Fe deposits produce at moderate conditions, 30-35% olefins of C2-C4 range and 30% aromatics. Medium pore zeolites of Mobil also contribute aromatics because of the acidity of zeolites.

(G) Isobutylene from methanol:

A stream containing 8 to 15% by weight of i-butane can be produced from methanol by using silicate catalysts impregnated with oxides of thorium zirconium, titanium etc. Isobutylene is an important raw material in the manufacture of methyl-t- butyl ether, butyrubber, polybutenes etc. MTBE is used as an additive to gasoline. Methanol conversion is pronounced at 380 degrees cent grade, and HSV of 10 -11.

(H) Formaldehyde:

Formaldehyde is obtained mainly as a constituent in the oxidation products of paraffin's, especially methane. However its separation in pure form becomes uneconomical. It can be cheaply produced either by dehydrogenation or oxidation of methanol. Oxidation is carried over a silver gauge or finally made copper gauge. Methanol to air ratio is kept in 0.3 to 0.5 the reaction is carried in vapor phase at 450-600 degrees cent grade under atmospheric pressure. Lumuus and Montecatni developed iron-molybdenum combinations for smooth oxidation in fixed bed reactors. The catalysts can with stand poisons and give higher yields. Methanol is first heat exchanged and sent into a vaporizer (A). The vapors are mixed with required amount of air and sent into reactor (B) where the silver gauge is spread in three or four levels which can help in cooling the gases. The out going gases exchange heat and goes into an absorber (C), where stream of water absorbs formaldehyde and un reacted methanol. The dilute mixture is distilled to separate formaldehyde in form of solution, methanol in the form of vapor in fractionators (D). Methanol vapor are cycled back to the process. The exhaust gas contains carbon dioxide and air.

(I) Acetic Acid:


(J) Ethylene Glycol:


(K) Hexamethylene Tetra mine:

Formaldehyde reacts with ammonia to form hexamethylene tetra mine, which is used in plastic industry and in pharmaceutics too.

Formaldehyde solution reacts with anhydrous ammonia in a cooled reactor. The product is cooled purified by evaporation and centrifuging. After the centrifuging the crystals are dried and the mother liquor is recycled back to the reactor.

(L) Ethanol:

The synthesis of ethanol from methanol provides an example of reductive carboxylation chemistry.

The technical limitation of methanol homologation to ethanol is found in catalyst activity and selectivity. Cobalt carbonyls mixed with ruthenium have been found to be useful in enhancing ethanol production rather than simple cobalt carbonyls.

(M) Halides of methane:

All the halides of methane can be indirectly produced from methanol. The direct halogenations of methane, leads to the higher halogenated products than the simple methyl halide. Methane is the most difficult of all hydrocarbons for any reaction; however chlorination and brominating are conducted at elevated temperatures or photo chemically. A fixed ratio between methane and chlorine can give rise to preferred chloromethane at higher yields, while other chloromethane also accompany. As an example methyl chloride can be produced by choosing very great ratios of methane to chlorine and passing over a catalyst like cupric chloride deposited on pumice at 450 degrees cent grade.

As the chlorination increases higher chlorides appear, due to overriding resonance effect over polar effect of chloride. The substitution reactions go through free radicals. Free radicals being active can bring the chain reaction mostly in un controllable way. The initial stage of formation of free radicals may be supposed to be the only difficult step in operation as shown below:

Presence of a catalyst is not necessary, as the chlorination reaction is a light sensitive one; further the fixed ratio of reactants does yield the specific chlorinated product. Thus, it is easy to produce carbon tetra chloride by recycling the intermediates, rather than to confine on any single chlorinated intermediate. A product distribution: Monochloromethane 58.5% Dichloromethane 2.3%, carbon tetrachloride 9.7% is more common in such reaction. A process for manufacturing chloromethane from methanol and chlorine has been designed by valcum Materials & Co. Methanol and hydrogen chloride are reacted in presence of a catalyst like zinc chloride at a temperature of 350 degrees cent grade to yield mainly chloride and small amount of other chloromethane. Methyl chloride is primarily consumed in silicon's production and tetra methyl lead. Other uses are in used as solvent too. Methyl chloride is used in the production of dim ethyl sulphoxide as shown be the reaction.

Methylene dichloride is a good paint removal solvent; also it is a good propellant for aerosols because of it is non flammable nature. The other products of chloro-fluorination of methane are gaining importance as refrigerants and aerosol propellants.

(M) PTFE:

The monomer of Teflon, tetra flouro ethylene is an odorless, colorless and non toxic gas (B.P.- 76.3 cent grade degrees) The heat of formation is - 152 K. cal. Characteristically higher than other monomers i.e. _ 41.12 K. cal. Teflon has become a very useful engineering plastic because of it is high thermal stability, insolubility in solvents, outstanding electrical insulating and dielectric properties and low frictional coefficient (a property suitable for coatings with waxes). It is very tough and not easily attacked by chemicals below 300 cent grade degrees. Further its resistant to heat; this quality has permitted its use in a temperature range of 300 to minus 200 cent grade degrees; in fact it is as much resistant as platinum. Flouro-chloro carbons can be decomposed over platinum at 100 cent grade degrees as shown by the following reaction:

Chloro-flourination of methane can take place in a single stage according to the following equations:

Montecatini Edison process uses chlorine and hydrogen fluoride mixture to react with methane in presence of a catalyst (chloride of metals) in a fluidized bed reactor. The mixture is recycled to allow a close control over reaction temperature which is in the range of 370 to 470 cent grade degrees at a pressure of 4 to 6 bars. Outlines of this method are shown in Fig.2.4.

Fluorocarbons are purified after absorbing the acid gas by water wash and later sodium hydroxide wash. The yield of carbons on the basis of methane is well above 99%.

(N) Methyl Amines:

Like chloromethane, ammonia can give rise to three amines namely primary, secondary and tertiary. A continuous process for the manufacture of mono, di and tri-methylamine consist of reaction between ammonia and methanol in a fixed bed reactor containing dehydration catalyst. Catalyst like silica, alumina gels function at a pressure of 6- 12 atmospheres and a temperature of 380- 450 cent grade degrees. The ratio between methanol and ammonia a great influence on the product pattern. A ratio of 2:1(methanol to ammonia) gives a product containing mono, di and tri-methylamines in a ratio 43:42:33 respectively. Yield seems to be higher than 98%.

The production sequence is shown in the fig. 2.5. The product of all these three amines is separated in a battery of distillation columns. Trim ethylamine- ammonia from a zoetrope; hence go back as recycle mixture to the first column itself. It can also be separated by extractive distillation with water. The reaction water may be separated immediately or can be distilled after tri-methylamines distillation. From the next column excess of TMA comes out as a top product while the bottoms of the column contain DMA and MMA. The mixture is fractionated in two distillation columns, while the liberated vapors are cycled into the process. Amines are used as intermediates. Dim ethyl amine is used for producing dim ethyl form amide, a solvent and substance used in plastic according to the following reaction:

(O) Carbon Disulphide:

Carbon disulphide is produced by reacting sulphur in vapor from with methane over a catalyst like alumina gel or synthetic clay. Drastic heating is foremost important. Lower conversion rates demand recirculation of exhausts. The reaction occurs in different ways.

Another route is by oxidation.

This reaction is desirable when alternative economic routes are not insight. Carbon disulphide is consumed to a maximum extent in rayon industry and the remaining goes for carbon tetrachloride. Carbon tetrachloride production is done by chlorination of CS2.

(P) Hydrogen Cyanide:

Hydrogen cyanide seems to be an unconventional product of methane. It is produced by oxidation of natural gas or methane in presence of ammonium over a platinum gauge, which acts as catalyst. The oxidation raises the temperature to 1000 cent grade degrees. The effluent gases cooled in heat exchangers and then scrubbed with dilute sulfuric acid to remove ammonia. The remaining gas is cooled, compressed and absorbed in water. Dilute gas solution is heated to expel the gas in pure form. Ethylene cyanohydrins can be obtained by reacting hydrogen cyanide with ethylene oxide. Fig. 2.6 shows the outlines of hydrogen cyanide production.

(Q) Liquid Fuels from Methane:

A novel method of conversion of methane to liquid fuels, through free radical oligomerisation over ZSM-5 catalyst has been presented by fox et al. Methane is selectively oxidized in a circulating fluid bed reactor, with reducible metal oxide catalyst to produce free radicals, which can later combine in a reactor over ZSM-5 catalyst to yield various olefins and oligomerisation products. With oxygen, at elevated pressure 4:1 methanol and formaldehyde can be produced, which can also be oligomerised. Third method consists of methane ox chlorination under pressure over CaCI2- KCI catalyst to yield mono and dichloride methane. These are oligomerised to liquid fuels mainly gasoline. Thus oxidation, partial oxidation, ox chlorination products can be compelled to give rise to gasoline type fuel.