Prices ethane

One of the sources predicts that ethane prices will reach 1.1—1.3 /lb and propane prices 1.2-1.4 /lb on the Gulf Coast in the mid 1970 s. 

The technology profits from the extensive experience gained by the oxychlorination of ethylene, but is based on a completely different catalyst. The new process claims a cost reduction of about 30%, because the ethane price is about one third that of ethylene. 

Ethane prices are generally determined by local circumstances. The floor price for ethane is set often priced according to the price of gas on an energy basis. For example in the US for flexible fuel cracking operations can use both ethane and naphtha if demand falls then ethane can be left in the gas stream and sold as gas. The US Energy Information Administration collates data for the well-head gas price. The data is shown in Figure 3.7. 

For some countries the cracking operation is based entirely on ethane and petrochemical operators enter take or pay contracts for ethane. Often there is a fixed-variable component in the contract linking ethane price to the prevailing price of crude oil. Obviously this limits the benefits to the operator in times of rising oil price with some or all of the benefit passed on to the ethane supplier. 

The procedure adopted is to establish a base case, which is representative of the average operation of interest and then to address the sensitivity of the base case against the key economic variables. The base case is developed around the production of 500,000 t/y ethylene using ethane at a cost of 7.19/GJ ( 373.3/t). This ethane price is discussed in an earlier chapter and corresponds to a natural gas price of S6.37/GJ (average US 2007 price) into a suitably large-scale gas plant. 

The production economics can be estimated as a function of ethane price using the assumptions ... 

Setting the ethane price to 7.19/GJ (which corresponds to a gas plant price with gas available at 6.37/GJ) gives the ethylene production cost of 726/tonne for the OPEN system and 869/toime for the CLOSED system. The cash flows are detailed in Table 7.3. 

For ethane feedstock, of most interest is the sensitivity of the production cost to the price of ethane. In many jurisdictions, the ethane price is related to the price of gas. In turn this is related in many parts of... 

Figure 7.6 Ethylene from ethane - sensitivity to ethane price...

Small scale operations are widely used to produce small amounts of ethylene for a specific purpose (e.g. styrene). This graph illustrates that high ethane prices are a significant threat to these operations because the cost of ethylene transport from a larger operation (typically 100/t for ship based transport) is lower than the rise in production cost due to the loss of economy of scale. 

Comparing the smaller scale operations with access to low ethane prices shows that these are competitive with much larger operations paying high ethane prices. 

Figure 7.9 Impact of ethane price on the polymer margin...

The graph clearly demonstrates the competitive advantage of operations with ethane tied to a low cost gas price (ethane prices < 4/GJ) compared to those operations with ethane linked to the price of oil. 

Because of the large price differential between propane and propylene, which has ranged from 155/t to 355 /1 between 1987 and 1989, a propane-based process may have the economic potential to displace propylene ammoxidation technology eventually. Methane, ethane, and butane, which are also less expensive than propylene, and acetonitrile have been disclosed as starting materials for acrylonitrile synthesis in several catalytic process schemes (66,67). 

Fig. 2. Quarterly olefin feedstock prices, 1978—1991, for (D) ethane (+) propane (<)) light naphtha, and (A) naphtha.

Fig. 3. Price ratio of various feeds to ethane, 1978—1991 (D) propane—ethane, (+) light naphtha—ethane, and (<)) fuU-range naphtha—ethane.

The market value of natural gas Hquids is highly volatile and historically has been weakly related to the world price of cmde oil. During the 1980s, the market value of natural gas Hquids ranged from approximately 60% of the price of cmde to 73% (12). In this 10-year interval, several fluctuations occurred in the natural gas Hquid market. Because of the variabiHty of the natural gas Hquid market, the NGL recovery plants need to have flexibiHty. Natural gas Hquid products compete in the following markets ethane propane a Hquefted petroleum gas (LPG) a C-3/C-4 mix and / -butane all compete as petrochemical feedstocks. Propane and LPG are also used as industrial and domestic fuels, whereas 2-butane and natural gasoline, consisting of C-5 and heavier hydrocarbons, are used as refinery feedstocks. 

Berners-Price, S., Mirabelli, C.K. and Johnson, R.K. (1986) In vivo antitumor activity and in vitro cytotoxic properties of bis[l,2-bis(diphenylphosphino)ethane] gold(I) chloride. Cancer Research, 46, 5486-5493. 

Cracking large hydrocarbons usually results in olefins, molecules with double bonds. Thats why the refinery cat crackers and thermal crackers are sources of ethylene and propylene. But the largest source is olefin plants where ethylene and propylene are the primary products of cracking one or more of the following ethane, propane, butane, naphtha, or gas oil. The choice of feedstock depends both on the olefins plant design and the market price of the feeds. 

Table 8.1 shows the stochastic model solution for the petrochemical system. The solution indicated the selection of 22 processes with a slightly different configuration and production capacities from the deterministic case, Table 4.2 in Chapter 4. For example, acetic acid was produced by direct oxidation of n-butylenes instead of the air oxidation of acetaldehyde. Furthermore, ethylene was produced by pyrolysis of ethane instead of steam cracking of ethane-propane (50-50 wt%). These changes, as well as the different production capacities obtained, illustrate the effect of the uncertainty in process yield, raw material and product prices, and lower product... 

The prices and values shown must be considered as illustrative only rather than as an attempt to predict the future. They are based generally on literature data averages and on discussions with a number of chemical and refining companies. While the figures used are generally representative of present price levels, in some cases a simplification is used—e.g., taking ethane, propane, and butane prices at 1 cent/lb. 

In the United States. With premium by-product prices prevailing, ethylene can be made from n-butane more cheaply than from either ethane or propane, assuming these light hydrocarbon feeds would be all available at 1 /lb. 

Figure 6 shows that with the present level of premium valuation for by-products, a 1.1 /lb naphtha price would result in this feedstock having an advantage over ethane, propane or butane at 1 /lb. The cost for naphtha-based ethylene in this case would be only 1.94 /lb vs. 2.04, 2.36, and 2.47 /lb from n-butane, propane, and ethane, respectively. The breakeven prices for the light feedstocks that would correspond to the 1.1 /lb naphtha price would be 0.6, 0.82, and 0.95 /lb for ethane, pro-... 

---