Supply lower operating costs

A well-located refinery has lower operating costs and increased operating flexibility. When located near other refineries and petrochemical plants in a coastal industrial basin such as Rotterdam, the Houston Ship Channel, etc., it has access to a wide variety of crudes, blend stocks, transportation options, additives, supplies, and services. This enhances its ability to cope with upsets and to react aggressively to sudden changes in price differentials. 

TES-based systems are usually economically justifiable when the annualized capital and operating costs are less than those for primary generating equipment supplying the same service loads and periods. TES is often installed to reduce initial costs of other plant components and operating costs. Lower initial equipment costs are usually obtained when large durations occur between periods of energy demand. Secondary capital costs may also be lower for TES-based systems. For example, the electrical service equipment size can sometimes be reduced when energy demand is lowered. 

The need to neutralise immediately after sulphation also changes the mode of use and the economics of alkyl sulphates compared to LAS which is commonly traded as the free acid at typically 97% active matter. This reduces the price (fewer unit operations, hence lower manufacturing costs) and transport costs per unit of active matter and gives the formulator freedom of choice in counter ion and concentration of the final surfactant. Since this is not possible with AS, the manufacturer must neutralise the sulpho acid, often needing to add a buffer and preservative. (This increases the price paid to the supplier, but not necessarily the total cost of the surfactant in formulation.) Most alkyl sulphates are supplied as 20-30% active solutions, so the transport cost per unit of active matter is 3-5 times higher for LAS. 

Typically, the air-stripper manufacturer will supply liquid flow ranges acceptable for a particular tower. Selecting an air stripper for which the design flow is at the lower end of the tower s rated capacity will produce high contaminant removal rates, but may not optimize power requirements. For large-scale systems where significant operational costs may be incurred by overdesigning the system, the use of pressure-drop curves and calculations such as Eqs. (1)-(13) are required. 

Peat is used in Sweden as a fuel in electricity and heat production and corresponds to about 1.3 Mt CO2 per year. Currently, peat is exempt from CO2 tax. Moreover, if peat is used as a fuel for electricity production, the operator will receive green certificates, which can be sold. With the introduction of the EU ETS, operators using peat will need to acquire allowances, which will increase the operators costs for using peat considerably. Calculations have shown that if allowances prices rise above 20-25 per ton CO2, operators will shift from peat to alternative fuels, such as coal (cheaper), or natural gas or bio-fuels (lower emissions). As a result it is possible that the use of peat for energy supply will be significantly reduced. 

EDLs are very intense, stable emission sources. They provide better detection limits than HCLs for those elements that are intensity-limited either because they are volatile or because their primary resonance lines are in the low-UV region. Some elements like As, Se, and Cd suffer from both problems. For these types of elements, the use of an EDL can result in a limit of detection that is two to three times lower than that obtained with an HCL. EDLs are available for many elements, including antimony, arsenic, bismuth, cadmium, germanium, lead, mercury, phosphorus, selenium, thallium, tin, and zinc. Older EDLs required a separate power supply to operate the lamp. Modern systems are self-contained. EDL lamps cost slightly more than the comparable HCL. 

During the latter half of the 20th century, successive improvements in ammonia production have lowered-the-cost to the point that its liberal use in crop production is economically attractive. Notable among these improvements was perfection of processes for reforming natural gas or naphtha to supply the hydrogen-nitrogen synthesis gas and to increase the scale of operation. 

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