Liquid capital cost

In the case of a liquid recycle, the cost of this pressure increase is usually small. Pumps usually have low capital and operating costs relative to other plant items. On the other hand, to increase the pressure of material in the vapor phase for recycle requires a compressor. Compressors tend to have a high capital cost and large power requirements giving higher operating costs. 

Fixed opex is proportional to the capital cost of the items to be operated and is therefore based on a percentage of the cumulative capex. Variable opex is proportional to the throughput and is therefore related to the production rate (oil or gross liquids). Hence,... 

Some processes use only one reactor (57) or a combination of liquid- and vapor-phase reactors (58). The goal of these schemes is to reduce energy consumption and capital cost. Hydrogenation normally is carried out at 2—3 MPa (20—30 atm). Temperature is maintained at 300—350°C to meet a typical specification of less than 500 ppm benzene in the product at higher temperatures, thermodynamic equiUbrium shifts to favor benzene and the benzene specification is impossible to attain. Also, at higher temperatures, isomerization of cyclohexane to methylcyclopentane occurs typically there is a 200 ppm specification limit on methylcyclopentane content. 

The main factors in the design of an adsorption system are the (1) Carbon consumption - The amount of earbon required to treat the liquid or gas, normally expressed per unit of the fluid treated and (2) Contact time - For a fixed flow rate, the contact time is directly proportional to the volume of carbon and is the main factor influencing the size of the adsorption system and capital cost. 

The advantages of thermal incineration are that it is simple in concept, has a wide application, and results in almost complete destruction of pollutants with no liquid or solid residue. Thermal incineration provides an opportunity for heat recovery and has low maintenance requirements and low capital cost. Thermal incineration units for small or moderate exhaust streams are generally compact and light. Such units can be installed on a roof when the plant area is limited. = The main disadvantage is the auxiliary fuel cost, which is partly offset with an efficient heat-recovery system. The formation of nitric oxides during the combustion processes must be reduced by control of excess air temperature, fuel supply, and combustion air distribution at the burner inlet, The formation of thermal NO increases dramatically above 980 Table 13.10)... 

The difference between the actual sales price of the liquid and the break-even price of the liquid in Table 9-3 provides the income to pay out the capital cost, fuel cost, and other operating and maintenance expenses necessary to make the recovery of the gas economically attractive. 

Fatal accident rate Lost-time injury rate Capital cost of accidents Number of plant/community evacuations Cost of business interruption Cost of workers compensation claims Number of hazardous material spills (in excess of a threshold) Tonnage of hazardous material spilled Tonnage of air, water, liquid and solid effluent Tonnage of polluting materials released into the environment Employee exposure monitoring Number of work related sickness claims Number of regulatory citations and fines Ecological impact of operations (loss or restoration of biodiversity, species, habitats)... 

Dr. Blum Our office in New York has done several economic analyses. The distinct advantage of liquid-phase methanation, other than the fact it does not have recycle cost, is that it requires only about 60% of the capital cost. For a commercial plant of 250 billion Btu per day, the capital cost is projected at about 18,000,000. Since the operating costs depend very substantially on the capital costs, there is a very big reduction in operating costs. We project at the moment an advantage in the order of four to six cents per million Btu over cold gas and hot gas recycle. 

A stripper operating at a high pressure drop will require a smaller volume than a similar stripper at a lower pressure drop. This reduces the capital cost for the tower, but increases the blower cost. Towers designed and built to operate at a low pressure drop have the flexibility to increase the gas flow rate and hence the air/water ratio, should the future influent concentration increase or the effluent limitation decrease. Towers designed for high pressure drops do not have this flexibility in operation and would need to decrease the liquid loading to increase the air/water ratio. 

The capital cost of the storage equipment will be approximately proportional to the storage capacity. This involves the capital cost of storage tanks in the case of gases and liquids, and silos in the case of solids, capital cost of... 

An open cylindrical vessel is to be used to store 10 ft3 of liquid. The objective function for the sum of the operating and capital costs of the vessel is... 

At these lower conversions, the previously described multi-bed down-flow reactor may not be the best design. At the higher space velocities it is more expedient to have the liquid in up-flow, and the reduced penalty from axial (particularly) forward mixing means also that the necessary conversion can frequently be achieved in a single catalyst bed. Thus, the reactor design is considerably simplified, with an associated reduction in the capital cost for a given catalyst volume. The development of the design for an up-flow-packed bed reactor for the decomposition of sodium hypochlorite is described elsewhere [6] and will not be considered in detail here. 

Estimates of capital costs of GTL plants display a wide range while the EIA (2006) indicates capital costs at US 25 000 45 000 per barrel of daily capacity, depending on production scale and site selection, the IEA (2006) reports capital costs of GTL plants currently completed or under construction with US 84 000 per barrel. By comparison, the costs of a conventional refinery are around 15 000 per barrel per day. Gas-to-liquid is assumed profitable when crude oil prices exceed 25 per barrel and natural gas prices are in the range of 0.5-1.0/GJ (EIA, 2006). The economics of GTL are extremely sensitive to the cost of natural gas. 

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