Maintenance costs for

When estimating the operating and maintenance costs for various options, it is recommended that the actual activities which are anticipated are specified and costed. This will run into the detail of frequency and duration of maintenance activities such as inspection, overhaul, painting. This technique allows a much more realistic estimate of opex to be made, rather than relying on the traditional method of estimating opex based on a percentage of capex. The benefits of this activity based costing are further discussed in Section 13.0 and 14.0. 

When abrasive solid particles must be suspended, maintenance costs for the submerged shaft seal of a side-entering propeller may become high enough to make this type of mixer an uneconomical choice. 

The chief factors determining the size of grinding balls are fineness of the material being ground and maintenance cost for the ball charge. A coarse feed requires a larger baU than a fine feed. 

Maintenance on gas trucks is also higher than with electric vehicles. About 5 percent annually of the initial cost applies to internal-combustion equipment, and about 2 percent annually to electric. A special feature on electric trucks with solid-state controls is the use of modules or circuit boards, which can be replaced as units and rebuilt at the factoiy. Typical maintenance costs for trucks operating five 8-h shifts per week are in the order of 3.15 per hour for gas vehicles and 1.78 per hour for electric ones. Under these conditions, energy costs are typically 9.3 cents per hour for gas trucks and 5.1 cents per hour for the electric units. 

Operating and maintenance costs for safety instruments and interlocks, fire protection systems, personal protective equipment, and other safety equipment. 

Increased maintenance cost for process equipment due to safety requirements (for example, safety permits, cleaning and purging equipment, personal protective equipment, training, and restricted access to process areas). 

Reduction in maintenance costs for the building fabrics, machinery, and products... 

LCC y[ = present value of maintenance cost E = maintenance cost for one period p = expected annual rise of maintenance cost... 

The tender with the lowest total costs (sum of investment, energy and maintenance costs) is the best and the supplier guarantees energy, and maintenance costs for, say, a three-year period. If the target costs are exceeded, the supplier pays a penalty if the operating costs are lowered, the supplier and the customer share the bonus. 

In the fluidized bed process, attrition caused dry sorbent to be carryover. This mainly occurred in the early stage of fluidization and was highly affected by gas velocity. The amount of attrition of molecular sieve 5 A and molecular sieve 13X were larger than those of activated carbon and activated alumina. In addition, percentage losses of adsorption capacities of molecular sieve 5A and molecular 13X were 14.5% and 13.5%, whereas those of activated carbon and activated alumina were 8.3% and 8.1%, respectively. This is because retention time of molecular sieve 5A and molecular 13X decreased due to elutriation of particle generated from attrition. Also, Ka of activated alumina and activated carbon were the lower than those of Molecular sieve 13X and 5A. Consequently, molecular sieve 5A and molecular 13X could cause high maintenance cost for dry sorbent and problems in the operation of fluidized bed process. 

This item will include the cost of maintenance labour, which can be as high as the operating labour cost, and the materials (including equipment spares) needed for the maintenance of the plant. The annual maintenance costs for chemical plants are high, typically 5 to 15 per cent of the installed capital costs. They should be estimated from a knowledge of the maintenance costs on similar plant. As a first estimate the annual maintenance cost can be taken as 10 per cent of the fixed capital cost the cost can be considered to be divided evenly between labour and materials. 

The maintenance cost for the system has been budgeted to 3,200 Euro/year, and the energy cost for running the pumps in the system approx. 6,800 Euro/year. The calculated savings based on these figures are 15,000 Euro/year. This will result in a straight payback time of some 10 years. 

A 200-ft mobile TechXtract processing unit reportedly had an initial capital cost of 42,000. This unit was capable of processing up to 10,000 lb of contaminated solids per day. Operation and maintenance costs for the unit were 5 per pound (D19069W). 

Because the ASH technology has varied uses in the remediation and industrial sectors, costs will depend on the specific application. According to Advanced Processing Technologies, Inc. (APT), operation and maintenance costs for an ASH system that can process 50 tons of soil per hour are 2 to 5 per ton of soil treated. This estimate also includes labor costs. To process a steady feed stream of 10 to 20 gal/min of wash-rack wastewater, operational costs are 0.60 to 1.50 per 1000 gal of water treated. The capital costs of an ASH unit for this application range from 15,000 to 30,000 (D14439I, p. 2). 

Case Study 1. Pump-and-Treat System with a Packed-Tower Air Stripper, McClellan Air Force Base Superfund Site, California, Operable Units B/C, 1987. The costs associated with pump-and-treat system used at the site were estimated in 1994. Costs were approximately 80 per pound of removed volatile organic compounds (VOCs) based on operating costs alone and approximately 150 per pound when capital costs were included (D141286, p. 135). It should be noted that the operation and maintenance costs for the an air stripper could not be separated from the total cost of the project. Capital cost and operating cost information for this project are summarized in Case Study 1. 

TABLE 1 Capital and Annual Operating and Maintenance Costs for the CHEMIC Ultraflltration Process... 

TABLE 2 Operation and Maintenance Costs for a Full-Scale, Gravel-Based Wetlands with Surface Water Discharge... 

According to the vendor, the capital costs for the treatment system include a 200-actual cubic-feet-per-minute (ACFM) vacuum pump, two transfer pumps, a carbon steel knockout pot, and associated instrumentation and piping. Operation and maintenance costs for the system include estimates for additional granular activated carbon (GAC) units, liquid- and vapor-phase analysis, weekly monitoring, electricity, and routine maintenance. These costs vary, depending on the monitoring requirements, contaminant concentrations, and other variables (D13124Y, p. 492). 

Pilot testing shonld cost less than 10,000 inclnding analysis fees if an extraction or test well of at least 6 inches in diameter is available. Annnal operation and maintenance costs for the existing system have been abont 1750 for quarterly maintenance of the air compressor. All estimates are in 1996 dollars. In addition, about 40 hr of staff time has been nsed for routine inspections of the system (D148930, p. 4). 

The vendor states that savings associated with the EnviroMetal Process are due to the low operation and maintenance costs for treatment walls. Because contaminants are destroyed rather than removed, process monitoring costs are negligible, and little or no waste products require disposal or regeneration on a regular basis. The vendor also states that since the technology is a passive treatment, there is no need for manual labor to operate, monitor, and maintain the system (D14522C, pp. 19, 20). 

Some generalizations can be made about this class of photocatalytic oxidation technologies. Because of the systems unattended operation and readily available parts, operation and maintenance costs for these technologies are very low. In one extended field application, direct operating costs were 1 to 2 per 1000 gal of water treated (D108214, p. 311). 

Based on the demonstration funded by the U.S. Environmental Protection Agency in Frederick, Maryland, the vendor estimated the costs associated with building and maintaining a Living Machine for the treatment of municipal wastewater. Table 1 displays the capital costs for Living Machine systems that process 40,000 gal per day (gpd), 80,000 gpd, and 1,000,000 gpd. The operations and maintenance costs for the systems are shown in Table 2. Table 3 demonstrates the total annual costs for the systems (D22581K, pp. 13-9-13-13). 

TABLE 2 Estimated Annual Operation and Maintenance Costs for a Living Machine Municipal Wastevrater Treatment Plant... 

Remtech s Bubble Lance Low-Profile Stripper (BLLS) is a diffused air, shallow channel, low-profile air stripper. The BLLS is designed to reduce operation and maintenance costs for groundwater and wastewater cleanup over conventional diffused air or plate strippers. According to the vendor, the system has the following features ... 

According to the vendor, estimated maintenance costs for a frozen barrier located on a 10-acre site with favorable soil conditions ranges from 2000 to 4000 per month. When installation is complete, it is assumed that scheduled maintenance is required D18426T, p. 2). Table 1 gives vendor-provided installation, operation and maintenance (O M), and removal costs on the basis of dollars per square foot of barrier face area ( /ft ) for frozen soil barriers of various depths (D120570, p. 27). 

A UV/ozone Ultrox system was used to treat wastewater contaminated with phenol and polychlorophenol (PCP) at a wood processing facility in Denver, Colorado. The capital cost for the Ultrox system was 200,000. Operation and maintenance costs for the entire remediation system were 10.92 per 1000 gal of treated wastewater. This cost estimate excludes the expenses associated with site preparation, permitting and regulatory compliance, startup, analysis, effluent disposal, and demobilization (D205505, p. C-1). 

The adsoiptive capacity of carbons is obviously finite. Consequently, it is gradually decreased and finally exhausted after the adsorption of the maximum possible amount of a substance. The exhausted carbon is then characterized as spent and has to be regenerated, reactivated, or properly disposed off. The regeneration of spent adsorbents is the most difficult and expensive part of adsorption technology. It accounts for about 75% of total operating and maintenance cost for a fixed-bed GAC operation. 

Fixed cost indicator is derived form the total capital cost of the system. It defined as 5% of capital cost. It comprise operational and maintenance cost for whole system, including hydrogen production and its utilization for the electric energy production. 

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