Agriculture

APPENDIX X AGRICULTURAL PRODUCTION

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APPENDIX X

AGRICULTURAL PRODUCTION IVELISSE TUBENS1 AND MICHIEL P.H. BRONGERS1 SUMMARY Based on the 1997 Census, the total value of farm machinery and equipment is approximately $15 billion per year. The two main reasons for replacing machinery or equipment include upgrading old equipment and substitution because of wear and tear. Failure due to corrosion damage would be grouped in this category; however, national data on the types of failures occurring in farm equipment were not found. Discussions with people in this industrial sector resulted in an estimate of corrosion costs in the range of 5 percent to 10 percent of the value of all new equipment. This means that the total cost of corrosion in the agricultural production industry is in the range of $748 million to $1.498 billion per year, with an average of $1.123 billion per year. Corrosion control and prevention can be accomplished by keeping equipment clean and dry after each use, applying corrosion-resistant materials or materials with a corrosion allowance, applying external coatings (paints) or internal lining systems, or using cathodic protection. Strategies for maintaining and optimizing inspection programs for agricultural equipment (i.e., minimizing safety concerns for fertilizer tanks) with a high corrosion risk need to be developed. Development of new and improved inspection techniques is required to ensure the integrity of agricultural equipment.

TABLE OF CONTENTS SECTOR DESCRIPTION.........................................................................................................................................X1 AREAS OF MAJOR IMPACT ................................................................................................................................X2 Agricultural Fertilizers .................................................................................................................................X2 Fertilizer Tanks ............................................................................................................................................X2 Milking Process Systems..............................................................................................................................X3 Agricultural Fumigants.................................................................................................................................X3 Electrical Systems in Agricultural Buildings ...............................................................................................X3 Agricultural Vehicles ...................................................................................................................................X3 COST OF CORROSION..........................................................................................................................................X3 CORROSION CONTROL METHODS ...................................................................................................................X4 Keeping Equipment Clean / Dry ..................................................................................................................X5 Material Selection ........................................................................................................................................X5 External Coatings / Paints ............................................................................................................................X5 Internal Linings ............................................................................................................................................X5 Cathodic Protection ......................................................................................................................................X6 CORROSION MANAGEMENT ..............................................................................................................................X6 REFERENCES ...........................................................................................................................................................X6 1

CC Technologies Laboratories, Inc., Dublin, Ohio.

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Appendix X – Agricultural Production

LIST OF FIGURES Figure 1.

Illustration of 1997 major input items and expenditures in farm production in the United States, according to the USDA National Agricultural Statistics Service...................................................X1

Figure 2.

U.S. farm production expenditures for fertilizer, labor, and feed from 1992 to 1997, according to the USDA National Agricultural Statistics Service ...................................................................X2

LIST OF TABLES Table 1.

Summary of 1997 shipment values of farm machinery and equipment, according to the 1997 Census ............................................................................................................................................X4

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Appendix X – Agricultural Production

SECTOR DESCRIPTION According to the 1998 Economic Census, “agricultural operations” is defined as producing livestock, poultry, or other animal specialties and their products, and producing crops, including fruits and greenhouse or nursery products. According to the U.S. Department of Agriculture (USDA) National Agricultural Statistics Service (NASS), there are 1,911,859 farms in the United States.(1) The eight major U.S. field crops include corn, sorghum, barley, oats, wheat, rice, upland cotton, and soybeans. The major livestock are poultry, cattle, hogs, and sheep. Figure 1 illustrates the 1997 farm production expenditures by percentage in the United States. The percentage of total expenditures spent on chemicals, fertilizer, and seeds, and supplies, repair, and construction are 14.6 percent and 10.2 percent, respectively. In 1997, approximately $11 billion was spent on fertilizer (see figure 2). There was an increase in fertilizer expenditures of 27 percent in the period from 1992 to 1997. The consumption of fertilizer has increased, causing more corrosion problems in fertilizer tanks and farming equipment. According to agricultural industry experts, chemicals and fertilizer are one of the major causes of corrosion in the agricultural industry;(2-3) therefore, it can be inferred that corrosion costs are mainly due to chemical usage on agricultural equipment.

Farm Production Expenditures: Major Input Items by Percent of Total, United States, 1997 Fuel 3%

Chemicals, Fertilizer, & Seeds 15%

Machinery, Vehicles 7% Livestock 8%

Feed 14%

Interest, Taxes 10%

Labor 10%

Farm Services 13%

Supplies, Repair, & Construction 10%

Rent 10%

Figure 1. Illustration of 1997 major input items and expenditures in farm production in the United States, according to the USDA National Agricultural Statistics Service.(4)

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Appendix X – Agricultural Production

U.S. Selected Production Expenditures, 1992 - 1997 Fertilizer

Labor

Feed

27,500 25,000 22,500

Millions of Dollars

20,000 17,500 15,000 12,500 10,000 7,500 5,000 2,500 0 1992

1993

1994

1995

1996

1997

Figure 2. U.S. farm production expenditures for fertilizer, labor, and feed from 1992 to 1997, according to the USDA National Agricultural Statistics Service.(4)

AREAS OF MAJOR IMPACT Agricultural Fertilizers Corrosion problems occur in plumbing systems of agricultural sprayers when proper maintenance is ignored. Corrosion of sprayer components can be prevented by utilizing rubber components (i.e., gaskets, diaphragms, hoses, etc.) or by using motor oil in the final flushing of the sprayer.(5) An alternative to using motor oil is to use automotive antifreeze with a rust inhibitor. Furthermore, as many components as possible that are in contact with the spray solutions should be made of chemically resistant materials such as ethylene vinyl acetate (EVA) and ethylene propylene dione monomer (EPDM). The major fertilizer used in agricultural is urea ammonia nitrate (UAN). Chemicals such as anhydrous ammonia, used in farming fertilizers, are very aggressive. Inserve is an inhibitor added to anhydrous ammonia, which inhibits the biological conversion of ammonia to nitrate.(2) Nitrate, when formed, could be corrosive.

Fertilizer Tanks Fertilizer tanks are generally fabricated from ASTM A36 carbon steel. The tanks are welded externally and internally to prevent crevices and to provide maximum resistance to corrosion. However, they are susceptible to pitting and erosion-corrosion in the acetic solutions used in fertilizers.

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Appendix X – Agricultural Production

Milking Process Systems Moisture content, sanitizing chemicals, and animal respiration in milking parlors causes problems on milking parlor ceilings. In order to prevent corrosion, ceilings are constructed from painted carbon steel. Replacement of a parlor ceiling costs approximately $5,000 to $10,000.(6) Milking processing units are constructed from stainless steel and contain rubber-lined inflations in which the milk is collected. Corrosion problems occur due to hot water cycles and wash water used to clean the equipment. Replacement of a milking processing unit can cost approximately $5,000 to $10,000.(7)

Agricultural Fumigants Agricultural fumigants, such as methyl bromide and phosphine, are used to disinfect food-processing facilities. They are used to control insects, nematodes, weeds, and pathogens in more than 100 crops, in forest and ornamental nurseries, and in wood products. They are primarily used in soil fumigation, post-harvesting protection, and quarantine treatment. The use of phosphine as an alternative to methyl bromide has been a controversial issue. In 1999, the Agricultural Research Service (ARS) had a research budget of $14.4 million for seeking alternatives to methyl bromide.(7) Alternative chemicals such as phosphine have been proposed; however, phosphine in combination with carbon dioxide, heat, and humidity is corrosive to copper and electronic and electrical equipment in food-processing facilities. The corrosion kinetics of phosphine and copper are not well understood. Predictive models of potential damage will permit the development of preventive strategies that will allow continued fumigation with phosphine, but will prevent or mitigate corrosion damage to copper and other electrical conductors.

Electrical Systems in Agricultural Buildings Agricultural buildings that house livestock require special care in selecting wiring materials, wiring methods, and electrical equipment because of corrosive dust, gases, and moisture. Corrosion of metallic conduit, boxes, and fixtures frequently leads to electrical system failure. Boxes and fixtures made of a non-metallic material or corrosion-resistant stainless steel, i.e., non-magnetic, are recommended for all agricultural buildings and are required in any buildings that house livestock or contain corrosive dust. Accelerated corrosion due to condensation occurs on electrical panels that have not been properly designed.

Agricultural Vehicles According to the 1997 Economic Census Vehicle Inventory and Use Survey (VIUS),(8) 15 percent of all trucks (3.4 million of the total 72.8 million trucks) have their primary use as agricultural vehicles. The survey further noted that the specified primary products are farm products for 1.25 million trucks, live animals for 0.52 million trucks, and animal feed for 0.43 million trucks.

COST OF CORROSION Determining the cost of corrosion in the agricultural production industry is not an easy task. Economic data for this industry generally include national dollar-amount values of sold products, such as vegetables or meat, but the information is that most farms are owned and operated by individual farmers and their families. Although information on the causes of equipment failure may be known for each farm, no national organization was identified to collect this information and make the information available to the general public. The result is that each farmer is faced with solving his own corrosion problems without having a resource to help in the selection of a corrosion control method that would be the best economical solution.

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Appendix X – Agricultural Production

One method to estimate the national cost of corrosion uses the total annual value of new farm machinery and equipment. According to the 1997 Economic Census Farm Machinery and Equipment Manufacturing report,(9) the value of product shipments totaled $14.97 billion. This includes farm-type two-wheel and four-wheel drive tractors with or without attachments; farm dairy equipment; planting, seeding, and fertilizing machinery; harvesting machinery; haying machinery; parts for farm machinery; farm plows, harrows, rollers, pulverizers, cultivators, and weeders; commercial turf and grounds care equipment; and other farm machinery and equipment. Table 1 summarizes the 1997 shipment value for each of these categories.

Table 1. Summary of 1997 shipment values of farm machinery and equipment, according to the 1997 Census.

PRODUCT CLASS Farm-type 2- and 4-wheel drive tractors Diary equipment, sprayers, dusters, elevators, and blowers Planting, seeding, and fertilizing machinery Harvesting machinery Haying machinery Parts for farm machinery (sold separately) Plows, harrows, rollers, pulverizers, cultivators, and weeders Other farm machinery and equipment Commercial turf and grounds care equipment Farm machinery and equipment (not specified by kind) TOTAL

1997 SHIPMENTS VALUE ($ x million) 3,857 745 1,080 2,970 664 1,425 609 1,837 1,340 439 $14,966

ASSUMED CORROSION COST 5% 10% 193 386 37 75 54 108 149 297 33 66 71 143 30 61 92 184 67 134 22 44 748 1,498

AVERAGE: $1.123 billion per year

To analyze the total shipment value further, the reasons for buying a new piece of machinery or equipment must be determined. The two main reasons for replacing machinery or equipment include upgrading old equipment and substitution because of wear and tear. Failure because of corrosion damage would be grouped in this last category. In discussions with people involved in agricultural research and manufacturing, it became evident that no actual survey data with percentages on the types of “wear and tear” are available; therefore, an assumption as to this percentage was made as being in the range of 5 to 10 percent of the total value of new equipment and machinery shipments, with a 7.5 percent average. These percentages were included in table 1 so that an estimate of the cost of corrosion in the agricultural production industry could be determined. Although opinions on the accuracy of these assumed that percentages may vary, the authors of this sector analysis agreed that the estimate of the corrosion cost in the range of $0.75 to $1.5 billion per year is probably in the right order of magnitude. The average of this cost range is $1.1 billion per year.

CORROSION CONTROL METHODS Corrosion control and prevention can be done by keeping equipment clean and dry after each use, by applying corrosion-resistant materials or materials with a corrosion allowance, by applying external coatings (paints) or internal lining systems, or by using cathodic protection. Agricultural production occurs by working or using farmland; therefore, equipment used to work the fields is exposed to the climate and weather of that area of the country. Water from rain or wet products may collect in the

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corners or ridges of the equipment and may cause corrosion. Also, at locations where mud can build up, or where waste from the vegetables, cattle, or feed can stay behind, corrosion may occur. Another location of corrosion concern are fuel and fertilizer storage tanks on farms. The sector description on hazardous materials storage (Appendix G) describes the problems associated with aboveground storage tanks (ASTs) and underground storage tanks (USTs) in more detail. In this sector description, it will only be mentioned that corrosion of tank bottoms, walls, roofs, and roof structures can pose a danger to their structural integrity. Corrosion may cause leaks that result in loss of product or pollution of the soil and water around a tank. Of course, fuel leaks and soil pollution should be prevented, especially in a farm environment, where production depends on good soil quality.

Keeping Equipment Clean / Dry An obvious method of corrosion control is to keep equipment and machinery clean and dry after each use. Prevention of corrosion under deposits such as mud or product waste can prolong the life of machinery. Also, the exposure to bacteria, fertilizers, cleaning compounds, and sanitizing solutions should be minimized. In addition, the removal of mud will decrease the wear and possible erosion-corrosion on engines and moving components, because there is less sand between the moving parts.

Material Selection Corrosion-resistant materials can be selected for farming equipment and machinery, but the added cost of high-alloy components is often restrictive. Where possible, painted carbon steel is the primary material of choice for most machinery and equipment, because of its low cost and relative ease of maintenance. Nickel alloys are used for augers, which provide resistance to corrosion, abrasion, and wear. Stainless steel fittings are used in equipment exposed to corrosive fertilizers, or in milking equipment. Fiber-reinforced polymer storage tanks can be used for water storage or to store relatively small quantities of chemical products used for farming.

External Coatings / Paints Painting the exposed external surfaces of equipment provides corrosion protection and improved appearance. Selection of the coating type depends on the use of the equipment. External coatings must be able to withstand the effects of abrasion, weather, and ultraviolet light. Surface preparation and application of paint is an easy method to prevent or slow down the effects of corrosion. Farmers can do this work themselves, repairing aging equipment on an as-needed basis. For underground structures, such as USTs, corrosion control of the external surfaces can be achieved with a combination of cathodic protection and a dielectric coating. However, an external coating must be applied when the tank is new. A buried tank cannot be retrofitted with an external coating unless it is removed from the ground.

Internal Linings Internal corrosion protection, where required due to contamination or corrosive products in storage tanks, is commonly maintained with an internal liner, sometimes in combination with galvanic cathodic protection. Internal coatings are specified in order to prevent internal corrosion and to prolong the operation life of tanks. A specific example of internal linings is their application on mild steel fertilizer tanks. They are used primarily for corrosion protection from both fumes and condensation in the vapor space and immersion exposure to the stored liquid chemicals.

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Appendix X – Agricultural Production

Cathodic Protection Aboveground tanks that are subject to a stored liquid and that can have a contaminated water layer should be internally coated and cathodically protected on the bottom and partially along the wall. The external bottom corrosion of site-fabricated tanks (most tanks greater than 4 m in diameter) can be controlled with a combination of select sand/concrete foundation pads, impervious liners, and cathodic protection (CP). The design of CP for new or existing ASTs and USTs includes consideration of the proximity to other metallic structures and existing CP systems, the type of grounding, the estimated remaining life of the tank, the type and temperature of the stored product, the amount of product stored, the cycling rates, the method of tank bottom plate construction, the type of tank foundation, the type of secondary containment, if any, and the back-fill soil characteristics. There are two types of CP: (1) sacrificial anode CP, by zinc or magnesium ribbon or ingot anodes, and (2) impressed-current CP, using perimeter, deep-buried, angle-drilled anodes or vertical, loop, or string undertank anodes.

CORROSION MANAGEMENT The U.S. Environmental Protection Agency reports that an independent on-farm assessment program is currently being developed. The on-site assessment will include a detailed review of all production operations and waste management practices of a facility and a thorough inspection of all facilities. Some practices and conditions assessed will include the condition of water recycle lines and pumps; condition and design of flush equipment and manure piping; construction materials and age of structure; and condition and maintenance of piping, check valves, and other transfer equipment.(10) The American Petroleum Institute (API) performs annual inspections on fertilizer tanks. The inspectors visually inspect corrosion conditions, coating conditions, and welds. Before an inspection, the tank must be cleaned in order to remove hazardous gases or chemicals. A basic API inspection for a standard tank can cost approximately $3,000 to $5,000.(3) The National Electrical Code (NEC) provides minimum standards and recommended practices to ensure safety and reduce the risk of electrical system failure. The code provides proper installation procedures and equipment materials required for corrosion prevention and safety. Corrosion must be minimized in agricultural buildings because it may lead to electrical failures.

REFERENCES 1.

United States Farm Count, National Agricultural Statistics Service, www.nass.usda.gov./census/census97/congdist2/states/united_states/us.htm, November 2000.

2.

J. Schepers, University of Nebraska, Agricultural Research Service Technical Expertise Contact, Personal Communication, October 2000.

3.

D. Cope, DenCo Industrial Sales and Service, Personal Communication, October 2000.

4.

USDA National Agricultural Statistics Service, www.usda.gov/nass/aggraphs.htm, November 2000.

5.

Plumbing Systems of Agricultural Sprayers, Institute of Agriculture and Natural Resources, University of Nebraska, www.ianr.unl.edu/pubs/farmpower/g1020.htm, November 2000.

6.

R. Stowell, Department of Food and Agricultural and Biological Engineering, Personal Communication, October 2000.

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7.

United States Department of Agriculture (USDA), Agricultural Research Service, www.nps.ars.usda.gov.

8.

Vehicle Inventory and Use Survey, 1997 Economic Census, Geographic Area Series, U.S. Department of Commerce, Economics and Statistics Administration, U.S. Census Bureau, October 1999.

9.

Farm Machinery and Equipment Manufacturing, 1997 Economic Census, Manufacturing, Industry Series, U.S. Department of Commerce, Economics and Statistics Administration, U.S. Census Bureau, November 1999.

10.

Description of On-Farm Odor/ Environmental Assistance Program, Farm Environmental Assessment, U.S. Environmental Protection Agency, Office of Regulatory Enforcement, http://es.epa.gov, November 2000.

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