MISSISSIPPI'S WOOD PRODUCTS MANUFACTURING INDUSTRIES:

AN OVERVIEW REPORT ON WOOD RESIDUE DISPOSAL

Submitted To:

Jack Kennedy, Industrial Representative

Mississippi Power Company

Hattiesburg, Mississippi

Submitted By:

Paul H. Short, Ph.D.

Wood Products Specialist

Food & Fiber Center

Mississippi Cooperative Extension Service

Mississippi State University

February 19, 1993
MISSISSIPPI'S WOOD PRODUCTS MANUFACTURING INDUSTRIES:

AN OVERVIEW REPORT ON WOOD RESIDUE DISPOSAL

Mississippi's wood products manufacturing industries consist of

both primary and secondary manufacturing. The Mississippi Forestry

Commission defines primary forest products industries as those

which purchase logs and bolts as they come from the woodlands and

convert them into rough, unfinished products which can be

remanufactured into finished or semi-finished products. They

further define secondary forest products industries as industries

which purchase rough, unfinished products from primary industries

and finished or semi-finished products from other secondary

industries and remanufacture them into finished or semi-finished

products.

As with all manufacturing operations, the primary and secondary

wood products manufacturing industries generate residues. These

residues may be defined as either hazardous or non-hazardous. For

example, wood and bark are normally considered non-hazardous

materials. During the finishing operation some wood products are

finished with organic solvent-based materials, which may be

classified as hazardous materials. The combination of wood and

finish may be classified as a hazardous material. However, the

majority of Mississippi's manufactured wood products are not

finished. Thus, this report will address only non-hazardous wood

residues generated during the primary and secondary wood

manufacturing operations. This wood residue will be defined as a

non-hazardous, industrial processing by-product, and represents an

economic opportunity for the state of Mississippi.

It is to be noted that the furniture manufacturing industry, a

secondary manufacturing industry, is the largest and fastest

growing manufacturing industry in Mississippi, contributing over a

billion dollars annually to the state's economy. Decisions

concerning its wood residue disposal will affect the future of the

state's furniture industry.

This report will first briefly describe the wood residue being

generated in Mississippi. Next, it will describe some of the many

economic opportunities that exist for this residue. And lastly, it

will describe some strategies for maximizing the benefits from the

material.

For clarification, an Appendix contains calculations associated

with examples of value-added, wood residue products discussed. It

must be noted that considered costs during the discussion are for

capital investments and do not include any other costs, e.g.,

operating costs. Where assumptions where made, values were chosen

which would minimize the returns on the investments.

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The By-Products

Approximately 56 percent of Mississippi's land area, or 17

million acres, is currently forested with both softwoods and

hardwoods. Although the harvesting of timber during a logging

operation generates wood residues in the form of tree tops, sawdust

and broken timber, this biomass does not present any substantial

disposal problem. Thus, this particular type of residue will not

be discussed in this report.

During the sawing of logs at a sawmill, bark, chippable material,

and sawdust residues are generated. The factors that can be used

for estimating the tonnage of wood and bark residue generated per

thousand board feet of lumber produced by both softwood and

hardwood sawmills are found in Table 1. As an example:

(Appendix A-l)

A circular headsaw sawmill sawing oak logs with 2 inch

tops, and annually producing 1 million board feet of oak

lumber, would generate:

720 tons green bark

1,530 tons green chippable material

1,340 tons green sawdust

Although, the yield from a typical sawmill is approximately 50

percent of the initial log volume, it was estimated that in 1984

4.9 million oven-dry tons, or 8.2 million green tons, of wood

residue were generated by sawmills in Mississippi. Approximately

50 percent of the sawmill wood residues were used for boiler fuel

in 1984.

Focusing attention on the hardwood residue being generated by the

Mississippi furniture manufacturing industry, it is estimated that

the average furniture plant utilizes approximately 60 percent of

the lumber it processes. If oak lumber has an average price of

$800 per thousand board feet (MBF), a 1 percent increase in

manufacturing efficiency would save $218,500 per year for the

average plant processing 10 million board feet (MMBF) per year. It

needs to be emphasized that source reduction should be the major

method of minimizing waste (Appendix A-2). Note that a board foot

is a unit of measure; it represents a board 1 foot square and 1

inch thick. Thus, 1 BF contains 144 cubic inches of wood.

Table 2 is a list of factors for estimating tons of wood and bark

residue generated per thousand board feet of wood used to produce

various wood products. Information published by TVA indicates that

the wood residue from the upholstered furniture manufacturing

industry consists of 49 percent shavings, 42 percent chippable, and

9 percent fine material or sawdust. It is estimated that for each

MBF of high density hardwood, e.g., oak, that is processed

approximately 0.74 tons of hardwood residue is generated.

Processing a low density hardwood, e.g., yellow poplar, generates

approximately 0.53 tons of residue per MBF. A typical manufacturer

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of upholstered furniture employing 250 people will process

approximately 10 MMBF per year. Thus, this manufacturer would

generate approximately 7,400 tons of oak residue per year (Appendix

A-3). It has been estimated that for the year 1989, 200 MMBF of

lumber was processed by the furniture industry generating 148,000

tons of wood residue. This is enough residue to fill 15,000

tractor-trailer trucks which bumper-to-bumper would reach from

Tupelo, Mississippi, to beyond Memphis, Tennessee.

One plant manager of a upholstered furniture plant in Mississippi

is paying transportation costs plus $14 per ton tipping fee to

dispose of his wood residue at a municipal landfill. If this is

typical, the estimated 148,000 tons of wood residue generated

annually by the whole furniture industry would represent a cost of

$2,000,000 to the industry considering only the tipping fees. It

 interesting to note that this same 148,000 tons of wood residue

has a BTU value equivalent to approximately 65,000 tons of coal

(Appendix A-4)! A South Carolina electric utility is burning wood

residue along with coal and saving an estimated $80 per hour in

fuel costs.

Approximately 75 percent of the Mississippi Furniture

manufacturers are located in northeast Mississippi. It is

estimated that over 110,000 tons of hardwood residue generated each

year comes from this 20-county area.

Due to the high cost of disposal and the trend for these costs to

increase dramatically over the next few years, a major concern for

any wood products manufacturing plant manager is the availability

of an economical efficient method of disposal of his wood residue.

It would appear to be an attractive promotional and marketing tool

for economic development if prospective manufacturers could be

ensured that Mississippi has an economic and safe means of either

utilizing the wood residue in an innovative, value-added product,

or disposing of it.

Economic Opportunities For Wood Residue

It is believed that many furniture manufacturers are currently

disposing of their wood waste by utilizing local landfills and/or

rubbish dumps. Considering that some manufacturers are paying

tipping fees as high as $14 per ton, and that new EPA regulations

will make a large number of these landfills cost prohibitive,

manufacturers may be forced to curtail plant expansions and many

may even consider closing operations. Critical decisions

concerning wood residue disposal need to be made in a very timely

manner.

There are several alternative uses for wood residue besides

landfilling. These value-added uses need to be engineered to

specific plant sites, but should be given serious consideration.
The discussion of these alternative uses considers only the initial

capital investment costs, and does not consider any operating

costs.

Wood incineration system. Although wood incineration systems are

a means of disposing of wood residue, they do not directly increase

value added to the manufacturing plants economy. There are many

EPA approved incineration systems currently operating, especially

in the northern part of the United States. It is estimated that an

incinerator burning 1,800 pounds of wood residue per hour, 50

percent moisture content, would cost $40,000 and generate over 5

million BTUs per hour. For reference, it is estimated that a

20,000 pound per hour incinerator would cost $120,000 and generate

over 57 million BTUs per hour. It may be reasonable to include the

installation of commercial non-hazardous incineration systems with

all new regional landfill proposals to dispose of residue from

local industrial plants. These incineration systems could be

purchased jointly between counties, manufacturing plants, etc..

This approach to wood residue disposal would provide an immediate

solution the current problem.

Wood-fired boiler system. The next logical step in the sequence of

wood incineration is the use of wood residue as a fuel for boilers

which could supply thermal energy for plant heating, lumber drying

and/or processing steam. There are over 90 installations of this

type in Mississippi. An example of the potential economic

advantages of using a wood-fired boiler system to dry green lumber

is presented. To dry 1 MBF of green lumber from 50 to 6 percent

moisture content requires an estimated 4 million BTUs of energy.

A 150 HP boiler produces approximately 45 billion BTUs of energy

per year and costs approximately $150,000. Natural gas as a fuel

produces approximately 1 million BTUs of energy per 1 MCF at an

estimated cost of $3.50 per MCF. Assume that a typical furniture

plant processes 10 MMBF of lumber per year. To dry this amount of

lumber would require 40 billion BTUs per year. This would require

40,000 MCF of natural gas per year with a fuel cost of $140,000.

Thus, if the plant manager would use a wood-fired boiler system, he

would realize a substantial savings in energy costs (Appendix A-5).

Fuel for a cogeneration system. Cogeneration will be defined as

the process of producing both thermal and electrical energy with a

wood-fired boiler/turbine system. There are over 10 cogeneration

systems of this type operating in Mississippi. An example of the

economic potential of a cogeneration system is given. A 200 HP

wood-fired boiler system is the minimum size required for

cogeneration at an estimated installation cost of $1,000 per KWH of

electricity produced. A 200 HP boiler system would produce

approximately 420 KWH of electricity at an estimated cost of

$495,000. Operating at 50 percent annual capacity this system

would produce 210 KWH of electricity. Public electric utilities

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charge approximately $0.06 per KWH. For a minimum cogeneration

system of 210 KWH, the average savings in only electrical operating

costs would be approximately $110,000 per year (Appendix A-6).

Wood residue as finger jointing raw material. Currently, there are

some manufacturers finger jointing the chippable portion, or larger

pieces, of their wood residue to augment plant production. Other

potential markets would include molding, stair rails, door and

window framing, etc.

The capital investment for a finger jointing machine operating at

80 feet per minute is estimated at $225,000. If it is assumed that

a furniture plant processing 10 MMBF per year could produce and

utilize 336 MBF of finger-jointed product per year, a potential

savings of $134,000 per year in lumber cost could be realized.

This assumes a value of $400 per MBF for the finger-jointed product

(Appendix A-7).

Wood residue as raw material for particleboard manufacturing. It

is feasible for certain particleboard manufacturers to use a

maximum of 10 percent of hardwood shavings as raw material in

combination with softwood shavings. The shavings portion of

classified wood residue from a furniture manufacturing plant would

be suitable for particleboard manufacturing.

An average size particleboard plant could utilize approximately

27,000 tons of hardwood shavings per year. A furniture

manufacturer processing 10 MMBF of oak per year would produce

approximately 3,600 tons per year of suitable hardwood shavings for

particleboard manufacturing (Table 2). Most particleboard

manufacturers desire oak for the hardwood portion of their raw

material mix due to the acidic nature of oak.

Furniture manufacturers would receive approximately $10 per ton

for oak shavings delivered to the particleboard plant.

Transportation costs are estimated at $1.50 per mile. No further

processing of the hardwood shavings is necessary, thus, no major

capital investment would be required. For a 10 MMBF per year

furniture plant an estimated $36,000 per year could be expected

from the sale of hardwood shavings delivered to a particleboard

plant. Mississippi has only one particleboard plant which utilizes

hardwood shavings (Appendix A-8).

Wood residue pelletized for wood fuel. The technology for

pelletized wood residue or modified wood residue with additives,

e.g., urea, has been developed. Considering the increasing market

for pelletized wood for fuel in stoves, especially east of the

Mississippi River, stricter EPA emissions regulations for burning,

and the increasing gas and oil prices, demand for pelletized wood

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fuel is dramatically increasing. Pelletizing equipment is

estimated at $600,000 for a capacity of 7,000 tons per year.

Pelletized wood fuel is selling for $62.00 per ton, bulk, and

$91.00, bagged.

A 10 MMBF per year furniture plant produces a minimum of

approximately 7,000 tons of suitable wood residue for pelletizing

into wood fuel (Table 2). Thus, with an initial capital

investment of $600,000, it would be possible to realize an annual

return of $434,000 for bulk pellets, $637,000 for bagged pellets

(Appendix A-9). This return considers only capital investment

costs and does not include operating costs, or any other associated

costs.

Another pelletized wood residue product is compressed wood fire

place logs. The latest technology allows these logs to be made of

hardwood and/or softwood particles using only high temperature and

pressure to form the logs. The market for this type of fire place

log is increasing, especially, in the larger metropolitan areas.

Wood residue as livestock bedding material. Due to the limited

suppliers, there is a growing demand for livestock bedding.

Softwood shavings are considered to be ideal. A suitable baling

operation would require a capital investment of approximately

$26,000. An estimated selling price for a bale of wood shavings is

$3.00 per 60 pound bale with manufacturing costs of $1.50 per bale.

A 10 MMBF per year furniture plant processing poplar, a low density

hardwood, would produce an estimated 2,600 tons of suitable

shavings per year (Table 2). Producing 2,600 tons of shavings per

year a furniture manufacturer may be able to sell 87,000 bales per

year with an estimated gross profit of approximately $130,000 per

year (Appendix A-10). This gross profit does not consider

operating costs and any other expenses.

It is interesting to note that with Mississippi's large poultry

production requiring extensive amounts of bedding material, a ready

market is available for wood residue shavings. The spent bedding

from the poultry houses would be very suitable for soil additives

requiring a high nitrogen content.

There are other possibilities for utilizing wood residue in

value-added products, e.g., landscape and mulch, floor sweep,

charcoal, etc. Further processing of the larger wood residues

could generate additional amounts of smaller sized materials. For

example, grinding chippable material could produce finer, sawdust

material.

Open dumping and burning of wood residue is not an option. If a

manufacturer needs to dispose of wood residue, but does not have

the ability to utilize an existing landfill, it is possible to

establish a private wood residue dump site.

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Private wood residue dumping site. Open burning and/or dumping is

not an acceptable method of disposing of wood residue. An

acceptable method is to use or operate a private landfill. It is

not normally required that the operator of a rubbish disposal

landfill obtain a permit. However, there is an application process

in order to make that determination. To initiate this application

process, a letter of application should be filed with the

Mississippi Department of Environmental Quality (DEQ), including

the following information about the proposed operation:

1. The type, description, and characteristics of the

wastes to be accepted at the landfill and the anticipated

sources of the wastes.

2. A legal description of the site and a map showing the

boundaries, roads, designated disposal area, buffer

distances, and other physical characteristics of the

site. In addition, a property owner's map indicating the

surrounding immediately adjacent property owners to the

site.

3. The name and address of the landowner, if different

from the site operator, and written confirmation that the

landowner concurs with the use of the subject property as

a solid waste disposal facility.

4. A letter from the County Administrator or County

Board of Supervisors stating that there are no zoning

ordinances, laws or regulations which restrict or

prohibit the siting of this facility at the proposed

location.

5. A plan of operation including details regarding site

maintenance, cover frequency, equipment available, and

any other pertinent information.

6. Plan to prohibit unauthorized wastes from the

landfill, e.g., household garbage, putrescible wastes,

hazardous wastes.

7. Closure plan, e.g., final cover, grading and sloping

intentions.

Upon review of the submitted information, DEQ will conduct an

inspection of the site to determine if there are any special

characteristics or conditions that would make the site unusable or

would require a permit. Following this inspection, DEQ will

provide written authorization or denial of the rubbish landfill

operation.

According to the State Of Mississippi, Nonhazardous Waste

Management Regulations, Regulation N. PC/S-l, July 6, 1988, Section

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E--Rubbish Disposal Facility:

A rubbish disposal facility is one which receives materials.

e.g. brush, tree limbs, stumps, leaves, construction and

demolition debris, and other inert materials. A permit shall not

normally be required for a rubbish disposal facility...

However, the following minimum requirements shall apply to all

rubbish disposal sites:

1. A minimum separation distance of 150 feet shall be

maintained between the disposal operation and the site

boundary.

2. Rubbish shall not be disposed in such a manner that

may result in washout.

3. Rubbish materials shall be managed in a manner that

it shall not become windblown or harbor insects or

rodents.

4. Open burning of rubbish shall be prohibited.

5. An adequate supply of water under pressure at the

site or an adequate stockpile of earth reasonably close

to the disposal area shall be provided, or there shall be

a nearby organized fire department providing service when

called.

6. Garbage, liquids, sludges, paints, solvents,

asbestos, putrescribes, and toxic wastes and other wastes

determined to have a possible adverse effect on the

environment shall not be disposed at a rubbish site.

7. Unloading and disposal of rubbish shall be confined

to as small an area as practical.

8 . Adequate security at the site shall be established

and maintained in order to prevent uncontrolled access

and dumping.

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A-l.

From Table 1, circular headsaw, 2-inch top, hard hardwood,

g (green):

0.72 tons/MBF bark

1.53 tons/MBF chippable

1.34 tons/MBF sawdust

Calculation:

(0.72 tons/MBF) x (1 MMBF) = 720 tons green bark

(1.53 tons/MBF) x (1 MMBF) = 1,530 tons green chippable

(1.34 tons/MBF) x (1 MMBF) = 1,340 tons green sawdust

A-2.

Savings associated with an increase in yield from 60 to 61

percent for the initial breakdown of oak lumber priced at $800

per MBF. Example is for a typical furniture plant processing

10 MMBF per year.

Calculation:

Value of lumber processed at 60% efficiency:

($8OO/MBF) / (0.60) = $1,333.33/MBF

Value of lumber processed at 61% efficiency:

($8OO/MBF) / (0.61) = $1,311.48/MBF

Annual savings:

($1,333.33/MBF - $1,311.48/MBF) x 10 MMBF = $218,500

A-3 :

From Table 2, either wooden furniture frame or an upholstered

furniture plant, hard hardwood:

0.31 tons/MBF chippable material

0.36 tons/MBF shavings

0.07 tons/MBF fine (sawdust)

0.74 total tons/MBF wood residue

Calculation:

(0.74 tons/MBF) x (10 MMBF/year) = 7,400 tons/year

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A-4 :

Fuel required for equivalent heat:

Bituminous coal (80% net boiler efficiency) = 0.034 tons

Wood & bark, 30% MC (76.08% efficiency) = 0.077 tons

Calculations:

( Coal ) / (0.034 tons) = (148,000 tons) / (0.077 tons)

Equivalent coal = 65,351 tons

A-5 :

Estimation: To dry 1 MBF of lumber from 50 to 6% moisture

content requires approximately 4 million BTUs; Natural gas

produces approximately 1 million BTUs/MCF at a estimated cost

of $3.50/MCF.

Calculation:

Energy to dry 10 MMBF/year from 50 to 6% moisture

content:

(4 MMBTU/MBF) x (10 MMBF/year) = 40 MMMBTU/year

Natural gas required:

(40 MMMBTU/year) x (1 MCF/l MMBTU) = 40 MMCF

Annual fuel cost for natural gas:

(40MMCF)x($3.50/MCF) = $140,000

A-6:

Estimation: Public utilities charge $O.O6/KWH; a plant

requires an average of 210 KWH per hour for 24 hours a day.

Calculation:

(210 KHW) x ($O.O6/KWH) = $12.60/hour

(365 days/year) x (24 hours/day) = 8,750 hours/year

(8,750 hours/year) x ($12.60/hour) = $l10,376/year

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A-7:

Estimation: The yield efficiency for processing lumber is

approximately 60% (40% wood residue is generated);

approximately 42% of the wood residue generated would be

suitable for finger jointing; the manufacturing plant

utilizes only 20% of the finger-jointed material; plant

processes 10 MMBF of lumber annually.

Calculation:

(10 MMBF/year) x (0.40) = 4 MMBF/year

(4 MMBF/year) x (0.42) = 1.68 MMBF/year

(1.68 MMBF/year) x (0.20) = 336 MBF/year

(336 MBF/year) x ($4OO/MBF) = $134,40O/year

A-0 :

From Table 2, upholstered furniture plant generates 0.36

tons/MBF shavings; furniture plant processes 10 MMBF/year;

particleboard plant could utilize 27,000 tons/year shavings

paying $lO/ton FOB plant.

Calculation:

(0.36 tons/MBF) x (10 MMBF/year) = 3,600 tons/year

(3,600 tons/year) x ($lO/ton) = $36,00O/year

A-9 :

From Table 2, upholstered furniture plant generates 0.07

tons/MBF sawdust; furniture plant processes 10 MMBF/year;

bulked pellets sell for $62/tan; bagged pellets sell for

$9l/ton.

Calculation:

(0.07 tons/MBF) x (10 MMBF/year) = 7,000 tons/year

(7,000 tons/year) x ($62/tan) = $434,00O/year, bulk

(7,000 tons/year) x ($9l/ton) = $637,00O/year, bagged

A-10:

From Table 2, upholstered furniture plant, soft hardwood

(poplar) generates 0.26 tons/MBF shavings; furniture plant

processes 10 MMBF/year; $1.50/60 lbs bale profit.

Calculation:

(0.26 tons/MBF) x (10 MMBF/year) = 2,600 tons/year

(2,600 tons/year) x (2,000 lbs/ton) = 5,200,000 lbs/year

(5,200,OOO lbs/year) / (60 lbs/bale) = 86,667 bales/year

(86,667 bales/year) x ($1.50/hale) = $130,000/year

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