13. WASTE-TO-ENERGY
Any place, equipment, device or plant designed and/or operated to process solid or liquid waste into usable secondary materials, including fuel and energy.
13.1 INTRODUCTION
This chapter of the Douglas County Comprehensive Solid Waste Management Plan (DCCSWMP) outlines the regulatory framework overseeing Waste-to-Energy (WTE) facilities, discusses the existing conditions and programs within the Regional Planning Area (RPA), establishes objectives to meet existing and projected needs, identifies alternatives, and recommends actions for achieving the established objectives.
13.2 REGULATORY FRAMEWORK
13.2.1 Federal Requirements
Energy recovery and incinerator facilities are federally regulated under the Clean Air Act (CAA) and the Resource Conservation and Recovery Act (RCRA).
13.2.2 State Requirements
All energy recovery and incinerator regulations are administered by the Department of Ecology (DOE) under Chapter 173.304 WAC. Specifically, WAC 173.304.440 applies to all facilities designed to burn more than twelve tons of solid waste per day, except for facilities burning wood waste or gases recovered from a landfill.
13.2.3 Local Requirements
Chelan-Douglas Health District
Under Chapter 173.304 WAC the Chelan-Douglas Health District (CDHD) enforces regulations which include siting, design, operation, closure and post-closure activities of waste-to-energy facilities. In addition, the CDHD would issue solid waste facility permits, which ensure compliance with all relevant federal, state and local regulations and environmental monitoring requirements. The DOE assists in enforcement through permit review and technical assistance to the CDHD.
Douglas County
Any jurisdiction, agency, private corporation, individual or other entity wishing to import solid waste into Douglas County must conform to the Douglas County Solid Waste Importation Ordinance (DCSWIO). As specified within the ordinance, a formal Letter of Request to the Douglas County Board of Commissioners requesting that their application for solid waste importation be reviewed is required. Only after the Douglas County Board of Commissioners have received a Letter of Request, will the review and approval process begin. The Douglas County Board of Commissioners will review the information contained within the Letter of Request with county staff and others. If it is determined by the Douglas County Board of Commissioners that sufficient information has been provided, and that all known potential adverse impacts have been identified, assessed and mitigated, the request may be approved.
13.3 EXISTING CONDITIONS
13.3.1 WASTE-TO-ENERGY FACILITIES
There are currently no WTE facilities located within the RPA. The closest WTE facility to the RPA is located in Spokane and is owned by the Spokane Regional Solid Waste System and operated under contract by a private firm. The WTE facility is located on a 52-acre site approximately 1.5 miles west of the City of Spokane, on land leased from the Spokane International Airport Board. Two overhead cranes mix and sort the waste and deliver it to the two waterwall furnaces for incineration. Each furnace has a design capacity of 400 tons per day. All electricity generated by the facility, except that used for in-plant purposes, is sold to Puget Sound Energy. The ash generated by the combustion process is approximately 32% of the incoming material by weight, but only about 10% by volume.
The facility processed 297,554 tons of solid waste in 1999, resulting in 95,012 tons of ash and 10,856 tons of recovered ferrous metals. An additional 864 tons of whitegoods were retrieved from the receiving floor. The facility produced 149,569-megawatt hours of electricity in 1999, with a net revenue of $5,760,409.
13.3.2 ENERGY RECOVERY FACILITIES
There are five energy recovery facilities located within the RPA. These facilities are commonly referred to as Used Oil Collection Facilities (UOCF). All are owned and operated as public facilities. Only on-specification waste oil is collected at these facilities and it is utilized to heat the facilities during the winter months. Once the waste oil is tested, it is pumped into an outside storage tank. All off-specification waste oil is rejected on-site and returned to the generator for proper disposal. Once the system demands fuel, the waste oil is transferred to an inside heated tank where it is then combined with air and injected into the waste oil burner. The waste oil burner is located outside, so that no combustion takes place within the facility being heated. The waste oil burner heating system is basically a non-pressurized hot water system with an atmospheric vent, which provides heat and hot water. The pre-heated atomization waste oil burner cleanly burns the on-specification waste oil which in turn heats water in a stainless steel tank surrounding the combusting chamber and the heat recovery chambers. Heat is delivered to the heating units by circulating the hot water from the outside waste oil burner through hot water pipes to a heat exchanger located in the heating units. Once the hot water has circulated through the heat exchanger, it is returned to the waste oil burner, where the process is repeated.
The total on-specification waste oil storage capacity within the RPA when completed is 35,125 gallons. The Douglas County Used Oil Collection Facility is located at the county shop in Waterville. The on-specification waste oil storage capacity is 5,350 gallons. The City of East Wenatchee is served by a UOCF located at the Eastmont School District Maintenance Shop and Bus Garage. The system located at the Maintenance Shop has a storage capacity of 5,475 gallons and the Bus Garage has a storage capacity of 5,350 gallons, for a combined total of 10,825 gallons. The City of Rock Island has located its UOCF at its city shop. The on-specification waste oil storage capacity is 2,800 gallons. The Town of Mansfield is serviced by a UOCF located at the Douglas County Shop in Mansfield. The on-specification waste oil capacity is 5,350 gallons. The Town of Waterville has located its UOCF at its town shop. The on-specification waste oil capacity is 5,450 gallons. The City of Bridgeport is scheduled to have a UOCF by the fall of 2003. This UOCF will be located at the city shop. The on-specification waste oil storage capacity will be 5,350 gallons.
Map 13-1 Waste-To-Energy Facilities within the State
13.4 OBJECTIVES
13.4.1 Ensure that Waste-to-Energy Technologies are Reliable and Cost Effective
WTE facilities do not have long operational histories. Early plants were plagued with frequent shutdowns, explosions, equipment failures and high maintenance costs. Because of these past problems, most modern facilities have undergone major design and equipment modifications. Operational problems now associated with these facilities center around unproven new technologies and the complexity of material processing.
13.4.2 Ensure that an Adequate Waste Stream Exists to Justify the Cost of Implementing and Sustaining a Waste-To-Energy Facility
Any WTE processing technology that is considered should be economically feasible and designed to fit the specific needs of the RPA. Emphasis should be placed on developing a system that is sustainable and consistent with the waste stream composition of the RPA. Any expansion of the system to include outside sources of waste, though improving the economic feasibility of implementing and sustaining the system would be dependant upon conditions and sources that are outside the control of the RPA.
13.4.3 Ensure that A Waste-to-Energy Facility Conforms with all Federal, State, and Local Regulations
All alternatives must meet all Federal, State and local regulations, including all local land use, zoning and building requirements, guidelines and standards.
13.4.4 Ensure that Proper Pollution Controls for Emissions and Ash Management are Addressed
Any WTE facility would be required to continually meet all Federal, State and local air quality standards. Changes to the waste stream composition could have an effect upon air emissions and residual ash. Residual ash, both bottom ash and fly ash, is subject to RCRA Subtitle C regulations, which govern the management of hazardous waste.
13.5 ALTERNATIVES
13.5.1 Conduct a Waste-to-Energy Feasibility Study
Economic Feasibility
Based upon a 1990 consultant's evaluation of the cost-effectiveness of operating a WTE facility within the RPA, it appears that without substantial outside funding, the operation and maintenance cost of a WTE facility was no more economically attractive than landfilling at the GWRLF. Economic factors that will affect the future feasibility of a WTE facility include the:
- siting and permitting costs for such a facility;
- capital expenditure needed to build such a facility;
- annual operation and maintenance costs of such a facility;
- tipping fee revenues that may be realized by the importation of wastes;
- revenues that may be realized by the sale of recovered materials;
- revenues that may be realized from the sale of energy produced.
As is common with the implementing of any sophisticated technology, cost overruns are likely and represent a potential financial risk to the participating jurisdictions. Changing energy or product markets could affect facility revenues by decreasing the value of the end-product or by causing a surplus of wastes which must be landfilled or direct hauled at additional costs. Special transport and disposal requirements for some facility wastes (i.e., compost containing toxic levels of contaminants, special incinerator ash) could also potentially add to facility costs.
Technical Feasiblity
Incineration of solid waste would require that the WTE facility continually meet local air quality standards. Changes in the incoming waste stream as a result of waste reduction and recycling programs or a change in waste handling contracts, might cause the facility to lose efficiency or decrease product production. All of these situations could prevent the processing technology from being a reliable waste disposal option or energy/product source. A factor specific to WTE facilities is the potential impact of recycling on the Btu value of the waste. Table 13-1 presents the heating value of the various components of the typical mixed municipal waste stream. The range of Btu per pound of waste that is expected with recycling implementation is estimated to vary between 4,000 and 5,200.
Table 13-1. Average Heating Value of the Solid Waste Stream in Central Washington.
|
Waste Stream Category |
Heating Value* [Btu/lb] |
Weighted Average [Btu/lb] |
|
Glass |
|
|
|
Refillable Bottles |
90 |
0 |
|
Other Recyclable Containers |
90 |
2 |
|
Non-Recyclable Glass |
90 |
2 |
|
Paper |
|
|
|
Newsprint |
6,300 |
179 |
|
Corrugated Containers |
6,400 |
385 |
|
High-Grade Paper |
5,700 |
35 |
|
Mixed Waste Paper |
5,700 |
671 |
|
Metals |
|
|
|
Aluminum Cans & Containers |
760 |
3 |
|
Tin Cans |
760 |
9 |
|
Ferrous & Non-Ferrous Scrap |
760 |
35 |
|
Other Metals |
760 |
31 |
|
Lead Batteries |
760 |
2 |
|
Plastics |
|
|
|
PET Bottles |
12,000 |
22 |
|
HDPE Bottles |
12,000 |
25 |
|
Other Plastic Products |
12,000 |
647 |
|
Textiles |
3,400 |
136 |
|
Organics |
|
|
|
Food Waste |
3,400 |
234 |
|
Yard Waste |
4,200 |
980 |
|
Wood Waste |
7,100 |
736 |
|
All Other Wastes |
3,400 |
464 |
|
TOTAL |
|
4,597 |
|
|
|
|
* Estimates based on average "as received" condition, with moisture, using the Boje equation
13.5.2 Site a Waste-to-Energy Facility within the RPA
If warranted by the feasibility study, a WTE facility could be sited within the RPA to provide another source of power to residents and businesses, while at the same time alleviating much of the Municipal Solid Waste (MSW) within the RPA. Solid Waste could be imported from other counties to be burned in the WTE facility for a fee, and the power generated by the WTE facility could be sold, thus producing a potentially profitable situation. Additionally, the Greater Wenatchee Regional Landfill (GWRLF), upon reaching capacity, could transport its MSW to the WTE facility rather than choosing to export the MSW out of the RPA.
13.6 RECOMMENDATIONS
13.6.1 Conduct a Waste-to-Energy Feasibility Study