Owners and operators of waste-to-energy (WTE) facilities have a keen interest in the performance of their facilities since it drives the overall success and cost effectiveness of their projects. There are a number of parameters that are commonly used to gauge the performance of a WTE facility and, in many cases, the contract operator. This paper compares historical data from a number of mass burn WTE facilities to establish benchmarks for various performance criteria. This paper also discusses how these benchmarks compare with performance standards that were used as the basis of design for the existing generation of mass burn WTE facilities and operating contracts and discusses how to set performance expectation levels for new projects.

An on-line cleaning technique perfected in Europe, which places low-yield explosive charges in close proximity to tube lane pluggage, and uses pre- and post-cleaning video camera surveillance to document results, has been tested at three WTE facilities in the western U.S. operated by Covanta. Testing indicates several tangible benefits relative to the more traditional off-line blasting, water washing (on-line and off-line), and stick blasting (on-line), including: • substantial elimination of cleaning related downtime between maintenance outages; • longer runtimes with less overall fouling and pluggage related ailments; • reduced off-line cleaning time at the beginning of major outages to the benefit of the outage schedule; • exemplary safety of the on-line cleaning process; • less wear and tear on pressure parts and boiler casings; and, • almost no fugitive dust problems in the boiler house that may occur with off-line blasting. The process starts with an initial video survey of fouling conditions. A water-cooled camera with purge air and temperature monitoring is inserted into the flue gas to record the fouling condition of the boiler. Following the survey, a cleaning plan is developed. Shots consist of low-yield detonating cord encased in thin gage aluminum alloy tubing. The charges are positioned in the gas lanes between tubes while being cooled with a water-air mixture and detonated. Following the cleaning effort, a final camera survey is done to verify the cleaning effectiveness, and to follow up with touch-up cleaning if necessary.

Tremendous money is wasted due to the lack of attention to the water gauge and flue plate stiffeners, and their impact on the insulation and lagging design. The design and installation of an insulation and lagging system will depend heavily upon the flue or duct stiffener arrangement. The stiffener arrangement is determined by many factors including the water gauge of the flue or duct plate design. The stiffener pattern and size is the first thing you consider when designing an insulation and lagging system. Therefore, it is imperative to understand how the size, shape and pattern of the external stiffeners are developed. The stiffener sizing of yesterday was based on a much lower water gauge pressure and allowed the insulation to be placed between the stiffeners without having to cut-to-fit. The stiffeners being designed today are quite large and much farther apart. This is due in part to the water gauge number being used in the design calculations and because they have not considered the required insulation thickness and application. A well designed and installed insulation and lagging system will save money and energy at a rate that is essential for an efficient plant operation. This is especially true when adding a selective catalytic reduction system (SCR) or a selective non catalytic reduction system (SNCR) to the back end of a steam-generating unit. The insulation and lagging system is critical for these air pollution systems to operate correctly.

Why is the detection of radioactive sources important to the solid waste industry? : Radioactive material is used extensively in the United States in research, medicine, education, and industry for the benefit of society (e.g. smoke detectors, industrial process gauges, medical diagnosis/treatment). Generally speaking, the Nuclear Regulatory Commission and state governments regulate the use and disposal of radioactive materials. Licensed radioactive waste disposal facilities receive the bulk of the waste generated in the United States with exceptions for low-level waste (e.g. medical patient waste) that may be disposed of as municipal waste. According to the Conference of Radiation Control Program Directors, Inc (CRCPD)., there has been an increasing number of incidence involving the detection of prohibited radioactive wastes at solid waste management facilities. While the CRCPD acknowledges that the increased incidence may be partially attributed to the growing number of solid waste facilities that have detection systems, undetected sources of ionizing radiation can harm the environment, have a negative impact on employee health and safety, and result in significant remedial actions. Implementing an effective detection/response plan can aid in the proper management of radioactive waste and serve to minimize the potential for negative outcomes.