Читать книгу Continuous Emission Monitoring - James A. Jahnke - Страница 35

EPA regulations concerning sludge management programs are found under Title 40 Subchapter O – Sewage Sludge and Part 501: State Sludge Management Program Regulations. Regulatory authority is given under the Clean Water Act, which requires that states must develop sludge management programs. Part 501 specifies the requirements that a State program must meet for it to be approved by EPA. Sewage sludge can be disposed of in a solid waste landfill, applied to the land, or incinerated. For landfill or land applications, limits for metal concentrations, loading levels, and pathogen density are specified.

Monitoring requirements for incineration of sewage sludge are given in Subpart E of 40 CFR 503 – Standards for the Use or Disposal of Sewage Sludge If the sludge is incinerated, the concern shifts from releases to the soil and groundwater to the efficiency of combustion and releases to the air. Total hydrocarbons are required to be monitored as specified in §503.45(a)(1) of the Code. In addition, the carbon monoxide concentration must be monitored as an indicator of combustion efficiency, where a limit of 100 ppm corrected to 7% O₂ and zero percent moisture is specified. Total hydrocarbon concentration is similarly limited to 100 ppm corrected to 7% O₂ and zero percent moisture. Accordingly, an oxygen concentration monitor and an instrument used to determine the moisture content must also be installed to monitor the stack exit gas continuously along with the THC and CO analyzers. No other requirements are given for the monitoring system and analyzers, other than that a calibration and maintenance logbook shall be retained [40 CFR 503.47(n)]. Design and operational requirements are specified for the total hydrocarbon analyzer, where it must use a flame ionization detector (FID), be calibrated with propane, and have a heated sampling line maintained at a temperature of 150 °C.

New sewage sludge incinerators are also regulated under New Source Performance Standard Subpart O if the incinerator was constructed after 11 June 1973. The regulation requires the installation of an oxygen analyzer only. Here, the instrument specifications require a ±5% relative accuracy as certified by the manufacturer and a calibration every 24 hours according to manufacturer procedures. No reference is made to the Part 60 Appendix B or Appendix F CEM requirements, which are more complete.