Effects of combustion parameters on polychlorinated dibenzodioxin and dibenzofuran homologue profiles from municipal waste and coal co-combustion

Variation in polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD and PCDF) homologue profiles from a pilot scale (0.6 MW_t, 2×10⁶ Btu/h), co-fired-fuel [densified refuse derived fuel (dRDF) and high-sulfur Illinois coal] combustion system was used to provide insights into effects of combustion parameters on PCDD and PCDF pollutant formation. A 24-run, statistically designed test matrix varied dRDF and/or coal firing rates (at a constant targeted energy release rate) along with a range of process variables including calcium hydroxide injection, hydrogen chloride (HCl) concentration, flue gas temperature, quench, and residence time such that the results would be relatable to a wide variety of combustion conditions. Statistical analysis of the molar homologue profiles enabled interpretation based on non-confounding variables. A multivariate, generalized additive model, based on transformations of the design variables, described 83% of the variation of the profiles characterized by log ratios of the homologue molar concentrations. This method identifies the operating parameters that are most significant in determining the PCDD/F homologue profiles. The model can be exercised to predict homologue profiles through input of these system-specific operating parameters. For example, both higher HCl and sulfur dioxide concentrations favor higher relative formation of the lower chlorinated PCDF homologues.     

Formation of persistent chlorinated aromatic compounds in simulated and real fly ash from iron ore sintering

Effects of carbon concentration and Cu additive in simulated fly ash (SFA) and real fly ash (RFA) on the formation of polychlorinated dibenzofurans (PCDFs), polychlorinated dibenzo-p-dioxins (PCDDs), chlorobenzenes, and polychlorinated biphenyls which were all regarded as persistent chlorinated aromatics in iron ore sintering were investigated. In the annealing process of SFA with various carbon contents, the yield of chlorinated aromatics and the I-TEQ obtained their maximum at 10 wt% carbon content. Active carbon in SFA acted as the carbon source as well as an adsorbent which led to higher production of PCDD/F in solid phase at 10 wt% carbon content. The increase of carbon content will be beneficial on the formation of 2,3,7,8-Chloro-substituted PCDF compared with 2,3,7,8-Chloro-substituted PCDD. In addition, the CuCl₂·2H₂O was a much more powerful catalyst in the formation of chlorinated aromatic compounds compared with elementary Cu, since it served as both a catalyst and a chlorine donor. However, the RFA behaved similarly with SFA with elementary Cu in the formation of chlorinated aromatic compounds. The effect of carbon content and copper additives on formation of 2,3,7,8-chloro-substituted congeners displayed similar characteristics with the tetra- to octa-PCDD/F isomers and even the total PCDD/Fs.     

De-novo formation of dioxins and furans and the memory effect in waste incineration flue gases

The formation of dioxin (polychlorinated-rho-dibenzodioxins - PCDD) and furan (polychlorinated dibenzofurans - PCDF) in waste incineration flyash in relation to temperature has been investigated in a bench scale reactor. The PCDD/PCDF released into the exhaust gases of the reactor and trapped in a condensation and vapour phase adsorption system were also determined. The concentrations of PCDD/PCDF in the flyash were analysed in detail for all congeners and isomers including the mono-, di- and tri-PCDD/PCDF. De-novo synthesis of PCDD/PCDF was clearly seen in the flyash with large changes in concentrations of PCDD/PCDF with only small changes in temperature. Exhaust gas PCDD/PCDF were detected at all temperatures, with the maximum emission occurring at a flyash temperature of 350 degrees C, where the equivalent of over 42 times the total dioxin/furan concentration of the original flyash was lost to the vapour phase per unit mass of initial flyash. Although the desorbed species were mainly the lower mono- to tri-congener group of dioxins and furans, the desorbed dioxin/furans had a considerable toxic equivalent value.     

Paper fibers as a carbon source for the de novo formation of polychlorinated dioxins and furans

The formation of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) from carbon that was produced by the pyrolysis of paper fibers and from wood charcoal was investigated experimentally. Fibers obtained from filter paper were pyrolyzed at 300° and 800°C to produce low- and high-temperature carbon samples. The two types of carbon and wood charcoal were mixed with silica (SiO₂) and trace copper oxide to produce three synthetic fly ash samples. Experiments to measure the formation of PCCDs/Fs from the three ash samples were conducted using a bench-scale reactor. The two carbon samples derived from paper fibers generated more PCDDs/Fs than was generated by the wood charcoal. The PCDDs/Fs generated by the low-temperature carbon and by the wood charcoal were dominated by the lower-chlorinated PCDFs. Such unique homologue distribution patterns are very similar to those generated by the open burning of household waste. The high-temperature carbon generated more highly chlorinated PCDDs/Fs. The effect of pyrolysis temperature on the de novo formation of PCDDs/Fs from residual carbon is discussed. Paper and paper products contained in household waste are likely to be the source of unburned carbon that contributes to high PCDD/F emissions in the open burning of household waste.     

Bench-scale studies on the simultaneous formation of PCBs and PCDD/Fs from combustion systems

The presence of endocrine disrupting chemicals (EDCs) in the environment has wide-ranging potential ecological and health impacts on animals and humans. A significant amount of experimental and theoretical work has been performed the examining formation and control of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), which account for only part of the EDCs being emitted from combustion devices. Generally accepted mechanistic theories for PCDD/F formation propose heterogeneous reactions in the cooler regions of the combustor involving gas-phase organic precursors (such as chlorobenzenes or chlorophenols), a chlorine donor [such as hydrogen chloride (HCl)], and a flyash-bound metallic catalyst (such as copper chloride). There is evidence that some other proposed EDCs, including polychlorinated biphenyls (PCBs), are formed through a similar mechanistic pathway as PCDD/Fs. In addition, there is evidence that certain important steps in the catalytic reaction between the copper catalyst and the organic precursors may suggest a common rate limiting step for the heterogeneous formation of the previously mentioned EDCs. This paper reports on a bench-scale experimental study to characterize a newly built reactor system that was built to: produce levels and distributions of PCDD/F production similar to those achieved by previous researchers; verify similar responses to changes in independent variables; examine the hypothesis that PCB formation rates exhibit trends similar to PCDD/F formation rates as reactor variables are changed; and begin to explore the dependence of PCB formation on temperature and precursor type. The reactor system has been built, and initial reactor characterization studies have been performed. Initial experiments yielded results that support the hypothesis of a similar formation mechanism of PCBs and PCDD/Fs in combustors. Initial experiments uncovered potential deficiencies with the reactor system and the experimental procedures and have suggested corrective action to improve the experimental system.     

An investigation on pollutant emissions from co-firing of RDF and coal

Pollutant emissions from co-firing of refuse derived fuel (RDF) and coal were investigated in a vortexing fluidized bed combustor (VFBC). RDF-5 was made of common municipal solid waste (MSW). CaCO₃ was injected in the combustor to absorb HCl at 850 °C. The results show that NO_x and HCl emissions increase with RDF-5 co-firing ratio. The NO_x concentration in flue gas at the bottom of the combustor is higher than that at the top. However, the trend of HCl released is reverse compared with NO_x emissions. It was found that the HCl concentration decreases with increasing the molar ratio of Ca/Cl. However, the effect of CaCO₃ addition on HCl retention is not significant when the molar ratio of Ca/Cl is higher than 5. The chlorine content in fly ash increases obviously with the molar ratio of Ca/Cl. PCDD/Fs emissions decrease slightly with an addition of CaCO₃. In this study incomplete combustion is regarded as the main cause for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) formation.     

Correlations between homologue concentrations of PCDD/Fs and toxic equivalency values in laboratory-, package boiler-, and field-scale incinerators

The toxic equivalency (TEQ) values of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) are predicted with a model based on the homologue concentrations measured from a laboratory-scale reactor (124 data points), a package boiler (61 data points), and operating municipal waste incinerators (114 data points). Regardless of the three scales and types of equipment, the different temperature profiles, sampling emissions and/or solids (fly ash), and the various chemical and physical properties of the fuels, all the PCDF plots showed highly linear correlations (R(2)>0.99). The fitting lines of the reactor and the boiler data were almost linear with slope of unity, whereas the slope of the municipal waste incinerator data was 0.86, which is caused by higher predicted values for samples with high measured TEQ. The strong correlation also implies that each of the 10 toxic PCDF congeners has a constant concentration relative to its respective total homologue concentration despite a wide range of facility types and combustion conditions. The PCDD plots showed significant scatter and poor linearity, which implies that the relative concentration of PCDD TEQ congeners is more sensitive to variations in reaction conditions than that of the PCDF congeners.     

Recent findings on the formation and decomposition of PCDD/PCDF in municipal solid waste incineration

The thermal formation of PCDD/PCDF in fly ashes of refuse incineration plants preferably in the low-temperature region of the boiler at 3002C is fully confirmed. Important parameters for the reaction of formation are the oxygen content and the water vapor in the offgas. Elemental carbon in the fly ash acts as an adsorbent to the precursor compounds. The oxidation of carbon may serve as a basis for the mechanism of PCDD/PCDF formation. Both reactions proceed by the Deacon process scheme. The catalytic action of CuCl₂ can be counteracted by the addition of NH₃.     

Effects of gaseous NH(3) and SO(2) on the concentration profiles of PCDD/F in flyash under post-combustion zone conditions

The influence of gaseous ammonia and sulphur dioxide on the formation of 2378-substituted PCDD/F on a reference flyash from a municipal waste incinerator has been investigated using a laboratory scale fixed-bed reactor. The reference flyash samples (BCR-490) was reacted under a simulated flue gas stream at temperatures of 225 and 375°C for 96h. The experiments were carried out in two series: first with simulated flue gas alone, and then with injection of NH(3) or SO(2) gas into the flue gas just before the reactor inlet. It was found that the injection of gaseous ammonia into the flue gas could decrease the concentration of both PCDD and PCDF by 34-75% from the solid phase and by 21-40% from the gas phase. Converting the results to I-TEQ values, it could reduce the total I-TEQ values of PCDD and PCDF in the sum of the flyash and exhaust flue gas by 42-75% and 24-57% respectively. The application of SO(2) led to 99% and 93% reductions in the PCDD and PCDF average congener concentrations, respectively in the solid phase. In the gas phase, the total reductions were 89% and 76% for PCDD and PCDF, respectively. Moreover, addition of SO(2) reduced the total I-TEQ value of PCDD and PCDF in the flyash and exhaust flue gas together by 60-86% and 72-82% respectively. Sulphur dioxide was more effective than ammonia in suppressing PCDD/F formation in flyash under the conditions investigated.     

Problems associated with the measurement of PCDD and PCDF emissions from waste incineration plants

Fly ash and stack gases from municipal waste and industrial incinerators in the F.R.G. have been analyzed for dioxins (PCDD and PCDF). Most of the currently used procedures of stack gas sampling for PCDD/PCDF have been compared and were found to be equally effective. Differences are found, however, in the recovery of surrogates added to the sampling train before sampling, which makes it difficult to validate the sampling procedure. The analysis for PCDD%PCDF in stack gas or fly ash samples from municipal waste incinerators can no longer be considered an analytical problem. Thirty samples of stack gas from a single (old) municipal waste incinerator showed wide variation in PCDD/PCDF emission, indicating that single measurements are not useful in characterizing a plant for average PCDD/PCDF emission. It will be extremely difficult to correlate plant operating conditions to PCDD/PCDF stack gas emissions or PCDD/PCDF fly ash concentrations, because the effects produced by changing conditions are obscured by the variations which occur in PCDD/PCDF concentrations during steady conditions. The variations found under steady conditions can be explained by the proposed mechanisms of PCDD/PCDF formation and decomposition at low temperatures catalyzed by fly ash. Incineration of hospital waste and pyrolytic reclamation of copper in cables and aluminium produced significant emission of PCDD/PCDF. A major noncombustion source of higher chlorinated PCDD/PCDF (tetra- to octa-isomers) is pentachlorophenol, a widespread preservative which contributes to the PCDD/PCDF concentrations found, for example, in sewage sludge, river sediments and house dust.     

Optimization of combustion conditions to minimize dioxin emissions

Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) may enter an incinerator with the waste, be created in poor combustion or form in post-combustion zones under certain conditions of temperature and oxygen. Tests of MSW burning plants show a wide range of emissions of PCDD and PCDF. Diagnostic tests show the relationship between combustion conditions and the emission of PCDD/DF before and after emission controls. Mixing effectiveness, tightness of control, moisture, furnace and post-furnace temperatures, and the use of lime and reduced temperatures for acid-gas control all have an effect on emissions of trace organics. Carbon monoxide (CO), oxygen, moisture and furnace temperature have been found to be closely related to PCDD/PCDF emissions. By control of temperature and/or oxygen, and the use of CO as an indicator, it is possible to find and maintain optimum combustion conditions so as to minimize dioxins and furans. Plants having acid-gas controls reduce emissions below those achieved by good combustion alone.     

High efficiency chlorine removal from polyvinyl chloride (PVC) pyrolysis with a gas–liquid fluidized bed reactor

In this research a gas–liquid fluidized bed reactor was developed for removing chlorine (Cl) from polyvinyl chloride (PVC) to favor its pyrolysis treatment. In order to efficiently remove Cl within a limited time before extensive generation of hydrocarbon products, the gas–liquid fluidized bed reactor was running at 280–320 °C, where hot N₂ was used as fluidizing gas to fluidize the molten polymer, letting the molten polymer contact well with N₂ to release Cl in form of HCl. Experimental results showed that dechlorination efficiency is mainly temperature dependent and 300 °C is a proper reaction temperature for efficient dechlorination within a limited time duration and for prevention of extensive pyrolysis; under this temperature 99.5% of Cl removal efficiency can be obtained within reaction time around 1 min after melting is completed as the flow rate of N₂ gas was set around 0.47–0.85 Nm³ kg^?1 for the molten PVC. Larger N₂ flow rate and additives in PVC would enhance HCl release but did not change the final dechlorination efficiency; and excessive N₂ flow rate should be avoided for prevention of polymer entrainment. HCl is emitted from PVC granules or scraps at the mean time they started to melt and the melting stage should be taken into consideration when design the gas–liquid fluidized bed reactor for dechlorination.     

Characterizing emissions from open burning of military food waste and ration packaging compositions

Emissions from open burning of military food waste and ration packaging compositions were characterized in response to health concerns from open burning disposal of waste, such as at military forward operating bases. Emissions from current and prototype Meals, Ready-to-Eat (MREs), and material options for their associated fiberboard packaging were quantified to assess contributions of the individual components. MREs account for 67–100% of the particulate matter (PM), volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated dibenzo-p-dioxins and -furans (PCDDs/PCDFs) emissions when burned in unison with the current fiberboard container and liner. The majority of the particles emitted from these burns are of median diameter 2.5 µm (PM_2.5). Metal emission factors were similar regardless of waste composition. Measurements of VOCs and PAHs indicate that targeted replacement of MRE components may be more effective in reducing emissions than variation of fiberboard-packaging types. Despite MRE composition variation, equivalent emission factors for PM, PAH, VOC, and PCDD/PCDF were seen. Similarly, for fiberboard packaging, composition variations exhibited essentially equivalent PM, PAH, VOC, and PCDD/PCDF emission factors amongst themselves. This study demonstrated a composition-specific analysis of waste burn emissions, assessing the impact of waste component substitution using military rations.     

Decreased PCDD/F formation when co-firing a waste fuel and biomass in a CFB boiler by addition of sulphates or municipal sewage sludge

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during waste incineration and in waste-to-energy boilers. Incomplete combustion, too short residence times at low combustion temperatures (<700 °C), incineration of electronic waste and plastic waste containing chlorine are all factors influencing the formation of PCDD/Fs in boilers. The impact of chlorine and catalysing metals (such as copper and iron) in the fuel on PCDD/F formation was studied in a 12 MW_th circulating fluidised bed (CFB) boiler. The PCDD/F concentrations in the raw gas after the convection pass of the boiler and in the fly ashes were compared. The fuel types were a so-called clean biomass with low content of chlorine, biomass with enhanced content of chlorine from supply of PVC, and solid recovered fuel (SRF) which is a waste fuel containing higher concentrations of both chlorine, and catalysing metals. The PCDD/F formation increased for the biomass with enhanced chlorine content and it was significantly reduced in the raw gas as well as in the fly ashes by injection of ammonium sulphate. A link, the alkali chloride track, is demonstrated between the level of alkali chlorides in the gas phase, the chlorine content in the deposits in the convection pass and finally the PCDD/F formation. The formation of PCDD/Fs was also significantly reduced during co-combustion of SRF with municipal sewage sludge (MSS) compared to when SRF was fired without MSS as additional fuel.     

Synthesis of hydrogarnet from molten slag and its hydrogen chloride fixation performance at high temperature

Hydrogarnet was synthesized hydrothermally below 200°C using molten slag obtained from municipal solid waste. For comparison, it was also synthesized using pure-phase CaO–Al₂O₃–SiO₂–H₂O, as reported previously. The structural and textural properties of this material were investigated using various analytical and spectroscopic techniques such as X-ray diffraction, X-ray fluorescence spectrometry, atomic absorption spectrometry (AAS), thermogravimetry/differential thermal analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. The Cl⁻ fixation ability of hydrogarnet was investigated in the temperature range 500–800°C in a fixed-bed flow reactor using a HCl concentration (1000 p.p.m.v.) similar to that of incinerator exhaust gas. Under these experimental conditions, the hydrogarnet was capable of reducing the HCl gas level to less than 1 p.p.m.v. Analysis of the spent catalyst revealed that the hydrogarnet was being transformed into wadalite and CaCl₂ at high temperatures. The elution test for chromium ions in hydrogarnet obtained from slag was also used, and it was found that chromium ions were not eluted from hydrogarnet. Received: January 27, 2001 / Accepted: October 11, 2001     

Recommended methodology for measurements of PCDD and PCDF in the nordic countries

In April 1986 the Nordic Council of Ministers recommended that the Nordic countries use a specific method for measurements of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) in flue gas emissions from waste combustion. The recommended protocol, which will be re-evaluated in a years time, includes the following.A one week registration period during which the plant is studied by continuous registration of a number of operating and emission parameters. The sampling period is included in this time.A sampling procedure based on a heated filter followed by a condenser, a bottle for the condensate and an adsorbent column. Before the sampling, at least two labelled PCDD are added to the filter.No specified analytical procedure. A labelled PCDF is added before the clean-up procedure and an injection standard before the final analysis. The laboratory is free to use any method that gives at least 25% recovery of the sampling standards and 50% recovery of the clean-up standard.Reporting requirements include homologue specific results for PCDD and PCDF containing four to eight chlorine atoms as well as isomer-specific results for the “dirty dozen”. The results should be compensated for incomplete recoveries and the factors used should be reported.     

Hydrodechlorination/detoxification of PCDDs,PCDFs, and co-PCBs in fly ash by using calcium polysulfide

Dioxins like polychlorinated dibenzo-p-dioxins (PCSDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) are mainly emitted from waste incinerators (WIs) and have become an international research focus because of its serious concerns over the adverse health effects. The detoxification of PCCDs/Fs and PCBs is very difficult because of their stable chemical structure. A significant hydrodechlorination/detoxification of polychlorinated 1-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) were achieved in fly ash by using an aqueous mixture of calcium hydroxide and sulfur. Two different fly ashes were studied: originating from municipal waste incinerator (FA1) and industrial waste incinerator (FA2). They were heated with the aqueous mixture at 150 °C for 30 or 60 min with agitation. Higher decomposition (87%) and detoxification (87.7%) of PCDD/Fs and PCBs were achieved at 150 °C with two runs; every run was for 30 min, compared to one run for 60 min. FA2 gave higher decomposition and detoxification as compared to FA1, which might be due to higher metal content that played a catalytic role to decompose and detoxify the PCDDs, PCDFs and PCBs. The decomposition and detoxification of PCDFs in fly ash was higher than PCDDs and was augmented with increasing number of chlorides on aromatic compounds. As the highly significant decomposition and detoxification of higher concentration of PCDD/Fs and PCBs were achieved in 1 hour without additive catalyst and at low temperature of 150 °C, therefore, the developed method is cost effective and most suitable to apply on commercial/industrial level. The detail results of hydrodechlorination/detoxification of PCDD, PCDFs at different conditions are described and its mechanism is discussed.     

Influences of chlorine content on emission of HCl and organic compounds in waste incineration using fluidized beds

HCl and some organic compounds are the precursors of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) in municipal solid waste incinerators. In this work, a lab-scale fluidized bed incinerator is adopted to study the relationship between the organic and the inorganic chlorine contents of artificial wastes and the emissions of HCl and organic compounds. The lower threshold limit (LTL) of chlorine content below which HCl and organic compounds are not generated is studied. Experimental results showed that organic chlorides had a greater potential to release chlorine than inorganic chlorides. The generation of organic pollutants fell, but the emissions of HCl increased with the temperature. The concentrations of chlorophenols (CPs)/chlorobenzenes (CBs) increased with chlorine contents. No LTL existed for HCl regardless of whether CaO was added. The LTL for CPs was between 0.1 and 0.3wt% of inorganic chloride, but there was none for organic sources. For CBs, the LTL was between 0.5 and 1.0wt% for inorganics at 700 and 800 degrees C, but 0.1-0.3 wt% at 700 degrees C and 0.3-0.5 wt% at 800 degrees C for organics. The production of PAHs and benzene, toluene, ethylbenzene and xylene (BTEX) was related to the surplus hydrogen ions that were not reacted with the chlorine. Adding CaO inhibited the production of HCl, CBs and CPs, but did not seriously affect PAHs and BTEX.     

Limitations for heavy metal release during thermo-chemical treatment of sewage sludge ash

Phosphate recycling from sewage sludge can be achieved by heavy metal removal from sewage sludge ash (SSA) producing a fertilizer product: mixing SSA with chloride and treating this mixture (eventually after granulation) in a rotary kiln at 1000 ± 100 °C leads to the formation of volatile heavy metal compounds that evaporate and to P-phases with high bio-availability. Due to economical and ecological reasons, it is necessary to reduce the energy consumption of this technology. Generally, fluidized bed reactors are characterized by high heat and mass transfer and thus promise the saving of energy. Therefore, a rotary reactor and a fluidized bed reactor (both laboratory-scale and operated in batch mode) are used for the treatment of granulates containing SSA and CaCl₂. Treatment temperature, residence time and - in case of the fluidized bed reactor - superficial velocity are varied between 800 and 900 °C, 10 and 30 min and 3.4 and 4.6 m s⁻¹. Cd and Pb can be removed well (>95 %) in all experiments. Cu removal ranges from 25% to 84%, for Zn 75-90% are realized. The amount of heavy metals removed increases with increasing temperature and residence time which is most pronounced for Cu.In the pellet, three major reactions occur: formation of HCl and Cl₂ from CaCl₂; diffusion and reaction of these gases with heavy metal compounds; side reactions from heavy metal compounds with matrix material. Although, heat and mass transfer are higher in the fluidized bed reactor, Pb and Zn removal is slightly better in the rotary reactor. This is due the accelerated migration of formed HCl and Cl₂ out of the pellets into the reactor atmosphere. Cu is apparently limited by the diffusion of its chloride thus the removal is higher in the fluidized bed unit.     

Determination of inorganic and organic priority pollutants in biosolids from meat processing industry

The biosolids (BS) generated in the wastewater treatment process of a meat processing plant were monitored and the priority pollutant content was characterized. The trace metal and organic pollutant content – polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDF) – were determined quantitatively and compared to guideline limits established by the US EPA and EU. PCBs were not detected in the solid samples, while trace metals, PAHs and PCDD/PCDF were detected in concentrations below the limits established by international standards. Toxic equivalent factors were evaluated for the biosolids, and the results proved that these wastes can be safely deposited on land or used in combustion/incineration plants. Since no previous data were found for meat processing waste, comparisons were made using municipal sewage sludge data reported in the literature. Since, this report monitored part of the priority pollutants established by the US EPA for meat and poultry processing wastewater and sludge, the results verified that low pollution loads are generated by the meat processing plant located in the southern part of Brazil. However, the BS generated in the treatment processes are in accordance with the limits established for waste disposal and even for soil fertilizer.