Grate Incinerator Research Articles

Novel and innovative pyrolysis and gasification technologies for energy efficient and environmentally sound MSW disposal

Within the context of European Union (EU) energy policy and sustainibility in waste management, recent EU regulations demand energy efficient and environmentally sound disposal methods of Municipal Solid Waste (MSW). Currently, landfill with its many drawbacks is the preferred option in the EU and many other industrialised countries. Within the waste management hierarchy thermal disposal especially incineration is a viable and proven alternative. But, the dominating method, mass-burn grate incineration has drawbacks as well particularly hazardous emissions and harmful process residues. In recent years, pyrolysis and gasification technologies have emerged to address these issues and improve the energy output. To keep the many players in the field comprehensively informed and up-to-date, novel and innovative technology approaches emphasising European developments are reviewed.

206 低空気比高温燃焼型ストーカ式焼却炉の燃焼特性

206 低空気比高温燃焼型ストーカ式焼却炉の燃焼特性

B109 The action of primary air regulation and its distribution in the low heating value waste pusher type grate incinerator

B109 The action of primary air regulation and its distribution in the low heating value waste pusher type grate incinerator

Co-combustion of shredder residues and municipal solid waste in a Swedish municipal solid waste incinerator.

Incinerating automotive shredder residue (ASR) in order to increase the recovery from end of life vehicles (ELVs) is an attractive option when recycling this material. In this study, incineration combined with energy recovery, was investigated. The incineration experiments, where 20% shredder residue (SR) was burnt with conventional municipal solid waste (MSW), were conducted in a full-scale MSW horizontal grate incinerator. Measurements were made before, during and after the incineration. The results showed some minor increases in the emission levels of raw gases sampled after an electrostatic filter, but almost no significant differences when sampled after a wet scrubber. An increased level of 'non-toxic' metals was detected within the bottom ash. It was concluded that refined SR, in small quantities, is suitable to add to MSW.

Investigation of Channel Formation Due to Random Packing in a Burning Waste Bed

Obtaining energy from sustainable sources such as waste and biomass has required a significant extension of combustion technology. Many of the advanced technologies are based on thermal treatment in gas-solid packed-bed systems such as gasifiers, incinerators and biomass furnaces. In this paper channel formation in a packed bed of fuel solids as a result of the random packing process has been investigated. Channelling causes a severely uneven distribution of the primary airflow through a packed fuel bed and results in poor combustion performance of the furnace. By assuming Furnas packing, a general relationship is derived between the bed porosity and the particle size distribution and the proposed methodology is tested against limited experimental data. A probability density function (PDF) of truncated Gaussian type is assumed for the random size distribution at local areas within the bed and the local bed porosity is calculated accordingly. Then by solving the fluid flow equations through the porous bed, flow rate profiles are obtained at the top surface of the bed. Two particulate systems were investigated as a function of change in bed height and pressure drop through the grate. Depending on bed height and pressure drop through the grate, maximum local flow rate at the top surface of the bed can be 1.5 ∼ 2 times higher than the minimum flow rate for the particulate system with a narrower size range (2.5 mm–18 mm) while the ratio of the maximum to minimum flow rate can reach as high as 8 ∼ 32 for the particulate system with a wider size range (0.677 mm–20 mm). Visualization of the velocity profile inside the bed reveals that flow passages are slightly curved in some areas but straight in others. The largest channel observed presents a ‘perfect’ straight passage of airflow running from the very bottom of the bed to the very top of the bed. Channelling inside a burning bed of solid waste in a large-scale travelling grate incinerator plant was also investigated using a unique in-house prototype instrument. The result shows that the combustion processes within the bed were dominated largely by the circles of formation and subsequent collapse of channels.

Development of an Incinerator Bed Model for Municipal Solid Waste Incineration

The growing awareness and concern over environmental problems associated with landfill has led to increased demand for incinerators to dispose of municipal waste. The design of an efficient incinerator requires fundamental knowledge of grate combustion and grate mixing, but for such a complex combustion problem, there has been no satisfactory model of the system as a whole. An experimental fixed bed reactor was used to investigate the incineration of simulated waste. Measurements of temperatures and gas compositions were made at several positions within the refuse bed. A mathematical model for combustion of the solid waste in a travelling grate incinerator was developed based on an unsteady-state static bed model. The predictions from the model were investigated and compared to the combustion experimental data carried out in the batch fixed bed incinerator. Although several simplifying assumptions were made during the model development, the final functional form of the predicted data corresponds relatively well with the measured data.

99/00608 Study of ashes from municipal wastes incinerated in classical grate boilers and FBC units—solidification of MWIR with FBC coal ashes for disposal

FBC is now widely used to burn low quality coals because of its ability to meet environmental regulations, especially where SO{sub 2} emissions are of concern. The technology is also promising for a number of other fuels, especially those having high chloride contents. The characteristics of any fuel depend strongly on the combustion technique and temperature. Thus, FBC ashes would be expected to be substantially different from grate incinerator ashes. This study looks at the characteristics of ashes (MWIR) from municipal wastes, originated from various cities in Europe, and incinerated in FBC and classical grate furnace facilities. Information is also provided on the heavy metal contents and leaching characteristics of the various MWI residues. All the results are examined in light of possible utilization strategies and landfill regulations regarding the potential for co-disposal of incinerator ashes with coal derived residues from FBC boilers to render the monoliths inert and resistant against hazardous events that may occur during ultimated and definitive storage.

Incinerator Impacts on Residential Property Sales: Beyond Price Effects

Municipal waste incinerators are commonly believed to affect residential property sales. In cases where property sales prices are not affected, sales of affected properties may increase because impact‐sensitive households can sell properties at full market value, and therefore do not incur monetary losses by moving. Alternatively, sellers can get full market prices if they are prepared to wait longer for buyers who are less sensitive or uninformed and who are therefore less likely to discount their offers due to facility impacts. Therefore, the absence of price depreciation is predicted to lead either to increased turnover or to longer time on the market to sell residential properties in the impact field of the incinerator. As a result, neighborhood stability may be affected. The predictions are tested with sales data from a rural host community with a modern mass‐burning grate incinerator where no significant sales price depreciation is found. Significant increases in property sales or resales do not occur and distance to the facility correlates very weakly with decreasing time to sell. The incinerator has only a moderate effect on residential real estate sales, and therefore does not cause destabilization of the community. This conclusion does not mean, however, that the residents do not experience losses as a result of bearing the incinerator impacts. Rather, the findings indicate that residents tend to stay and adapt to the facility.

揺動火格子式ごみ焼却炉のごみの燃焼過程モデル

揺動火格子式ごみ焼却炉のごみの燃焼過程モデル

The Control of the Refuse Incineration Plant

The present waste treatment (especially manicipal rebuse treatment) cannot rely only on national purifying, as the result, needs treatment cotrol being considered the enviromental pollution control.Incineration in Japan has been used for the above treatment, and it has been considered as the best procedure from the sight of decrease of volume, and stability of nature.The treatment and disposal procedure of waste in Japan consists 75% of incineration, 45% of land fill, 2. 5% of composting and 7. 6 of domestic treatment.The report has dealt with the procedure and condition of the incineration plant.The property of ash depends upon the incicinerator condition.The ignition loss shows about 10-15% (the standard ignition loss is less 15%), and it shows 8-20% at the continuous firing. The dust concentration by thc air pollution control restrains less 0.2g/Nm3 when the effluent gas volume is than 40, 000 Nm3/ hr., and 0.7g/Nm3 when less 40, 000 Nm3/hr.Generally, at the fixed grate incinerator the above concetration keeps less o. 7g/ Nm3 with the M. C., and at the most continuous incinerators, it keeps less 0.1.-0.2 g/Nm3 with E. P.The report added the description of toxious gasses and heavy metals.