Environmental monitoring studies

Studies of environmental monitoring of the levels of dioxins and furans, PCBs and heavy metals in close areas to the integral valorization center of Maresme (in catalan):

Medical studies


In 1995 the Maresme Consortium for Municipal Solid Waste Treatment, in conjunction with Mataró Hospital, started a pioneering study to evaluate the possible effects on the population of Mataró of the Maresme Integral Centre for Waste Recovery becoming operational. Given the scientific interest in the study, there was an agreement to carry out time-based monitoring of the evolution of the different public health indicators considered in the study, structured in three phases during a period of approximately two years.

The study group is considered in all the phases to be a group which is exposed to the plant in Mataró (inhabitants who live between 500m and 1500m from the plant), a control group in Mataró (inhabitants who live between 3000m and 4000m from the plant), and a group of workers at the plant, adding at the third phase a control group of inhabitants from Arenys de Mar.

Since then, the studies have been carried out in different waves. Since 2006, and coinciding with the sixth phase, the study has been undertaken by the Health Foundation at the Maresme Health Consortium, which continues doing the work to this day. The eighth phase of the study began in 2014, and in December 2015 the results were presented, coinciding with the 20th anniversary of the beginning of the continuous monitoring.

Specifically, the study biologically monitors the levels of dioxins (PCDD), furans (PCDF), polychlorinated biphenyls (PCBs) and heavy metals ​​(Pb, Cd, Cr, Hg, Ni, As), and is run by a multidisciplinary medical team with doctors, analysts and nurses from the Investigation Unit at the Health Foundation, the dioxin laboratory of the CSIC and the National Centre for Working Conditions in Barcelona.

The medical studies carried out since 1995 continually show that the level of dioxins and furans in the blood samples and breast milk of the study groups are comparable, and/or are in the lower range in relation to those observed in other industrialized countries. Therefore, it is medically shown that exposure to the incineration plant is not a risk factor for having higher levels of the different analysed substances.

To download the conclusions of the latest wave of studies carried out by the Investigation Unit at the Maresme Health Consortium click on the following links:

Compliance with the current legislation

The process taking place in the Centre Integral de Valorització de Residus del Maresme ensures a truly environmentally and human health friendly treatment of the waste.

Both the MBT plant and the Waste-to-Energy plant, through their corresponding environmental authorization respectively, comply with all the legal requirements set by the relevant authorities.

Regarding the recovery of energy, the Directive 2000/76/CE, of 4th December, concerning the incineration of waste, sets the environmental requirements and limits the emissions for this activity. The new Directive of Industrial Emissions adds some modifications to this regulation and strengthens the role of the Best Available Techniques (BAT).

The conversion of Directive 2000/76 / EC was in Spain RD 653/2003, of May 30, on waste incineration. This has been repealed by RD 815/2013, of October 18, which approves the Regulation of industrial emissions and development of Law 16/2002, of July 1, on integrated pollution prevention and control.

All the emissions come to be measured continuously, keeping the periodical measurements only for heavy metals (except for Hg, measured continuously) and dioxins and furans.

Regarding the emissions of dioxins and furans, the limit is 0.1 ng/Nm3. The Catalan plants not only comply with this limit, but also have real emissions, since years before the enforcement of the new limits (December 2005), much below this value (usually between 10 and 100 times below).

Information on the emissions can be found in the section “Analytical results” in the webpage menu.

In addition to the comprehensive control of the emissions, an independent accredited laboratory carries out a daily control of the immissions –ambiental air from two control stations located near the plant.

This way, the strict gas depuration systems in the Centre show they are entirely effective towards the achievement of the legal environmental quality levels –emissions and immissions– without any technical problems.

Since 1995 to present, the Waste-to-Energy plant in Mataró has gone through eight stages in the biological monitorization study called “Evolució dels nivells de dioxines (PCDD), furans (PCDF), policlorats bifenils (PCB) i metalls pesants (Pb, Cd, Cr, Hg, Ni, As) a les poblacions de Mataró i Arenys de Mar” (“Evolution of the levels of dioxins (PCDD, furans (PCDF), polychlorinated biphenyls (PCB) and heavy metals (Pb, Cd, Cr, Hg, Ni, As) in the towns of Mataró and Arenys de Mar”), carried out by the Unitat de Recerca del Consorci Sanitari del Maresme (Research Unit of the Maresme Health Consortium).
From phase VI of the study, controls were also incorporated into the breast milk of women from Mataró.

The results of the different population groups studied (exposed, control and workers of the Waste-to-Energy plant) show that there is no relationship between the concentration of pollutants and the proximity to the Waste-to-Energy plant.

In addition to the continuity of the biological monitoring study that the Consortium started in 1995, for phase VI of this study and to date, the Mataró incinerator has carried out three phases of the environmental monitoring study “Evolution of dioxin levels ( PCDD), furans (PCDF), polychlorinated biphenyls (PCB) and heavy metals (Pb, Cd, Cr, Hg, Ni, As) to the populations of Mataró and Arenys de Mar, and Evaluation of the risks to the health of the population , derived from the exhibition of the activity of the plant “, prepared by the company LABSAME SL (new name of the company TecnITox Solutions S.L. attached to the Rovira y Virgili University).

The results of the various phases show the absence of significant risks to public health derived from the operation of the facility.

Improvements in the Waste-to-Energy Plant

Compliance with the Directive 2000/76/CE

With the approval of the Directive 2000/76/CE, of 4th December, concerning the waste incineration, the requirements applicable to this activity within the waste management field for the EU were established. This Directive represented the introduction of significant changes with respect to the previous regulations, since it meant an important reduction of the limits of gas emissions, as well as a more accurate control of them by means of the continuous measurement of several of them, which was only to be periodical with the previous legislation.

Despite overly complying with the previous regulations concerning waste incineration, the new provisions coming into effect with the Directive 2000/76/CE made it necessary to plan for the future in order to ensure the adequacy of the facilities to the new legal frame.

Thus, financial help from the Cohesion Fund was requested in a joint project of adaptation of all the Catalan Waste-to-Energy facilities to the Directive 2000/76/CE.

The actions carried out in 2004-05 with the aim to ensure compliance with the Directive 2000/76/CE were:

• Implementation of a new system to reduce NOx (nitrogen oxide) based on a system of selective non-catalytic reduction (SNCR) with urea injection in the combustion chamber. The system consists of a sole storage tank of 45% urea, transport to the combustion chamber of each of the two lines, and a multilevel injection through several injecting spears into the points of the chamber which have the optimal conditions for the reduction reaction.

• Replacement of the electrostatic filters by fabric filters. These consist of two blocks of fabric filters with several compartments, to filter accurately the 70,000 Nm3/h of gas resulting from the combustion by line. In addition to the filtering effect, the filters act as chambers of post-reaction for the additives used in the treatment (lime and active carbon) since these are trapped in the fabric until they are consumed. The filters also have a pneumatic system of recirculation of the ashes in order to optimize the consumption of the additives contained.

• Incorporation of a contact reactor. It works with dry lime and it is placed between the neutralization reactor (which works with hydrated lime slurry) and the new fabric filters. This way, the best possible performance in the treatment of the acid gas is achieved, ensuring the compliance with the new limits on emissions.

• Modification of the active carbon injection system and implementation of a new silo for storing carbon.

• Implementation of new systems for measuring the gas emissions through the chimney in order to have the measurement results in a continuous way for the following pollutants: total particles, CO, HCl (same as to date); HF, COT, SO2 and NOx (new continuous measurements required by the Directive).

With the new infrastructures in the new Centre, work has been done to adapt and improve several aspects of the Waste-to-Energy plant. The actions carried out between 2010 and 2011 have been:

– Improvements in the combustion control system: new combustion control system FuzzEvent, installation of a thermal camera per line to see the combustion on the grate, installation of two pirometers IR per line to optimize the combustion process.

– Improvements in the boilers: installation of new refractory lining on the walls, new Inconel 625 cover of the boiler tubes, new tubes cleaning system.

– Improvements in the depuration system: implementation of a catalitic system for the reduction of NOx emission (SCR). The SCR system works with the previous injection of ammonia (NH3) as a reducing agent on the gas flow which then goes through a reactor containing catalyst blocks. Its efficiency reaches close to 95%. The old non catalytic system equipment is kept (SNCR) as back up when the new system needs to be stopped for maintenance.

– Improvements in the emission control system: installation of new multigas analyzers FTIR at the exit of each line’s boilers, installation of a new mercury (Hg) analyzer per line, installation of new multigas analyzers FT+FID integrated at the exit of each line’s chimneys.

Analytic results

According to the transparency policy the Consorci has always followed, in this section you will find updated information on the gas emissions of the Centre.