Environmental monitoring studies

Studies of environmental monitoring of the levels of dioxins and furans, PCBs and heavy metals in areas close to the Maresme Integral Centre for Waste Recovery (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 that takes place at the Maresme Integral Centre for Waste Recovery guarantees waste treatment that is entirely respectful of the environment and public health.

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

With regard to energy recovery, Directive 2000/76/EC of 4 December 2000 on the incineration of waste establishes the environmental requirements and maximum emission limits for this activity. The new Industrial Emissions Directive incorporates some modifications to this regulation, reinforcing the role of Best Available Techniques (BAT).
The transposition of Directive 2000/76/EC materialised in Spain in Royal Decree 653/2003, of 30 May, on waste incineration. This has been repealed by Royal Decree 815/2013, of 18 October, approving the Regulation on industrial emissions and development of Law 16/2002, of 1 July, on integrated pollution prevention and control.

Emissions are measured continuously, maintaining periodic measurements only for heavy metals (except continuous Hg) and dioxins and furans.

For dioxin and furan emissions, the limit is 0.1 ng/Nm3. Catalan plants not only comply with this limit, but their actual emissions have been well below this value for years before the new limits came into force (December 2005) (usually between 10 and 100 times lower).

Emissions can be consulted in the “Analytical results” section of the website directory.

In addition to the exhaustive control of emissions, daily monitoring of ambient air emissions is carried out by a certified external laboratory at two monitoring stations located close to the plant.

Thus, the strict gas purification systems in place at the Centre prove to be totally effective in achieving the legally established levels of environmental quality, emissions and immissions without any technical difficulties.

From 1995 to the present day, eight phases of the biological monitoring study “Evolution of the levels of dioxins (PCDD), furans (PCDF), polychlorinated biphenyls (PCB) and heavy metals (Pb, Cd, Cr, Hg, Ni, As) in the populations of Mataró and Arenys de Mar” have been carried out at the Mataró incinerator, prepared by the Search Unit of the Maresme Health Consortium. From phase VI of the study, controls in breast milk of women from Mataró were also incorporated.
The results of the different population groups studied (exposed, controls and incinerator workers) show that there is no relationship between pollutant concentrations and proximity to the incinerator.

In addition to the continuity of the biological monitoring study initiated by the Consortium in 1995, for phase VI of this study and up to the present time, three phases of the environmental monitoring study “Evolution of dioxin levels (PCDD), furans (PCDF), polycyclic dioxins (PCDF), polycyclic furans (PCDF) and polycyclic furans (PCDF)” have been carried out at the Mataró incinerator, furans (PCDF), polychlorinated biphenyls (PCB) and heavy metals (Pb, Cd, Cr, Hg, Ni, As) in the populations of Mataró and Arenys de Mar, and Evaluation of the risks for the health of the population, derived from the exposure of the activity of the plant”, carried out by the company LABSAME S. L. (new name of the company TecnITox Solutions S.L. attached to the Rovira i Virgili University).

The results of the various phases show that there are no significant risks to public health arising from the operation of the facility.

Improvements to the Energy Recovery Plant

Adaptation to Directive 2000/76/EC

With the approval of Directive 2000/76/EC, of 4th December, on waste incineration, the requirements applicable to this waste management activity were established at European Union level. This Directive presented substantial changes with respect to the previous regulation, since it implied a significant reduction in the limits for emissions into the atmosphere, as well as a more exhaustive control by means of continuous measures of several emissions contemplated in the previous legal framework as periodic.

Despite the fact that the facility was largely compliant with the previous incineration regulations, the entry into force of the requirements set out in Directive 2000/76/EC meant that a forward-looking approach was needed to ensure compliance with the new legal framework.

Cohesion Fund assistance was therefore requested for a joint project to bring all Catalan waste incineration facilities into line with Directive 2000/76/EC.

The actions carried out in 2004-2005 with the aim of ensuring full compliance with Directive 2000/76/EC were:

– Implementation of a new system for NOx (nitrogen oxides) reduction based on a selective non-catalytic reduction system (SNCR) with urea injection into the combustion chamber. The system consists of a single 45% urea storage tank, a transport to the combustion chamber of each of the two lines and a multilevel injection by means of several injector lances at those points in the chamber with optimal conditions for the reduction reaction.

– Replacement of the electrostatic precipitators by hose filters. Two multi-compartment hose filter blocks are used to filter the 70,000 Nm3/h per line of combustion gases with high efficiency. In addition to the filtering effect, the filters act as a post-reaction chamber for the additives used in the purification process (lime and active carbon), as these are retained in the hoses until they are consumed. The filters also incorporate a pneumatic ash recirculation system to optimise the consumption of the additives contained.

– Incorporation of a contact reactor. This is a contact reactor with dry lime incorporated between the neutralisation reactor with lime slurry and the new hose filters. In this way, optimum performance is achieved in the scrubbing of acid gases to ensure compliance with the new emission limits.

– Modification of the activated carbon injection system and implementation of a new carbon storage silo.

– Implementation of new systems for measuring gaseous emissions per chimney to provide continuous measurements of the following pollutants: total particulates, CO, HCl (as previously); HF, TOC, SO2 and NOx (continuous measurements incorporated by the Directive).

As a result of the new infrastructures of the new Centre, work has been carried out to adapt and improve different aspects of the Energy Recovery Plant (ERP). The actions carried out between 2010 and 2011 were as follows:

Improvements to the combustion control system: new FuzzEvent combustion control system, installation of a thermal camera per line to visualise combustion inside the grate, installation of two IR pyrometers per line to optimise the combustion process.

Boiler improvements: installation of a new refractory lining of the walls, new lining of the boiler tubes with Inconel 625, new tube cleaning system.

Improvements to the purification system: installation of a catalytic system for the reduction of NOx emissions (SCR). The SCR system is based on the prior injection of ammonia (NH3) as a reducing agent into the gas flow and its subsequent passage through a reactor containing catalyst blocks. Its efficiency is around 95%. The old non-catalytic system equipment (SNCR) is maintained as redundant to support the new equipment in case of maintenance shutdowns.

Emission control system improvements: installation of new FTIR multi-gas analysers at boiler outlet per line, installation of a new mercury (Hg) analyser per line, installation of new integrated FT+FID multi-gas analysers at stack outlet per line.

Analytical results

In accordance with the criterion of transparency that the Consortium has always applied in its management, in this section you can find the updated data on atmospheric emissions from the Centre.