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EMS model

3.1.5 Management tools .1 Overview .1 Overview

3.1.5.2 Inventory management tools .1 Overview .1 Overview

To operate an industrial site in accordance with a good EMS, it is essential to have detailed and transparent information on:

 the site and its environmental circumstances;

 the production processes;

 the characteristics of the pollutants of the individual production processes;

 the characteristics of the emitted streams;

 local factors.

Without this knowledge, it is not possible to develop a coherent, efficient and cost-effective strategy to prevent or reduce emissions. Though it is often virtually impossible to quantify the emissions of each contaminant present in each emitted stream, a way to reduce the necessary parameters (e.g. number of measurements) without relevant loss of information can normally be found.

3.1.5.2.2 Site inventory Description

A site inventory consists of information on:

 geographical location of the installation/site and production units (map and plot plan);

 climate, geography, quality of the soil and groundwater, neighbourhood, and receiving water;

 size of the site (total area, built-up area, drained area, covered area);

 number of employees;

 production units;

 list of production plants including, for each one, data on:

◦ the classification of production plants according to the IED (2010/75/EU), Annex I, 4. Chemical Industry, Sections 4.1–4.6 [ 5, Directive 2010/75/EU 2010 ],

◦ typical production plant data;

 information on the production processes, for each process, including:

◦ a brief description,

◦ simplified process scheme(s) with sources of waste streams,

◦ details of the chemical reactions (main and side reactions) and supporting operations,

◦ information on operating material, intermediate and final products,

◦ operating mode (continuous or batch process or campaign operation),

◦ potential emergency situations (spills, leakages);

 sewer system (sewer, WWTP, rainwater drainage).

Achieved environmental benefits

A site inventory is a tool that is expected to help plant management react more effectively and more quickly to environmental challenges. A site inventory will help in the determination and ranking of the significance of the environmental impacts of the site and in the implementation of an effective EMS to address them (see Section 3.1.2).

Cross-media effects

There are no cross-media effects associated with a site inventory.

Operational data No information provided.

Applicability

The technique is applicable to new and existing installations.

Economics

No information provided.

Driving force for implementation

Improving the environmental management system is the main driving force for the implementation of the technique.

Example plants

No information provided.

Reference literature

[ 5, Directive 2010/75/EU 2010 ]

3.1.5.2.3 Stream inventory/register Description

The compilation of relevant basic data on the composition and quantity of waste water and waste gas streams – each one individually – is done in a stream inventory/register (waste water inventory/register, waste gas inventory/register). The emitted streams are listed respective to their source, i.e. the production process from which they originate. This is a key element in assessing their degree of contamination and the nature of the contaminants, as well as the possibilities of reduction at the source. The sources of waste water are listed in Section 1.4.2;

those for waste gas in Section 1.4.3. Stream inventories/registers form the basis for waste water segregation and pretreatment strategies (see Sections 3.1.5.3.4.2 and 3.1.5.3.5.2).

When waste waters are further treated in a central WWTP, establishing and maintaining a stream inventory/register allows for identifying the pollutants/parameters that can have an influence on the performance of the central WWTP and to take all necessary actions in order to ensure the proper functioning of the WWTP. In this context, a stream inventory/register is a technique used in the framework of conventions (see Section 3.1.3).

A stream inventory/register addresses the following aspects, if relevant to the particular local conditions:

 information about the chemical production process, such as:

◦ chemical reaction equations including starting compounds, products and side products;

◦ simplified process flow sheet of the corresponding production unit, showing reactor, work-up and product isolation, and showing the exact origin of the various emission contributions;

◦ description of process-integrated techniques and waste water/waste gas treatment at source including their performances;

 information, as comprehensive as is reasonably possible, about the characteristics of the streams, such as:

◦ data on concentrations and loads of relevant pollutants/parameters and their variability (including monitoring method and frequency);

◦ stream flow rate and its variability (e.g. pulse dose, continuous flow or batch-wise);

◦ temperature;

◦ pH (for waste water);

◦ conductivity (for waste water);

◦ flammability (for waste gas);

◦ explosive limits (lower explosive limit (LEL) and higher explosive limit (HEL));

◦ reactivity (for waste gas);

◦ relevant contaminants and/or parameters, such as:

▪ COD/TOC, NH4-N, NO3-N and NO2-N, phosphorus, heavy metals, halogenated hydrocarbons, persistent organic pollutants – when expected –

and toxicity in waste water;

▪ chlorine, bromine, fluorine, hydrogen chloride, sulphur oxides (SOX), hydrogen sulphide, mercaptans, carbon monoxide, nitrogen oxides (NOX), particulate matter, heavy metals and their compounds, volatile organic compounds (VOCs) in waste gas;

◦ data on biodegradability (for waste water) such as:

▪ BOD concentrations;

▪ results from modified Zahn-Wellens test;

▪ refractory COD/TOC loads;

▪ denitrification inhibition potential;

◦ presence of other substances (for waste gas), which may have an impact on the treatment system or may be safety issues, such as oxygen, nitrogen, water vapour, and/or dust.

The purpose of a stream inventory/register is to identify the most relevant emission sources (for each medium, waste water and waste gas) and to allow a prioritisation of the emission reduction steps to be taken. Generally speaking, this is a four-step operation including:

 listing of the sources;

 evaluation of the causes of emissions from each source;

 quantification of the amount of emission from each source;

 validation of the results through mass balance(s), the extent of which would depend on several factors (e.g. type of pollutant, frequency of emissions).

An appropriate ranking of the distinctive tributary streams (i.e. individually for waste water and waste gas), corresponding to the characteristics and load of contaminants is a decisive part of the inventory/register and an attractive basis for identification of further release reduction potential, the respective streams at the top of each ranking list being prime candidates for more effective emission reduction.

On chemical sites, measures for the reduction of emissions are best realised for those chemical processes where an optimum ratio of environmental benefit to cost is achievable. For existing installations, non-optimum elimination rates for minor emitted streams not carrying a significant load might be tolerated, when efforts are instead concentrated on streams containing significant loads, thereby reducing overall emissions and environmental impact.

Achieved environmental benefits

Achieved environmental benefits include the reduction of emissions to water and/or air.

Identification of relevant waste water/waste gas streams is a prerequisite for an efficient waste water/waste gas management and for the reduction of emissions by technical and management

Cross-media effects

There are no cross-media effects associated with this technique.

Operational data

At a large chemical site in Germany (about 30 different companies and 100 production plants), the waste water register includes an assessment of all relevant point sources at the different process steps. In this example site, since the organic content at the outlet of the final treatment is relatively low (COD < 75 mg/l) and the waste water effluent does not pose toxicity problems, the waste water register is less detailed and contains 1–15 waste water streams per production unit, depending on the diversity of the waste water arisings. The authorities receive updated data every three years or when major changes are implemented [ 134, LANUV NRW 2008 ].

The waste water register includes an assessment of the waste water volume and pollutant concentrations/loads at the different sources. It includes average data for the respective year on waste water volume and load and concentrations of TOC, AOX, as well as the most common heavy metals (i.e. Hg, Cd, Cu, Ni, Pb, Cr, Sn, Zn) and main compounds known to be present in the waste water (e.g. BTEX, organic products, salts, nitrogen compounds as total nitrogen) coming from the different sources. An additional issue is priority pollutants. Findings of the example plant are discussed in [ 134, LANUV NRW 2008 ].

The register also includes the results of a systematic assessment on the feasibility of potential production-integrated measures to avoid waste water and/or to reduce loads (see Section 3.3).

An example of the basic data on the composition and quantity of waste waters from a multi-purpose plant can be found in the OFC BREF [ 105, COM 2006 ].

Applicability

The technique is generally applicable.

Economics

No information provided.

Driving force for implementation

Inventories/registers may be used to assess the implementation of BAT and may constitute basic information for authorities in order to set emission limit values for the total loads on the basis of balancing models [ 134, LANUV NRW 2008 ].

Example plants

Marl chemical park, North Rhine-Westphalia, Germany [ 134, LANUV NRW 2008 ].

Reference literature

[ 105, COM 2006 ] [ 134, LANUV NRW 2008 ]

3.1.5.2.4 Mass balances Description

Mass balances are one basis for understanding the processes on a site and the development of improvement strategies. For a complete mass balance, the inputs must equal the outputs.

Table 3.2 shows the typical elements of a mass balance. Not every output path is relevant in every case (e.g. heavy metals cannot be destroyed).

Table 3.2:Typical elements of a mass balance

Input Output

- Withdrawal from stock - Purchases

- Production

- Recycling/reuse from other processes

- Deposit in stock - Consumption - Destruction

- Recycling/reuse to other processes - Losses to air

- Losses to water - Disposal

A solvent management plan according to Part 7 of Annex VIII to the IED (2010/75/EU) constitutes an example of a mass balance [ 5, Directive 2010/75/EU 2010 ].

Achieved environmental benefits

Mass balances are essential for understanding on-site processes and the development of improvement strategies.

Cross-media effects

There are no cross-media effects.

Operational data

An example of a water balance for the production of fertilisers is given in the LVIC-AAF BREF [ 102, COM 2007 ].

Mercury balances are a frequently used tool in mercury-cell chlor-alkali plants [ 110, COM 2014 ] [ 124, Euro Chlor 2010 ].

Applicability

This technique can in some cases provide useful insights into a process. Mass balances are very time-consuming and this is a limitation to their use. Mass balances are generally not sufficiently accurate to quantify emissions from a chemical plant.

Economics

Additional measurements are required (hence costs) and, therefore, additional staff are needed.

Driving force for implementation

The driving forces for implementation of the technique are reporting requirements imposed by authorities as well as the development of improvement strategies to reduce pollution.

Example plants

Mercury-cell chlor-alkali plants.

Reference literature

[ 5, Directive 2010/75/EU 2010 ] [ 102, COM 2007 ] [ 110, COM 2014 ] [ 124, Euro Chlor 2010 ]

3.1.5.3 Operational management tools