No. 8E - August 1995

Waste incineration

- Environmental requirements for municipal plants and hospital plants

Limit values on emissions from waste incinerators are strict in order to reduce the negative effects of emissions of acidic components and micropollutants. Only residual waste is allowed to be inicinerated. 20 percent of the municipal waste in Norway in 1994 was incinerated. There are presently 8 municipal plants, 3 plants for hospital waste, and 6 that only incinerate biological/pathological waste.

The most serious negative effects of waste incineration are the emissions to the air. These emissions contribute to the formation of acidic components and spread heavy metals like cadmium, mercury and lead, as well as microorganic pollutants like PAH and dioxins into the environment. The level of emissions are to a great extent dependent on how well the cleansing systems for the emissions work. The main goal is to reduce the level of micropollutants to as low level as possible because these pollutants never or very slowly break down and therefore accumulate in the food chain.

The micropollutants dioxins, mercury, cadmium are considered the most serious problems in relation to waste incineration. Dioxins are considered to be the most poisenous material in existance. It breaks down very slowly and accumulates in the food chain. Mercury is very poisenous and bioaccumulates. Cadmium is poisenous for organisms living in water and accumulates in these organisms. Furthermore can kidney damage occur as well as mutagenic effcts, and reduced ability for reproduction in humans and animals.

Waste incineration also leads to emissions to water from wet scrubbers and from the landfill site where slags and ashes are landfilled. Noise and odour may be a problem related to waste incineration, but it is considered a small problem. Increased traffic may have an impact locally.

Status

71 percent of the total amount of municipal waste is landfilled, 20 percent is incinerated, 1 percent composted, 4 percent is sorted for recycling at the waste treatment facility, and 4 percent goes directly to a material recycling facility.

Presently there are 5 large waste incineration plants for municipal waste with a capacity of more than 5 tons per hour. The level of energy recovery in these plants is between 20 percent and 80 percent, with a total level of energy recovery at aproximately 60 percent. There are 3 small and medium sized plants for municipal waste and 3 for hospital waste. In addition permits have been issued to 6 hospitals for incinerating biological/pathological waste only. The incinerators are equipped with advanced gas cleansing systems. The incinerators that only incinerate biological/pathological waste are only equipped with a simple separator for particulates. The residues from the cleansing processes are landfilled at a landfill site for hazardous waste. The bottom slag is landfilled at regular sanitary landfills, and may be used as filling material in roads etc.

The EEA agreement

Several directives and regulations must according to the EEA agreement be implemented in Norwegian laws. This includes the following council directives:

Council Directive on the reduction of air pollution from new municipal waste-incineration plants (89/369/EEC)
Council Directive on the reduction of air pollution from existing municipal waste-incineration plants (89/429/EEC)

In Norway waste incineration have so far been regulated in individual permits issued to the plant owner. A separate regulation on incineration of municipal waste referring to the two council directives have been adapted, since the permit system has not been considered as sufficient implementation of the council directives on incineration of municipal waste. Norway therefore implemented the above mentioned council directives in Norwgian law in Regulation of May 24. on incineration of municipal waste. The requirements put forward in the indvidual permits are stricter than the council directives so the regulation have in fact no practical consequences for the Norwegian plants.

Limit values and other requirements in the permits

Municipal waste incineration plants are only allowed to incinerate residual waste. This means waste that for technical or socioeconomic reasons can not or should not be reused or material recycled.

A separate evaluation of necessary limit values and other requirements are made in each case based on local conditions such as topographic conditions, air quality and the location of waste recycling facilities. In the tables below an overview of the requirements in the current permits are given. New waste incineration plants may receive stricter limit values.

Emission limit values to the air for plants with the capacity greater than 3 tons/hour (existing plants, municipal and/or hospital waste). Table 1:

Pollutant	Limit values ¹⁾		Measurements			Instruments for continous surveillance
	12 hour average mg/Nm³	1 hour average mg/Nm³	Measure- ment frequency	Sampling number pr measure- ment	Minimum sampling time	Logging frequency	Minimum time pr registr
Particulates	30		yearly	4	1 hour	1 hour	1 hour
Hg	0,05		yearly	4	1 hour	-	-
Cd	0,05		yearly	4	1 hour	-	-
Pb+Cr+ Cu+Mn	5		yearly	4	1 hour	-	-
Ni+As	1		yearly	4	1 hour	-	-
CO	-	100²⁾	yearly	cont	cont	5 min	1 hour
HF(uorg. fluorid )	2		yearly	4
HCl (uorg klorid(g))	50		yearly	4	1 hour	1 hour	1 hour
TOC	20		yearly
SOx (SO2)	300		yearly	4/cont	1hour	1 hour
Dioxins	2 ³⁾	-	yearly	3	3 hours	-	-

Emission limit values to the air for plants with the capacity less than 3 tons/hour (municipal and/or hospital waste). Table 2:

Pollutant	Limit values ¹⁾		Measurements			Instruments for continous surveillance
	12 hour average mg/Nm³	1 hour average mg/Nm³	Measure- ment frequency	Sampling number pr. measure- ment	Minimum sampling time	Logging frequency	Minimum time pr. registr.
Particulates	100		yearly	4	1 hour	1 hour	1 hour
Hg	0.1		yearly	4	1 hour	-	-
Cd	0.05		yearly	4	1 hour	-	-
Pb+Cr+ Cu+Mn	5		yearly	4	1 hour	-	-
Ni+As	1	yearly	4	1 hour	-	-
CO	-	100 ²⁾	yearly	cont	cont	5 min	1 hour
HF(uorg. fluoride )	4		yearly	4
HCl (uorg. chloride(g))	100		yearly	4	1 hour	1 hour	1 hour
TOC	20		yearly
SO_x (SO₂)	300		yearly	4/cont	1 hour	1 hour
Dioxins	2 ³⁾	-	yearly	3	3 hours	-	-

¹⁾Referred to 11 vol% O2, Temp. 273K, Pressure 101,3 Pa
²⁾1/2 hour average up to 150 mg/Nm3 a is accepted
³⁾ng/Nm3 2378 TCDD-equivalents (Nordic standard)

Emission limit values to the air for plants that incinerate biological/pathological waste. Table 3:

Pollutant	Limit value	Surveillance measurement			Instruments for continous surveillance
	12 hour average mg/Nm³	Measure- ment frequency	Sampling numbers pr. measure- ment	Minimum sampling time pr. sample	Logging frequency	Minimum sampling time pr. reg.
Particulates	100	every 2 year	4	1hour	1 min	1 hour
Hg	0,1	every 2 year	4	1hour	-	-
HCl (uorg. chloride(g))	150	every 2 year	4	1hour	-	-
CO	100 ¹⁾	every 2 year	cont.	cont.	1 min	1 hour

¹⁾The requirement for CO is hourly average

Emission limit values to water from plants with wet scrubber (independent of size). Table 4:

Pollutant	Limit value	Measurements	Minimum sampling time pr. sample	Measurement instruments
pH Hg	6-10 0,002 mg/l	continously weekly/logged *	logging over 12 hour weekly mixed sample **	continously water sampler proportional to the water flow
Cd	0,005 mg/l	monthly	weekly mixed sample**	«
Pb	0,05 mg/l	monthly	weekly mixed sample**	«
suspend material	10 mg/l	monthly	weekly mixed sample**	«
temp	50°C	monthly	logged over one week	continuosly
SO₄2-	municipal limit values	monthly	weekly mixed sample **	«
Cl-	municipal limit values	monthly	weekly mixed sample **	«

The limit values are related 250 l vann per tonn waste. Norwegian Standard for sampling shall be used when this exist.
* The use of continous sampling instruments may reduce the number of mesurements
** Each sample is related to the waterflow in the plant.

Technical requirements. Table 5:

Parameter	Requirement	Logging frequence
Temperature i the secondary zone	> 850 °C	1 min
Time in the secondary zone after last injection of combustion air	> 2 seconds
Ignition loss in bottom slag	< 5 % C by weight	4 times/year