Kempten HHKW wood and waste incinerator Key figures & facts - March 2020

  • 60 000 tons of wood and waste / year treated since 1998
  • Using SOLVAir® solution since August 2018
  • Sorbent Stoichiometric ratio at or below 1,1 
  • Stack monthly emission averages (mg/Nm3 dry, O2<11%) : HCl 3, SO2 7, NOX < 80, Hg 0,0045
  • Around 25000 tons / year of avoided CO2 
  • 85 Millions kWh / year of district heat
  • Plant availability factor: 95 to 96%
  • Maximum load reached: 49.000t waste / year
  • Total electrical energy production: 20,8 GWh
October 1, 2020

Webinar - Flue gas cleaning in Waste to Energy plants

Discover

Kempten’s wood and waste incinerator’s needs

The primary task of ZAK Energie GmbH is the thermal disposal and energy recovery of residual waste. For this purpose ZAK operates among others 2 incineration lines in Kempten that treat around 80 000 tons of waste per year since 1996 and additional 60 000 tons of wood and waste per year since 1997. The last built incinerator is using SOLVAir® technology since the recent revamping of the flue gas treatment. 

Meeting stringent new NOX Emission Limits

Formerly, the gases were treated with a conditioned hydrated lime based flue gas treatment in combination with a Selective Non Catalytic Reduction (SNCR). This technology wasn’t enough to meet new stringent emission limits (especially for NOX  with low ammonia slip). 

 

What does SOLVAir® provide to ZAK Energie GmbH for Kempten wood and waste incinerator?

Synergies with tail-end Selective Catalytic Reduction (SCR)

To comply with NOX regulations, a tail-end Selective Catalytic Reduction (SCR) was installed. Since this technology requires high flue gas temperature and because sodium bicarbonate overtakes lime performance at this temperature,  ZAK Energie GmbH was also recommended to set up a bicarbonate based dry sorbent injection.

A 100% safe, ready-to-use sorbent to avoid extra maintenance costs

After establishing a technical diagnosis of the plant, SOLVAir® team has proposed a configuration with SOLVAir® SB 0/3 ready-to-use sodium bicarbonate based sorbent.

“We chose the innovative SOLVAir® SB 0/3 ready-to-use sorbent because we wanted to avoid any extra investments and maintenance of the grinders. This flue gas cleaning system meets all our expectations in terms of efficiency, reliability and energy efficiency.”

Christoph Lindermayr
Responsible for energy management.

Benefits for ZAK Energie GmbH

High energy recovery

The SCR’s catalyst can operate without gas reheating, allowing the incinerator to consume less energy and to provide more, which results in great energy recovery rates: 

  • 85 Millions kWh of district heat produced per year
  • 48% contribution of the wood and waste line

A long term operation reliability and constant compliance with stringent legislations

With SOLVAir®, the plant is more flexible for meeting future lower Emission Limit Values and using different types of fuels (waste, all wood classes) since only the sorbent quantity needs to be adapted. Finally, the plant achieved very low emission rates, 3 to 10 times below the regulation values (mg/Nm3 dry, O2<11%):

  • HCl
  • SO2
  • NOX < 80 
  • Hg 0,0045

Reduced Maintenance and operation costs

The use of SOLVAir® SB 0/3 ready-to-use sorbent enabled our customer to significantly reduce its operation costs since no extra investments and grinders maintenance are required.

 

Requirements of BREF WI legislation for Waste to Energy facilities

ZAK Energie GmbH is already ready for the new BREF air emission limits.

 

Current Emission limits

(mg/Nm3 dry, O2<11%)

New BREF WI

(mg/Nm3 dry, O2<11%) for existing permits

November 2019 average emissions

(mg/Nm3 dry, O2<11%)

HF (Hydrofluoric acid)

1

1

0.28

HCl (Hydrochloric acid)

10

8

3

SO2 (Sulfur dioxide)

50

40

7

NOX (nitrogen oxides)

150

150

<80

NH3 (Ammoniac)

10

10

5

Dust

5

5

0.1

CO (carbon monoxide)

50

50

9

Sb-Sn (antimony / tin)

0.5

0.3

0.0104

TOC (Total organic carbon)

10

10

0

PCDD/F (Dioxins/Furans) (in ng/Nm³ TEQ)

0.1

0.08

0.000020

Hg (Mercury)

0.05

0.02

0.0045

During implementation the team in Kempten showed a very pragmatic, professional and open approach in order to successfully realize this project. After references in Benelux and Switzerland, an increasing number of customers also in Germany are choosing this most innovative SOLVAir®Solution.

Michael Steiner
Sales Development Manager