Sludge Watch ==> Akron Ohio - end of sludge compost - starting power from sludge

[Maureen Reilly]

Power station generates excitement in Akron
Sludge plant is real gas
$7 million facility turns sewage waste into clean electricity

By Bob Downing
Beacon Journal staff writer


Published on Thursday, Dec 13, 2007

''Taking our brown and turning it into green'' was the way Akron Water 
Pollution Control Administrator Brian Gresser described a new facility that 
turns the city's sewage sludge into electricity.

The green-energy project ''makes a positive out of a negative,'' Akron Mayor 
Don Plusquellic said of the electricity derived from sludge.

The process will '''save taxpayers a good deal of money . . . and it will be 
good for the environment,'' he said.

The city and its partner, KB Compost Services Inc. of Independence, held a 
press conference Wednesday to show off the new $7 million facility at the 
city's composting plant off Riverview Road.

Since mid-October, Akron and KB Compost have been fine-tuning the plant that 
turns sludge from the city's sewage treatment plant into a methane-rich 
biogas that powers an electric generator.

The new facility is owned by the city and operated by KB Compost, the 
company that also manages the city's composting plant.

If the new facility works as well as expected, Akron will look into 
expanding the operation and shutting down the composting plant, which 
triggers odor complaints from people living in and at the edge of the 
Cuyahoga Valley, Plusquellic said.

He said he is unable to say when that might occur.

Akron's system — the first of its design in the United States — was 
developed by Schmack Biogas AG in Germany. That company has 200 operations 
in Asia and Europe.




KB Compost Services has partnered with Schmack Biogas AG to form a new 
company, Schmack BioEnergy LLC in Independence, to promote the German 
technology in the United States.

It was outside Zurich, Switzerland, where Plusquellic first inspected a 
biogas operation four years ago.

''I knew we had the infrastructure largely in place to do this in Akron and 
it makes sense for us to get the most out of materials we'd otherwise 
discard,'' Plusquellic said. ''This has wide-ranging benefits for us.''

Akron's initial biogas project is designed to handle 5,000 tons of sludge 
per year, or about one third of the 15,000 tons produced annually at the 
city's sewage treatment plant off Akron-Peninsula Road.

Power station


The new system relies on an engine-driven generator. It is producing 335 
kilowatts, or enough electricity to power 325 homes. About 30 percent of the 
power will be used at the sewage plant and the rest will be used by the 
composting operation.

The city currently spends nearly $1.4 million on electricity for its sewage 
treatment, and that will be money saved, Gresser said.

The new operation makes Akron's facility the first sludge plant in the 
country to produce electricity with the help of bacteria, the city said.

The system relies on bacteria that do not need oxygen, a process known as 
anaerobic digestion. The bacteria cause the high-solids sludge to ferment.

The bacteria multiply, consume part of the sludge and produce a methane-rich 
burnable gas called biogas, said Annette Berger, vice president of 
operations at KB Compost Services.

Key to the system are two tanks: one capable of processing 160,000 gallons 
of sludge and a second that can hold 450,000 gallons. The sludge will be 
processed for 25 to 30 days at temperatures of 90 to 100 degrees.

Akron got its start-up bacteria in sludge from the city of Kent, Gresser 
said.

The biogas will be 60 percent methane, 35 percent carbon dioxide and 5 
percent other gases. In comparison, natural gas is 99 percent methane.

Akron paid for 10 percent of the $7 million project, which was funded in 
part by the Summit County Port Authority.

Evaluation planned


After an 18-month performance evaluation, the city and KB Compost will 
negotiate a new contract and potential expansion of the system to process 
all of the city's sludge.

If the system does not meet agreed-upon performance criteria, then the 
city's financial obligation ends.


Gresser said the process will help reduce the city's escalating costs in 
handling sewage waste from Akron and its suburbs.

Akron and KB Compost realized that a technology other than composting was 
needed to stabilize the ever-increasing cost of sludge treatment and 
disposal.

The composting plant handles 1.2 million gallons of sludge every week, and 
the city spends $6.2 million annually to handle its sewage sludge.

''We'd like to eventually replace the composting plant,'' Plusquellic said. 
''It has served Akron well for more than 20 years, but it's getting old and 
the odors are still an occasional problem for us.''

Before the composting plant opened in 1986, Akron incinerated its sewage 
sludge. That ended in 1993.

Gresser said the city might be able to shut down the composting operations 
if the biogas facility is expanded, but the sludge dewatering part of that 
plant will likely remain open.

Most people give little thought to what happens to their trash or sewage 
sludge, but those are big and costly issues that cities like Akron must deal 
with, Plusquellic said.



--------------------------------------------------------------------------------
Bob Downing can be reached at 330-996-3745 or bdowning at thebeaconjournal.com.

''Taking our brown and turning it into green'' was the way Akron Water 
Pollution Control Administrator Brian Gresser described a new facility that 
turns the city's sewage sludge into electricity.

The green-energy project ''makes a positive out of a negative,'' Akron Mayor 
Don Plusquellic said of the electricity derived from sludge.

The process will '''save taxpayers a good deal of money . . . and it will be 
good for the environment,'' he said.

The city and its partner, KB Compost Services Inc. of Independence, held a 
press conference Wednesday to show off the new $7 million facility at the 
city's composting plant off Riverview Road.

Since mid-October, Akron and KB Compost have been fine-tuning the plant that 
turns sludge from the city's sewage treatment plant into a methane-rich 
biogas that powers an electric generator.

The new facility is owned by the city and operated by KB Compost, the 
company that also manages the city's composting plant.

If the new facility works as well as expected, Akron will look into 
expanding the operation and shutting down the composting plant, which 
triggers odor complaints from people living in and at the edge of the 
Cuyahoga Valley, Plusquellic said.

He said he is unable to say when that might occur.

Akron's system — the first of its design in the United States — was 
developed by Schmack Biogas AG in Germany. That company has 200 operations 
in Asia and Europe.




KB Compost Services has partnered with Schmack Biogas AG to form a new 
company, Schmack BioEnergy LLC in Independence, to promote the German 
technology in the United States.

It was outside Zurich, Switzerland, where Plusquellic first inspected a 
biogas operation four years ago.

''I knew we had the infrastructure largely in place to do this in Akron and 
it makes sense for us to get the most out of materials we'd otherwise 
discard,'' Plusquellic said. ''This has wide-ranging benefits for us.''

Akron's initial biogas project is designed to handle 5,000 tons of sludge 
per year, or about one third of the 15,000 tons produced annually at the 
city's sewage treatment plant off Akron-Peninsula Road.

Power station


The new system relies on an engine-driven generator. It is producing 335 
kilowatts, or enough electricity to power 325 homes. About 30 percent of the 
power will be used at the sewage plant and the rest will be used by the 
composting operation.

The city currently spends nearly $1.4 million on electricity for its sewage 
treatment, and that will be money saved, Gresser said.

The new operation makes Akron's facility the first sludge plant in the 
country to produce electricity with the help of bacteria, the city said.

The system relies on bacteria that do not need oxygen, a process known as 
anaerobic digestion. The bacteria cause the high-solids sludge to ferment.

The bacteria multiply, consume part of the sludge and produce a methane-rich 
burnable gas called biogas, said Annette Berger, vice president of 
operations at KB Compost Services.

Key to the system are two tanks: one capable of processing 160,000 gallons 
of sludge and a second that can hold 450,000 gallons. The sludge will be 
processed for 25 to 30 days at temperatures of 90 to 100 degrees.

Akron got its start-up bacteria in sludge from the city of Kent, Gresser 
said.

The biogas will be 60 percent methane, 35 percent carbon dioxide and 5 
percent other gases. In comparison, natural gas is 99 percent methane.

Akron paid for 10 percent of the $7 million project, which was funded in 
part by the Summit County Port Authority.

Evaluation planned


After an 18-month performance evaluation, the city and KB Compost will 
negotiate a new contract and potential expansion of the system to process 
all of the city's sludge.

If the system does not meet agreed-upon performance criteria, then the 
city's financial obligation ends.

Gresser said the process will help reduce the city's escalating costs in 
handling sewage waste from Akron and its suburbs.

Akron and KB Compost realized that a technology other than composting was 
needed to stabilize the ever-increasing cost of sludge treatment and 
disposal.

The composting plant handles 1.2 million gallons of sludge every week, and 
the city spends $6.2 million annually to handle its sewage sludge.

''We'd like to eventually replace the composting plant,'' Plusquellic said. 
''It has served Akron well for more than 20 years, but it's getting old and 
the odors are still an occasional problem for us.''

Before the composting plant opened in 1986, Akron incinerated its sewage 
sludge. That ended in 1993.

Gresser said the city might be able to shut down the composting operations 
if the biogas facility is expanded, but the sludge dewatering part of that 
plant will likely remain open.

Most people give little thought to what happens to their trash or sewage 
sludge, but those are big and costly issues that cities like Akron must deal 
with, Plusquellic said.



--------------------------------------------------------------------------------
Bob Downing can be reached at 330-996-3745 or bdowning at thebeaconjournal.com.