Technical informationTECHNOLOGY

VOL.24 NO.1 (published in Jun-2016)

Photo in Cover :Woody Biomass-fired Circulating Fluidized Bed Boiler
VOL.24 NO.1 (published in Jun-2016)
Joint Study Report with Tokyo Metropolitan Government on Sewage Sludge Incinerator
Yukiya ATSUMI*,Toru SASAKI*,Hiroki WADA*,Naoki KABUTAN*
(*Sewerage Engineering Dept.)


Establishing the standards for the sewage sludge incinerators for the purpose of reducing greenhouse gases and utilizing renewable energy, Tokyo Metropolitan Government Bureau of Sewerage has set "high-temperature energy-saving sludge incinerator" and "energy selfreliant sludge incinerator," expanding their introduction, respectively. We conducted two joint studies together with Tokyo Metropolitan Government Bureau of Sewerage in 2014 and their compliance with the above-mentioned incinerators was approved by meeting their respective standards.

The Demonstration Study of Power Generation System with Sewage Sludge Incineration ; Part 3 -Report on Demonstrative Operation toward Expanded Scope of Innovative Step Grate Stoker Furnace-
(*Sewerage Engineering Dept.)


In 2013 and 2014, this demonstration study was entrusted by National Institute for Land and Infrastructure Management as B-DASH project. In 2015, a mixed incineration test with dry sludge and screen residue was conducted for the purpose of expanding the scope of an innovative step grate stoker furnace used in this study. As a result, it was confirmed that stable incineration was allowed in mixed incineration with dry sludge, and that auxiliary fuel consumption was reduced by mixed incineration with dry sludge even in case an auxiliary fuel is required such as when a water content increases. In mixed incineration with screen residue, an N2O emission factor was much the same as a fluidized bed incinerator (high-temperature incineration at 850℃) because an incinerator outlet gas temperature was low, but incineration was allowed without problem from an aspect of environmental load. Even if dewatered sludge is accepted, it was confirmed that operating cost was greatly reduced by drying and burning it in mixed incineration, compared with conventional technology.

Evaluation of Sewage Sludge Incinerating Power Generation System by Step Grate Stoker Furnace
Satoshi HAGITA*1,Takaaki MIZUNO*1,Naoki KABUTAN*1,Kenichi SHISHIDA*1
Kazuyuki OSHITA*2,Masaki TAKAOKA*2
(*1Sewerage Engineering Dept.,*2Department of Global Ecology, Graduate School of
Global Environmental Studies, Kyoto University


Concerning a waste heat power generation system of sewage sludge incineration by step grate stoker furnace, we compared an energy available amount, greenhouse gas emissions and running cost with other technology as evaluation items in a joint study with Kyoto University. Comparison systems were a bubbling fluidized bed furnace as a conventional incineration system and a fuelization system as other technology for energy recovery, and the respective systems were combined with the conditions such as whether a digestion system is provided or not, and the type of dewatering devices. As a result, it was found that the sewage sludge incinerating power generation system by step grate stoker furnace was most superior in terms of running cost and exhibited high performance in terms of the energy available amount and greenhouse gas emissions as well. It was also confirmed that the step grate stoker furnace required less energy amount for running the facility and had excellent energy self-reliance.

Selective Non-catalytic Reduction (SNCR) Test with Urea Decomposing Device (Part 2)
Masaaki KURATA*,Hiroki FUJIHIRA*,Norio MAEDA*
(*Energy & Environmental Development Dept.)


We developed a system designed for spraying ammonia obtained by resolving urea with a catalyst into an incinerator as a reducing agent for denitration. Last year, after manufacturing a pilot test apparatus at an actual machine scale and collecting basic data to establish a condition which allows a urea-to-ammonia conversion rate to be 100%, we conducted a denitration performance test by spraying an ammonia gas generated from the test apparatus into the stoker type incinerator of the actual facility (200 tons/day incinerator). As a result, urea water consumption was reduced by approx. 50% compared with a method for spraying urea water into the incinerator, as previously reported. This time, as a result of additionally confirming long-term control stability and continuous operability of a urea decomposing device in another large-scale facility (270 tons/day incinerator), it was confirmed that NOx concentration of chimney was able to be stably controlled for a long period. When compared at the required NOx removal rate of 30% and the same combustion chamber gas temperature (850 to 900℃), it was reconfirmed that urea water consumption was reduced by 50% or more, compared with a conventional urea water spraying method.

Electric Double Layer Waste Water Treatment System
Muneharu FUJIKAWA*
(*Energy & Environmental Development Dept.)


In order to strike a balance between higher power output and a waste water closed system at a waste incineration facility, we developed an electric double layer waste water treatment system. We conducted a basic performance test on the electric double layer waste water treatment system and another performance test on the system with its treatment capacity scaled up to 2.4 m3/day, and obtained favorable results. We automated the scaled-up system to conduct a plant waste water treatment test at a waste incineration facility. As a result we succeeded in treating the waste water up to a water quality capable of continuously meeting the standard of device cooling water make-up feed.

Report on Operation of Woody Biomass-fired Power Generation Boiler
Kosaku OMORI*,Koji IKEDA*
(*Energy Engineering Dept.2)


Introduction of renewable energy has been actively promoted by a feed-in tariff system for renewable energy, introduced in Jul. 2012. Making use of this system, MANIWA BIOMASS POWER Co., Ltd. established centering on MEIKEN LAMWOOD Corp., a laminated wood maker in Maniwa, Okayama, decided to start a woody biomass power generation business, and we delivered a power generation boiler plant for that purpose. This report outlines the woody biomass-fired power generation boiler facilities delivered in Apr. 2015 and provides the information on its operation results. In a performance test on this power generation boiler plant, it was confirmed that the plant realized favorable combustion of woody biomass and achieved design performance.

Report on Operation of Woody Biomass-fired Circulating Fluidized Bed Boiler
Yuki SAKATA*,Akihiro SAIGA*,Teruyuki KITA*
(*Energy Engineering Dept.I)


Delivering more than 580 boilers responding to different fuels such as woody chips and bagasse (strained lees of sugarcane) since the 1950s both domestically and overseas, we have proposed the most suitable combustion systems, taking account of the conditions such as calorific values, component compositions and shapes of various fuels. With highly evaluated technology and know-how endorsed by our abundant track record, we have received 25 or more orders for biomass power generation plants since a "feed-in tariff system for renewable energy" was initiated in Jul. 2012. As a process steam (for drying wood product) feed boiler at Chugoku Mokuzai Co., Ltd., we installed a circulating fluidized bed boiler in Jul. 2015, which uses woody biomass as a fuel. The report outlines these boiler plant facilities and provides the information on operation results when using woody biomass and other fuels.

Operation & Maintenance Administration Support System (POCSYSR)
Takashi HASHIMOTO*1,Junichi TANAKA*2
(*1Operation & Maintenance Administration Dept., *2Electrical & Instrumentation Dept.)


Along with an increasing number of management businesses of municipal waste disposal plants by DBO and O&M projects these days, long-term stable management of these facilities has been demanded. In light of such a background, we newly built an "operation and maintenance administration support system (POCSYSR)" designed for higher-efficiency operation and maintenance administration, and creation of new value added. This system accumulates and manages various data including operation data in a unique integrated server in a unified manner, and have different operation support functions used for operation and maintenance administration, and a function to analyze the accumulated data. This report outlines the configuration and each function of this system.