Technical InformationTECHNOLOGY

VOL.30 NO.1 (published in Jun-2022)

Photo in Cover :Seibu Sludge Center in Sapporo City
VOL.30 NO.1(published in Jun-2022)
Current Status of Carbon Pricing
Momoko TAKEDA*
(*Technology Planning & Administration Dept. (Tokyo))


Carbon pricing is a policy approach that leads to climate change mitigation by attaching monetary value to greenhouse gas. The introduction and consideration of this technique has been continuing for some time and more than 30 years have now passed since the worldʼs first carbon tax was introduced by Finland. However, it has been attracting even more attention recently with the increase of carbon neutrality worldwide. In addition, the Glasgow Climate Pact at the COP26 held in November last year further reinforced the importance of tackling CP. In Japan, consideration began in earnest after the CN declaration in 2020 and there are currently proposals for a review of the global warming tax by the Ministry of the Environment, and for the establishment by the Ministry of Economy, Trade and Industry of a carbon credit market and a green transformation league concept assuming an independent emission trading system. If CP is fully introduced, it is thought that it will have a major impact in the refuse sector and on biomass power generation. This paper explains the trends in CP and also tries to examine the impacts in the refuse sector. Note that this report was compiled based on information up to early February 2022, and that there is a possibility of rapid change in the future.

Report on Demonstration Testing for the Application of a Pressure Wave Boiler Dust Removal System (VSPS) to a Boiler Economizer
Kyohei HAYASHI*, Kotaro KATOH*, Yasuyuki FUJITA*
(*Energy & Environmental Development Dept.)


For boiler dust removal equipment, our company has developed an original pressure wave boiler dust removal system as a substitute for the conventional steam type soot blower. A previous paper reported the results of demonstration testing for the application of this equipment to the superheat tubes of municipal waste incinerators where the quantity of refuse is 110 tons per day per furnace and 250 tons per day per furnace. For the purpose of application to economizers, this paper reports the results of demonstration testing of application to an economizer of a municipal waste incinerator where the quantity of refuse is 240 tons per day per furnace

Development of Compact High- Speed Uniflow Machine
Atsushi SAKIYAMA*, Seiichiro YAMAMOTO*, Kengo KISHI*, Akihiro NISHIDA*
(*Sewerage Engineering Dept.)


For renewal work for existing sewage treatment plants, which has been increasing in recent years, our company proposes a change of method from the existing fixed bed sand filtration equipment to the upflow moving-bed sand filtration system (Uniflow Sand Filter). In order to expand the opportunities for Uniflow application in the renewal work, we have developed the development of a compact machine with reduced its height. By conducting the demonstration experiments, we confirmed the normal operation and prescribed performance of the compact machine.

Approaches to Achieve Automated Operation in Waste Treatment Plants
Takayuki KUDO*, Munechika ITOH*
(*Environmental Engineering Dept. 1)


Future refuse treatment facilities will be required to continue the waste treatment which matches the needs of the age, while also coping with the labor shortages arising due to the decreasing birth rate and aging population, and the decrease in the working population. Our company is aiming to solve this problem by working on the further automation of facility operations. One of those initiatives is the development of the Intelligent Control System (ICS) using AI technology, and this has realized the high-level automated operation of incineration equipment. However, there were cases in which manual intervening operation became necessary on the equipment other than the incineration equipment. In this new development, in addition to the automated operation using ICS, we also introduced manual intervention suppression control on equipment other than the incineration equipment, so that manual intervening operation for the refuse treatment plant could be almost eliminated. This has therefore brought the realization of the automated operation of refuse treatment plants even closer.

Smartification of Waste Receiving Systems
(*Environmental Engineering Dept. 1)


Conventionally, the “waste receiving systems” performing the receiving/storage/mixing operations have relied on manual operations by the facility workers, including for the waste crane operation and settlement of fees. However, the decrease in the working population in recent years has led to demands for labor saving. Furthermore, there has also been the new issue of reducing face-to-face work from the viewpoints of improving convenience and preventing the spread of COVID-19. Our company is working to solve these issues through ICT for the smartification of waste receiving systems, including by actively introducing vehicle number readers, waste level sensors and others

Application of Powder Simulation for Analysis of Lower Hopper of Bubbling Fluidized Bed
Shota WADA*
(*Energy Engineering Dept. 1)


In recent years, the versatility of numerical simulation technology has been recognized and it has been actively utilized for research and equipment development. Advances in numerical simulation technology have made it possible to visualize the behavior of engineering processes and to quantify various elements related to that behavior. In the designing of equipment in particular, the technology has been a great help in the aspects of development time reduction and performance improvement. In this paper, the powder analysis software iGRAF® was used to simulate the process in which the powder filled in a quadrangular pyramidal hopper is discharged from the bottom. This is a report of the results of a comparison of the simulation and the behavior on an experimental machine

Report of Trial Operation of a Sewage Sludge Incinerating Power Generation System at the Seibu Sludge Center in Sapporo City
(*Sewerage Engineering Dept.)


Our company delivered an energy saving・energy creation type sewage sludge incinerating power generation system that combines sewage sludge incineration and steam power generation equipment using the incineration waste heat to the Seibu Sludge Center in Sapporo City. This system combines elements such as a dryer, a step grate stoker furnace, a waste heat boiler, and a steam generator. It does not require the use of auxiliary fuel in the sludge incineration and can realize a drastic reduction of the power consumption in a plant through low power consumption and steam power generation. In addition, it is possible to perform high-temperature incineration at over 900℃, so it is possible to drastically reduce the discharge of dinitrogen oxide, which is a greenhouse gas. It is therefore a sewage sludge incinerating power generation system which simultaneously realizes energy saving・energy creation, running cost reduction, and greenhouse gas reduction. This equipment has been in stable operation with the required performance satisfied from its completion in August, 2021 to the present day.

Operation Report for Clean Plaza of the Regional Cleaning Union of Ota City and Three Towns
(*Environmental Design Dept. 3)


In March 2021, “The Clean Plaza” of the Regional Cleaning Union of Ota City and Three Towns was completed. This facility was constructed for the wide-area treatment of combustible waste from Ota City, Chiyoda Town, Oizumi Town and Ora Town in the eastern part of Gunma Prefecture.
 This facility was constructed and is operated based on our business proposal of the “Realization of high-efficiency waste power generation (power generation efficiency 26.2%)” and “Stable operation combining our companyʼs extensive past results and the latest technologies”. This paper mainly reports the results of delivery performance tests regarding the high-efficiency waste power generation, and the introduction of the latest technologies.

Takuma Technical Review