Technical informationTECHNOLOGY

VOL.28 NO.1 (published in Jun-2020)

Photo in Cover :Oshu Kanegasaki Administrative Association Improvement Work
VOL.28 NO.1 (published in Jun-2020)
Refractories Used in MSW Incinerators and Their Characteristics
Kiyoshi SHIBATA*
(*Mechanical Design & Engineering Dept.)


Refractories are used in the steel industry, in high temperature chemical industries, such as in rotary kilns for sintering cement clinker and glass melting furnaces, in various incinerators and combustion furnaces and elsewhere. The qualities and compositions of refractories used varies depending on the conditions of use in each furnace. The refractories used in MSW incinerators are mainly used in their combustion chambers. Refractories from the MSW incinerator used in the combustion chamber are essential for stable continuous operation and boiler protection. Therefore, long life and maintainability of refractory are important. In this paper, the refractories classification and characteristics are introduced, the refractory composition used in the MSW incinerator is introduced as an example, and the contents of past trouble cases and improvement methods are explained.

Development of Automatic Combustion Technology using Artificial Intelligence in Waste Treatment Plants ( First report)
Yuki FUJIMOTO*,Munechika ITO*
(*Environmental Design Dept. 1)


In waste treatment plants from now on, stable waste treatment must be continued as previously whilst also dealing with a labor shortage due to the aging population, decreasing birth rate and the fall in the working population. To solve this problem, our company is working on the further automation of plant operation. As an example of this, this paper is a report on technology for the automatic stabilization of the combustion condition in the incinerator, which is the most important equipment in waste treatment plants. Artificial intelligence (AI) was developed to predict combustion fluctuations based on operation data and images of the combustion in an incinerator, in the same way as is performed by experienced operators. Real-time prediction was then carried out in an actual plant. The predictions by the AI were compared with the predictions of the actual operator to confirm the prediction performance of the AI. It was also confirmed that learning by the AI based on the data accumulated in the system made it possible to keep prediction performance in accordance with the changes in the operating situation.

Development of a System for the Quantification of the Degree of Waste Mixing Using Image Processing
Ryoichi SEKINE*,Hiroyuki FUJIKAWA*
(*Electrical & Instrumentation Dept.)


A system was developed to quantify the visual sense of the operator (regarding variations in the color tone), for the purpose of upgrading the waste crane automation function and achieving greater homogeneity in the waste in a waste pit than when using the conventional automatic stirring control. This system uses a laser scanner installed on a waste crane girder to perform the three-dimensional measurement of the height of the waste in a waste pit. Those measured values are then used to convert an ITV image of the waste pit into an image viewed from directly above the pit. Furthermore, pixels of a specific color tone are extracted from the color components of the converted image and the area ratio and dispersion of the extracted pixels in each waste pit address are calculated to make it possible to quantify the degree of mixing of the waste. This system was used to quantify the degree of mixing of the waste in green waste bags in an actual plant.

Oshu Kanegasaki Administrative Association Improvement Work
(*Environmental Design Dept. 3)


Our company received an order from the Oshu Kanegasaki Administrative Association, for improvement work on the waste incineration facilities at the Tanko Regional Sanitation Center. The handing over of the 1st stage construction work section (the No. 2 incinerator and part of the common facilities) was completed on September 1, 2019. This construction work was unprecedented for our company. Gas cooling system of the incinerator was improved from a water injection system to a waste heat boiler system and also a steam turbine generator was added to perform electric power generation. This paper reports the features of this construction work and the situation of the No. 2 incinerator operations.

Woody Biomass Power Generation Plant and Combustion Gas Purification Facility Delivery Report
(*Energy Engineering Dept. 2, **Plant Service Dept. 2)


Sara Inc. operates a worldʼs cutting-edge facility horticulture business that combines biomass power generation with vegetable cultivation in the largest semi-closed greenhouses in Japan. In this business of Sara Inc., our company has constructed a biomass power generation plant adjacent to the greenhouses. This plant uses renewable energy and no fossil fuel, and includes a combustion gas purification facility to remove the harmful components from the combustion gas produced by the biomass power generation plant. This facility supplies the electric power and heat necessary for the greenhouses and supplies the carbon dioxide necessary for the photosynthesis activity to promote crop growth. This paper reports the outline of the biomass power generation plant and combustion gas purification facility delivered by our company, the operation results and the features of the O&M work.