Technical informationTECHNOLOGY

VOL.14 NO.1 (published in Sep-2006)

Photo in Cover :Biopower Katsuta Power Plant
VOL.14 NO.1 (published in Sep-2006)
The Transition, the Present Condition and View in Future of the Control Technology for the Incineration Plant
(Electrical and Instrumentation Dept.)


Recently "Environmental preservation" including global warming is debated all over the world and the world is going towards recycle societies. In an incineration plant, it is demanded that energy shall be recovered high efficiently by, when burning the refuse without harmful contents in the flue gas or ash. On the other hand, instrumentation and control technology for plant operation has been improved and developed such as by atomization automation or computerization. Furthermore it has been made dramatic progress in IT technology and it gives various possibilities to instrumentation and control technology. The transition, the present condition and view in future for the incineration plant are introduced in on this report.

Development of Sewage Sludge Gasification System -Report No.2
-Report on Demonstration Test of Power Generation Using Gas Derived from Sewage Sludge-
Akihiro SAIGA*,Keiji TATSUMI*,Kazuki HAYASHI*and Masaki HONDO**,Jun SAITO**
(*Combustion and Core Technology Development Dept.
**Technology Research Institute, Tokyo Gas Co., Ltd.)


Using a pilot-scale testing plant, we have been developing a gasification system that utilizes the energy contained in the sewage sludge without disturbing its treatment process. It was adopted as a co-development project with NEDO for the fiscal year 2004, and a demonstration plant was built in that period with 15 ton/day (80% moisture basis) throughput using a gas engine generator with the power generating capacity of 200~260kW. The demonstration test of gasification went underway in the fiscal year 2005 during which our efforts were concentrated in studying the operational characteristics of all equipment. The gasification test involved the total of 450 tons. We achieved the carbon conversion ratio and the cold gas efficiency of roughly 90% and 60%, respectively, while the lower heat value of the gas was approximately 4~5MJ/m3N at the furnace outlet. Power generation test was also conducted using the gas engine, resulting in the high generation efficiency of better than 32% of the heat input to the gas engine. This article reports on the outline of the demonstration plant and the test results obtained during the fiscal year 2005.

Refinement of Biomass Gasification Gas
Hitoshi HARADAand Takaaki SHINODA
(Research Center)


Biomass gasification gas derived from CFB (Circulating Fluidized-Bed) gasifier that contains a few impurities that may cause some troubles must be refined before being used.

In this report, we discuss about a refinement scheme of the biomass gasification gas that may apply for biomass gasification-hybrid system of generating electricity and synthesizing methanol. The refinement process consists of high temperature gas filtration, catalytic tar reforming, wet gas scrubbing, desulfurizing agent and hydrogenation catalyst.

We examined the refinement process for woody biomass gasification gas at the bench test apparatus. In those experiments, the refinement process could eliminate sulfide under 0.1 ppm-dry and unsaturated aliphatic hydrocarbons under 0.01%-dry from woody biomass gasification gas, and we could collect 93~95% methanol. Reaction yield of methanol had not fallen during the total of 20 hours.

Development of Methanol Synthesis Process from Biomass
Muneharu FUJIKAWA,Kazuhiro SATO,Hiroki YAMASAKIand Takaaki SHINODA
(Research Center)


In this research we have developed the technology that synthesized most effectively methanol from the biomass gasification gas by the one through process, as a gas-to-liquid fuel technology for a decentralized plant.

We equipped the bench testing apparatus of amount 4m3N/h of the processing gas, and executed the methanol synthesis test from the biomass gasification gas.

We could synthesize the methanol of the purity 95% from the gas obtained by the woody biomass gasification process. It reports as the first report of this research.

Report on Futtsu Clean Center
Kengo KISHIand Jun-ichi BABA
(Sewerage Engineering Dept.)


In this report we introduce Futtsu Clean Center, night soil treatment plant that was completed at the end of March 2006.

Night soil and johkasou sludge collected in Futtsu city are dumped into a concrete tank, treated both biologically and chemically (coagulation-precipitation) and final effluent is discharged into sewerage.Screw press dehydrator dewaters waste sludge from these treatments and dewatered sludge is carried out to incineration plant.

We conducted a performance test in almost usual condition, and results of all items met the requirement such as effluent quality, water content of dewatered sludge and odor removal efficiency.

Pyrolysis Gas Melting System Operation Report of the Environmental Resources Gallery
(Environmental Design Dept.)


The environmental resources gallery for the Kakegawa & Kikugawa Cities Sanitation Control Association becomes the 3rd gasification and melting plant made by our company for municipality.

Delivery was completed on August 31, 2005 through the test run from March 2005, and it has been continuing good operation until now.

In this facility, it uses of sodium series reactant as flue gas processing chemical, rationalization of melting furnace form, simplification of the apparatus composition of carbon blowing equipment and adoption of film type wastewater treatment and also be able to establish operation which leads to improvement in economical efficiency.

A New Exhaust-gas Treatment System Using Ceramic Filters and a Sodium Reactant Applied for MSW Pyrolysis and Melting Plant
Masaaki KURATA*,Masakazu TAGUCHI*,Norio MAEDA*,Tomonori ASO**,
Toru MIYAKAWA***and Daisuke AYUKAWA****
(*Mechanical Design & Engineering Dept.**Energy and environmental Development Dept.
***Environmental Design Dept.****Environmental Engineering Dept.)


We have developed a new exhaust-gas treatment system using ceramic filters and a sodium reactant that remove particulates and acid gases in the temperature range of 300℃. This system has been applied to a kiln-type pyrolysis gas melting plant for MSW (70 ton / 24 h × 2 units). As the heat source for the pyrolysis process, the exhaust gases from the combustion of the pyrolysis gases generated by the pyrolysis process are used in this plant. This new cleaning system has been applied to this exhaust gases in the temperature range of 300℃ for the removal of acid gases and the particulates. The filter element is made of ceramic (produced by Kyocera Co.) and is stronger than those made of fabrics.

This plant began an operation with load in June of 2005. The dust-collection efficiency of the ceramic filter has been better than 99.8% with the pressure loss of roughly 2.2kPa at the filtration speed of 1.5m/min. To prevent the corrosion of the heating pipes of the pyrolysis drum where the combustion exhaust gases flow, the HCl concentration after the exhaust treatment was set at 15 ppm by controlling the reagent feed rate, enabling a stable operation within the corrosion-free state.

Overview of Biopower Katsuta Power Plant
Keiji MUKAI,Hisaaki HIDAKAand Takayuki HATAGI
(Energy Engineering Dept.)


The biomass energies play an important role among the new energies. They are expected to be re-used in terms of global-warming prevention and energy-security reservation, and, therefore are enhanced by the government.

Under such circumstances, Biopower Katsuta Power Plant, which was established in July, 2006, generates 4,900 kW electricity and sells 4,100 kW (after subtracting house load) to the PPS. It utilizes the wood-biomass fuel (150 tons/day), which arises as a result of scrapped house (not appropriate for material recycles).

In this section, plant outline and operation result of the wood-biomass-fluidized-bed boiler power plant is reported.