DC Water는 4억7천만 달러 규모의 폐기물-에너지 프로젝트를 밝혔다. 이는 신재생에너지를 Blue Plains 플랜트의 에너지 수요 중 1/3의 공급을 위해 폐수처리공정에서 10㎿ 규모의 전력으로 생산되며, 궁극적으로 깨끗한 물을 제공한다.

 

탈수화 시설을 포함하며, 32개의 매끄러운 열적 가수분해 선박, 4개의 콘크리트로 이루어진 80피트 높이의 혐기성 소화조는 각각 380만 갤런의 고체와 제트 엔진 크기의 3개의 터빈이 해당한다.

 

 

 

DC Water has unveiled its $470-million waste-to-energy project that is producing a net 10 megawatts (MW) of electricity from the wastewater treatment process, ultimately providing clean, renewable energy to power about one-third of the Blue Plains plant's energy needs.

 

The facilities include a dewatering building, 32 sleek thermal hydrolysis vessels, four concrete 80-foot-high anaerobic digesters that hold 3.8 million gallons of solids each, and three turbines the size of jet engines. The project, which broke ground in 2011, was only viable through the use of innovative technology never before used in North America -- the CAMBI thermal hydrolysis process -- making Blue Plains the largest thermal hydrolysis installation in the world.

 

Thermal hydrolysis uses high heat and pressure to "pressure cook" the solids left over at the end of the wastewater treatment process. This weakens the solids' cell walls to make the energy easily accessible to the organisms in the next stage of the process -- anaerobic digestion. The methane these organisms produce is captured and fed to three large turbines to produce electricity. Steam is also captured and directed back into the process.

 

Finally, the solids at the end of the process are a cleaner Class-A biosolids product that DC Water uses as a compost-like material. Biosolids products are currently being used around the District for urban gardens and green infrastructure projects. DC Water conducted more than a decade of research before bringing these facilities online. Their world-renowned wastewater research program includes dozens of researchers conducting their Ph.D. and masters theses on DC Water projects.

 

DC Water selected the PC/CDM Joint Venture, which brings together the industry-leading expertise in water treatment facility design and construction of PC Construction and CDM Smith to utilize the design-build delivery method to build the Cambi thermal hydrolysis process at the Blue Plains facility.

 

[출처 = Water World / 2015년 10월 8일]