Pilot plant test of an activated sludge ultrafiltration combined process for domestic wastewater reclamation

Biomass cofiring in existing coal fired boilers has emerged as one of the most prospective technologies in order to address voluntary reduction of green house gases and other emissions, potential portfolio standards, customer service etc. within the context of deregulations. Pilot plant test results have confirmed the potential of biomass cofiring with coal for commercial use. However, being a new and developing technology, there is hardly any tool available for estimation of variation in performance of an existing coal fired boiler due to its retrofitting for biomass cofiring. A predicting tool is developed to estimate this performance variation using available information of pilot plant test results in literature or from data of plant operating with biomass. In order to incorporate future available information, this is developed in a flexible environment of Model Development Kit (MDK) of IPSEpro, a commercially available heat and mass balance program. Development of the models for this predicting tool as well as its limitations and possible future improvement has been discussed in this paper. Some results regarding estimation of change in efficiency, emissions and associated costs using this developed predicting tool has been presented.

Download Full-text

Development of Coal Partial Gasification and Combustion System

Volume 7: Turbo Expo 2004 ◽

10.1115/gt2004-54064 ◽

2004 ◽

Author(s):

Yaoxin Liu ◽

Libin Yang ◽

Mengxiang Fang ◽

Guanyi Chen ◽

Zhongyang Luo ◽

...

Keyword(s):

Conversion Efficiency ◽

Pilot Plant ◽

Sulfur Removal ◽

Test Facility ◽

Molar Ratio ◽

Fuel Conversion ◽

Heating Value ◽

Pilot Plant Test ◽

Plant Test ◽

Partial Gasification

A new system using combined coal gasification and combustion has been developed for clean and high efficient utilization of coal. Following are the processes. The coal is first partially gasified and the produced fuel gas is then used for industrial purpose or as a fuel for a gas turbine. The char residue from the gasifier is burned in a circulating fluidized bed combustor to generate steam for power generation. For having the experimental investigation, a 1MW pilot plant test facility has been erected. Experiments on coal partial gasification with air, and recycle gas have been made on the 1 MW pilot plant test facility. The results show that, with air as gasification agent, the system can produce 4–5MJ/Nm3 low heating value dry gas and fuel conversion efficiency attains 50–70% in the gasifier, and residue 20–40% converted in the combustor and total conversion efficiency in the system is over 90%. In the gasifier, the carbon conversion efficiency increases with the bed temperature and the air blown temperature. CaCO3 has an effective effect for sulfur removal in the gasifier. The sulfur removal efficiency attains 85% with Ca/S molar ratio 2.5. The system can produce 12–14MJ/Nm3 middle heating value day gas by using high temperature circulation solid as heat carrier and recycle gas or steam as gasification media, but the fuel conversion efficiency only attain 30–40% in the gasifier and most of fuel energy is converted in the combustor. CaCO3 has an obvious effect on tar cracking and H2S removal. The sulfur removal efficiency attains 80% with Ca/S molar ratio 2.5.

Download Full-text

Membrane bio-reactor for textile wastewater treatment plant upgrading

Water Science & Technology ◽

10.2166/wst.2005.0091 ◽

2005 ◽

Vol 52 (4) ◽

pp. 91-98 ◽

Cited By ~ 8

Author(s):

C. Lubello ◽

R. Gori

Keyword(s):

Activated Sludge ◽

Pilot Plant ◽

Treatment Plant ◽

Textile Wastewater ◽

Experimental Period ◽

Pilot Scale ◽

Wastewater Reclamation ◽

Textile Wastewater Treatment ◽

Secondary Settling ◽

Solid Liquid

Textile industries carry out several fiber treatments using variable quantities of water, from five to forty times the fiber weight, and consequently generate large volumes of wastewater to be disposed of. Membrane Bio-reactors (MBRs) combine membrane technology with biological reactors for the treatment of wastewater: micro or ultrafiltration membranes are used for solid-liquid separation replacing the secondary settling of the traditional activated sludge system. This paper deals with the possibility of realizing a new section of one existing WWTP (activated sludge+clariflocculation+ozonation) for the treatment of treating textile wastewater to be recycled, equipped with an MBR (76 l/s as design capacity) and running in parallel with the existing one. During a 4-month experimental period, a pilot-scale MBR proved to be very effective for wastewater reclamation. On average, removal efficiency of the pilot plant (93% for COD, and over 99% for total suspended solids) was higher than the WWTP ones. Color was removed as in the WWTP. Anionic surfactants removal of pilot plant was lower than that of the WWTP (90.5 and 93.2% respectively), while the BiAS removal was higher in the pilot plant (98.2 vs. 97.1). At the end cost analysis of the proposed upgrade is reported.

Download Full-text