Emission of PM2.5-Bound Polycyclic Aromatic Hydrocarbons from Biomass and Coal Combustion in China

Field measured PAH emissions from diverse sources in China are limited or even not available. In this study, the PM2.5-bound PAH emission factors (EFs) for typical biomass and coal combustion in China were determined on-site. The measured total PAH EFs were 24.5 mg/kg for household coal burning, 10.5–13.9 mg/kg for household biofuel burning, 8.1–8.6 mg/kg for biomass open burning, and 0.021–0.31 mg/kg for coal-fired boilers, respectively. These EF values were compared with previous studies. The sources profiles of PAHs for four sources were developed to use in chemical mass balance receptor modelling. BaP equivalent EFs (EFBaPeq) were calculated to evaluate PAH emission toxicity among different combustion sources, and were 6.81, 2.94–4.22, 1.59–3.62, and 0.0006–0.042 mg/kg for those four types of sources, respectively.

Revealers, Skeptics, and Witnesses: Advancing a Witness Methodology in Ethnographic Theology and Ethics

Drawing on original ethnographic fieldwork with a Christian environmental initiative in Appalachia and Alabama, this article argues that moral theologians should conceive of ethnography as witnessing witnesses to aid and multiply witnesses. An ethnographic ‘witness methodology’ is contrasted with two other approaches that the author calls revealer and skeptic methodologies. This witness methodology is developed primarily by analyzing a creation care organization’s practice of citizen science in places devastated by coal mining and coal burning. The author develops the concept of witness by reflecting on his role in helping the organization develop a slogan to describe their work and how this slogan encapsulates their citizen science practice. Though developed primarily in conversation with the author’s fieldwork, the proposed witness methodology is also supported through dialogue with Scripture, Christian ethics, and cultural anthropology.

Improvement of sustainability and efficiency of urban heating using coal-water slurry fuel

Coal-water slurry fuel is coming into use in heat generation facilities as an alternative to natural gas and heavy oil. The main advantage of coal slurry is its cost efficiency. Our project is devoted to improvement of heat generation using coal-water slurry fuel instead of investing in new construction of coal-burning boiler houses. As an example, we considered implementing this project in the city of Leninsk-Kuznetsky, Russia. The project implies partial burning of coal slurry along with conventional coal burning. This solution is cost efficient and environmentally friendly yet not requiring major heat generation equipment replacement or renovation. The total cost efficiency of the suggested project is estimated at least as 1.1 billion rubles per year.

Gas Emissions from Mixed Coal-Biomass Derived Fuel Burned in an Industrial Boilers

Textille industry consumes huge amount of coal to operate their boiler. At the same time, the company generated huge amount of bottom ash from the boiler operation and it is considered as hazardous waste. PT. X has been attempting to reuse bottom ash mixed with solid waste compost to generate biofuel named as biomass coal fuel (BCF) briquettes as co-fuel for boiler combustion. This study conducted two boiler combustion experiments: i) co-firing boiler operation with 90% coal and 10% of BCF, and ii) 100% of coal. The SO2 and NO2 emissions were measured from the two experiments. The emission test was carried out using the MRU Optima 7 which is equipped by an electrochemical sensor, combined with an extraction probe to be inserted into the stack. From the emission test results, the SO­2 concentration of 100% of coal burning was 150 mg/Nm3. SO2 concentration of coal fuel with a substitution of 10% BCF was 498.8 mg/Nm3. The NO2 concentration from 100% coal combustion was 174.2 mg/Nm3 while from mixed fuel combustion was 370.3 mg/Nm3. Using BCF as an aggregate for coal combustion did not bring in lower emissions of SO2 and NO2. Emission factor for SO2 from 100% coal combustion is 6.295 g/kg while for coal fuel with a substitution of 10% BCF is 31.09 g/kg. NO2 emission factor from 100%, coal burning is 7.31 g/kg while the emission factor of NO2 in coal fuel with a substitution of 10% BCF is 23.31 g/kg.

Gas Emissions from Mixed Coal-Biomass Derived Fuel Burned in an Industrial Boilers

Textille industry consumes huge amount of coal to operate their boiler. At the same time, the company generated huge amount of bottom ash from the boiler operation and it is considered as hazardous waste. PT. X has been attempting to reuse bottom ash mixed with solid waste compost to generate biofuel named as biomass coal fuel (BCF) briquettes as co-fuel for boiler combustion. This study conducted two boiler combustion experiments: i) co-firing boiler operation with 90% coal and 10% of BCF, and ii) 100% of coal. The SO2 and NO2 emissions were measured from the two experiments. The emission test was carried out using the MRU Optima 7 which is equipped by an electrochemical sensor, combined with an extraction probe to be inserted into the stack. From the emission test results, the SO­2 concentration of 100% of coal burning was 150 mg/Nm3. SO2 concentration of coal fuel with a substitution of 10% BCF was 498.8 mg/Nm3. The NO2 concentration from 100% coal combustion was 174.2 mg/Nm3while from mixed fuel combustion was 370.3 mg/Nm3. Using BCF as an aggregate for coal combustion did not bring in lower emissions of SO2 and NO2. Emission factor for SO2 from 100% coal combustion is 6.295 g/kg while for coal fuel with a substitution of 10% BCF is 31.09 g/kg. NO2 emission factor from 100%, coal burning is 7.31 g/kg while the emission factor of NO2 in coal fuel with a substitution of 10% BCF is 23.31 g/kg.