Acidic aerosols resulting from gas flaring and refinery operations in the Niger Delta are a serious environmental and public health concern. Several thousand tons of flue gas components (dust particles, SO<sub>x...Acidic aerosols resulting from gas flaring and refinery operations in the Niger Delta are a serious environmental and public health concern. Several thousand tons of flue gas components (dust particles, SO<sub>x</sub>, CO and NO<sub>x</sub>) are released into the atmosphere by flaring billions of cubic meters of natural gas, refining and volatilizing the spilt oil. Heat wave is generated by flaring travels several meters away from flare points, destroying crops, farm lands, exotic species that are hunters delight while causing extinction of fragile soil flora and fuana. The occurrence of acid rain in the region implies that the natural receptors of the area are the final recipient of land and atmospheric pollutants. In effect, the water needs and public health of the populace are greatly impeded. Nitric and sulphuric acids are regarded as the sole contributors of nitrate and sulphate in precipitation influenced by combusted hydrocarbons: fine nitrate aerosols that dissolve in rain water are conversion products of NO<sub>2</sub> that arise from flaring, power plants and motor vehicles. Scientific evidence has shown that rain water and surface water quality in the Niger Delta can accentuate the poor health burden, and may be perpetuated through generations unborn. Diagnostic health risk assessment has revealed that drinking nitrate contaminated water may be associated with spontaneous miscarriage, ectopic pregnancy, adult malignant lymphomas, soft tissues sarcomas, cancers and lesions with added health burden associated with heavy metals and other ions. All these pose public health emergency and may significantly entrench health risk for generations to come. Therefore, this manuscript is intended to close certain gaps that were not covered by toxicological information and available data on environmental and food contamination and human internal exposure: it will serve as a continuous reminder and a useful guide to public health policy makers, workers and community based physicians.展开更多
Protein wastes (feathers, goat hair) and cellulosic wastes (corn cob, coconut husks) were collected, washed with detergent solution, thoroughly rinsed and sun dried for 2 days before drying in an oven and then ground,...Protein wastes (feathers, goat hair) and cellulosic wastes (corn cob, coconut husks) were collected, washed with detergent solution, thoroughly rinsed and sun dried for 2 days before drying in an oven and then ground, half of ground material was carbonized at a maximum temperature of 500?C after mixing with H2SO4.The carbonized parts were pulverized;both carbonized and uncarbonized sorbents were sieved into two particle sizes of 325 μm and 625 μm using mechanical sieve.1.5 g protein wastes and cellulosic wastes were each used to mop up spilled crude oil, diesel, kerosene and petrol (separately before combining) by encasing them in a sac like boom of 2cm x 2cm x 1cm dimension so as to determine the efficacy of waste sorbents in cleaning hydrocarbon spills. Results of Tables 1(a)-4(a), 1(b)-4(b) and 5-8 shows that the sorbents mopped, desorbed and retained an average of more than 500%, 350% and 300% of their weight of the hydrocarbon sorbates within average of 90 mins contact time, the volume of sorbates mopped up increased significantly when equal weight of activated and unactivated sorbents were combined, the results of equal combination of activated and unactivated sorbents at each particle size and contact time were compared with that of calculated values, high percentage retention observed were a function of mechanism of absorption/adsorption. Each sorbent have a distinct feature that enhances its mopping ability. Large volumes of the hydrocarbon liquids were recovered by mere pressing, the sorbates were mopped up in the order;crude oil > diesel > kerosene > petrol. Protein sorbents with oleophilic and aqua phobic properties absorbed more of all the hydrocarbon liquids than cellulosic sorbents at any particle size and contact, the later tend to be more abundant and therefore cost effective;it was observed that both carbonized and uncarbonized sorbents are good hydrocarbon mops and therefore good alternative to synthetic polyurethane foam already in use. Combination, particle size, activation of sorbents, contact time, viscosity and chain length of hydrocarbon determined the amount of sorbates absorbed/adsorbed, recovered or retained. The residual leachable oil (kerosene) in the sorbents were below 5% and does not constitute serious environmental menace when left in an open dump to decay being biodegradable waste, but a brighter application is that the waste sorbent can be used in making logs as alternative to fire wood or in making particle board for furniture.展开更多
文摘Acidic aerosols resulting from gas flaring and refinery operations in the Niger Delta are a serious environmental and public health concern. Several thousand tons of flue gas components (dust particles, SO<sub>x</sub>, CO and NO<sub>x</sub>) are released into the atmosphere by flaring billions of cubic meters of natural gas, refining and volatilizing the spilt oil. Heat wave is generated by flaring travels several meters away from flare points, destroying crops, farm lands, exotic species that are hunters delight while causing extinction of fragile soil flora and fuana. The occurrence of acid rain in the region implies that the natural receptors of the area are the final recipient of land and atmospheric pollutants. In effect, the water needs and public health of the populace are greatly impeded. Nitric and sulphuric acids are regarded as the sole contributors of nitrate and sulphate in precipitation influenced by combusted hydrocarbons: fine nitrate aerosols that dissolve in rain water are conversion products of NO<sub>2</sub> that arise from flaring, power plants and motor vehicles. Scientific evidence has shown that rain water and surface water quality in the Niger Delta can accentuate the poor health burden, and may be perpetuated through generations unborn. Diagnostic health risk assessment has revealed that drinking nitrate contaminated water may be associated with spontaneous miscarriage, ectopic pregnancy, adult malignant lymphomas, soft tissues sarcomas, cancers and lesions with added health burden associated with heavy metals and other ions. All these pose public health emergency and may significantly entrench health risk for generations to come. Therefore, this manuscript is intended to close certain gaps that were not covered by toxicological information and available data on environmental and food contamination and human internal exposure: it will serve as a continuous reminder and a useful guide to public health policy makers, workers and community based physicians.
文摘Protein wastes (feathers, goat hair) and cellulosic wastes (corn cob, coconut husks) were collected, washed with detergent solution, thoroughly rinsed and sun dried for 2 days before drying in an oven and then ground, half of ground material was carbonized at a maximum temperature of 500?C after mixing with H2SO4.The carbonized parts were pulverized;both carbonized and uncarbonized sorbents were sieved into two particle sizes of 325 μm and 625 μm using mechanical sieve.1.5 g protein wastes and cellulosic wastes were each used to mop up spilled crude oil, diesel, kerosene and petrol (separately before combining) by encasing them in a sac like boom of 2cm x 2cm x 1cm dimension so as to determine the efficacy of waste sorbents in cleaning hydrocarbon spills. Results of Tables 1(a)-4(a), 1(b)-4(b) and 5-8 shows that the sorbents mopped, desorbed and retained an average of more than 500%, 350% and 300% of their weight of the hydrocarbon sorbates within average of 90 mins contact time, the volume of sorbates mopped up increased significantly when equal weight of activated and unactivated sorbents were combined, the results of equal combination of activated and unactivated sorbents at each particle size and contact time were compared with that of calculated values, high percentage retention observed were a function of mechanism of absorption/adsorption. Each sorbent have a distinct feature that enhances its mopping ability. Large volumes of the hydrocarbon liquids were recovered by mere pressing, the sorbates were mopped up in the order;crude oil > diesel > kerosene > petrol. Protein sorbents with oleophilic and aqua phobic properties absorbed more of all the hydrocarbon liquids than cellulosic sorbents at any particle size and contact, the later tend to be more abundant and therefore cost effective;it was observed that both carbonized and uncarbonized sorbents are good hydrocarbon mops and therefore good alternative to synthetic polyurethane foam already in use. Combination, particle size, activation of sorbents, contact time, viscosity and chain length of hydrocarbon determined the amount of sorbates absorbed/adsorbed, recovered or retained. The residual leachable oil (kerosene) in the sorbents were below 5% and does not constitute serious environmental menace when left in an open dump to decay being biodegradable waste, but a brighter application is that the waste sorbent can be used in making logs as alternative to fire wood or in making particle board for furniture.
