Aspen plus simulation of the paint waste sludge gasification process
Abstract
The existence of heavy metals in paint sludge together with other forms of toxic chemicals make it hazardous and therefore not good for disposal into the environment. This is because it results into health effects to both plants and animals around the disposal area. These include; diarrheal diseases that arise due to water contamination. Paint sludge is categorized as a hazardous waste and the factors responsible for this include; heavy metals and volatile organic compounds. This therefore, calls for the need to convert it into a more useful product. However, conversion of paint waste sludge is dependent on its physical and chemical characteristics. Paint sludge is being characterized by measurement of different parameters which include; proximate analysis and thermal degradation, chemical analysis, measurement of calorific value, specific heat capacity and ultimate analysis of paint waste sludge. Gasification is the reaction of carbonaceous material with an oxygen-based reagent, usually at temperatures above 800°C, to produce synthesis gas. Gasification does not proceed successfully when there is a high flow rate of air into the reactor. This is due to the fact that gasification takes place under mild air conditions that do not allow for complete combustion. As a result, as the flow rate of paint waste sludge increases, the amount of carbon monoxide in the paint waste sludge generated increases while the amount of carbon dioxide produced decreases. This makes the syngas produced to be of higher quality and hence appropriate for usage. In conclusion, higher flow rates of paint waste sludge result into lower values of hydrogen to carbon monoxide ratios, making the paint waste sludge generated to have higher proportions of carbon monoxide gas with minimal hydrogen gas generated. Separation of the syngas from the solid by products across the cyclone is dependent on the particle size distribution to which the cyclone is designed.