ENG  Vol.7 No.10 , October 2015
Analysis of Temperature Profiles and Cycle Time in a Large-Scale Medical Waste Incinerator
Abstract: Temperature profiles and cycle times in a large-scale medical waste incinerator installed in a referral hospital were used to assess the performance and functionality of incinerator. The study was conducted using data collected from 8 cycles per days for 67 days. For proper combustion and destruction of toxic components in the primary chamber and destruction of pollutants and toxic components in the flue gas, it is desired to reach the maximum temperature in the chambers faster and maintain this maximum temperature for an extended time interval. The primary and secondary temperatures T1 and T2, respectively, were recorded at an interval of one minute for different cycles. Different amounts of wastes with varying proportions of sharps and other wastes were loaded into the incinerator and temperature profiles recorded. The analysis shows that the incinerator works at primary temperature less than the required recommended by manufacturer while the secondary chamber operates between 600 and above 950, although higher temperatures up to 1020 were observed. The average load preparation time was observed to be 14.6 minutes, while the chamber preheating time before daily initial loading was 25.45 minutes. Both temperature profiles were observed to have similar shapes for all combustion cycles studied, except when incinerator malfunctioning occurred. The average cycle time was established to be 32.7 minutes and 28.97 minutes based on time to drop to 550 after the maximum temperature and loading time intervals, respectively, although longer cycle times were observed. Temperature drop in both combustion chambers as a result of waste charging was observed in the interval of 5 minutes. The chamber heating rate was observed to decrease exponentially with time during both preheating and incineration operation.
Cite this paper: Matee, V. and Manyele, S. (2015) Analysis of Temperature Profiles and Cycle Time in a Large-Scale Medical Waste Incinerator. Engineering, 7, 717-732. doi: 10.4236/eng.2015.710063.

[1]   Santoleri, J.J. (1985) Design and Operating Problems of Hazardous Waste Incinerators. Environmental Progress, 4, 246-251.

[2]   Manyele, S.V. and Kagonji, I.S. (2012) Analysis of Medical Waste Incinerator Performance Based on Fuel Consumption and Cycle Times. Engineering, 4, 625-635.

[3]   Kagonji, I.S. and Manyele, S.V. (2010) Analysis of the Measured Medical Waste Generation at Amana and Ligula Hospitals Using Statistical Methods. African Journal of Environmental Science and Technology (AJEST), 5, 815-833.

[4]   Singh, S. and Prakash, V. (2007) Toxic Environmental Releases from Medical Waste Incineration: A Review. Environmental Monitoring, 132, 67-81.

[5]   Manyele, S.V. (2004) Medical Waste Management in Tanzania. Current Situation and the Way Forward. African Journal of Environmental Assessment and Management (AJEAM), 8, 74-99.

[6]   Manyele, S.V. and Mujuni, C.M. (2010) Current Status of Sharps Waste Management in Lower Level Health Facilities in Tanzania. Tanzania Health Research Journal, 12, 257-264.

[7]   Blackman Jr., W.C. (1996) Basic Hazardous Waste Management. 2nd Edition, Lewis Publishers, Boca Raton.

[8]   Oppelt, E.T. (2007) Incineration of Hazardous Waste—A Critical Review. Journal of the Air Pollution Control Association, 37, 558-586.

[9]   Kaseva, M.E. and Mato, R.R.A.M. (1999) Critical Review of Industrial and Medical Waste Practices in Dar es Salaam City. Resource Conservation and Recycling, 25, 271-287.

[10]   Manyele, S.V. and Anicetus, H. (2006) Management of Medical Waste in Tanzanian Hospitals. Tanzania Health Research Bulletin, 8, 177-182.

[11]   Allsopp, M., Costner, P. and Johnston, P. (2001) State of Knowledge of the Impacts of Waste Incinerators on Human Health. Environ Science and Pollution Research, 8, 141-145.

[12]   Gidarakos, E., Petrantonaki, M., Anastasiadou, K. and Schramm, W. (2009) Characterization and Hazard Evaluation of Bottom Ash Produced from Incinerated Hospital Waste. Journal of Hazardous Materials, 172, 935-942.

[13]   Sharifah, A.S.A.K., Abidin, H.Z., Sulaiman, M.R., Khoo, K.H. and Ali, H. (2008) Combustion Characteristics of Malaysian Municipal Solid Waste and Predictions of Air Flow in Rotary Kiln Incinerator. Journal of Material Cycles and Waste Management, 10, 116-123.

[14]   Kagonji, I.S., Manyele, S.V. and Mrisho, J. (2011) Assessment of a Double Chamber Incinerator Performance Based on Ash Characteristics. Engineering, 3, 1045-1053.