Browsing by Author "Peiris, S"

Now showing 1 - 7 of 7

item: Thesis-Abstract
Cleaner production options for skim rubber industry - a case study
Yasaratna, PDTN; Wijeyekoon, SLJ; Peiris, S
Rubber processing factories generate large amount of wastewater containing organic pollutants and various process chemicals. Rubber processing factory effluents exhibit high BOD (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand), ammonia, and suspended solid concentrations. Except for a few, most rubber processing factories in Sri Lanka do not adequately treat the effluents before discharge either due to high cost of treatment or use of inefficient methods for treatment. Due to the low operating margins of this vital industry, that utilizes a waste product as raw material, an introduction A of expensive pollution control methods would lead to the collapse of the industry. In centrifuging plants the serum water contains 2.5% to 10.0% m/m.(I) dry rubber. Direct coagulation of this skim latex is not easy, because the colloid stability is enhanced by the high content of ammonia and protein containing substances, and by the small size of the dispersed rubber particles. One method of coagulation is by the addition of sulphuric acid where the skim is left to coagulate spontaneously. Then the coagulum is processed by conventional means, and made in to thick crepe. The technology used in the selected factory for the case study, the production procedure is in primitive stage and this result in low productivity with high environmental damage. The industry discharges large volume of waste water and effluents consisting of 34 000 litres of serum and 4 000 litres of wastewater per day. Though the company has a large Treatment plant, the effectiveness of it is totally inadequate due its high retention time. Few methodologies were used to find out the environmental damage by this factory, quantify the wastes and ways of maximum utilization of resources. Walk through audits; develop process flow charts, materials balance sheet, chemical analysis of raw material and the effluent and brainstorming are such methodologies. The application of Cleaner Production (CP), apart from reducing pollution load brings in many other benefits to this type of industry, which include resource conservation, improvement in work environment, product quality improvement etc. Cleaner production is not only concerned with technology, but also with management, labour, organization and health and safety. Cleaner production solutions will help to improve the industry's financial bottom line and mitigate environmental damage through helping the industry to survive. Fifteen cleaner production options were identified during the study. Waste free latex, de-arnrnoniation, avoidance o~ntaminates, control use of chemicals, improvement of coagulation process, technology improvement for skim separation, resource recovery, repair and maintenance, good house keeping, better storing of finished goods, modifying the air drying process, introduce proper drainage system for wastewater flowing, change the power generating system, and better scheduling are the identified CP options in the factory. Based on technical feasibility, financial viability and environmental desirability, an overall qualitative analysis was carried out for these options. According to the analysis the Proper mixing of skim latex with chemicals (Sulphuric acid), minimize rubber in waste streams, mechanized the skimming process, good house keeping practices (Introduce proper drainage system for w. water ,separate and reuse water and storing finished goods )and de-ammoniating options were prioritised. The proposed pollution prevention ana pollution control measures would help to improve the environmental performance of skim rubber processing factories and grant resource conservation benefits to the industry.
item: Conference-Full-text
Environmental management options for skim rubber industry
(2005) Yasaratna, PDTN; Wijeyekoon, SLJ; Peiris, S
Natural rubber processing factories generate large amount of wastewater containing organic pollutants and various process chemicals. The effluents exhibit high BOD, COD, NH4+-N and suspended solid concentrations. The discharge of untreated effluents into streams or paddy fields result in the emission of obnoxious odour and low pH levels. The acidic effluent is found to cause damage to crops especially to paddy and coconut. Except for a few, most rubber processing factories do not treat the effluent prior to disposal due to high capital and recurrent costs involved for end of the pipe treatment. Therefore sustainable environmental management dictates the adoption of Cleaner Production (CP) strategies to meet environmental regulations and reduce treatment costs.
item: Conference-Full-text
Exploring the facilities management education needs in Sri Lanka
(Ceylon Institute of Builders - Sri Lanka, 2023-07-21) Sridarran, P; Jayakodi, S; Peiris, S; De Silva, N; Lai, JHK; Rathnayake, U; Dissanayake, P
Facilities Management (FM) is a multidisciplinary profession at the core of building operations management. As such, it requires a wide range of skills that differ significantly from region to region due to variable industry sizes, maturity levels, characteristics of building stocks and services, and occupant cultures. Consequently, it is essential to cultivate the necessary knowledge and skills to produce competent FM professionals to cater to the demand of the FM industry. Worldwide, various professional bodies have specified essential competencies for the FM profession. This study aims to reveal the current state of such competencies in the FM industry in Sri Lanka. Accordingly, a scrupulous literature review was conducted to identify the FM competencies. Twelve competency attributes germane to the Sri Lankan context were identified, and subsequently, a web-based questionnaire survey was conducted to analyse their importance and competence levels. The mean ratings were calculated using the received responses and were used to develop an Importance-Competence Analysis (ICA) matrix. The results indicated that ‘operations and maintenance’, ‘leadership’ and ‘technology’ are the prioritised competencies that need improvements through appropriate education and training.
item: Conference-Extended-Abstract
Forecasting critical dry spell lengths in anamaduwa
(2010) Mathugama, SC; Peiris, S
Series of critical dry spell lengths in 56 years in Anamaduwa are analysed to predict the length of critical dry spells Both linear and nonlinear lime series approaches are tried to identify the best Jilted model By comparing various statistical indicators, bilinear model with auto regressive errors of order four is found to be the best model lo lit die critical dry spell lengths.
item: Conference-Full-text
Modeling ageing population (60+ years) in Sri Lanka
(Department of Architecture, University of Moratuwa, Sri Lanka, 2017-10-20) Jayatilake, A; Peiris, S; Wijesundara, J; Dayaratne, R
Population ageing is an universal phenomenon and it is expected to be among the most prominent global demographic trends of the 21st century. In Sri Lanka there was a rising trend of ageing population throughout the past years and has recorded the highest number of agers within South Asia. However, no sound statistical or mathematical models were developed to project ageing population in Sri Lanka. Using the population aged 60 years and above in Sri Lanka during 1950-2016, three types of statistical models: (i) ARIMA (0, 2, 1), (ii) exponential trend model, and (iii) double exponential smoothing model were developed. The models were compared using various statistical indicators and some statistical diagnostics tests. The comparison was done for both training set as well as validation set. Among these models the double exponential smoothing model was found as the best fitted model. According to the forecast derived from the best fitted model, it was found that the increasing trend of ageing population in the country will continue in the future and there will be approximately 2,936,000 ageing population in Sri Lanka in 2020. The information obtained this study is beneficial for planners and decision makers in the government sector and other relevant organizations to cater the needs of the increasing agers in the future of Sri Lanka.
item: Conference-Abstract
Modeling ageing population (60+years) in Sri Lanka
Jayatilake, A; Peiris, S
Population ageing is an universal phenomenon and it is expected to be among the most prominent global demographic trends of the 21st century. In Sri Lanka there was a rising trend of ageing population throughout the past years and has recorded the highest number of agers within South Asia. However, no sound statistical or mathematical models were developed to project ageing population in Sri Lanka. Using the population aged 60 years and above in Sri Lanka during 1950-2016, three types of statistical models: (i) ARIMA (0, 2, 1), (ii) exponential trend model, and (iii) double exponential smoothing model were developed. The models were compared using various statistical indicators and some statistical diagnostics tests. The comparison was done for both training set as well as validation set. Among these models the double exponential smoothing model was found as the best fitted model. According to the forecast derived from the best fitted model, it was found that the increasing trend of ageing population in the country will continue in the future and there will be approximately 2,936,000 ageing population in Sri Lanka in 2020. The information obtained this study is beneficial for planners and decision makers in the government sector and other relevant organizations to cater the needs of the increasing agers in the future of Sri Lanka.
item: Article-Full-text
Smart retrofitting for existing buildings
(Elsevier, 2023) Peiris, S; Lai, JHK; Kumaraswamy, MM; Hou, H
Transforming ordinary buildings into smart building (SB)s, considered as ‘smart retrofitting (SR)’, requires retrofit works that involve smart technology applications. Given the limited knowledge about the SR concept, a systematic literature review was conducted using a mixed methods approach. Following the ‘Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)’ framework, which is a well-recognized comprehensive reporting guideline for systematic reviews, SR-related literature was first identified from ‘Scopus’ and ‘Web of Science’. A bibliometric analysis of the identified literature revealed that the past research predominantly focused on energy efficiency and occupant comfort while social and legal issues were underexplored. A further, qualitative review of the shortlisted literature unveiled the SR research gaps and six future research areas: (1) smart retrofit performance evaluation, (2) SR applications for building envelope optimization, (3) renewable energy integration through SR applications, (4) SR applications for demand side management, (5) stakeholder engagement in SR, and (6) planning for effective SR implementation. Outcomes synthesized from this study include a framework consolidating the review findings and a mapping exhibiting the nexus of future research directions, which serve to facilitate and catalyze expected efforts for realizing SBs.