Food waste generation in a university and the handling efficiency of a university catering facility-scale automatic collection system

Purpose This study aims to evaluate the generation of food waste in a university and the handling efficiency of an automatic waste collection system. Design/methodology/approach The quantity of food waste generated and collected from a university canteen was surveyed. The food waste handling efficiencies using manual collection strategy and automated food waste collection system were determined by the density of food waste. Life-cycle costing analysis was done to evaluate the economic impacts of various food waste collection methods. Findings As compared with the manual collection approach, the automatic system can improve the food waste handling efficiency by 30% (from 0.01 to 0.007 bin kg−1) and reduce the water use by 20% (from 0.512 to 0.406 L kg−1); however, it also consumes 4.4 times more energy (from 0.005 to 0.027 kWh kg−1). Under ideal system operation, the 10-year cost of food waste collection was significantly reduced from $3.45 kg−1 in the manual collection to $1.79 kg−1, and the payback period of the system collection was 1.9 years without discount. Practical implications The outcomes of this study show that an automatic food waste collection system is feasible, and it is recommended for small- and medium-sized catering facilities (e.g. canteens and food courts) to improve food waste handling efficiency. This study also provides useful reference data of automatic food waste collection systems for planning food waste management programs for catering facilities. Originality/value To the best of the authors’ knowledge, this is the first study to evaluate the waste handling efficiency, operational expenditure and life-cycle cost of a small-scale automatic food waste collection system.

Submersible Pump with Line Shaft Pump in Shallow Water, Optimum Selection for Offshore Application in the Oil & Gas Industry

Seawater is an essential fluid used in various process circuits, such as cooling, reinjection into the wells and utilities, etc., in the offshore oil and gas industry. Vertical pumps facilitates with lifting seawater to the platform. This study investigates and compares two pump alternatives that has been widely used in oil and gas industry for seawater lift application: Vertical line-shaft pump and Electrical submersible pump. Existing seawater lift pump operating parameters are used as the basis of this study. The pump that is considered for the study has a flow rate of 3415 US GPM (776 m3/hr.) with a total head of 250 ft. The motor rating is 350 HP. The overall length of the pump is 21 meters. The main methodology used is a Life Cycle Cost Analysis (LCC) where the total cost of ownership of the vertical line-shaft pump and electrical submersible pump were analyzed for a period of 30 years. Furthermore, this research also addresses the operational drawbacks associated with both the pumps. Submersible pumps have higher initial capital investment cost when compared to line-shaft pump of similar capacity and size. The energy consumption cost of submersible pumps are higher mainly owing to lower efficiencies of the motors. The power factor for submersible pumps are lower in relation to line- shaft pumps. One of the main benefits of submersible pumps are their less installation and pump pullout time. Submersible pumps occupies lower space above ground when compared to line-shaft pumps. Additionally, submersible pumps are less noisy and have lower vibration in comparison to line-shaft pumps. This paper aims to provide key information and knowledge for engineers to make prudent decision regarding selection of the most cost effective pump for the seawater lift application with a tangible added cost value to both Capital Expenditures (CAPEX) and Operational Expenditure (OPEX).

Techno-Economic Analysis of the Reclamation of Drinking Water and Valuable Minerals from Acid Mine Drainage

The concept of circular economy in wastewater treatment has recently attracted immense interest and this is primarily fueled by the ever-growing interest to minimise ecological footprints of mining activities and metallurgical processes. In light of that, countries such as the Republic of South Africa, China, Australia, and the United States are at the forefront of water pollution due to the generation of notorious acid mine drainage (AMD). The disposal of AMD to different receiving environments constitutes a severe threat to the receiving ecosystem thus calling for prudent intervention to redress the prevailing challenges. Recent research emphasises the employment of wastewater treatment, beneficiation and valorisation. Herein, the techno-economic evaluation of the reclamation of clean water and valuable minerals from AMD using the Magnesite Softening and Reverse Osmosis (MASRO) process was reported. The total capital expenditure (CAPEX) for the plant is ZAR 452,000 (USD 31,103.22) which includes ZAR 110,000 (USD 7569.37) for civil works on a plant area of 100 m2. The operational expenditure (OPEX) for the pilot is 16,550,000 ZAR (South African Rand) or USD 1,138,845.72 in present value terms (10 years plant life). The plant reclaimed drinking water as specified in different water quality standards, guidelines, and specifications, including Fe-based minerals (goethite, magnetite, and hematite), Mg-gypsum, and calcium carbonate. These minerals were verified using state-of-the-art analytical equipment. The recovered valuables will be sold at ZAR 368/kL (USD 25.32), ZAR 1100/t (USD 75.69), and ZAR 2000/t (USD 137.62) for water, gypsum, and limestone, respectively. The project has an NPV of ZAR 60,000 (USD 4128.75) at an IRR of 26%. The payback period for this investment will take 3 years. The total power consumption per day was recorded to be 146.6 kWh, and 103,288 kWh/annum. In conclusion, findings of this work will significantly contribute to improving the sustainability of the mining sector by proposing economically feasible solutions for wastewater streams treatment, beneficiation, and valorisation.

Synchronized Service Delivers Desired Outcomes

As the subsea well intervention sector ascends from a double-dip downturn, operators are motivated to execute projects with increased agility. By adopting new rationale and supported by strategic partnerships, an enhanced focus on operating efficiency is targeted. This paper discusses how operators can –deliver predictable operational expenditure (opex) results, safeguarding life-of-field economics through routine interventions and robust risk mitigation–align objectives with service providers through technology, strategy, and process–realize value of integrated alliances in the subsea intervention sector. Reliability is the cornerstone on which operational integrity is established. Repeatability is the foundation on which partnerships are formed, forging a synchronized philosophy; pledging operational efficiency as commanded in a dynamic environment; bringing to market a holistic, multileveled, multiskilled solution to subsea interventions; and uniting product and operational experts to evaluate the range of scope requirements selecting fit-for-purpose solutions, delivered with synchronized processes. Here we describe how this approach, coupled with repeatable field-proven product and service reliability and driven by true customer-centric thinking, minimizes operating risk to deliver predictable outcomes. This ethos is demonstrated in action via three case studies that discuss the benefits of combining customer expertise with product and operational specialists during the initiation and planning phases of subsea well intervention projects. The shared examples demonstrate how inculcating a continuous improvement mindset and applying lessons learned to product design, process, and procedures can drive operating efficiency to new levels. Campaigns executed in 2020 by the supplier delivered best-in-class results, exceeding customer expectations. The campaign represented the first fully synchronized service operation on the Q5000 intervention vessel at 90% operating efficiency. In addition, they demonstrated outstanding versatility by outperforming budget on the first deployment of the 15,000 psi intervention riser system (IRS) from the Q4000 intervention vessel. Less than 1% operating nonproductive time (NPT) was attributed to the well access package for the campaign. Sustaining this level of success via collaborative performance management is the next step on the roadmap to ensure this becomes the new normal. Conclusions drawn from customer feedback indicated expectations were surpassed, and that synchronicity is the key that unlocks the door to sustainability in the subsea deepwater intervention sector.

Reduction of Cost and Environmental Impact in the Treatment of Textile Wastewater Using a Combined MBBR-MBR System

A hybrid Moving Bed Biofilm Reactor—Membrane Bioreactor (MBBR-MBR) was developed for the treatment of wastewater from a Spanish textile company. Compared with conventional activated sludge (CAS) treatment, the feasibility of this hybrid system to reduce economic and environmental impact on an industrial scale was conducted. The results showed that, technically, the removal efficiency of COD, TSS and color reached 93%, 99% and 85%, respectively. The newly dyed fabrics performed with the treated wastewater were qualified under the standards of the textile industry. Economically, the values of Capital Expenditure (CAPEX) calculated for the hybrid MBBR-MBR system are profitable because of the reduction in Operational Expenditure (OPEX) when compared with CAS treatment, due to the lower effluent discharge tax thanks to the higher quality of the effluent and the decolorizing agent saved. The result of Net Present Value (NPV) and the Internal Rate of Return (IRR) of 18% suggested that MBBR-MBR is financially applicable for implantation into the industrial scale. The MBBR-MBR treatment also showed lower environmental impacts than the CAS process in the life cycle assessment (LCA) study, especially in the category of climate change, thanks to the avoidance of using extra decolorizing agent, a synthetic product based on a triamine.

Virtual Network Resource Optimization Model for Network Function Virtualization

Network function virtualization (NFV) is a concept aimed at achieving telecom grade cloud ecosystem for new-generation networks focusing on capital and operational expenditure (CAPEX and OPEX) savings. This study introduces empirical throughput prediction model for the virtual network function (VNF) and network function virtualization infrastructure (NFVI) architectures based on Linux kernel. The model arises from the methodology for performance evaluation and modeling based on execution area (EA) distribution by CPU core pinning. EA is defined as a software execution unit that can run isolated on a compute resource (CPU core). EAs are derived from the elements and packet processing principles in NFVIs and VNFs based on Linux kernel. Performing measurements and observing linearity of the measured results open the possibility to apply model calibration technique to achieve general VNF and NFVI architecture model with performance prediction and environment setup optimization. The modeling parameters are derived from the cumulative packet processing cost obtained by measurements for collocated EAs on the CPU core hosting the bottleneck EA. The VNF and NFVI architecture model with performance prediction is successfully validated against the measurement results obtained in emulated environment and used to predict optimal system configurations and maximal throughput results for different CPUs.

Impact of Public Health on Oil Production Operation Expenditure – Case Study: Covid-19 Era Expenses in Nigeria Oil & Gas Industry

Oil price is primarily determined by global supply and demand forces as well as governments policies and action or inaction of institutions like OPEC. However, in recent times, it has become evident that public health is a vital factor influencing demand and in turn oil price. In US, oil price reached a negative value for the first time in history by April 2020. Personnel and public health have been shown to have profound effect on operational expenditure (OPEX) of organizations, this in turn affecting the profitability of such organizations. Extra measures involving cost, had to be taken by organizations all over the world to ensure health and safety of their personnel in their sites. In Nigeria, effect of covid-19 measures for companies were, shut in of production, declaration of force majeure on ongoing contracts, slashing of costs, suspension on evaluation of future projects, profile assets for sale, remote/tele working, etc. Huge costs were also incurred as a part of corporate social responsibility for host communities/states where they operate. The consequential outcome is that there are reports of lower than planned profitability and liquidity positions. This paper examines action taken during this covid crisis and their impact on the financial status of their organizations. Using a quantitative and descriptive research design, an online survey has been used to gather information from respondents from different oil and gas companies of cost incurred by them. Secondary data was also obtained from quarterly reports of some companies of the oil majors to show their profitability comparing Q1-Q4 of 2019 and 2020. The paper also appraises action and inaction by corporate/government bodies to stimulate economic growth and help its personnel/citizenry. An attempt is also made to glean experience and lessons from organization that lived through the periods being examined.

Routing Performance Evaluation of a Multi-Domain Hybrid SDN for Its Implementation in Carrier Grade ISP Networks

Legacy IPv4 networks are strenuous to manage and operate. Network operators are in need of minimizing the capital and operational expenditure of running network infrastructure. The implementation of software-defined networking (SDN) addresses those issues by minimizing the expenditures in the long run. Legacy networks need to integrate with the SDN networks for smooth migration towards the fully functional SDN environment. In this paper, we compare the network performance of the legacy network with the SDN network for IP routing in order to determine the feasibility of the SDN deployment in the Internet Service provider (ISP) network. The simulation of the network is performed in the Mininet test-bed and the network traffic is generated using a distributed Internet traffic generator. An open network operating system is used as a controller for the SDN network, in which the SDN-IP application is used for IP routing. Round trip time, bandwidth, and packet transmission rate from both SDN and legacy networks are first collected and then the comparison is made. We found that SDN-IP performs better in terms of bandwidth and latency as compared to legacy routing. The experimental analysis of interoperability between SDN and legacy networks shows that SDN implementation in a production level carrier-grade ISP network is viable and progressive.

Routing Performance Evaluation of a Multi-Domain Hybrid SDN for its Implementation in Carrier Grade ISP Networks

Legacy IPv4 networks are strenuous to manage and operate. Network operators are in need to minimize the capital and operational expenditure of running network infrastructure. The implementation of Software-defined networking (SDN) addresses those issues by minimizing the expenditures in the long run. Legacy networks need to integrate with the SDN networks for the smooth migration towards the fully functional SDN environment. In this paper, we compare the network performance of the legacy network with the SDN network for IP routing in order to determine the feasibility of the SDN deployment in the Internet Service provider (ISP) network. The simulation of the network is performed in the Mininet test-bed and the network traffic is generated using distributed Internet traffic generator. Open network operating system is used as a controller for the SDN network in which SDN-IP application is used for IP routing. Round trip time, bandwidth, and packet transmission rate from both SDN and legacy networks are first collected and then the comparison is done. We found that SDN-IP performs better in terms of bandwidth and latency as compared to legacy routing. The experimental analysis of interoperability between SDN and legacy networks shows that SDN implementation in production level carrier-grade ISP network is viable and progressive.

Dysprosium Oxide-Supported CaO for Thermochemical Energy Storage

A novel CaO-based material supported with Ca3Al2O6 and Dy2O3 was found to show excellent performance as a thermochemical energy storage material for use in solar thermal power plants. It retains a carbonation conversion capacity of 82.7% for a period of 40 cycles, as well as exothermic heats of reaction of 582.2 kJ kg−1, up to seven times greater than other materials found in the literature. The improved performance was attributed to the greater prevention of sintering and retention of high surface area by the addition of two inert supports: Ca3Al2O6 and Dy2O3. Long-term effectiveness of the novel material was also evaluated by using a sintering model. It retains an energy storage utilization of 6.2 kg kWh−1 after 30 years of cycling, while commercial limestone would require 81 tons kWh−1 equivalent. Limestone requires replacement every six thermal cycles, making it impractical for real thermochemical energy storage implementation. The extra cost associated with the addition of supports in this CaO-based material is justified by the long-term durability, which would imply a reduction in the overall capital and operational expenditure of the plant.