A Statistical Model for the Geotechnical Parameters of Cement-Stabilised Hightown's Soft Soil: A Case Study of Liverpool, UK

This study investigates the effect of two important parameters (length of curing period and percentage of the added binder) on the strength of soil treated with OPC. An intermediate plasticity silty clayey soil with medium organic content was used in this study. This soft soil was treated with different percentages of a commercially available cement type 32.5-N. laboratory experiments were carried out on the soil treated with 0, 1.5, 3, 6, 9, and 12% OPC by the dry weight to determine the effect of OPC on the compaction parameters, consistency limits, and the compressive strength .Unconfined compressive strength test (UCS) was carried out on cement treated specimens after exposing them to different curing periods (1, 3, 7, 14, 28, and 90 days). The results of UCS test were used to develop a non-linear multiple regression model to find the relationship between the predicted and the measured maximum compressive strength of treated soil (qu). The results indicated that there were a significant improvement in the index of plasticity (IP) with treating by OPC; IP was decreased from 21 to 14.1 by using 12% of OPC; this percentage was enough to increase the unconfined compressive strength of the treated soil up to 1362kPa after 90 days of curing. With respect to the statistical model of the predicted qu, the results showed that the regression coefficients (R2) was equal to 0.8534 which indicates a good reproducibility for the constructed model

Removal of Nitrogen Compounds from Industrial Wastewater Using Sequencing Batch Reactor: The Effects of React Time

This study was performed to optimise the react time (RT) and study its effects on the removal rates of nitrogen compounds in a sequencing batch reactor (SBR) treating synthetic industrial wastewater. The results showed that increasing the RT from 4 h to 10, 16 and 22 h significantly improved the nitrogen compounds’ removal efficiency, it was increased from 69.5% to 95%, 75.7 to 97% and from 54.2 to 80.1% for NH3-N, NO3-N and NO2-N respectively. The results obtained from this study showed that the RT of 22 h was the optimum for nitrogen compounds removal efficiency

Controlling Water Temperature during the Electrocoagulation Process Using an Innovative Flow Column-Electrocoagulation Reactor

A flow column has been innovatively used in the design of a new electrocoagulation reactor (ECR1) that will reduce the temperature of water being treated; where the flow columns work as a radiator for the water being treated. In order to investigate the performance of ECR1 and compare it to that of traditional reactors; 600 mL water samples with an initial temperature of 350C were pumped continuously through these reactors for 30 min at current density of 1 mA/cm2. The temperature of water being treated was measured at 5 minutes intervals over a 30 minutes period using a thermometer. Additional experiments were commenced to investigate the effects of initial temperature (15-350C), water conductivity (0.15 – 1.2 mS/cm) and current density (0.5 -3 mA/cm2) on the performance of ECR1. The results obtained demonstrated that the ECR1, at a current density of 1 mA/cm2 and continuous flow model, reduced water temperature from 350C to the vicinity of 280C during the first 15 minutes and kept the same level till the end of the treatment time. While, the temperature increased from 28.1 to 29.80C and from 29.8 to 31.90C in the batch and the traditional continuous flow models respectively. In term of initial temperature, ECR1 maintained the temperature of water being treated within the range of 22 to 280C without the need for external cooling system even when the initial temperatures varied over a wide range (15 to 350C). The influent water conductivity was found to be a significant variable that affect the temperature. The desirable value of water conductivity is 0.6 mS/cm. However, it was found that the water temperature increased rapidly with a higher current density

The Success of the Construction Industry's Adoption of the Carbon Assessment Strategy PAS2050

PAS2050 was introduced in order to help combat the extremely high levels of emissions that the construction industry emits, as well as the large volume of natural resources they use, through the life cycle of a project. It was developed to create a consistent method of assessing the life cycle of Greenhouse gases as well as a method to increase understanding of where they arise from within a supply chain. This is essential in today's world as without change, the climate will continue to rise in temperature and contribute negatively to the already dramatic effects of climate change that have already been seen. By implementing PAS2050 the industry aims to allow stakeholders to realise the impacts and encourage movement towards a more sustainable future. This research aims to determine how well the construction industry has adopted the carbon assessment strategy covered by PAS2050 through informed opinions, data and case studies. Using journals and research, alongside a questionnaire which will be distributed to individuals within the industry, an informed decision will be made to determine how well the construction industry has adopted PAS2050. The results found that the industry is having difficulty in adapting to the change at all levels and scopes. The findings of this research show that the industry has only touched the surface and although the larger organisations are leading the charge, enough is not being done by smaller organisations and the supply chain

Estimating solid waste generation by hospitality industry during major festivals: a quantification model based on multiple regression

Mega-religious festivals hosted in the city of Kerbala, Iraq, annually generate huge quantities of Municipal Solid Waste (MSW) which negatively impacts the environment and human health when poorly managed. The hospitality sector, specifically hotels, is one of the major sources of MSW generated during these festivals. Because it is essential to establish a proper waste management system for such festivals, accurate information regarding MSW generation is required. This study therefore investigated the rate of production of MSW from hotels in Kerbala during mega festivals. A field questionnaire survey was conducted with 150 hotels during the Arba’een festival, one of the largest festivals in the world, attended by about 18 million participants, to identify how much MSW is produced and what features of hotels impact on this. Hotel managers responded to questions regarding features of the hotel such as size (Hs), expenditure (Hex), area (Ha) and number of staff (Hst). An on-site audit was also carried out with all participated hotels to estimate the mass of MSW generated from these hotels. The results indicate that MSW produced by hotels varies widely. In general, it was found that each hotel guest produces an estimated 0.89 kg of MSW per day. However, this figure varies according to the hotels’ rating. Average rates of MSW production from two and five star hotels were 0.83 and 1.22 kg per guest per day, respectively. Statistically, it was found that the relationship between MSW production and hotel features can be modelled with an R2 of 0.799, where the influence of hotel feature on MSW production followed the order Hs > Hex > Hst

A novel methodology to predict monthly municipal water demand based on weather variables scenario

This study provides a novel methodology to predict monthly water demand based on several weather variables scenarios by using combined techniques including discrete wavelet transform, principal component analysis, and particle swarm optimisation. To our knowledge, the adopted approach is the first technique to be proposed and applied in the water demand prediction. Compared to traditional methods, the developed methodology is superior in terms of predictive accuracy and runtime. Water consumption coupled with weather variables of the Melbourne City, from 2006 to 2015, were obtained from the South East Water retail company. The results showed that using data pre-processing techniques can significantly improve the quality of data and to select the best model input scenario. Additionally, it was noticed that the particle swarm optimisation algorithm accurately predicts the constants of the suggested model. Furthermore, the results confirmed that the proposed methodology accurately estimated the monthly data of municipal water demand based on a range of statistical criteria

An analyses of the status of landfill classification systems in developing countries: Sub Saharan Africa landfill experiences

Municipal solid waste (MSW) management remains a challenge in developing countries due to increasing waste generation, high costs associated with waste management and the structure of the containment systems implemented. This study analyses the classification of landfilling systems by using documented cases reported mainly in publications in waste management in relation to non-engineered landfilling systems/approved dumpsites in Sub Saharan African (SSA) countries from 2000 to 2018. The work identifies an existing system for the classification of landfill sites and utilises this system to determine the situation of landfill sites in SSA countries. Each article was categorised according to the main landfilling management practice reported: Uncontrolled dumping, semi controlled facility, medium controlled facility, medium/high-engineered facility or high state-of the-art facility. Findings suggested that 80% of the documented cases of landfill sites assessed in SSA countries were classified as level 0 or 1. The structure of the containment and controlled regime were identified by the focus group discussion participants as important predictors of possible strengths, weaknesses, opportunities and threats for the landfill sites considered. The study represents the first identifiable and comprehensive academic evaluation of landfill site classification based on site operations reported in the available peer reviewed literature. The information provides insight on the status of landfill sites in SSA countries with respect to the landfilling management practice and a baseline for alternative corrective measures

Enhancing the fuel properties of beverage wastes as non-edible feedstock for biofuel production

A few industries, such as the beverage industry, have experienced some growth in sales during the COVID-19 pandemic. Globally, beverage companies alone generate over 200 million tonnes of biomass annually, which largely ends up as animal feed or in landfills. With the UK government’s commitment to reduce its carbon footprint by at least 68% in 2030, many companies, especially small and medium enterprises (SMEs), are exploring options to reduce carbon emissions and develop roadmaps to become carbon neutral. It has thus become imperative for beverage companies to find value in or repurpose their waste. This paper unlocks the potential for improving the fuel properties of beverage waste through a blending process and explores the determination of optimal fractions for the blends via characterization. With an initial moisture content of 82 and 58 wt.% brewery spent grain (BSG) and spent coffee grounds (SCG), respectively, the pre-treatment process reduced moisture content by approximately 10–15 wt.%. The study concludes that biomass blending improved the fuel properties of the biomass, providing a competitive comparison with coal for energy applications

The Effects of Different Shaped Baffle Blocks on the Energy Dissipation

Stilling basins can be defined as energy dissipaters constructed of the irrigation systems. This study aims at investigating the performance of the new seven baffle blocks design in terms of reducing the dimensions of stilling basins in irrigation systems. In order to assess the hydraulic efficiency of a new model for baffle block used in stilling basins, a Naval Research Laboratory (NRL) has conducted. The results of this study demonstrate that the performance of the new baffle block, in term of hydraulic jump length reduction and hydraulic energy dissipation, it's better than standard blocks. However, the ratios of the drag resistance attributed to the new baffles block (FB / F2) have been larger than that applied on the normal block. It was found that the new block dissipates the energy by 9.31% more than the concrete block, and decreases the length of the hydraulic jump by 38.6% in comparison with the standard blocks. However, the new block maximizes the drag force ratio by 98.6% in comparison with the standard baffle blocks. The findings indicated that in terms of energy reduction and dissipation in the length of the hydraulic jump, the new block is superior to the other kinds

Long-term performance of novel high-calcium one-part alkali-activated cement developed from thermally activated lime kiln dust

The traditional activation approach for alkali-activated cement AAC has several problems resulting mainly from the hazardous and corrosiveness of the alkaline chemicals, such as (NaOH, Na2SiO3), which in turn impede the utilisation of AAC in the construction fields. In this study, A second generation of alkali activated binder was developed using Metakaolin (MK) and natural pozzolan material (NP) (as a source of alumina-silicate), these materials were activated using high-calcium lime kiln dust as solid activator to transform the alumina-silicate crystalline phases to cementitious hydrated products. This was achieved with the aid of heat treatment of materials at different temperatures. Raw materials and final AAC samples were characterised using analytical methods, such X-Ray powder diffraction (XRD), Thermogravimetric Analysis (TG-DTA), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM). Additionally, long-term compressive strength, chemical and microstructural performance were investigated. The transformation of raw materials from crystalline to amorphous phases happened due to the effect of the heat treatment and the formation of stratlingite products in the final AAC paste, which were evidenced using the mentioned characterisation methods. The findings of the present study proved that the compressive strength of the new binder reached 27 MPa and 51 MPa after 28 and 180 days of curing, respectively, ensuring a progressive as well as a higher degree of alkali-activation and disappearance of unreacted alkaline substances in the final AAC products