Environmental Engineering

“The CIH Exam - Essential Practice Questions by Farcas, Hammond, and Cena is, as the name implies, an essential set of questions in Industrial Hygiene. It is well laid out in 17 sections. The questions are well introduced with a short narrative before the introduction of the pertinent equations and solution to the over 500 example problems. The book serves not only as a formidable preparation for the CIH exam but a good review of basic principles, a reference for many of the day-to-day technical issues confronting the practicing industrial hygienist, and a guide for raising awareness of potential problems for which alert action is required. The authors bring a breadth of experience and insight into the issues handled in the text. They bring context to the basic principles to be highlighted by the examples of the questions and their solutions. This should be a must-have text for everyone in the field.”Michael McCawley, Ph.D.

The current status of solid waste management in Lahore, a metropolitan city of Pakistan, is reviewed in this article using an existing approach, the UN-Habitat city profile. This involves a systematic quantitative and qualitative assessment of physical components and governance features of the current waste management system. A material flow diagram (MFD) is developed, which allows visualisation of the current waste management system with all related inputs and outputs. This study shows that in the current system, waste collection and transportation is the main focus, however the collection coverage is only about 68%. There is no controlled or even semi-controlled waste disposal facility in Lahore. There is no official recycling system in the city. It is estimated that currently ~27% of waste by weight is being recycled through the informal sector. Making use of the organic content of the waste, a composting facility is operative in the city, producing 47,230 tonnes year(-1) of orga...

Excel spreadsheet Settling Velocity.xls (2.1) calculates the terminal settling velocity of single spherical particles and of single natural sediment particles, in liquids and gases. It also predicts the hindered settling velocity of concentrated suspensions, by using Richardson & Zaki’s Law.
Guo (2002), Song Zhiyao et al. (2008), and Cheng (2009) combined the 3 “classical” settling velocity equations on laminar flow (Stokes’ Law), intermediate flow, and turbulent flow (Newton’s Law) each to only one relatively simple “new” settling velocity equation, used in this spreadsheet.
Calculations by these new settling laws are compared and contrasted with the sometimes tedious
classical calculations, and validated by graphical and manual sedimentation calculations.
13 worked examples illustrate how to use this spreadsheet, and how do manual calculations.

Natural cementation affects the properties of soils, the interpretation of in situ and laboratory test results, and the selection of criteria for geotechnical design. In this paper, published experimental studies are reviewed, a microscale analysis is presented of the effect of cementation on small-strain stiffness for distinct stress-cementation histories, and the effect of cementation on small-strain velocity and damping is experimentally studied. Observations include the prevailing effects of cementation over effective stress, the coexistence of frictional and viscous losses, and the effects of decementation when the medium is unloaded from the level of confinement prevailing during cementation.Key words: wave velocity, seismic response, stiffness, damping, sampling effects, loading history.

Exposure to nitrogen dioxide (NO2) poses a danger to the health of many children all over the world especially children that attend schools in the vicinities of traffic roads and industries. This research study aims to assess the impacts of NO2 exposure on the health of the students. NO2 samples were collected by tube-type passive samplers. Moreover, the investigation of indoor NO2 exposure of students was associated with physical human health by using multiple logistic regressions. The results revealed that the indoor and outdoor NO2 concentrations in elementary schools were 9.0 ± 4.4 to 16.7 ± 2.7 μg/m3 and 8.2 ± 2.1 to 17.7 ± 6.7 μg/m3, respectively. However, indoor and outdoor values of NO2 were lower than the WHO standard of 40 μg/m3. Non-carcinogenic risk assessments of NO2 were carried out to help assess the health risks of students. It was found that the HQ of all those who studied in schools was less than 1, indicating no health risks. However, NO2 in classrooms can cause e...

ABSTRACT:A biofuel is a fuel that is produced
through contemporary processes from biomass,
rather than a fuel produced by the very slow
geological processes involved in the formation
of fossil fuels, such as oil.
Since biomass technically can be used as a fuel
directly, some people use the terms biomass and
biofuel interchangeably. More often than not,
however, the word biomass simply denotes the
biological raw material the fuel is made of. The
word biofuel is usually reserved for liquid or
gaseous fuels, used for transportation.Biofuels can
be classified into two categories: primary and
secondary biofuels. The primary biofuels are
directly produced from burning woody or cellulosic
plant material and dry animal waste. The secondary
biofuels can be classified into three generations that
are each indirectly generated from plant and animal
material. The incessant increase in world
population growth leading to increased human
activities in the form of transportation,
industrialization and other economic activities
results into high energy demand to satisfy the
human socio-economic development. Fossil fuel
(Coal, Oil and Gas) based energy generation has
been in usefor years which brings about carbon
dioxide emission, causing health issues for man
and the environment. This study evaluates the
impacts of fossil fuels and readily available
opportunities in biofuel as an alternative source of
energy for sustainable economic development. The
continuous consumption of fossil fuel as a major
source of energy has
contributed adversely to the emission of Green
House Gases (GHG) and eventually lead to Climate
change. Biomass can be obtained from the
following resources wood and agricultural
products, landfill and biogas, livestock residues,
ethanol/biodiesel and solid waste. Biofuel produced
from biomass which can replenish itself quickly
after consumption is called Renewable energy. This
study focuses on biomass and their various
sources.In this research we describe the economic
benefit of biofuel for cleaner environment and
economic development. Recommendations was
made on how to improve on current biofuel
production for sustainable energy.
Keywords: Biomass, Bioethanol, Biofuel,
Renewable energy, Transportation

There has been considerable interest focused on the investment for the production of oilseed crops for biodiesel. The advance research is needed to provide knowledge needed for the feasible way of adaptation of oilseed crops for biodiesel. Among the various oilseed crops produced, sunflower is a prominent summer crop that can be used to produce on-farm biodiesel for energy security. The objective of this paper is to estimate the overall economic benefits of biodiesel production from sunflower under small scale settings. The economic viability on production of biodiesel and its market opportunity to the farmers were investigated at its 3 different production stages namely; seed, oil and seed meal, and biodiesel production. The study was based on three different on-farm biodiesel extraction scenarios. For example, the seed press and biodiesel extractor can be operated at three different rates (low, medium and high). Feedstock production, capital investment for biodiesel units and operations costs were considered for the analysis. To calculate cost and revenue in annual equivalent terms, the present values of all costs and revenues over the useful life was transformed into an equivalent annuity. Analysis shows that biodiesel production from sunflower production could generate positive net returns under various scenarios. The analysis per volume basis showed that the production cost of biodiesel from sunflower oil to producer was between $2.00 to $3.21/gal when revenue from seed meal was accounted. The estimated break-even price of sunflower seed range from $0.18 to 0.26/kg depending upon sunflower yield. The findings of this research further improve the understanding of growing sunflower as an oilseed crops and on-farm processing of oil for local biodiesel production that could play vital role in improving farm income as well as sustainable and independent energy for small farmers.

The looming energy crisis due to both prevailing and prospective exhaustion of non- renewable energy resources such as coal, oil and gas has gripped the whole world. As a result, renewable sources of energy such as wind, solar, Hydrogen, biomass, etc are being harnessed and developed for their utilization as the alternate energy sources to cover for the depleting energy sources. This research review paper is based on the comparison of studies that involve the designing and fabrication of microbial fuel cell (MFC) as a means of producing sustainable production of electric power. The main aspects of MFC research are to reduce the cost of treatment as well as simplifying operational or functional conditions. MFCs can be the next generation of fuel cell technology and thus might play an important role in energy conservation, electricity generation, bio-hydrogen production, biosensors and wastewater treatment as well as in alternate fuel utilization using microorganisms to generate elect...

Inoculum is a crucial factor influencing the success of an anaerobic digester start-up. This study evaluated the efficacy of aerobic waste activated sludge (WAS) to start-up anaerobic hybrid reactors (AHR) treating cassava wastewater. The start-up performance and stability of five 6.2 L AHRs inoculated differently by WAS (AHR1) and WAS co-inoculated with pig manure (AHR2), cow dung (AHR3), chicken manure (AHR4), and anaerobic pond sludge (AHR5) were investigated. The results depicted the potential of WAS as starter seed for AHR's start-up. This sludge contained methanogenic populations, mainly Methanomicrobials, Methanosarcinales, and Thermoplasmatales, for 1.5 × 107 MPN/g VS compared to 4.0 × 103-6.0 × 107 MPN/g VS in manures and anaerobic sludge. Co-inoculation of WAS with cow dung (AHR3) and anaerobic sludge (AHR5) promoted a rapid start-up, achieved 4.0 kg COD/m3.d within 1.5-1.7 months, while about 2.5-3.3 months needed for the others. A satisfying performance, stability, m...

The temporal evolution of nine daily precipitation indices over the northeastern Iberian Peninsula was analysed for the period 1955–2006, using data from 217 observatories. Cross-tabulation analysis enabled detection of statistically significant overlap among spatial distributions of trends in the study area. There was a general decrease in annual precipitation at most observatories, a decrease in the number of rainy days and precipitation intensity and an increase in the duration of dry spells. The frequency and contribution to annual precipitation of moderate and heavy rainfall events did not change at most observatories, or showed a decreasing trend in these events. There was very large spatial and seasonal variability, with implications for water management and risk assessment in the region. The decrease in precipitation was very marked in headwaters during winter and spring, potentially affecting reservoir management in the region. Heavy rainfall events generally decreased in the west of the region in winter, and in the east of the region in autumn, when these areas are more exposed to hazards related to extreme rainfall. Large differences in the sign and magnitude of trends occurred over very short distances, suggesting the need for dense networks of observatories to ensure reliable and robust detection of regional trends. Copyright © 2009 Royal Meteorological Society

All the storms and depressions that formed in the Bay of Bengal during 1974–99 have been analysed. The number of occurrences in July is not in harmony with that of other months of the monsoon. Regions stricken are taken into account on a monthly, seasonal and annual basis. The Indian coast faces almost an equal number of storms and depressions that are formed from June to November. The most vulnerable months for storms are May, October and November for Bangladesh; May for Myanmar; June, August and September for Kolkata–Vishakhapatnam in India and October and November for Vishakhapatnam–Tamilnadu in India. Most of the monsoon depressions cross the Kolkata–Vishakhapatnam coast of India. The frequency of formation has been observed to decrease during the period of analysis. It is also observed that the frequency distribution of the Bay of Bengal storms has two peaks: one in the month of May and the other in the month of November. Copyright © 2003 Royal Meteorological Society

Working with Rutland Regional Planning Commission to meet the below community objectives:

1. Site planning to initiate redevelopment of underutilized property in Downtown Rutland.

2. Increase vibrancy and economic development of area through design focusing on creating a human-scale, walkable, and mixed-use environment.

Listed below are the expected long-term project benefits of this engineering design:

• Increased tax base resulting from commercial and residential growth.

• Reuse of existing infrastructure from urban site will lower municipal costs to provide services.

• Human-scale and walkable building design will attract large demographic groups such as baby-boomers and millennials.

• Building and streetscape design facilitating all modes of travel, especially bicycle and pedestrians will reduce automobile dependence, lowering future health care and environmental costs.

• Residential development in the downtown core will increase vibrancy and foster economic development.

• Development in the downtown area will reduce development pressure on rural, working lands thus supporting agricultural and forestry enterprises and maintaining the landscape of Vermont, supporting the tourism industry.

• Site redevelopment using green infrastructure stormwater management measures will improve water quality and the natural environment.