Imran Nazir Unar

A Promising Technology of Pressure into Power: A Case Study of Pressure into Power Approach in Gas Transmission Lines in Pakistan

Pakistan is gas rich but power poor country. Conventional approach is always directed toward power plants using fossil fuel. Some trials have also taken place demonstrating wind and other nontraditional energy source for generating electricity. A pragmatic and feasible unexploited resource is the potential energy from high-pressure natural gas. Currently, this energy is being wasted at gas pressure reducing stations in Pakistan. At present there are two integrated gas companies (transmission and distribution), i.e., Sui Southern Gas Company Limited (SNGPL) and Sui Northern Gas Pipelines Limited (SSGCL). The gas is transmitted through the transmission pipelines in the pressure ranges of 800–1,000 psig. The gas is distributed by reducing from the transmission pressure into distribution pressure up to a maximum level of 150 psig at the city gate stations normally called “sales metering station (SMS).” There are almost more than 200 SMSs in SNGPL and SSGCL. This study highlights real possibilities to utilize the energy lost in gas reducing stations (SMSs) as a source of electrical power. The present study shows that with average pressure ratio (ratio of upstream to downstream pressure) of 10 and average gas flow of 35 MMSCFD from any gas metering station, more than 2 MWe power could be generated without consumption of any fuel.

Sustainable Development Indicators for Energy in Pakistan

The strong challenges of sustainable development are as diversified and complex as the human societies and natural ecosystems around the world. Sustainable development requires the participation of diverse stack holders, with the idea of reconciling different and sometimes opposing values and goals toward a coordination of mutual action to achieve required goals. Energy sector issues and developments continued to severely constrain Pakistan’s economy in 2009–2010. Against a backdrop of a sharp increase in the international price of oil through the calendar year 2009, which put enormous upward pressure on the cost structure in the power generation (and transport) sector, in particular, large domestic supply shortages of electricity and gas occurred. Lower accumulation of water reserves in dams compounded the severity. The cumulative effect of the energy crisis on the economy is estimated at upward of 2% of gross domestic product (GDP) during 2009–2010 alone. Brundtland Commission and others provide the background for the approach we have chosen to structure the indicators. Sustainability indicators are generally designed to illustrate the economic, environmental, and social dimensions of sustainable development. Policymakers need methods for measuring and assessing the current and future effects of energy use on human health, human society, air, soil, and water. Energy indicators for sustainable development: guidelines and methodologies, IAEA (Energy indicators for sustainable development: guidelines and methodologies, Vienna, 2005) are focused here. Some guidelines are recommended for the sustainable development of energy in Pakistan.

Environmental Impact of Untreated Effluents from Sugar Industry: A Case Study

Sugar industry, being the major consumer of water, discharges its effluents into the outside environment mostly as untreated. However, besides knowing about the pollution strength of these effluents, knowledge about the mode of disposal of these effluents into the surroundings is also crucial. Thus, an intensive investigation was carried out to know the disposal patterns adopted by three selected sugar mills, namely, Habib Sugar Mills, Nawabshah, Matiari Sugar Mills, Matiari, and Fauji Sugar Mills, Tando Mohammad Khan, along with the obvious problems people were facing as a result. The study concluded that the disposal of untreated effluents into the surroundings had a negative impact on the resources such as land and water (both surface and ground) in particular and on the health of people and their livestock in general.

Value-Added Product Recovery from Banana Plant Waste: A Sustainable Way for Development

Pakistan being an agriculture country is enriched with abundance of biomass residues from agricultural crops such as wheat straw, rice husk, bagasse, banana plant, etc. that may be used for resources recovery. The banana plant is one of the potential cellulosic material like cotton crop, wood, etc., obtained from agricultural land. Development in the area of bio-conversion offers a cheap and safe method of not only disposal of agricultural residues but may also be used for the production of product, like, ethanol. Ethanol production from cellulosic material is a two stage process. Initially, the cellulosic material is converted to reducing sugar by acid hydrolysis or enzymatic hydrolysis and afterward, production of ethanol by fermentation process. The current work focuses on the optimization of acid hydrolysis and fermentation using Sacchromyces cerevisiae yeast. In the current study, process conditions for acid hydrolysis, i.e., particle size, reaction time, shaking speed, temperature and concentration of acid were studied in addition to fermentation process optimization. In acid hydrolysis, samples of various particle sizes, i.e., 26, 28, 30, 40, 50, and 100 μm, were used. It was found that reduction in particle size enhances the conversion of reducing sugars from banana plant. The optimized conditions for hydrolysis were found to be shaking time 2 h, temperature 80°C, shaking intensity 90 rpm, and solid–liquid ratio 50 g in 300 ml of H2SO4. With 100-μm particle size, optimum yield of Brix (reducing sugar) was obtained (21–24% per 300 ml). pH was adjusted in the range of 4.5–5.2. For the production of ethanol, aerobic fermentation was carried out using S. cerevisiae yeast species. The fermentation reaction was carried out in a 300-ml conical flask. Optimum yield was obtained at 31°C, residence time 8 h, and when shaken at 80 rpm.