Evaluation of white water reuse in the bleaching process for reducing fresh water consumption

2007 ◽  
Vol 55 (6) ◽  
pp. 199-204 ◽  
Author(s):  
A.A. Andrade ◽  
P.M. Glória ◽  
J.V.H. d'Angelo ◽  
D.O. Perissotto ◽  
R.A. Lima
Keyword(s):  
Fresh Water ◽  
Water Consumption ◽  
Water Reuse ◽  
Process Integration ◽  
Industrial Process ◽  
Water Stream ◽  
Paper Machines ◽  
White Water ◽  
Electronic Spreadsheet ◽  
Operational Constraints

The main objective of this work is to study the technical viability of using the effluent generated in paper machines (white water) in the wash presses of the bleaching stage, reducing fresh water consumption. As a case study, the industrial process of Ripasa S.A. Celulose e Papel was evaluated. White water rate is about 700 m3/h and it is not possible to reuse all this volume in the bleaching stage without causing operational problems (fouling in tubes and clogging in the screens). A mass balance of the bleaching unit was developed in an electronic spreadsheet in order to evaluate the possibility of reducing fresh water consumption, using only a fraction of the available white water in the wash presses. To achieve this objective some physical-chemistry properties of the white water stream and of other streams of the process were determined. The maximum concentration of some non-process elements (Si, Ca, Mn and Fe), which could accumulate in the process, were determined in order to establish some parameters to allow process integration of the streams involved, considering operational constraints. The results obtained have shown that it is possible to reduce approximately by 13% the consumption of fresh water and this methodology has been satisfactory.

PROCESS INTEGRATION IN THE BLEACHING SECTION OF A PAPER MILL FOR MINIMIZATION OF FRESH WATER CONSUMPTION AND WASTEWATER GENERATION

2013 ◽  
Vol 12 (12) ◽  
pp. 2435-2442
Author(s):  
Sudheer Kumar Shukla ◽  
Deepak Kumar ◽  
Vivek Kumar ◽  
Mukesh Pandey ◽  
Mukesh Chandra Bansal
Keyword(s):  
Fresh Water ◽  
Water Consumption ◽  
Process Integration ◽  
Paper Mill ◽  
Wastewater Generation

USE AND PROTECTION OF WATER RESOURCES OF AZERBAIJAN

2017 ◽  
Author(s):  
Ramiz Tagirov ◽  
◽  
Maya Zeynalova ◽  
Keyword(s):  
Water Resources ◽  
Water Supply ◽  
Fresh Water ◽  
Water Consumption ◽  
Cultivated Land ◽  
Per Capita ◽  
The Republic ◽  
Active Temperature

The article examines the problem of fresh water, since in terms of water supply from its own resources per capita and per 1 km2, the republic is 8 times behind Georgia, 2 times behind Armenia. Significant water consumption in Azerbaijan is caused by its arid territory with a predominance of active temperature and a lack of precipitation, which leads to intensive irrigation of crops. At the same time, artificial irrigation is used on 70% of the cultivated land.

Crisp and Fuzzy Optimisation Approaches for Water Network Retrofit

2007 ◽  
Vol 2 (3) ◽  
Author(s):  
Seingheng Hul ◽  
Denny K. S. Ng ◽  
Raymond R Tan ◽  
Choon-Lai Chiang ◽  
Dominic C. Y. Foo
Keyword(s):  
Linear Programming ◽  
Water Reuse ◽  
Process Integration ◽  
Paper Mill ◽  
Mixed Integer ◽  
Network Synthesis ◽  
Water Recovery ◽  
Water Network ◽  
Real Process ◽  
Integration Techniques

Material reuse/recycle has gained much attention in recent years for both economic and environmental reasons. Process integration techniques for water network synthesis have evolved rapidly in the past decade. With in-plant water reuse/recycle, fresh water and wastewater flowrates are reduced simultaneously. In this work, linear programming and mixed integer linear programming models that include piping cost and process constraints are developed to retrofit an existing water network in a paper mill that was not originally designed with process integration techniques. Five scenarios are presented, each representing different aspects of decision-making in real process integration projects. The fifth scenario makes use of fuzzy optimisation to achieve a compromise solution that considers the inherent conflict between maximising water recovery and minimising capital cost for retrofit.

Design Optimization of a Solar-Powered Reverse Osmosis Desalination System for Small Communities

2013 ◽  
Author(s):  
Jihun Kim ◽  
Karim Hamza ◽  
Mohamed El Morsi ◽  
Ashraf O. Nassef ◽  
Sayed Metwalli ◽  
...  
Keyword(s):  
Reverse Osmosis ◽  
Fresh Water ◽  
Energy Resource ◽  
Production Capacity ◽  
Water Desalination ◽  
Battery Storage ◽  
Water Stream ◽  
Permeable Membrane ◽  
Small Communities ◽  
Solar Powered

Fresh water availability is essential for the economic development in small communities in remote areas. In desert climate, where naturally occurring fresh water is scarce, seawater or brackish water from wells is often more abundant. Since water desalination approaches are energy intensive, a strong motivation exists for the design of cost-effective desalination systems that utilize the abundant renewable energy resource; solar energy. This paper presents an optimization model of a solar-powered reverse osmosis (RO) desalination system. RO systems rely on pumping salty water at high pressure through semi-permeable membrane modules. Under sufficient pressure, water molecules will flow through the membranes, leaving salt ions behind, and are collected in a fresh water stream. Since RO system are primarily powered via electricity, the system model incorporates photovoltaic (PV) panels, and battery storage for smoothing out fluctuations in the PV power output, as well as allowing system operation for a number of hours after sunset. Design variables include sizing of the PV solar collectors, battery storage capacity, as well as the sizing of the RO system membrane module and power elements. The objective is to minimize the cost of unit volume produced fresh water, subject to constraints on production capacity. A genetic algorithm is used to generate and compare optimal designs for two different locations near the Red Sea and Sinai.

Resource use and environmental impacts from Australian export lamb production: a life cycle assessment

2016 ◽  
Vol 56 (7) ◽  
pp. 1070 ◽  
Author(s):  
S. G. Wiedemann ◽  
M.-J. Yan ◽  
C. M. Murphy
Keyword(s):  
Land Use ◽  
Fresh Water ◽  
Water Use ◽  
Water Consumption ◽  
Energy Demand ◽  
Production Systems ◽  
Arable Land ◽  
Ghg Emissions ◽  
Land Occupation ◽  
Fossil Fuel Energy

This study conducted a life cycle assessment (LCA) investigating energy, land occupation, greenhouse gas (GHG) emissions, fresh water consumption and stress-weighted water use from production of export lamb in the major production regions of New South Wales, Victoria and South Australia. The study used data from regional datasets and case study farms, and applied new methods for assessing water use using detailed farm water balances and water stress weighting. Land occupation was assessed with reference to the proportion of arable and non-arable land and allocation of liveweight (LW) and greasy wool was handled using a protein mass method. Fossil fuel energy demand ranged from 2.5 to 7.0 MJ/kg LW, fresh water consumption from 58.1 to 238.9 L/kg LW, stress-weighted water use from 2.9 to 137.8 L H2O-e/kg LW and crop land occupation from 0.2 to 2.0 m2/kg LW. Fossil fuel energy demand was dominated by on-farm energy demand, and differed between regions and datasets in response to production intensity and the use of purchased inputs such as fertiliser. Regional fresh water consumption was dominated by irrigation water use and losses from farm water supply, with smaller contributions from livestock drinking water. GHG emissions ranged from 6.1 to 7.3 kg CO2-e/kg LW and additional removals or emissions from land use (due to cultivation and fertilisation) and direct land-use change (due to deforestation over previous 20 years) were found to be modest, contributing between –1.6 and 0.3 kg CO2-e/kg LW for different scenarios assessing soil carbon flux. Excluding land use and direct land-use change, enteric CH4 contributed 83–89% of emissions, suggesting that emissions intensity can be reduced by focussing on flock production efficiency. Resource use and emissions were similar for export lamb production in the major production states of Australia, and GHG emissions were similar to other major global lamb producers. The results show impacts from lamb production on competitive resources to be low, as lamb production systems predominantly utilised non-arable land unsuited to alternative food production systems that rely on crop production, and water from regions with low water stress.

Antibiofilm activity of biomolecules: gene expression study of bacterial isolates from brackish and fresh water biofouled membranes

Biologia ◽  
2016 ◽  
Vol 71 (3) ◽  
Author(s):  
Smita Pal ◽  
Asifa Qureshi ◽  
Hemant J. Purohit
Keyword(s):  
Salicylic Acid ◽  
Fresh Water ◽  
Industrial Process ◽  
Life Time ◽  
Antibiofilm Activity ◽  
Expression Study ◽  
Chemical Cleaning ◽  
Natural Agents ◽  
Membrane Biofouling ◽  
Exopolysaccharides Production

AbstractMembrane biofouling is a common and emerging problem, where cells get cemented and create problems in industrial process. Frequent chemical cleaning used for the treatment of biofouled membrane shortens the membrane life time and creates ‘stress’ to existing microflora to trigger more exopolysaccharides production, which becomes the principle cause of biofouling. To understand safe and environmentally feasible antifouling strategies, key biofilm forming representative bacteria isolated from brackish and fresh water biofouled membranes were subjected to natural agents, such as vanillin (0.05–0.4 mg/mL) and salicylic acid (0.1–0.7 mg/mL). Salicylic acid (0.7 mg/mL) was found to be effective against only

Study of dissolved silicon, and nitrate dynamics in a fresh water stream

2001 ◽  
Vol 35 (11) ◽  
pp. 2749-2757 ◽  
Author(s):  
W.A House ◽  
D.V Leach ◽  
P.D Armitage
Keyword(s):  
Fresh Water ◽  
Water Stream ◽  
Dissolved Silicon

A NEW WATER-BUG FROM CANADA

1897 ◽  
Vol 29 (3) ◽  
pp. 56-56
Author(s):  
William H. Ashmead
Keyword(s):  
New Species ◽  
Fresh Water ◽  
North American ◽  
South American ◽  
The South ◽  
Water Stream ◽  
The North ◽  
Water Species

The interesting new species of water-bug described below was received some time ago from Abbé P. A. Bégin, of Sherbrooke, Canada. It was captured swimming on a fresh-water stream some little distance above Sherbrooke, and is of more than ordinary interest, from the fact that it belongs to the genus Halobatopsis, Bianchi, a genus not yet recognized in the North American fauna, and only recently characterized, being based upon the South American Halobates platensis, Berg., also a fresh-water species.

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