Presentation on theme: "Water Treatment. WATER TREATMENT INTRODUCTION Water is vital for life. not only do we need water to drink and to wash but it is also important for many."— Presentation transcript:
WATER TREATMENT INTRODUCTION Water is vital for life. not only do we need water to drink and to wash but it is also important for many of the pleasant recreational aspects of life. The Chemical composition of water as found in different parts of the environment is determine by using analytical techniques. This contains techniques which are usually intended to provide a treatment relating to the overall effect of groups of compounds or ion rather than treating concentration of individual components. Treatments that we shall be looking at including demand (oxidisable material), total organic carbon and electrical conductivity.
LIST OF USES WHICH WE MAKE OF WATER This should include the following, but you may have though of some extra ones of your own:- domestic water supply industrial water supply effluence disposal fishingirrigation power production recreation e.g swimming.
WATER TREATMENT MECHANISM Pretreatment – Equalization, Neutralization, Grease and Oil Removal, Toxic Substances Primary treatment :- Screens, Grit Chambers, Gravity Sedimentation, Chemical Precipitation. Secondary treatment:- Design of Biological treatment system. Physical:- Chemical treatment – Adsorption, ion exchange, stripping, chemical oxidation.
PROCESS SELECTION The selection and proposed in this training is based around the way in which choices are made in reality. The steps involved in this process can be summarized as:- ADetermine sources of waterborne pollution (i)identity areas at risk from this pollution (ii)quantify this risk with immediate action required for those areas suffering damage and long-term action proposed fro areas under potential risk. Characterize water composition and flow variations. Consider existing water availability and likely future demand. BEvaluate the objectives of any proposed water treatment scheme. CConsider any constraints likely to affect development of any proposed strategy. DDetermine the potential revenue available to fund maintenance requirements. ERecommend the most appropriate technology based on the findings of A-D above.
THE IMPORTANCE OF APPROPRIATE STANDARDS Water treatment process and the environmental protection or improvements which it is hoped will result from installation of this process. If the standards are appropriate, realistic and suitably enforced, then the objective of achieved and selection of the most appropriate technology will have been encouraged.
HOW TO ACHIEVE APPROPRIATE STANDARDS Operators of treatment plants are required to obey the law and work within it. Identification of toxic component and impurities parent in water content. Determines the technological level of the process options from which selection is made. Master plant of water treatment unit.
TRACTORS TO CONSIDER IN PROCESS SELECTION FOR WATER TREATMENT. Economy – structure, output by group, industrial component, employment, foreign exchange earnings (exports.) Institutional capacity – Existing roles and responsibilities for organization and management, relationship between departments, level of staffing. Legislation :- policing and regulation responsibilities and capabilities Polities :- bribery and corruption Technological factors :- Education levels, skills, structure of workforce, training Availability of materials / Spare parts:- availability of local knowledge and expertise. Water characteristics:- Composition, flow variations, Sources:- industrial component Present Water supply and sanitation Facilities :- proposed future investments. Environmental factors :- climate, land availability and use patterns, geology, soil conditions, Hydrology (rainfall, river flows). Ground water characteristics Water use for domestic, industrial, agricultural (irrigation) Purpose: future tends. Water resources: availability, reliability quantity, quality, future prospects. Special factors e.g presence of sensitive areas. Social Factors:- Health characteristics, important faecal – related diseases.
RELEVANCE Reliance on sectors of the economy: may limit or favour treatment options Ability and willingness to favour certain treatment options, requirements for staffing, training etc. - fundamental effect on all processes. Ability to cope with water treatment technologies. Many preclude or favour certain treatment options, nutrient imbalance, percentage of impurities, toxicity problems must be addressed. Precludes or farours certain treatment options. water demand and management, waste water re-use and recyding possibilities may need special protection, related in water treatment standards.
FAILURE OF WATER TREATMENT STRATEGIES The in adequate performance of many water treatment facilities in development countries is well documented. There are a large number of reason for this performance and they include:- Failure to consider local conditions and skills A lack of knowledge and experience about the performance of conventional water treatment processes in hot climates Uncharacterised flow and load regimes that generally show much greater variations than those in developed countries. Inadequate data to permit future flow and load changed over the design life of the facility. The direct import of in appropriate technologies without suitable modifications. Problems of maintenance stem from a lack of physical resources, such as spare parts, electricity, chemicals, laboratory facilities and maintenance equipment together with inadequate human resources, in particular skilled personnel and adequately experienced, trained and motivated staff. Inappropriate standards Lack of legislation and institutional problems all contribute to plant failure even where treatment systems have been well designed and constructed.
THE PROBLEMS ASSOCIATED WITH WATER TREATMENT SHEME. Inappropriate process selection and design Lack of resources, both instructional and financial. An inadequate frame work for process monitoring and enforcement of regulations Lack of incentive to keep the plant operating well.
CONCLUSIONS Much literatures is available on the reasons for water treatment strategies. This training is focus on the reasons for such treatment. Some water treatment plant fails this can be attributed to inappropriate decisions having been taken at the process selection stage. This in turn is due to a failure to adequately consider all the basic factors that govern the suitability and sustainability of a water treatment strategy. It has also been proposed that there is an under appreciated need for simple selection aids to ensure that the basic aspects arte considered by those charged with making the decisions. The objectives for a sustainable water management strategy will not be met without appropriate, realistic, suitably flexible and enforceable water treatment standard. This point is drawn out within the body of this paper and it is stressed that the role of standards must be made clear to authorities involved in planning, construction and regulating water treatment strategies.