What is the industrial wastewater treatment?


Industrial waste refers to waste water produced in the process of industrial production, sewage and liquid waste, containing over water wastage of materials, intermediate products, and products of industrial production and the production of pollutants generated in the process. With the rapid development of the industry, the types and quantities of waste water increased rapidly to water pollution are becoming increasingly widespread and serious threat to human health and safety.


1. the industrial property classification of main pollutants contained in the waste water for wastewater containing mainly inorganic pollutants inorganic and organic wastewater containing orgainic pollutant-oriented, such as electroplating wastewater by inorganic and mineral processing waste water effluent. Food or oil processing waste is organic waste.


2. industrial products and processes can be divided into wastewater, tanning, textile wastewater wastewater wastewater wastewater wastewater, pesticides, metallurgy, oil refining, and so on.


3. the main components of the pollutants contained in the waste water can be divided into: acid alkaline wastewater, wastewater, wastewater containing phenol, chromium-containing wastewater, wastewater containing organic phosphorus and radioactive waste, and so on.


There are also industrial wastewater treatment based on the degree of difficulty and harmfulness of waste, the main pollutants in waste water are divided into three categories:


First class for waste heat from cooling water cooling water can be used again.The processes often use immersion heat exchangers, wide channel heat Exchanger which are corrosion-resistant, easy to clean, such as heat exchangers to recover heat. SEHENSTAR heat recovery heat pump units can also be used to recover the heat heats up, hot water for the other process.


Second for conventional pollutants, there is no significant toxicity and biodegradability of materials, including bio-degradable organic substances can be used as bio-nutrient compounds, and suspended solids;


Category III as a toxic pollutant, that is not easily biodegradable and toxic substances, including heavy metals, toxic compounds and not easily biodegradable organic compounds.


In fact, an industry could be discharged in several different types of waste water, and water will be polluted by contaminants that are different and different effects. Such as dye factories discharged acid wastewater and wastewater discharged alkaline. Textile printing and dyeing waste water, due to the different fabrics and dyes, one of the pollutants and pollution effects will vary greatly. Even a wastewater plant, it probably contains some contaminants. Refinery distillation, catalytic cracking, coking, composite device Tower oil vapor condensation water, containing phenols, oils, sulphur compounds. In different industrial enterprises, although very different products, raw materials and processing may also discharge wastewater of a similar nature. Such as oil refineries, chemical plants, and coking coal gas plant, and may have oil, phenol-containing waste water discharges.




Industrial wastewater treatment · basic flow


Selection of wastewater treatment process is directly related to the amount of construction costs and operating costs, treatment effect, the size of the footprint, ease of management, such as whether or not the key issue. Therefore, the wastewater treatment plant design, must be prepared to process in order to determine the best option.


Determination of level 1, industrial wastewater treatment


When you select wastewater treatment process should first be determined by the nature of the receiving waters water quality requirements, which determine the level of processing, drain national emission standards to be met (GB8978-1996). Set city city and focus basin and the water resources reserves of formed town must construction II level wastewater processing facilities; by NA water for closed or half closed water Shi, for control rich nutrition of, city wastewater should for II level strengthened processing, enhanced except p de nitrogen of effect; non-focus basin and non-water reserves of formed town, according to local of economic conditions and water pollution control requirements, can first level strengthened processing, staging achieved II level processing.


2, industrial waste water treatment process selection factors that should be considered


2.1 technology--scale water quality characteristics, taking into account load of organic matter, nitrogen and phosphorus content; water quality requirements, taking into account requirements and reuse requirements for nitrogen and phosphorus; the removal rate of pollutants, climate and other natural conditions, should consider stability at low temperature in northern China run; the sludge characteristics and uses.


2.2 economic factors--to permit covers an area of, the price of land expropriation; infrastructure; operating costs; level of automation, operational ease, local management capacity.


3, the principle of selection of wastewater treatment process: to ensure that effluent quality should meet the requirements; dealing with stable, mature and reliable technology, advanced applicable; to reduce investment and operating costs, saving power consumption; reduced footprint; convenience of operation and management, operational flexibility and needed to stabilize the sludge; adapted to specific local conditions; actively yet prudently selected wastewater treatment technologies.


4, industrial wastewater treatment process comparison and selection of methods


4.1 technical comparison-programme in Democratic primaries can be compared using qualitative techniques, wastewater treatment process should be dealt with in accordance with the scale of the city, water quality, emissions and water quality requirements, environmental functions of the receiving waters, and local land use, climate, economic realities and requirements on a comprehensive technical comparison and optimizing determined after initial economic comparison.


Options to consider when comparing the main technical and economic indicators include: dealing with investment, reductions of pollutants per unit of water per unit of water consumption and investment, processing costs, power consumption and cost reductions of pollutants, floor space, performance and reliability in operation, management and maintenance ease, the overall environmental benefits, and so on. Can be compared with findings conclusions and lessons learned, and so on, without the need for detailed calculations.


4.2 cost comparison – selected when the final process, 2~3 process you should choose a full range of quantitative economic comparison. Annual cost method or net present value method can be used for comparison.


Annual cost: infrastructural investment programmes and annual operating costs are based on standard rates of return on investment, taking into account compound interest factors, converted into useful cost-matching payments at the end of each year annual costs, compare annual costs for the lowest economic preferred options.


The net present value method: the project uses the entire length of the benefits and costs (including investment and operating costs) in accordance with suitable discounting for present value of base year, balance of benefits and costs the present value of the net present value, net present value of the plan better.


Method of multi-objective decision making: the concept of multi-objective decision making based on fuzzy decision-making, using a combination of qualitative and quantitative systematic review methods. Characteristics identifying evaluation indicators by type of construction, typically by using a 5-point score, benefit the best 5 minute, 1 minute with the worst. Meanwhile, according to the importance of evaluation index for differential treatment (weighted), classified as extremely important, very important, important, and should be taken into account, meaningless five-level. Take little weights to level 1, sorted by 2n-1 upgrade, then press weights to calculate scores, the highest score for multi-objective system optimal solution. Weight should be in accordance with the project specific evaluation projects and properly identified.


Process selection, you can according to the scale of waste-water treatment plant construction, water quality characteristics and emission the degree of treatment required, exclude the application of treatment process, two or three kinds of primary process and then for primary treatment process for a comprehensive technical and economic comparison of the final process.