Paper Mill Wastewater Treatment targets and selection criteria

Frbiz Site


1 effluent water quality, quantity and emission standards


1.1 Wastewater Quality Owners of water according to data analyzed by the water quality, waste water quality indicators shown in the table below:



drywall power sander



disc sanders


Above data is subject to owner approval before they can adopt as the design information.


1.2 Water treatment According to information provided by the owners, the design of the project size








Average daily flow: 8000m3 / d. 1.3 standard According to the requirements of owners, the treated effluent should meet the following criteria in order to meet the recycling and disposal requirements:








" Sewage Comprehensive Discharge Standard "(GB8978-1996) in a standard (new project):


Note: pulp and reuse water quality requires owners.


2. Selection Process 2.1 Principles of Selection Process


Selection process scheme for the construction of wastewater treatment facilities to ensure that the treatment effect of treatment facilities and reduce operating costs play a most important role, it requires a combination of design size, water quality characteristics and the actual local conditions and requirements, select technology feasible and economically reasonable treatment technology, with comprehensive technical and economic analysis to optimize the best overall technical project and implementation modalities.








In wastewater treatment facilities to determine the overall process plan, the following principles:


(1) the selection process must be advanced technology, mature and strong ability to adapt to changes in water quality, stable operation can achieve the factory to ensure water quality standard and the national wastewater discharge standards.








(2) the selection process should reduce capital investment and operating costs, save floor space and reduce energy consumption.








(3) the selection process should be easy to operate, flexible and easy to manage. According to water quality and quantity, should be able to operate on the operation parameters and appropriate adjustments.








(4) the selection process should be easy to achieve automatic control, enhance operational management level.


(5) the selection process should minimize the surrounding Environment Adverse effects (odor, noise, aerosol, etc.).


2.2; the wastewater characteristics of


Wastewater main pollutants COD, BOD, SS, and COD, BOD, SS fiber in the production process is mainly caused by the decomposition, it can also be caused by the SS, paper pulp and paper technology more prominent. Suspended solids in wastewater are mainly long fiber, short fiber, Filler And a small amount of miscellaneous cells. According to the characteristics of waste paper pulp and paper wastewater, and effluent discharge standards, factory waste water treatment programs identified as microfiltration - physical and chemical pretreatment - biochemical method.








2.3 Scheme Selection Process Learn from previous experience in waste water treatment waste paper, pulp and water quality system is part of the production do not ask, as long as the control of COD less than 1500mg / l, SS less than 200mg / l (owners). Can be reused, taking into account the reduction of the scale of investment and reduce processing costs, the program determined by the pore water wastewater effluent screen and flotation of 8000 cubic meters / day, of which 3,000 cubic meters / day used in pulping systems directly back to (Water can meet the technical requirements), and the remaining 5000 cubic meters / hour through biological treatment, the part of the back to use paper-making system, and the surplus part of the discharge standards, then the whole plant wastewater back water up to 75% (6000 cubic m / day), this indicator is leading in the country. (National Environmental protection White Water Reuse Authority requires only 70% efficiency).








Mainly physico-chemical treatment process, combined with biological treatment methods for waste water and reuse water quality requirements, grading of the waste water treatment. Use of micro hydraulic screen filter wastewater recycling paper fiber can be used. By a flotation device to remove suspended solids, some water (3000m 3 / D) that is used back in the pulping process, the remaining waste water (5000m 3 / D) delivered by gravity biological contact oxidation pond, oxidation pond aeration system and the combination of set packing, use of filler on the microbial degradation of organic matter in waste water, ammonia, color, etc., of biological contact oxidation pond effluent gravity into two second flotation device, flotation waste water in the front channel mixer settings, and chemical mixing, reaction tanks were floating in the flotation separation, the water collected by gravity into the clear pond outlet pipe, water up to the national water quality guarantees discharge standards and requirements and paper paper production water standards. A secondary flotation floatation and sludge into the sludge storage tank. Periodic sludge storage tank into the sludge dewatering sludge dewatering devices, sludge disposal Sinotrans. Effluent discharged into the clear water tank for reuse, excess fresh water discharge. (Wastewater reuse technology and equipment are not within the scope of the design)








3 cell design process 1, grille Well Grid layout of a machine, type: LXG-800-2500


Motor power: 1.5kw grid gap: 5mm


Whole stainless steel material. 2, set pool Effective volume 300 cubic meters. Reinforced concrete underground pool, a roof.








3, waste water collecting tank upgrade Pump


Use two sets to upgrade wastewater pump, Model: ISG200-200 (I)


Flow: 400m 3 / H Head: 12.5m motor power: 22kw


A preparation with a Supporting lead bucket 2 4, micro hydro grid








Use micro hydro grid, grid space requirements under the recycled fiber, use gap is 2mm.