A Kind Of Innovatory Integrated Equipment For Treating Gas-field Wastewater And The Full Scale Experiment

The gas-field wastewater is the stratum water along with the production ofnatural gas. The concentration of gas-field wastewater changes greatly and it containsmany frothy substances which threaten the environment and human health,so it ishard to be disposed by the ordinary process. A kind of innovatory integrated equipment for treating gas-field wastewater hasbeen manufactured according to its water quality. The treatment of gas-fieldwastewater by the combined system of Coagulation-Air Floatation-Coarse Filter-HAMBBR ( Hydrolytic Acidification Moving-Bed Biofilm Reactor ) - MBBR(Moving-Bed Biofilm Reactor)- BAF(BiologicalAerated Filter)is studied in thisthesis. The integrated equipment has lots of specialties, such as its advanced technics,the high removal efficiency and convenient operation, management, installation andtransportation. So it is very applicable to the treatment of local gas-field wastewater. During the local experiment for over two months, the ranges of COD and BODin the influent are 2300～51050mg/L and 1290～7379mg/L. The removals of CODand BOD of the combined system at an overall HRT of 34.5h achieve 96.68% and99.77%. The effluent COD and BOD range 49~372mg/L and 1.6~12.8mg/L.Moreover, the removals of ammonia-nitrogen, sulfid and SS(Suspended Solid)achieve 95%, 996% and 84.97%, respectively. The experiment shows that thecombined system has great removals of most pollutants in gas-field wastewater. Atpresent there are not similar equipments which can achieve such high effects forgas-field wastewater. The main factors of effect on performance of combined system about the removalof organic substances are investigated, such as temperature, strength of influent,OLRs and pH. Moreover,it is also proved that there are lots of organic substanceshard to be degraded in gas-field wastewater and frothy substances, which aremonitored by means of GC/MS. However, the effluent of combined system canachieve oil industry wastewater let standard No.2. The technical economic analysis of combined system indicates that the treatmentcost is only 5.52yuan/ m3. Compared with the additional methods such as singlechemic treatment, physical treatment and membrane technology, the treatment cost ofthe integrated equipment is low and it holds outstanding market foreground.