CN1962492A

CN1962492A - Process for reclaiming PVC slurry waste water using liquid phase suspension method

Info

Publication number: CN1962492A
Application number: CNA200510117669XA
Authority: CN
Inventors: 王小军
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-11-09
Filing date: 2005-11-09
Publication date: 2007-05-16
Anticipated expiration: 2025-11-09
Also published as: CN100537460C

Abstract

The invention discloses waste water recycling disposing technology of polyvinyl chloride slurry through liquid-phase floating method in the environmental protective technique and water disposing technique domain, which is characterized by the following: combining cyclone concrete sediment, pressurized catalytic biological contact oxidization, oxidization sterilization, rough filter and fine filter; using specific concrete and oxide bactericide of PVC slurry, high-effect cyclone concrete sediment and pressurized catalytic biological contact oxidization tower to study the agent and equipment; removing COD and suspension in the PVC slurry step by step; making the outlet water reaching standard.

Description

A kind of process for reclaiming PVC slurry waste water using liquid phase suspension method

One, technical field

The invention provides a kind of liquid-phase suspension process and produce polyvinyl chloride pulp waste water reclamation treatment technology, belong to environmental technology field and water-treatment technology field.

Two, background technology

Present domestic Polyvinyl Chloride System generally adopts liquid-phase suspension process to produce polyvinyl chloride, discharges a large amount of slurry wastewater in the pulp centrifuged dehydration of stripping, and one ton of polyvinyl chloride of every production produces 5～10 tons of waste water approximately).This waste water characteristic is that temperature (about 60～70 ℃), suspended substance, turbidity and colloidal content are higher.In current state-of-the-art in the world Production of PVC technology, do not relate to the treatment process of this water, still adopt the directly processing mode of discharging.According to the pertinent data introduction, the BOD/COD ratio of polyvinyl chloride pulp waste water is about 0.04, so this wastewater biodegradability is relatively poor, and it is higher to carry out intractability with biochemical process.To be de-salted water produce during by the pulp centrifuged machine dehydration of stripping after polymerization is finished as the solvent of polyvinyl chloride monomer polymerization slurry wastewater, thereby the hardness of its waste water, chlorion and soluble solid content thereof are all lower.Today that there is a serious shortage in the supply in water resources, energy day is becoming tight, should pass through certain treatment process, this part water is recycled again, to improve the repeating utilization factor and the save energy of water, protection and rational utilization of water resources.

Three, summary of the invention

Main purpose of the present invention provides a kind of with the polyvinyl chloride pulp wastewater treatment and reach the treatment process of industrial circulating cooling water moisturizing water quality requirement, and this water is recycled.

Treatment process provided by the invention is: the PVC slurry wastewater at first enters former pond (1), main purpose is regulating pondage and homogeneous, and in this process, Xiang Shuizhong feeds pressurized air, waste water is carried out preaeration, some colloidalmaterials are in compressed-air actuated effect lower section oxidation in the water, and volatile matter partly volatilizees.Add PVC waste water specific complex coagulating agent with the lifting of pre-exposure air water and at the pump intake place with pump then, behind the line mixer thorough mixing, enter high-efficiency cyclone coagulating sedimentation device (2) coagulant precipitation, mainly remove most suspended substances and partial organic substances in the former water.Supernatant liquor enters Buffer Pool (3), with pressurized air fully oxidation in pressurized catalysis biological contact tower (4), enters air flotation slot (5) again and carries out gas-water separation after pump promotes pressurization, removes most of organism and colloidalmaterial.The air flotation slot water outlet adds the laggard water collecting basin of oxidation sterilant (6), promote to add through pump and compress into full-automatic filter (7), water outlet enters full-automatic accurate strainer (8) and filters after the coarse filtration, the above molecule of 2 μ effectively reduces turbidity in the removal water, the accurate filter water outlet enters pond (9), filter back, and water up to standard is back to circulating water system.

Four, specific embodiment

1, raw water quality (biodegradability extreme difference; Report according to the water quality that the user provides)

Project	COD _cr	Calcium ion	Temperature	Suspended substance	Chlorion	Turbidity	PH	Specific conductivity	Basicity
Project	COD _cr	Calcium ion	Temperature	Suspended substance	Chlorion	Turbidity	PH	Specific conductivity	Basicity	Unit	mg/l	mg/l	℃	mg/L	mg/l	NTU	μS/cm ²	mg/l
Data	＜169	＜20	60～70	≤40	＜67	＜110	8.43-9.6	300	61	Unit	mg/l	mg/l	℃	mg/L	mg/l	NTU	μS/cm ²	mg/l

2, handle back water quality

For circulating cooling make-up water, main influence index is COD, turbidity in this raw water quality.

Other index is when guaranteeing that these two indexs are up to standard, and is all up to standard.Think after taking all factors into consideration: effluent index should satisfy

COD _Mn＜10mg/l turbidity＜2NTU

Among the attached GB50335-2002 " reuse of wastewater engineering design standard ", reuse water is used as the controlling index of cooling water:

Sequence number	Project	Standard
Sequence number	Project	Standard	1	PH	6.5-9.0
2	Turbidity (NTU)	5	1	PH	6.5-9.0
2	Turbidity (NTU)	5	3	COD(mg/l)	60
4	CL ^-(mg/l)	250	3	COD(mg/l)	60
4	CL ^-(mg/l)	250	5	Total hardness (in lime carbonate mg/l)	450
6	Total alkalinity (in lime carbonate mg/l)	350	5	Total hardness (in lime carbonate mg/l)	450

3, operating parameter determines

Pilot scale begins the back by the running condition of device under different condition is compared, and determines that finally operating parameter is as follows:

4, testing data

Date	10:00				15:00
	10:00				15:00				Former water		Smart filtrate		Former water		Smart filtrate
	COD _Mn	Turbidity	COD _Mn	Turbidity	COD _Mn	Turbidity	COD _Mn	Turbidity	Former water		Smart filtrate		Former water		Smart filtrate
	COD _Mn	Turbidity	COD _Mn	Turbidity	COD _Mn	Turbidity	COD _Mn	Turbidity	8.27	33.6	26.56	11.5	0.55	30.8	28.02	7.2	0.44
8.28	32.8	31.32	6.24	0.44	30.8	32.31	5.92	0.44	8.27	33.6	26.56	11.5	0.55	30.8	28.02	7.2	0.44
8.28	32.8	31.32	6.24	0.44	30.8	32.31	5.92	0.44	8.29	26.8	31.32	8.24	0.44	30.4	31.32	6.56	0.44
8.30	27.2	30.22	7.36	0.55	25.6	30.22	7.52	0.77	8.29	26.8	31.32	8.24	0.44	30.4	31.32	6.56	0.44
8.30	27.2	30.22	7.36	0.55	25.6	30.22	7.52	0.77	8.31	27.2	29.12	7.68	0.44	27.2	25.82	6.08	0.55
9.1	23.2	22.52	7.04	0.44	24.8	18.68	5.12	0.44	8.31	27.2	29.12	7.68	0.44	27.2	25.82	6.08	0.55
9.1	23.2	22.52	7.04	0.44	24.8	18.68	5.12	0.44	9.2	23.6	27.03	6.72	0.44	27.2	26.59	6.08	0.33
9.3	27.6	22.52	7.28	0.55	26.4	32.42	6.00	0.66	9.2	23.6	27.03	6.72	0.44	27.2	26.59	6.08	0.33
9.3	27.6	22.52	7.28	0.55	26.4	32.42	6.00	0.66	9.4	25.6	28.79	6.4	0.44	24.8	30.55	4.96	0.66
9.5	23.6	22.64	4.96	0.77	24.0	23.08	5.12	0.77	9.4	25.6	28.79	6.4	0.44	24.8	30.55	4.96	0.66
9.5	23.6	22.64	4.96	0.77	24.0	23.08	5.12	0.77	9.6	28.8	31.1	5.76	0.44	26.4	27.91	5.6	0.44
9.7	26.4	23.08	6.16	0.55	22.4	22.53	6.08	0.33	9.6	28.8	31.1	5.76	0.44	26.4	27.91	5.6	0.44
9.7	26.4	23.08	6.16	0.55	22.4	22.53	6.08	0.33	9.8	25.6	23.48	7.52	0.44	20.8	24.72	7.2	0.44
9.12	25.6	20.33	0.72	0.66	24.0	20.44	6.88	0.55	9.8	25.6	23.48	7.52	0.44	20.8	24.72	7.2	0.44
9.12	25.6	20.33	0.72	0.66	24.0	20.44	6.88	0.55	9.13	24.8	19.8	5.44	0.44	26.4	21.43	8.32	0.99
9.14	27.2	20.33	9.92	0.44	25.62	21.54	4.16	0.33	9.13	24.8	19.8	5.44	0.44	26.4	21.43	8.32	0.99
9.14	27.2	20.33	9.92	0.44	25.62	21.54	4.16	0.33	9.15	24.8	21.43	6.56	0.55	23.2	20.88	6.80	0.33

9.16	20.40	23.63	7.68	0.33	18.4	23.08	7.28	0.33
9.16	20.40	23.63	7.68	0.33	18.4	23.08	7.28	0.33	9.17	19.6	15.71	6.72	0.44	22.4	15.59	6.32	0.99
9.18	23.2	11.54	6.80	0.33	27.2	12.75	7.36	0.33	9.17	19.6	15.71	6.72	0.44	22.4	15.59	6.32	0.99
9.18	23.2	11.54	6.80	0.33	27.2	12.75	7.36	0.33	9.19	29.2	21.19	5.04	1.54	28.0	22.97	5.12	0.55
9.20	27.6	27.47	6.00	0.44	28.4	26.37	6.16	0.33	9.19	29.2	21.19	5.04	1.54	28.0	22.97	5.12	0.55
9.20	27.6	27.47	6.00	0.44	28.4	26.37	6.16	0.33	9.21	22.4	23.63	6.4	0.33	24.8	27.47	6.64	0.33
9.22	23.2	25.71	5.6	0.33	22.4	29.65	5.04	0.33	9.21	22.4	23.63	6.4	0.33	24.8	27.47	6.64	0.33
9.22	23.2	25.71	5.6	0.33	22.4	29.65	5.04	0.33	9.23	20.8	26.37	4.64	0.33	24.0	25.93	4.48	0.44
9.24	24.0	25.49	6.08	0.33	20.0	27.14	5.92	0.44	9.23	20.8	26.37	4.64	0.33	24.0	25.93	4.48	0.44
9.24	24.0	25.49	6.08	0.33	20.0	27.14	5.92	0.44	9.25	18.8	21.76	5.68	0.44	12.8	18.68	5.44	0.44

5, data analysis

27 days former water average COD _Mn=25.05mg/l

27 days smart filtrate average COD _Mn=6.32mg/l

27 days equal turbidity=24.48FNU of former level

27 days smart filtrate average turbidity=0.497FNU

From entire test, it is no problem that the processing of PVC centrifuge mother liquor is reached the recirculated water index, and treating processes is more easy to control; If full scale plant adopts automatically and detects, control, it is stable that system's effluent index can keep fully; As long as it is good that pre-treatment is done, secondary filter just can keep long-play, and backwash after-filtration performance recovery is better.In addition, 30 days pH values are detected all greater than 7, mean value is 8.13.

6, conclusion

(1) it is fully feasible adopting this art breading PVC factory effluent to make it to reach the circulating cooling make-up water index.Because the former water of PVC waste water is de-salted water, so it is lower to handle back water ions content, has not only reduced the circulating cooling make-up water amount after the adding circulating water system, and reduced total salinity in the recirculated water, reduced recirculated water running cost relatively.Through the recirculated water dynamic analog test, erosion rate and adhesion speed all reach fine level in the petrochemical industry standard.(experiment makes with medicament with corrosion inhibiting and descaling agent for the recirculated water scene)

(2) this technology producing water ratio is greater than 90%.

(3) processing cost is lower, meets the low-cost high-efficiency principle.

The Figure of description explanation

1, former pond 2, high-efficiency cyclone coagulating sedimentation device 3, Buffer Pool 4, pressurized catalysis biological contactization tower 5, air flotation slot 6, water collecting basin 7, full-automatic filter 8, full-automatic accurate strainer 9, pond, filter back.

Claims

1. a liquid-phase suspension process is produced the slurry wastewater recovery processing technique that PVC produces, it is characterized in that: effectively cyclone coagulation precipitation, pressurized catalysis biological contact oxidation, oxidation disinfection, coarse filtration and secondary filter are combined, substep is removed COD and the suspended substance in the PVC slurry wastewater, makes water outlet reach the requirement of reuse water; Used PVC slurry wastewater coagulant special and be applied to integrated dosing, micro-vortex to react, leave standstill the high-efficiency cyclone coagulating sedimentation settling vessel of monotechnicss such as clarification, tube settling;

Used the pressurization bio-contact oxidation device of technology such as integrating pressurized catalysis oxidation, bubble-free aeration, microbial film catalytic oxidation;

Used the special-purpose oxidizing biocide that PVC waste water is had unique sterilization oxygenizement.

2. produce the slurry wastewater recovery processing technique that PVC produces as right 1 described liquid-phase suspension process, it is characterized in that: reduce suspended substance and COD in the PVC waste water to greatest extent by the dosing coagulation, its COD clearance is greater than 50%, and turbidity removal rate is greater than 80%.

3. produce the slurry wastewater recovery processing technique that PVC produces as right 1 described liquid-phase suspension process, it is characterized in that: the special-purpose oxidizing biocide of used PVC slurry wastewater has oxidation susceptibility preferably to organism in the PVC slurry wastewater, and microorganism in the water outlet of pressurization biological contact oxidation tower is had good killing action.

4. as right 1 described PVC slurry wastewater recovery processing technique, it is characterized in that: the operational path that is adopted is " former water → cyclone coagulation precipitation → pressurized catalysis biological contact oxidation → oxidation disinfection → coarse filtration → secondary filter → reuse ".