CN101233085A

CN101233085A - Biowaste treatment

Info

Publication number: CN101233085A
Application number: CNA2006800281155A
Authority: CN
Inventors: S·李
Original assignee: United Utilities PLC
Current assignee: United Utilities PLC
Priority date: 2005-07-05
Filing date: 2006-07-04
Publication date: 2008-07-30
Also published as: GB0513680D0

Abstract

A method of treating bio waste comprising the steps of (1) fermenting substantially raw biowaste in a pathogen reduction stage under anaerobic conditions for a predetermined period at a temperature in the mesophillic temperature range and (2) subsequently separating the solid and liquid phases to produce a fermented cake and fermented liquor. The fermented cake has at least 15% solids on dry basis and contains over 500 mg/L ammonia, over 1,000 mg/L total Volatile Fatty Acids (tVFA) and Escherichia coli less than 100,000 cfu/g dry solids. The fermented liquor contains over 10,000 mg/L COD, over 500 mg/L ammonia, over 1,000 mg/L tVFA and less than 5,000 mg/L of suspended solids.

Description

Ecological waste treatment

The present invention relates to relevant product and the process of processing with biological waste (for example sewage sludge and animal waste).

Sewage sludge is the material that is precipitated out in the municipal wastewater treating processes, and described municipal wastewater generally comprises the waste water of sanitary sewage and industrial source.

Animal waste generally is to be produced by the animal rearing activity (AFO) on farm or the pasture, and people are the restricted area in described farm or pasture guard and raise these animals.AFO on little land area, trooped animal, feed, muck and urine and activity in production.Feed feed to animal rather than animal in the pasture, former Yezhong or on the grassland, herd.The AFO of common type comprises dairy farm, cattle farm, poultry-farm and pig farm.The pollution relevant with AFO reduces the quality of water, threatens the drinking water source, and may damage air quality.Yet,, can become valuable resource from animal rearing active muck if suitably handled and utilize.

The source of biological waste as fertilizer sources and soil conditioner is widely used in agriculture production.In order to make these refuses be suitable for this purposes, must at first handle them, be not only in order to reduce its pathogenic agent content and in order to make these materials stable by reducing its organic content.The modal method that is used for this processing is the anaeration in normal temperature digestion method, usually is abbreviated as MAD.Traditionally, described MAD method divides two stages to carry out usually,, continues 12 to 24 days initial digestion phase down at 35 ℃ that is, is 14 days storage by a definite date then.Initial digestion is converted into methane with a part of organic content.Storage causes the reduction of pathogenic agent content.The biological waste dehydration that usually will digest is to produce a kind of cake, and purpose is to reduce the cost that stores and transport.

The shortcoming of tradition MAD method comprises this fact, that is, this method is very slow and the less ability of its pathogenic agent is very limited.In the past, the applicant openly crossed the mud insulation processing (UK 0126963.8 11/09/2001) that was used to reduce pathogenic agent before digestion, and this processing provides improved pathogenic agent to reduce ability and eliminated storing the needs in stage.Yet this overall treatment time of improving one's methods is still quite long.In addition, no matter the digestion method that adopts how, all digested sludge all shows the trend of supporting pathogenic agent (for example intestinal bacteria (Escherichia coli)) regrowth and producing foul odour (if they stand the intensive shear field, for example situation that can experience in the dehydration that adopts whizzer).

In addition, the phosphate content in the waste water can cause problem.In Europe, (UWWTD 91/271/EEC) has formulated minimum standard about blowdown to Municipal waste water treatment policy.These rules are applicable to described discharging, no matter be landlocked surface water, underground water, river mouth or or offshore waters.These standards are mainly based on BOD, SS, N and P, and the level that will meet depend on serviced crowd's size and receiving waters be classified as normally, responsive, or not too responsive.Though be useful on the accepted method that removes BOD, SS and N from waste water, it is also not quite satisfactory that present being used to removes the scheme of P.In most of the cases, the operator depends on for this purposes and uses molysite.Use molysite that many important disadvantages are arranged, comprise short supply, remainder fe is to the deleterious effect of aquatic environment, and because the essence that the mud that the use of iron causes generates increases, this will need disposal.The tertiary iron phosphate that is produced by this process is not a bioenergy utilization, does not therefore almost have agronomical value.A kind of better alternative method is biological phosphorus removal method (BNR), and this is a kind of technique known, and this technology is based on the organism activity under anaerobic of accumulating poly phosphoric acid salt (poly-P).The Poly-P accumulation highly depends on the compounded carbons fermentation and is voltaile fatty acid (VFA).Generally speaking, additional dissolved organic matter matter is to produce by the interior carbon source of fermentation from sewage, and described fermentation is not that the anaerobic zone of sewage work is exactly to carry out in the pre-fermentation container of special use.

The generation of VFA can be the result of mud or precipitable solid fermentation in the sewage.Generally speaking, mud can cause significantly improving of VFA concentration, and the result who obtains from former raw sludge is better than from the result of mixing sludge acquisition.The pre-fermentation container of most of physical sizes is charging with former raw sludge.These pre-fermentation containers are called as " the pre-fermentation container of effluent ".Former raw sludge is the concentrated underflow of primary clarifier and is also sometimes referred to as primary sludge.So-called " online pre-fermentation container " is charging with the raw waste water rather than is charging with former raw sludge.An example of online pre-fermentation container is active elementary jar (APT).APT produces VFA by allowing sludge blanket form in primary clarifier.Fermentation and VFA generation take place in this sludge blanket then.Mud is looped back inlet, and this working cycle is considered to the solid inoculated into the active fermentation organism, the VFA that forms in the elutriation sludge blanket.These known VFA generation systems that are used for BNR adopt unconcentrated mud to operate at ambient temperature.The shortcoming of this type systematic comprises volume that it is big and low VFA throughput rate.Under the situation of further processing (for example by digestion or compost), also be not suitable for the agricultural circulation from the sludge part of its acquisition.In addition, always pollute from the VFA in these sources the high-load P that discharges from mud is during the fermentation arranged.To make them be not so effective in BNR uses in the existence of P among the VFA.All of these factors taken together together with the normal weak sewage seen in many European countries (for example UK), means and can not realize gratifying BNR, particularly removes about P.External carbon source realizes unique feasible method of consistent factory's performance often, and described external carbon source can be VFA, but also can be methyl alcohol, ethanol or waste water with high dissolubility COD concentration, for example from food processing plant.

An object of the present invention is to eliminate or alleviate above-mentioned shortcoming.

So, first aspect of the present invention provides a kind of method of handling biological waste, this method comprises the steps: under (1) temperature in mesophilic range, with under anaerobic one section preset time of biological waste fermentation in the pathogenic agent minimizing stage, separate solid phase and liquid phase subsequently to produce fermentation cake and fermented liquid with (2).

Second aspect of the present invention provides the fermentation cake that contains at least 15% solid biological waste source by butt, it contains and surpasses 500 mg/litre ammonia, surpasses 1,000 mg/litre general volatile lipid acid (tVFA) and be lower than 100,000cfu/ restrains dried solid intestinal bacteria.

More preferably, described fermentation cake has by butt 20% solid at least, particularly in the 20%-45% scope.Preferably, described cake contains and surpasses 1000 mg/litre ammonia, 1500 to 3500 mg/litre more preferably.The tVFA content of described cake is at least 3000 mg/litre preferably, are more preferably the 5000-25000 mg/litre, and intestinal bacteria are to be lower than 10, and 000cfu/ restrains dried solid, and the amount more preferably less than 1000 exists.

The 3rd aspect of the present invention provides the fermented liquid in biological waste source, and it contains and surpass 10,000 mg/litre COD, surpasses 500 mg/litre ammonia, surpasses 1,000 mg/litre tVFA and the suspended solids that is lower than 5,000 mg/litre.

Fermented liquid preferably contains at least 20,000 mg/litre COD, preferably in 20,000 to 40,000 scopes.Described fermented liquid preferably contain at least 1500 mg/litre ammonia, it is desirable in 1500-3500 mg/litre scope, and the tVFA content that has is at least 3000 mg/litre, preferably in the scope of 5000-25000 mg/litre.Suspended solids in this liquid is preferably lower than 3000 mg/litre.

Accessiblely be that the fermentation cake of a second aspect of the present invention and the third aspect and fermented liquid are preferably produced by the method for a first aspect of the present invention.

Described pathogenic agent minimizing stage (step (i)) comprises the fermentation of primary biological waste in fact, the described biological waste of primary is not in fact inoculated it to this refuse interpolation and/or with this refuse combined inoculation thing (for example mud of part digestion) in other words.In addition, in the digestion of traditional anaeration in normal temperature, during described refuse remained in the temperature and with the time of sludge seeding above 12 days of part digestion.In contrast, with regard to the present invention, separate the solid part of described fermentation waste and liquid portion immediately to produce fermentation cake and fermented liquid by mechanical means.

Accessible is that term " biological waste " generally is meant the waste stream that is produced by the industrial operation that relates to the biological degradability raw material, and may contain deleterious pathogenic agent.This class refuse comprises, for example sewage sludge, farmyard mud, Slaughterhouse waste and from the refuse of other commercial run.In addition, this term " biological waste " is used in reference to such refuse, and it has higher organic content and does not get rid of pretreated to a certain degree possibility.Therefore, term " biological waste " should broadly be interpreted as being meant the waste stream with high organic content.Usually, this will be that total chemical oxygen demand (COD) (COD) is greater than about 10, the refuse of 000 mg/litre, although the material of being paid close attention to may have 30 in actual applications, 000 to 100, the COD of the scope of 000 mg/litre and the BOD (5 days) (described BOD shows the biological degradability of charging) in the scope of 5,000 to 50,000 mg/litre.The primary waste stream may have 1 to 40% solid and residuum is a water.The general part of described solid is soluble form, and part is suspension form.Preferably, described solids content should be in 3 to 15% scope.The solids content of waste stream can adopt any mode easily to be regulated.For example, can before the described pathogenic agent minimizing stage, during or even use the described waste stream of wastewater dilution afterwards.Have been found that dilution can improve the recovery of general volatile lipid acid.Described waste stream should preferably have seldom or not have the waste stream of remarkable pathogenic agent content.

Described mesophilic range is understood that from about 25 ℃ to about 46 ℃.In the present invention, preferred operating temperature range is between 32 ℃ and 42 ℃.

Have been found that suitable fermentation time is from about 1 day to about 6 days.In the present invention, preferred fermentation time is between 2 days and 5 days.Therefore, shortened suitable fermentation cake and the required time of fermented liquid of making valuable resource of preparation greatly by implementing method of the present invention.

Be suitable for that solid-liquid separating method of the present invention comprises that all known dewaterings are for example centrifugal, belt press and pressure filter.These methods usually need pre-treatment, for example adopt coagulating agent and/or pH regulator, and therefore, method of the present invention can comprise a pre-treatment step.This method produces the liquid that cake that a kind of solids content is 20% to 40% dry weight and a kind of suspended solids content generally are lower than 5,000 mg/litre.

Method of the present invention can intermittent mode operation or operate continuously.Preferably, this method is operated in a continuous manner, adopts placed in-line many reactors, and purpose is to avoid pathogenic agent effluent (bypass).

More preferably, take out the fermentation waste of small part, and air or oxygen is introduced this fermentation waste from reactor.The VFA that exists in this fermentation waste is oxidized to carbonic acid gas, described carbon dioxide generating heat, and heat can be used for heating the less interim biological waste of pathogenic agent, improves the efficient of the inventive method thus.

More preferably, provide placed in-line at least 3 containers, particularly 6, wherein take out the fermentation waste of small part and use it for one or more containers that heat other container from one or more containers.The heat that is produced by described fermentation waste can shift out and loop back in the described container one or more with heat exchanger.Then, the oxidative fermentation refuse that described heat can be moved out of with merge from the refuse of one of described container (last in preferably connecting) and send into pressure filter.

Perhaps, can at regular intervals oxygen or air be added one of described container (preferably first container), to produce heat.

During fermentation process, some bacteria cultures discharge enzymes with macromole for example lipid, protein and carbohydrate breakdown become less molecule, other bacterium can utilize described small molecules then, finally causes the formation of ammonia, acetate and carbonic acid gas.Have been found that fermentation condition is such, dangerous pathogenic agent for example intestinal bacteria (Escherichia coli) and Salmonellas (Salmonella) can not be survived but be eliminated.In addition, diluted as long as the substratum of fermentation does not have, even make tunning stand high shear rate (for example in centrifugal process), tunning does not show the tendency of supporting the pathogenic agent regrowth or producing foul smell yet.

Do not produce the tendency of foul smell although should be noted in the discussion above that described tunning, they contain for example mercaptan compound of the residual chemical odorous that forms in the fermenting process really.Be used as before fertilizer loops back the soil at described product, generally this compounds should be removed from the fermentation cake, purpose is to avoid impairment odorous.The proper method that is used to handle the cake smell comprises and for example superoxide or chlorite reaction of oxygenant.Perhaps, be exposed to air by simple burst and reach time more than 2 days, just can remove described smell via natural composting process.

The present invention also provides the method that is used for producing from described fermented sludge liquid methane gas.The suitable anaerobic digestion that is used for fermented liquid of the present invention comprises all known anaerobic digestions, for example, suspension growth or fixedly the film system among both anaeration in normal temperature digestion and have a liking for warm anaerobic digestion.For the present invention, fixedly the film system for example upper reaches anaerobic mud bed (UASB) reactor be preferred selection, this is because its very short waterpower retention time requirement.

Though the invention provides fermentation cake that is suitable as fertilizer or soil conditioner and the fermented liquid that is suitable for producing methane, accessible is that other purposes of this class product is possible.For example, described fermentation cake can be fed earthworm or further be handled to improve storage and to carry by compost or drying in worm is raised.In addition, fermented liquid can be with acting on for example raw material of the fermentation of bio-degradable plastics of other useful products.In all cases, with regard to fermented liquid and fermentation cake, the ammonia and the tVFA level that surpass 1,500 mg/litre and 3,000 mg/litre respectively are preferred.Described cake preferably has by butt at least 20% solid and is lower than 10, and 000cfu/ restrains dried solid intestinal bacteria.Described fermented liquid preferably has the suspended solids that surpasses 20,000 mg/litre COD and be lower than 3,000 mg/litre.

In a preferred embodiment of the invention, described method further is included in the step of orthophosphoric acid salt contained in the biological waste that separates solid phase and liquid phase precipitation fermentation before.This provides the liquid with high VFA concentration and hypophosphate concentration.

So, the 4th aspect of the present invention provides the method for producing the low liquid of volatile fat acid content height and phosphoric acid salt pollution level, this method comprises the steps: under (1) temperature in mesophilic range, with one section preset time of the fermentation of the biological waste under the anaerobic condition; (2) be settled out orthophosphoric acid salt contained in the described biological waste; (3) separate solid phase and liquid phase subsequently.

Orthophosphoric acid salt is the phosphorus of soluble phosphoric acid salt form.

Adopt any suitable intermediate processing of salt or metal oxide to may be used to cause the precipitation of orthophosphoric acid salt, but preferably adopt magnesium salts (for example magnesium chloride or magnesium oxide) to form to realize struvite.

Preferably, described biological waste be contain greater than 4% solid, at least 5% solid concentrates sewage sludge ideally.

The method of fourth aspect present invention produces VFA, and it has the total VFA of 5000 mg/litre of surpassing and is lower than 50 mg/litre phosphate contaminants, more preferably surpasses the total VFA of 7500 mg/litre and is lower than 15 mg/litre P pollutents.

Now will only specific embodiments of the present invention be described by embodiment.

Embodiment 1.

With raw sewage sludge fill capacity be 1 liter the bottle.After giving the bottle cap loam cake, be allowed to condition under 35 ℃ the temperature in pathogenic agent and reduced in the step fermentation 4 days.The sample of fermented sludge is dewatered and the sample of generation fermentation cake and fermented liquid.

Experimental results reduction is in following table 1:

Table 1

The sample of process stream	Pathogenic agent reduces before the step	Pathogenic agent reduces after the step	Fermented liquid	The fermentation cake
The sample of process stream	Pathogenic agent reduces before the step	Pathogenic agent reduces after the step	Fermented liquid	The fermentation cake	Dry weight, %	7.67	7.50		20.30
Suspended solids, mg/litre			1,200		Dry weight, %	7.67	7.50		20.30
Suspended solids, mg/litre			1,200		COD, mg/litre	5,280	20,120	22,120
TVFA, mg/litre	500	5,500	6,000	6,500	COD, mg/litre	5,280	20,120	22,120
TVFA, mg/litre	500	5,500	6,000	6,500	Ammonia, mg/litre	632	1,189	1,200	2,050
Intestinal bacteria, cfu/ restrains dried solid	1.9×10 ⁷	3.3×10 ²		3.5×10 ²	Ammonia, mg/litre	632	1,189	1,200	2,050
Intestinal bacteria, cfu/ restrains dried solid	1.9×10 ⁷	3.3×10 ²		3.5×10 ²	Salmonellas counting in 2 grams	499	Do not have		Do not have
PH	5.8	5.5	5.5	5.8	Salmonellas counting in 2 grams	499	Do not have		Do not have

Embodiment 2.

Twice of experiment under 32 ℃ leavening temperature among the repetition embodiment 1.In repeating for the first time, make sample fermentation 2 days and make its fermentation 4 days in repeating for the second time.Experimental results reduction is in following table 2:

Table 2

The factor	Primary sludge	Fermentation in 2 days		Fermentation in 4 days
		Fermentation in 2 days		Fermentation in 4 days		Cake	Liquid	Cake	Liquid
		Dry weight, %	6.76	24.05		Cake	Liquid	Cake	Liquid	22.88
Suspended solids, mg/litre		Dry weight, %	6.76	24.05			950		980	22.88
Suspended solids, mg/litre		COD, mg/litre	8,100		21,200		950		980		18,500
TVFA, mg/litre	4,310	COD, mg/litre	8,100		21,200	8,100	8,520	12,300	11,430		18,500
TVFA, mg/litre	4,310	Intestinal bacteria, Cfu/ restrains dried solid	1.1×10 ⁶	4.4×10 ⁴		8,100	8,520	12,300	11,430	2.1×10 ³
Basicity, mg/litre	2,482	Intestinal bacteria, Cfu/ restrains dried solid	1.1×10 ⁶	4.4×10 ⁴		2392		2,485		2.1×10 ³
Basicity, mg/litre	2,482	Ammonia, mg/litre	669	2,100	904	2392		2,485		2,500	1,115
PH	5.3	Ammonia, mg/litre	669	2,100	904		5.3		5.2	2,500	1,115

Embodiment 3.

Processing derives from the fermented liquid (amounting to 0.75 liter) of embodiment 1 to produce methane in desk-top UASB anaerobic reactor.Experimental results reduction is in following table 3:

Table 3

Digestion time (hour)	The output of biogas (L)	Methane content (%)
Digestion time (hour)	The output of biogas (L)	Methane content (%)	24	5.0	65.0
48	5.6	63.5	24	5.0	65.0

Embodiment 4.

Under 42 ℃ temperature, operate the anaerobically fermenting device of physical size in a continuous manner with placed in-line 6 jars.This fermentation container has 150 meters ³The throughput in/sky, average waterpower retention time is 4 days.The whizzer of physical size makes the discharging dehydration of described fermentation container.Experimental results reduction is in following table 4:

Table 4

The factor	Primary sludge	Fermented sludge	The fermentation cake	Fermented liquid
The factor	Primary sludge	Fermented sludge	The fermentation cake	Fermented liquid	Dry weight, %	6.12	4.32	20.5
Volatile solid, %	81.3	76.7			Dry weight, %	6.12	4.32	20.5
Volatile solid, %	81.3	76.7			Suspended solids, mg/litre				2,500
Intestinal bacteria, cfu/ restrains dried solid	2.5×10 ⁷	3.4×10 ²	4.4×10 ²		Suspended solids, mg/litre				2,500
Intestinal bacteria, cfu/ restrains dried solid	2.5×10 ⁷	3.4×10 ²	4.4×10 ²		The existence of Salmonellas in 2 grams	Be	Not	Not
PH	6.1	5.5	6.1	5.8	The existence of Salmonellas in 2 grams	Be	Not	Not
PH	6.1	5.5	6.1	5.8	Basicity, mg/litre	2,280	2,710
Ammonia, mg/litre	477		2,200	1,100	Basicity, mg/litre	2,280	2,710
Ammonia, mg/litre	477		2,200	1,100	TVFA, mg/litre	2,800		14,000	13,500
Acetate, mg/litre	1,260		4,300	4,010	TVFA, mg/litre	2,800		14,000	13,500
Acetate, mg/litre	1,260		4,300	4,010	Propionic acid, mg/litre	838		4,010	4,000
The I-butyric acid, mg/litre	114		420	400	Propionic acid, mg/litre	838		4,010	4,000
The I-butyric acid, mg/litre	114		420	400	The N-butyric acid, mg/litre	288		2,070	2,000
The I-valeric acid, mg/litre	180		780	765	The N-butyric acid, mg/litre	288		2,070	2,000
The I-valeric acid, mg/litre	180		780	765	The N-valeric acid, mg/litre	116		900	950

Embodiment 5.

Adopt the pig slurry as the experiment among the charging repetition embodiment 1.Experimental results reduction is in following table 5:

Table 5

The sample of process stream	Pathogenic agent reduces before the step	Pathogenic agent reduces after the step	Fermented liquid	The fermentation cake
The sample of process stream	Pathogenic agent reduces before the step	Pathogenic agent reduces after the step	Fermented liquid	The fermentation cake	Dry weight, %	7.5	7.30		24.0
Suspended solids, mg/litre			900		Dry weight, %	7.5	7.30		24.0
Suspended solids, mg/litre			900		TVFA, mg/litre	1500	20,500	21,000	20,500
Ammonia, mg/litre	1,030	2,180	2,200	2,550	TVFA, mg/litre	1500	20,500	21,000	20,500
Ammonia, mg/litre	1,030	2,180	2,200	2,550	Intestinal bacteria, cfu/ restrains dried solid	1.9×10 ⁶	1.3×10 ²		2.5×10 ²

Embodiment 6

Repeat the experiment among the embodiment 1.After pathogenic agent reduces step, sample dewaters generation fermentation cake and fermented liquid in the laboratory scale whizzer before, 0.5 liter of Digestive system (that is, anaerobic digestion has minimum biological degradation thing content after producing methane) with contented embodiment 3 dilutes the mud of described fermentation.The general volatile lipid acid (tVFA) that reclaims in fermented liquid is higher by 22% than what obtain from embodiment 1.

Embodiment 7

From the physical size anaerobic fermentation tank of operating by mode described in the embodiment 4, take out the mud sample (2L) of fermentation.This sample is divided into sub-sample a and b.Before making two sample dehydrations, add the MgO powder to sub-sample b.Following table 6 has shown the analysis of liquid sample.

Table 6

The factor	Sub-sample a (no MgO)	Sub-sample b (1 grams per liter MgO)
The factor	Sub-sample a (no MgO)	Sub-sample b (1 grams per liter MgO)	Suspended solids, mg/litre	2,300	2,400
PH	6.1	8.2	Suspended solids, mg/litre	2,300	2,400
PH	6.1	8.2	Ammonia, mg/litre	1,200	1,100
Orthophosphoric acid salt, mg/litre	180	8.5	Ammonia, mg/litre	1,200	1,100
Orthophosphoric acid salt, mg/litre	180	8.5	TVFA, mg/litre	14,000	13,500

From this table as seen, employing MgO precipitation P greatly reduces the orthophosphoric acid salt content in the liquid sample before sample separation, provides thus to can be used for the liquid that the BNR purposes for example is used for taking off from waste water P.

Following embodiment 8-10 has shown how the VFA that exists in the described fermentation waste is oxidized to carbonic acid gas can be used for the less stage of pathogenic agent with generation heat.

Embodiment 8

Referring to the Fig. 1 in the accompanying drawing, shown that the present invention handles the process flow sheet of a method of fork of biological waste.This technology is made up of placed in-line 3 fermenting containers (being labeled as EH1, EH2 and EH3).The volume of each container is 400 meters ³, service temperature is 35 ℃.In operation, first container (EH1) is introduced in sewage sludge feed logistics (logistics 1).Then container EH2 and EH3 are passed through in described feed stream series connection.Make the fermented sludge from container EH3 be divided into two-way, wherein 50% flux and flow direction pressure filter (P) is to produce fermentation cake logistics (logistics 3) and fermented liquid logistics (logistics 4).It is 800 meters that rest part from the fermented sludge of container EH3 is sent to volume ³Aerobic reactor (ATAD), return described reactor oxygen stream (logistics 2) be provided.Biological activity in the ATAD reactor is oxidized to carbonic acid gas and heat with the VFA that exists in the described fermentation waste.Heat in the ATAD reactor makes the temperature of described mud be increased to 55 ℃.The oxidized sludge logistics is circulated to first container (EH1), and this logistics mixes with sewage sludge feed logistics (logistics 1) herein.

Following table 7 has shown the analysis that related parameter is arranged to each logistics.Found that the thermal content of oxidized sludge logistics can keep the service temperature (35 ℃) of described three fermenting containers under situation about importing without any outside heat.

Table 7

Parameter	Logistics 1 charging	Logistics 2 oxygen	Logistics 3 cakes	Logistics 4 filtrates
Parameter	Logistics 1 charging	Logistics 2 oxygen	Logistics 3 cakes	Logistics 4 filtrates	Flow rice ³/ day	100	450	16	84
Temperature ℃	15	15	35	35	Flow rice ³/ day	100	450	16	84
Temperature ℃	15	15	35	35	Dry weight, %	5		25	0
Volatile solid, %	65		57		Dry weight, %	5		25	0
Volatile solid, %	65		57		TVFA, mg/litre	500			8,000

Embodiment 9

Referring to Fig. 2, shown the process flow sheet of a variant of the method for embodiment 8.This technology is made up of placed in-line 3 fermenting containers (being labeled as EH1, EH2 and EH3) equally.The volume of each container is 200 meters ³And service temperature is 35 ℃.In operation, first container (EH1) is introduced in sewage sludge feed logistics (logistics 1).Then, container EH2 and EH3 are passed through in described feed stream series connection.Taking out and it is sent into volume from the fermented sludge of the small part of container EH3 is 50 meters ³Aerobic reactor (ATAD), return this reactor oxygen stream (logistics 2) be provided.Biological activity in the described ATAD reactor is oxidized to carbonic acid gas and heat with the VFA that exists in the described fermentation waste.Heat in the ATAD reactor shifts out and is circulated to the first fermenting container EH1 by heat exchanger (HEX).The oxidized sludge logistics that deducted superfluous heat and excess sludge from fermenting container EH3 are merged and be sent to pressure filter (P) to produce fermentation cake logistics (logistics 3) and fermented liquid logistics (logistics 4).

Following table 8 has shown the analysis that related parameter is arranged to each logistics.Found that the thermal content of oxidized sludge logistics can keep the service temperature (35 ℃) of described three fermenting containers under situation about importing without any outside heat.

Table 8

Parameter	Logistics 1 charging	Logistics 2 oxygen	Logistics 3 cakes	Logistics 4 filtrates
Parameter	Logistics 1 charging	Logistics 2 oxygen	Logistics 3 cakes	Logistics 4 filtrates	Flow rice ³/ day	100	465	16	84
Temperature ℃	15	15	35	35	Flow rice ³/ day	100	465	16	84
Temperature ℃	15	15	35	35	Dry weight, %	5		25	0
Volatile solid, %	65		55		Dry weight, %	5		25	0
Volatile solid, %	65		55		TVFA, mg/litre	500			12,000

Embodiment 10

Referring to Fig. 3, shown the process flow sheet of the another kind of variant of the previous method that is used to handle biological waste.This technology is made up of placed in-line 3 fermenting containers (being labeled as EH1, EH2 and EH3).The volume of each container is 200 meters ³And service temperature is 35 ℃.In operation, first fermenting container (EH1) is introduced in sewage sludge feed logistics (logistics 1).Then, container EH2 and EH3 are passed through in described feed stream series connection.For the first container EH1 provides oxygen stream (logistics 2), the time is 12 hours at the most every day.Biological activity in first container (EH1) is oxidized to carbonic acid gas and heat with the VFA that exists in the described fermentation waste.The heat that produces in first container (EH1) remains on 35 ℃ with its content.So the described first container EH1 serves as fermentation container in portion of time, portion of time is served as aerobic reactor.Fermented sludge from fermenting container EH3 is sent to pressure filter (P) so that fermentation cake logistics (logistics 3) and fermented liquid logistics (logistics 4) to be provided.

The analysis that related parameter is arranged that following table 9 shows each logistics.Found that the heat that oxidation produced of VFA in the first container EH1 can keep the temperature (35 ℃) of three fermenting containers under situation about importing without any outside heat.

Table 9

Parameter	Logistics 1 charging	Logistics 2 oxygen	Logistics 3 cakes	Logistics 4 filtrates
Parameter	Logistics 1 charging	Logistics 2 oxygen	Logistics 3 cakes	Logistics 4 filtrates	Flow rice ³/ day	100	450	16	84
Temperature ℃	15	15	35	35	Flow rice ³/ day	100	450	16	84
Temperature ℃	15	15	35	35	Dry weight, %	5		25	0
Volatile solid, %	65		55		Dry weight, %	5		25	0
Volatile solid, %	65		55		TVFA, mg/litre	500			10,000

Claims

1. handle the method for biological waste, this method comprises the steps: under (i) temperature in mesophilic range, in the pathogenic agent minimizing stage,, and (ii) separate solid phase and liquid phase subsequently to produce fermentation cake and fermented liquid under anaerobic with one section preset time of biological waste fermentation.

2. as the method for the processing biological waste of asking for protection in the claim 1, wherein to primary, nonvaccinated refuse carry out described fermentation step in fact.

3. as the method for the processing biological waste of asking for protection in claim 1 or the claim 2, wherein before fermentation the solids content of described refuse in 3 to 15% scope.

4. as the method for the processing biological waste of asking for protection in the claim 1,2 or 3, the temperature that wherein is used for fermentation stage is in 25 ℃ to 46 ℃ scope.

5. as the method for the processing biological waste of asking for protection in the claim 4, the temperature that wherein is used for fermentation stage is in 32 ℃ to 42 ℃ scope.

6. the method for the processing biological waste of asking for protection in each as claim 1 to 5, wherein said fermentation time is from about 1 day to about 6 days.

7. as the method for the processing biological waste of asking for protection in the claim 6, wherein said fermentation time is between 2 days and about 5 days.

8. the method for the claim processing biological waste of asking for protection in each as described above wherein uses placed in-line many reactors to operate described fermentation step in a continuous manner.

9. the claim method of asking for protection in each as described above; further comprise: during the described pathogenic agent minimizing stage, remove the described fermentation waste of small part, air/oxygen is added removed refuse and the thermal conductance that will therefrom produce to the refuse that experiences fermentation.

10. the method for asking for protection in each as claim 1 to 8 wherein is added in the described biological waste oxygen or air to produce heat during described fermentation step at set intervals.

11. the method as the processing biological waste of asking for protection in the claim 9 further comprises: the described oxidized fermentation waste that has removed heat is combined with other fermentation waste, be used for follow-up separation.

12. the method for the claim processing biological waste of asking for protection in each as described above, the method for wherein separating solid phase and liquid phase are selected from the group of being made up of centrifugal, belt press and pressure filter.

13. the method for the claim processing biological waste of asking for protection in each as described above further is included in the step of the biological waste of the described fermentation of pre-treatment before the described solid-liquid separation.

14. the method for the claim processing biological waste of asking for protection in each as described above, further be included in before the described pathogenic agent minimizing stage, during or use the step of the described biological waste of wastewater dilution afterwards.

15. the method for the claim processing biological waste of asking for protection in each as described above further comprises the step that digests described separated fermented liquid with anaerobic digestion.

16. the method for the claim processing biological waste of asking for protection in each as described above further is included in and makes the sedimentary step of any orthophosphoric acid salt contained in the biological waste of described fermentation before separating solid phase and liquid phase.

17., wherein magnesium salts is added in the refuse of described fermentation to be settled out described orthophosphoric acid salt as the method for the processing biological waste of asking for protection in the claim 16.

18., wherein magnesium oxide is added in the refuse of described fermentation to be settled out described orthophosphoric acid salt as the method for the processing biological waste of asking for protection in the claim 16.

19. the method for the processing biological waste of asking for protection in each as claim 16 to 18, the VFA of wherein said fermented liquid surpasses 5000 milligrams of total VFA/ liters, and phosphoric acid salt pollutes and is lower than 50 mg/litre.

20. the fermentation cake that produces by each method of claim 1 to 14.

21. the fermentation cake of asking for protection in the claim 20 is as the purposes of soil and fertilizer.

22. the fermented liquid that produces by each method of claim 1 to 19.

23. the fermented liquid of asking for protection in the claim 22 is used to produce the purposes of methane gas.

24. contain the fermentation cake at least 15% solid biological waste source by butt, it contains the ammonia that surpasses 500 mg/litre, surpasses the general volatile lipid acid (tVFA) of 1,000 mg/litre and be lower than 100,000cfu/ restrains dried solid intestinal bacteria.

25. as the fermentation cake of asking for protection in the claim 24; wherein this fermentation cake has by butt 20% solid at least, contains the ammonia that surpasses 1000 mg/litre, the tVFA content with at least 3000 mg/litre; and intestinal bacteria to be being lower than 10, and 000cfu/ restrains dried solid amount and exists.

26. the fermented liquid in biological waste source, it contains the COD that surpasses 10,000 mg/litre, surpasses the ammonia of 500 mg/litre, surpasses the tVFA of 1,000 mg/litre and the suspended solids that is lower than 5,000 mg/litre.

27. as the fermented liquid of asking for protection in the claim 26; wherein said fermented liquid contains at least 20; the ammonia of the COD of 000 mg/litre, at least 1500 mg/litre has the tVFA content of at least 3000 mg/litre and has the suspended solids content that is lower than 3000 mg/litre.

28. produce the method for the low liquid of volatile fat acid content height and phosphoric acid salt pollution level, this method comprises the steps: under (1) temperature in mesophilic range, under anaerobic with one section preset time of biological waste fermentation; (2) be settled out orthophosphoric acid salt contained in the described biological waste; (3) separate solid phase and liquid phase subsequently.