CN104766133A - Comprehensive optimization method for small biomass methane combined supply system of cooling, heating and power - Google Patents

Abstract

The invention discloses a comprehensive optimization method for a small biomass methane combined supply system of cooling, heating and power. According to the method, for a given user capable of generating methane, the annual hourly cooling heating and power load requirement of the given user in a typical meteorological year is simulated, and an annual cooling heating and power load curve of a building is obtained; variable working condition characteristics of a main device of the combined supply system of cooling heating and power are designed; the small biomass methane combined supply system of cooling heating and power is constructed and designed; the optimization variable of the small biomass methane combined supply system of cooling heating and power is determined, the parameters of other devices in the small biomass methane combined supply system of cooling heating and power are set with the energy saving rate, the cost recovery rate and the emission benefits relative to a traditional separated supply system as the comprehensive target; optimization restraint conditions are determined; an optimization design target function is set up; the optimization design target function is worked out, the optimization variable is obtained, and the optimal configuration of other devices of the system is obtained. The method is simple and practical and is suitable for engineering optimization design of various small biomass methane combined supply systems of cooling heating and power through cooperation with the building energy consumption analysis theory.

Description

A kind of small-sized biomass biogas cooling heating and power generation system comprehensive optimization method

Technical field

The present invention relates to energy technology field, particularly relate to a kind of small-sized biomass biogas cooling heating and power generation system comprehensive optimization method.

Background technology

China is as large agricultural country, there is quite abundant Biomass Energy Resources, the resource that can be used for producing biogas every year about amounts to 2.5 hundred million tons of standard coal equivalents, equivalent biogas about 1990 billion cubic meter can be transformed, amount to rock gas 1200 billion cubic meter, be equivalent to 93% of China's Natural Gas Consumption Using 1290 billion cubic meter in 2011, calculate according to the totals energy consumption of 2011 (34.8 hundred million tons of standard coal equivalents), the proportion that Chinese Gas Energy Source is consumed is improved about 7% by biogas development.And biogas is as the typical biogas regenerative resource of one, there is the advantages such as calorific value is high, Air-pollution From Combustion is little, 1 cubic metre of complete Combustion Energy of biogas produces the heat being equivalent to 0.7 kilogram of stone coal and providing, utilize marsh gas power generation not only can solve electricity shortage problem, can reduce again methane isothermal chamber gas purging, purify air environment.

But a undisputable fact is, the a large amount of biomass resource of current China fails to realize rationally utilizing efficiently, if rural area biomass marsh gas is mostly only for peasant household's cooking, all the other times are then in idle state, cause the significant wastage of equipment, fund and resource.Cooling heating and power generation system is a kind of supply system be based upon on cascaded utilization of energy conceptual foundation, its maximum feature can realize comprehensive cascade utilization to the heat energy of different grade, complete generating, refrigeration and heat supply (comprising for warm hot water) three processes simultaneously, meet hot and cold, the electric demand of user on the spot, thus reduce the transmission loss of remote energy supply, improve economic results in society and efficiency of energy utilization greatly.Especially the biogas cooling heating and power generation system of tens of kilowatt level is applicable to the demand of China's biomass resource distributing, small-scale application just, its electric power sent can meet handicraft, irrigation and drainage and backwoodsman household electricity, also can alleviate the problem of the difficult and the local pollution of the environment of rural area heat supply greatly simultaneously, to promote agricultural restructuring and building a New Socialist Countryside significant.

Obviously, the demand of China to tens of multikilowatt biogas supply of cooling, heating and electrical powers distributing-supplying-energy system is very urgent, and quantity required is huge.And co-feeding system is as a kind of complicated supply system of Poly-generation, composition structure and operational mode of a great variety, simultaneously also along with building loading real-time change, thus make its design problem become very complicated, improperly will cause many drawbacks such as inefficiency and investment waste once design.

Through finding the retrieval of the open source literature of prior art, as publication number be the patent of CN 1945472 with expense and energy consumption for optimization aim, propose a kind of centralized optimization control method of cooling heating and power generation system, achieve the control to terminal device operational factor; Application number be 201010147996.0 patent discloses a kind of cooling heating and power generation system efficiency Optimal Scheduling, be calculated as the plan of exerting oneself of each energy unit of basic Optimized Operation with load prediction and relevant optimization, and then achieve the equilibrium of supply and demand of cool and thermal power energy.Although said method all effectively improves co-feeding system performance, also exist certain not enough simultaneously:

1) not relating to for small-sized cold chp system, is especially the co-feeding system Optimum design of engineering structure of the energy with living beings.On the one hand, existing cooling heating and power generation system is mostly still main energy sources with rock gas, but belongs to fossil fuel due to rock gas, therefore is difficult to the advantage at utmost showing distributing-supplying-energy system energy-saving and emission-reduction.On the other hand, along with family expenses and small commercial co-feeding system day by day rise, tens of kilowatt level combustion engine is more concerned by people.And as the core of this type of small-sized co-feeding system, its in unit parameter, efficiency and waste heat amount etc. with big-and-middle-sized unit difference all to some extent, and then have influence on type selecting and the Capacity Selection of the follow-up equipment that matches with it, also just caused overall system design scheme also by difference in the past.

2) co-feeding system is the complicated energy resource system be composed of multiple units, and wherein the input-output characteristic of each unit, particularly key equipment has very important impact to entire system performance.But due to each component modeling difficulty, the reasons such as workload is large cause Optimization Design conventional at present only to be started with energy flow function, do not relate to the dynamic perfromance of each equipment.

Summary of the invention

Object of the present invention is exactly to solve the problem, and provides a kind of small-sized biomass biogas cooling heating and power generation system comprehensive optimization method, to divide for system for reference object, and energy conservation rate, cost recovery rate and CO ₂reduction of discharging rate is integration objective, establish the small-sized biomass biogas internal combustion engine generator group cooling heating and power generation system Optimized model taking into account equipment Study on Variable Condition Features, and solve obtain internal combustion engine generator pool-size, start and stop coefficient and electricity refrigeration proportion, achieve the optimal design of small-sized biomass biogas co-feeding system.

To achieve these goals, the present invention adopts following technical scheme:

A kind of small-sized biomass biogas cooling heating and power generation system comprehensive optimization method, comprises the following steps:

Step one: for the given user that can produce biogas, simulate its typical meteorological year the whole year by time cool and thermal power workload demand, obtain building annual cool and thermal power load curve;

Step 2: the Study on Variable Condition Features of design co-feeding system major equipment;

Step 3: tectonic sieving small-sized biomass biogas cooling heating and power generation system;

Step 4: the optimized variable determining small-sized biomass biogas cooling heating and power generation system, comprising:

The capacity of internal combustion engine generator group, internal combustion engine generator group start and stop coefficient and electricity refrigeration are than three variablees, and wherein electricity refrigeration is than being defined as:

$\mathrm{\θ}=\frac{Q_{\mathrm{ch}}}{Q_{\mathrm{ch}}+Q_{\mathrm{ab}}}$

In formula: Q _chand Q _abrepresent the electric refrigerating capacity of electrical chillers and the absorption refrigeration amount of absorption refrigeration unit respectively;

Except internal combustion engine generator group and refrigeration unit, according to the CO2 emission coefficient of investigation situation set device efficiency value, combustion gas and grid generation, algorithm parameter and energy prices;

Step 5: determine to optimize constraint condition; Set up optimal design objective function, divide the fractional energy savings of the system of confession, cost recovery rate with relatively traditional and reduce discharging benefit for integration objective; Solving-optimizing design object function obtains the optimized variable in described step 4, obtains the allocation optimum of system miscellaneous equipment further.

In described step 2, co-feeding system major equipment comprises internal combustion engine generator group, lithium-bromide absorption-type refrigerating machine and electric refrigerating machine;

The concrete grammar of the Study on Variable Condition Features design of co-feeding system major equipment is: determine every efficiency parameters according to internal combustion engine generator group part load ratio; The hot water temperature produced according to waste heat recovery and cooling water temperature determination lithium-bromide absorption-type refrigerating machine maximum cooling capacity; Electric refrigerating machine maximum cooling capacity is calculated according to setting chilled water temperature and cooling water temperature; Study on Variable Condition Features curve or face is obtained by spline method matching.

In described step 3, small-sized biomass biogas cooling heating and power generation system comprises biogas pre-processing device, gas-holder, internal combustion engine generator group, heat interchanger, donkey boiler, absorption refrigeration unit, electrical chillers and bulk power grid electric power system;

The biogas that biomass anaerobic fermentation produces enters gas-holder after marsh gas purifying equipment, generate electricity for driving internal combustion engine generator group, internal combustion engine generator group exports electric energy supply user, electric refrigerating machine, cooling tower and other equipment electricity consumptions, is auxiliary electric power supply with bulk power system simultaneously; Adopt the heat interchanger abundant Mist heat recovering of water circulation system series system and jacket water waste heat; Reclaim the single-effective absorption refrigerating machine that heat is applicable to drive low capacity; Described donkey boiler is also fuel with biogas, for the heat demand vacancy of replenishment system; Described electrical chillers coordinates Absorption Refrigerator to be user's cooling.

In described step 5,

The defining method optimizing constraint condition is: in optimization computation process, ensure the balance of internal system cool and thermal power energy, and set the bound of optimized variable, meet the Study on Variable Condition Features of equipment.

In described step 5,

Optimal design objective function is:

max V＝ω ₁PESR+ω ₂ACR+ω ₃CO ₂ERR

Wherein $\mathrm{PESR}=\frac{G_{\mathrm{SP}}-G_{\mathrm{CCHP}}}{G_{\mathrm{SP}}},{\mathrm{CO}}_2\mathrm{ERR}=\frac{{\mathrm{CO}}_2{E}_{\mathrm{SP}}-{\mathrm{CO}}_2{E}_{\mathrm{CCHP}}}{{\mathrm{CO}}_2{E}_{\mathrm{SP}}},$

$\mathrm{ACR}=\frac{\underset{d=i}{\overset{365}{\mathrm{\Σ}}}\underset{h=j}{\overset{24}{\mathrm{\Σ}}}((E_{\mathrm{sp},\mathrm{ij}}-E_{\mathrm{grid},\mathrm{ij}})p_{\mathrm{ej}}+(G_{\mathrm{sp},\mathrm{ij}}-G_{\mathrm{gas},\mathrm{ij}})p_f)}{R_{\mathrm{CCHP}}-R_{\mathrm{SP}}}$

In formula, PESR is co-feeding system energy conservation rate; ACR for co-feeding system by economize energy expense with reclaim increase equipment purchasing cost needed for the time limit, i.e. the annual cost recovery; CO ₂eRR is the carbon dioxide discharge-reduction rate of co-feeding system; ω ₁, ω ₂, ω ₃represent PESR, ACR, CO respectively ₂the weight coefficient of EER, and meet 0≤ω ₁, ω ₂, ω ₃≤ 1, and ω ₁+ ω ₂+ ω ₃=1; Max V represents that integrated objective function maximizes; G _cCHP, G _sPbe expressed as co-feeding system and divide for the annual total energy consumption of system, CO ₂e _cCHPfor co-feeding system year CO2 emissions, CO ₂e _sPrepresent point year CO2 emissions supplying system; G _gasrepresent total combustion gas energy that co-feeding system consumes, E _gridfor co-feeding system is from the purchase of electricity of bulk power grid; R _cCHP, R _sPrepresent co-feeding system and the equipment investment cost of dividing for system respectively; E _spfor dividing the power consumption for system; I and j represent respectively day and hour; p _ejfor tou power price, the p in j moment _fit is then fuel price.

According to the optimized variable obtained in described step 4, further combined with the capacity of customer charge determination absorption refrigeration unit, heat interchanger, donkey boiler and electric refrigerating machine, contrast this small-sized biomass biogas cooling heating and power generation system and rock gas co-feeding system at annual air consumption, energy cost and CO ₂the difference of discharge capacity aspect.

Beneficial effect of the present invention:

To divide for system for reference object, energy conservation rate, cost recovery rate and CO ₂reduction of discharging rate is integration objective, establish the small-sized biomass biogas internal combustion engine generator group cooling heating and power generation system Optimized model taking into account equipment Study on Variable Condition Features, and solve obtain internal combustion engine generator pool-size, start and stop coefficient and electricity refrigeration proportion, achieve the optimal design of small-sized biomass biogas co-feeding system.The method is simple and easy to do, in conjunction with building energy consumption analysis theories, is applicable to different types of small-sized cold chp system Optimum design of engineering structure.

Accompanying drawing explanation

Fig. 1 is small-sized biomass biogas internal combustion engine generator group cooling heating and power generation system structural representation;

Fig. 2 takes into account energy-conservation, economy, the feature of environmental protection small-sized cold chp system optimal design process flow diagram;

Fig. 3 is Study on Variable Condition Features matched curve or the face of internal combustion engine generator group and refrigeration unit; Wherein, scheming (a) is internal combustion engine generator group thermal efficiency curve; Figure (b) is internal combustion engine generator group generating efficiency curve, figure (c) is the situation of change of the Absorption Refrigerator capacity coefficient ratio of rated capacity (active volume with), and figure (d) is the situation of change of the electric refrigerating machine capacity coefficient ratio of rated capacity (active volume with).

Wherein, 1, internal combustion engine generator group; 2, jacket water heat interchanger; 3, flue gas heat-exchange unit; 4, donkey boiler; 5, electric refrigerating machine; 6, Absorption Refrigerator; 7, cooling tower; 8, user; 9, biogas pre-processing device; 10, gas-holder.

In figure, each symbol is: E _grid, E _pgurepresent the generated energy of electrical network purchase of electricity and genset respectively; E _{ch_CCHP}, E _{pa_CCHP}represent electric refrigerating machine and the peripherals power consumption of co-feeding system; E is instantaneous electric load; G _pgurepresent the combustion gas energy that unit consumes; Q _chfor electric refrigerating machine refrigerating capacity; Q _abfor Absorption Refrigerator refrigerating capacity; C is the instantaneous cold demand of user; Q _jwjacket water waste heat, Q _exhfume afterheat, Q _refor total waste heat amount that unit reclaims; H represents user's transient thermal load demand; Q _brepresent waste heat boiler heating load; Q _exfor the redundancy heat that system produces; Q _bchrepresent the heat driving lithium-bromide absorption-type refrigerating machine; G _binput energy needed for gas fired-boiler; G _pgurepresent the combustion gas energy that unit consumes; G _cCHPrepresent the total energy that co-feeding system consumes.

Embodiment

Below in conjunction with accompanying drawing and embodiment, the invention will be further described.

Fig. 1 is small-sized biomass biogas cooling heating and power generation system structural drawing of the present invention.Be made up of internal combustion engine generator group 1, jacket water heat interchanger 2, flue gas heat-exchange unit 3, donkey boiler 4, electric refrigerating machine 5, Absorption Refrigerator 6, cooling tower 7, user 8, biogas pre-processing device 9, gas-holder 10, biogas pre-processing device 9 is marsh gas purifying equipment.

Specific works process is as follows:

(1) biogas that biomass anaerobic fermentation produces passes into gas-holder 10 and stores after pre-processing device 9, when co-feeding system works for driving internal combustion engine generator group 1 to generate electricity, and supply building, electrical chillers 5, cooling tower 7 and other equipment use; Met by bulk power grid power purchase when generated energy is not enough;

(2) waste heat that biogas supply internal combustion engine generator group 1 produces while generating electricity is connected by jacket water heat interchanger 2 and flue gas heat-exchange unit 3 and is reclaimed, and for driving Absorption Refrigerator 6 during heat summer of recovery, directly supplies user 8 during winter; Supplemented by donkey boiler 4 when provided shortage of heat;

(3) internal combustion engine generator group 1 presses the operation of electric load size, produces without unnecessary electricity, and the waste heat produced directly is discharged and can be supplied nearby users.

Fig. 2 is overall realization flow of the present invention, and concrete steps are as follows:

1, by 8760 hours whole years in simulation of energy consumption software simulation given regional energy supply object typical meteorological year by time cool and thermal power load data, by hour in units of draw year load variations curve;

2, the comprehensive factor such as local energy resources price and policy, design tradition point supplies energy resource system, in order to the object of reference as co-feeding system optimal design; Under the prerequisite of meeting consumers' demand, calculate power consumption and the air consumption of this system whole year, obtain expending energy expenditure and CO year simultaneously ₂discharge capacity;

3, based on TRNSYS simulation of energy consumption emulation platform, tectonic sieving takes into account the small-sized biomass biogas internal combustion engine generator group cooling heating and power generation system of equipment Study on Variable Condition Features, with tradition relatively point for system fractional energy savings, year the cost recovery and CO ₂reduction of discharging rate is integration objective, the key parameter of the structure of optimal design co-feeding system, capacity and the method for operation.And by annual air consumption, energy cost and CO ₂start with and this system and rock gas co-feeding system to be contrasted in the aspects such as discharge capacity.Idiographic flow is as follows:

3.1 structure small-sized biomass biogas cooling heating and power generation systems, comprise marsh gas purifying equipment, gas-holder, internal combustion engine generator group, heat interchanger, donkey boiler, absorption refrigeration unit, electrical chillers and bulk power grid electric power system, specific works process is as follows: the biogas that (1) biomass anaerobic fermentation produces, through the generating of pre-processing device rear drive internal combustion engine generator group, supplies building, electrical chillers and other equipment use; Met by bulk power grid power purchase when generated energy is not enough; (2) waste heat produced while the generating of biogas supply internal combustion engine generator group is reclaimed by jacket water heat interchanger and flue gas heat-exchange unit series connection, for driving Absorption Refrigerator during heat summer of recovery, directly supplies user during winter; Supplemented by donkey boiler when provided shortage of heat;

The selection of 3.2 small-sized biomass biogas cooling heating and power generation system optimized variables and determining: comprise the capacity of internal combustion engine generator group, internal combustion engine generator group start and stop coefficient and electricity refrigeration than three variablees, wherein electricity refrigeration is than being defined as:

$\mathrm{\θ}=\frac{Q_{\mathrm{ch}}}{Q_{\mathrm{ch}}+Q_{\mathrm{ab}}}$

In formula: Q _chand Q _abrepresent electric refrigerating capacity and absorption refrigeration amount respectively;

By caloric restriction more than small-sized internal combustion genset, be only suitable for mating the lower single-effective absorption refrigerating machine of COP (coefficient of refrigerating performance), this will reduce co-feeding system performance, therefore in scheme, adopt the electric refrigerating machine of high COP to coordinate Absorption Refrigerator to realize mixing cooling, to take into account UTILIZATION OF VESIDUAL HEAT IN and refrigerating efficiency;

3.3 by the Study on Variable Condition Features curve of cubic spline interpolation matching major equipment or face, as shown in Figure 3:

1. in actual motion, the parameter such as the thermal efficiency and generating efficiency of internal combustion engine generator group changes with the change of part load ratio PLR, and as Fig. 3 (a), 3 (b), wherein clearly show the unit parameter when PLR is lower all has obvious decline; Set the start and stop coefficient of unit, namely when PLR normally works higher than unit during this coefficient for this reason; Otherwise then out of service, and by bulk power grid power purchase and donkey boiler energy supply.The co-feeding system overall performance caused due to unit light running can be avoided like this to reduce;

2. refrigeration machine available max cap. under different operating mode is also not quite similar.For hot water lithium bromide absorbing unit, its maximum available affects by thermal source and cooling water temperature.The maximum available of electric refrigerating machine is then determined by chilled water and cooling water temperature.Fig. 3 (c), 3 (d) give the situation of change of refrigerating machine capacity coefficient after the data fitting ratio of rated capacity (active volume with), can calculate the maximum available refrigerant amount of Absorption Refrigerator and electric refrigerating machine under each operating mode in conjunction with rated capacity;

The determination of 3.4 optimization constraint conditions:

1. set the bound of optimized variable, meet the Study on Variable Condition Features of equipment;

2. energy equilibrium constraint condition, namely keeps the energy equilibrium of each parts in co-feeding system.

3.5 set up optimal design objective function:

maxV＝ω ₁PESR+ω ₂ACR+ω ₃CO ₂ERR

Wherein the energy conservation rate of co-feeding system is defined as:

$\mathrm{PESR}=\frac{G_{\mathrm{SP}}-G_{\mathrm{CCHP}}}{G_{\mathrm{SP}}}$

G in formula _cCHP, G _sPbe expressed as co-feeding system and divide for the annual total energy consumption of system.

Co-feeding system by economize energy expense with reclaims increase equipment purchasing cost needed for the time limit, namely the annual cost recovery is defined as:

$\mathrm{ACR}=\frac{\underset{d=i}{\overset{365}{\mathrm{\Σ}}}\underset{h=j}{\overset{24}{\mathrm{\Σ}}}((E_{\mathrm{sp},\mathrm{ij}}-E_{\mathrm{grid},\mathrm{ij}})p_{\mathrm{ej}}+(G_{\mathrm{sp},\mathrm{ij}}-G_{\mathrm{gas},\mathrm{ij}})p_f)}{R_{\mathrm{CCHP}}-R_{\mathrm{SP}}}$

G in formula _gasrepresent total combustion gas energy that co-feeding system consumes, E _gridfor co-feeding system is from the purchase of electricity of bulk power grid; R _cCHP, R _sPrepresent co-feeding system and the equipment investment cost of dividing for system respectively, wherein comprise biogas pre-processing device and biogas storage tank investment; p _ejfor tou power price, the p in j moment _fit is then fuel price.

The CO of co-feeding system ₂reduction of discharging rate is then defined as:

${\mathrm{CO}}_2\mathrm{ERR}=\frac{{\mathrm{CO}}_2{E}_{\mathrm{SP}}-{\mathrm{CO}}_2{E}_{\mathrm{CCHP}}}{{\mathrm{CO}}_2{E}_{\mathrm{SP}}}$

CO in formula ₂e _cCHPfor co-feeding system year CO2 emissions, CO ₂e _sPthen represent point year CO2 emissions supplying system;

ω ₁, ω ₂, ω ₃represent PESR, ACR, CO respectively ₂the weight coefficient of EER, and meet 0≤ω ₁, ω ₂, ω ₃≤ 1, and ω ₁+ ω ₂+ ω ₃=1, choose equal weight Y-factor method Y here, namely think that three aspects are of equal importance, ω ₁=ω ₂=ω ₃=1/3.

3.6 co-feeding system optimal design parameter settings: except internal combustion engine generator group and refrigeration unit, according to investigating situation set device efficiency value, the CO2 emission coefficient of combustion gas and grid generation, algorithm parameter and energy prices etc.

Solving of 3.7 Optimized models:

Suitable optimized algorithm is selected to solve this optimization problem, obtain optimum internal combustion engine generator pool-size, start and stop coefficient and electricity refrigeration ratio, determine the capacity of the equipment such as absorption refrigeration unit, heat interchanger, gas fired-boiler and electric refrigerating machine further combined with customer charge situation, complete small-sized biomass biogas cooling heating and power generation system optimal design.

Now for Jinan plant individual layer office building, the effect of Optimization Design of the present invention is described:

1,10m is had in this plant ³methane-generating pit, daily output methane quantity is about 400m ³, wherein certain individual layer office building is divided into 6 regions, and the total area is about 486m ², whole height 3.2m; Lighting load is 11W/m ², equipment electricity consumption 13W/m ², density of personnel is 0.1 people/m ².Obtained the hourly load data of annual 8760 hours by simulation of energy consumption software for calculation, maximum electric load 39kW, maximum cold, thermal load are 72kW.

2, supply System's composition as follows dividing of reference: the thermal load needed for building is from gas fired-boiler, and summer is then responsible for refrigeration by electrical chillers; Building electricity consumption, electric refrigerating machine and other equipment electric energy are supplied by municipal electrical network from coal-burning power plant.If grid generation efficiency is 0.35, transfer efficiency 0.92, electrical chillers COP is 4.0, and boiler thermal output is 0.85, and calculating the score for system consumption whole year energy total amount is 4.11*10 ⁵kWh.

3, tou power price is adopted to calculate, specifically be set as peak value (11:00 ~ 14:00,18:00 ~ 23:00) be 1.070 yuan/kWh, level values (7:00 ~ 11:00,14:00 ~ 18:00) is 0.687 yuan/kWh valley (23:00 ~ 7:00) is then 0.360 yuan/kWh; Local biogas price and Gas Prices are respectively 0.218 yuan/kWh, 0.252 yuan/kWh; Meanwhile, the CO2 emission factor of biogas, rock gas and electrical network power purchase is then respectively 196g/kWh, 220g/kWh, 968g/kWh.

Particle cluster algorithm Optimization Solution is adopted to obtain: internal combustion engine generator pool-size N _pgu=23kW, Unit Commitment factor alpha=0.22, electricity refrigeration is than θ=0.12.

According to above-mentioned optimum results, calculating biogas co-feeding system year total energy consumption is 2.76*10 ⁵kWh; Air consumption is 36107m ³; Energy consumption cost is 46578 yuan; CO ₂total emission volumn is 75474kg;

For the performance of system, a year energy conservation rate 32.8% is respectively to score, year the cost recovery 33.7%, CO ₂reduction of discharging rate 25.6%; As can be known from the results, optimal design energy-conservation, economical with reduction of discharging three in all have remarkable result.

Calculating the annual air consumption of rock gas co-feeding system is 23183m ³; Energy consumption cost is 55015 yuan; CO ₂total emission volumn is 81702kg.As can be seen here, although to adopt after biomass marsh gas co-feeding system year air consumption comparatively rock gas time increase 55.7%, meanwhile year total energy cost and CO ₂discharge capacity but reduces 15.3% and 7.3% respectively.Namely comparing rock gas, take biomass marsh gas as the economy that the energy effectively can improve cooling heating and power generation system.

By reference to the accompanying drawings the specific embodiment of the present invention is described although above-mentioned; but not limiting the scope of the invention; one of ordinary skill in the art should be understood that; on the basis of technical scheme of the present invention, those skilled in the art do not need to pay various amendment or distortion that creative work can make still within protection scope of the present invention.

Claims (6)

1. a small-sized biomass biogas cooling heating and power generation system comprehensive optimization method, is characterized in that, comprise the following steps:

Step one: for the given user that can produce biogas, simulate its typical meteorological year the whole year by time cool and thermal power workload demand, obtain building annual cool and thermal power load curve;

Step 2: the Study on Variable Condition Features of design co-feeding system major equipment;

Step 3: tectonic sieving small-sized biomass biogas cooling heating and power generation system;

Step 4: the optimized variable determining small-sized biomass biogas cooling heating and power generation system, comprising:

The capacity of internal combustion engine generator group, internal combustion engine generator group start and stop coefficient and electricity refrigeration are than three variablees, and wherein electricity refrigeration is than being defined as:

In formula: Q _chand Q _abrepresent the electric refrigerating capacity of electrical chillers and the absorption refrigeration amount of absorption refrigeration unit respectively;

Except internal combustion engine generator group and refrigeration unit, according to the CO2 emission coefficient of investigation situation set device efficiency value, combustion gas and grid generation, algorithm parameter and energy prices;

Step 5: determine to optimize constraint condition; Set up optimal design objective function, divide the fractional energy savings of the system of confession, cost recovery rate with relatively traditional and reduce discharging benefit for integration objective; Solving-optimizing design object function obtains the optimized variable in described step 4, obtains the allocation optimum of system miscellaneous equipment further.

2. a kind of small-sized biomass biogas cooling heating and power generation system comprehensive optimization method as claimed in claim 1, it is characterized in that, in described step 2, co-feeding system major equipment comprises internal combustion engine generator group, lithium-bromide absorption-type refrigerating machine and electric refrigerating machine;

The concrete grammar of the Study on Variable Condition Features design of co-feeding system major equipment is: determine every efficiency parameters according to internal combustion engine generator group part load ratio; The hot water temperature produced according to waste heat recovery and cooling water temperature determination lithium-bromide absorption-type refrigerating machine maximum cooling capacity; Electric refrigerating machine maximum cooling capacity is calculated according to setting chilled water temperature and cooling water temperature; Study on Variable Condition Features curve or face is obtained by spline method matching.

3. a kind of small-sized biomass biogas cooling heating and power generation system comprehensive optimization method as claimed in claim 1, it is characterized in that, in described step 3, small-sized biomass biogas cooling heating and power generation system comprises biogas pre-processing device, gas-holder, internal combustion engine generator group, heat interchanger, donkey boiler, absorption refrigeration unit, electrical chillers and bulk power grid electric power system;

The biogas that biomass anaerobic fermentation produces enters gas-holder after marsh gas purifying equipment, generate electricity for driving internal combustion engine generator group, internal combustion engine generator group exports electric energy supply user, electric refrigerating machine, cooling tower and other equipment electricity consumptions, is auxiliary electric power supply with bulk power system simultaneously; Adopt the heat interchanger abundant Mist heat recovering of water circulation system series system and jacket water waste heat; Reclaim the single-effective absorption refrigerating machine that heat is applicable to drive low capacity; Described donkey boiler is also fuel with biogas, for the heat demand vacancy of replenishment system; Described electrical chillers coordinates Absorption Refrigerator to be user's cooling.

4. a kind of small-sized biomass biogas cooling heating and power generation system comprehensive optimization method as claimed in claim 1, is characterized in that, in described step 5,

The defining method optimizing constraint condition is: in optimization computation process, ensure the balance of internal system cool and thermal power energy, and set the bound of optimized variable, meet the Study on Variable Condition Features of equipment.

5. a kind of small-sized biomass biogas cooling heating and power generation system comprehensive optimization method as claimed in claim 1, is characterized in that, in described step 5,

Optimal design objective function is:

max V＝ω ₁PESR+ω ₂ACR+ω ₃CO ₂ERR

Wherein

In formula, PESR is co-feeding system energy conservation rate; ACR for co-feeding system by economize energy expense with reclaim increase equipment purchasing cost needed for the time limit, i.e. the annual cost recovery; CO ₂eRR is the carbon dioxide discharge-reduction rate of co-feeding system; ω ₁, ω ₂, ω ₃represent PESR, ACR, CO respectively ₂the weight coefficient of EER, and meet 0≤ω ₁, ω ₂, ω ₃≤ 1, and ω ₁+ ω ₂+ ω ₃=1; Max V represents that integrated objective function maximizes; G _cCHP, G _sPbe expressed as co-feeding system and divide for the annual total energy consumption of system, CO ₂e _cCHPfor co-feeding system year CO2 emissions, CO ₂e _sPrepresent point year CO2 emissions supplying system; G _gasrepresent total combustion gas energy that co-feeding system consumes, E _gridfor co-feeding system is from the purchase of electricity of bulk power grid; R _cCHP, R _sPrepresent co-feeding system and the equipment investment cost of dividing for system respectively; E _spthen for dividing the power consumption for system; I and j represent respectively day and hour; p _ejfor tou power price, the p in j moment _fit is then fuel price.

6. a kind of small-sized biomass biogas cooling heating and power generation system comprehensive optimization method as claimed in claim 1, it is characterized in that, according to the optimized variable obtained in described step 4, further combined with the capacity of customer charge determination absorption refrigeration unit, heat interchanger, donkey boiler and electric refrigerating machine, contrast this small-sized biomass biogas cooling heating and power generation system and rock gas co-feeding system at annual air consumption, energy cost and CO ₂the difference of discharge capacity aspect.