摘要:西气东输工程的东段管道已经开始试运行,天然气在中国能源结构中的比例将越来越大。燃气空调是一种合理利用天然气的方法,还可以降低用电用气的季节不平衡。本文介绍了燃气空调的不同产品形式,并陈述了燃气空调的发展优势。
Abstract: east west to east gas pipeline project pipeline has started trial operation, the gas in the proportion of China's energy structure will be bigger and bigger. Gas air conditioning is a method of rational utilization of natural gas, electricity gas can be reduced by seasonal imbalance. Different product form of gas-fired air conditioning were introduced in this paper, and stated the development of gas air-conditioning.
关键词:燃气空调 能源结构 天然气
Key words: gas natural gas air conditioning energy structure
1.前言
1. Introduction
随着我国经济的发展和人们生活水平不断提高,我国空调器的使用量不断增大。我国的空调器主要是电空调器,随着空调使用量的增大,空调的耗电量也越来越大,因而造成电力紧张,用电的季节峰谷差加大。另一方面,2003年10月1日,西部大开发的标志性工程―西气东输工程东段管道靖边――上海段开始投产试运行,源源不断的天然气开始进入上海和华东地区,2004年元月1日,上海将开始商业供气,天然气在我国能源结构中的比例将越来越大。
With China's economic development and people living standard unceasing enhancement, our country in the use of air conditioner. Air conditioner is mainly electric air-conditioner in our country, with the increase of air conditioning usage, air conditioning power consumption is becoming more and more big, thus causing electricity tension, season of electricity peak valley has widened. On October 1, 2003, on the other hand, the development of the western region of the landmark project, west-east gas project eastern pipeline jingbian-yanshuiguang pipeline - Shanghai began production trial run, a steady stream of gas begin to enter Shanghai and eastern China, after January 1, 2004, Shanghai will start commercial gas, gas ratio of energy structure in our country will become more and more big.
发展燃气空调,既可以缓解由于大量使用电空调器引起的高温季节的电力紧张,又增加了夏季的用气量,可以调节用电用气的季节不平衡。此外,在我国大力发展燃气空调,可以比较合理的消费天然气,适应我国“西气东输”工程的要求,受到国家能源政策的支持,而且燃气空调还具有很好的环保性能。
Development of gas air-conditioning, can alleviate because of a large number of high temperature season power tension caused by the use of electric air conditioner, and increase the summer gas, can adjust electricity gas seasonal imbalance. Developing gas air conditioner, in addition, in our country can be a reasonable consumption of natural gas, adapt to the requirements for "west to east gas pipeline project" in China, and is supported by the national energy policy, and gas air conditioning also has the very good environmental protection performance.
2.燃气空调主要产品种类
2. Gas air conditioning main product categories
燃气空调的种类较多,可以根据不同的使用场合、不同的使用要求来加以选用。根据制冷制热原理和使用目的的不同,燃气空调大致有以下几种产品种类。
Gas air conditioning sort is more, can be used according to different occasions, different use requirement to choose. According to the refrigeration and heating principle and purpose is different, gas air conditioning to roughly the following several kinds of products.
2.1 燃气发动机驱动空调
2.1 gas engine driven air conditioning
由燃气发动机驱动的压缩式空调具有较高的性能系数,因而在燃气空调中以燃气为能源的压缩式冷水机组及热泵机组发展较快。由燃气发动机驱动的压缩式冷水机组及热泵机组与电动压缩机组比较,可无需考虑电力系统的发电效率及输配电效率,因而具有较高的性能系数,是一种既可以燃气为能源又具有较高性能系数的制冷机组。燃气发动机驱动空调通过燃气发动机驱动制冷压缩机,同时回收发动机水夹套中的尾气的废热用于吸收式制冷机或产生热水、蒸气等[1]。燃气发动机驱动空调与电动蒸气压缩式空调相比还具有以下特点: 1)可回收发动机的排热使热泵的输出量增加,还可将回收的排热驱动吸收式制冷机制取冷水; 2)发动机驱动极易进行转速控制,实现能量调节,可保持部分负荷时的高效率; 3)以大气为热源的场合,因发动机的排热基本不受大气影响,即使在严冬,输出热量也变化不大; 4)除霜过程可用发动机的排热加热,对输出热水温度影响较小。
Driven by gas engine compression type air conditioner has high coefficient of performance, and therefore in gas air conditioners with gas as the energy by the rapid development of compression type water chiller and heat pump units. Driven by gas engine compression type water chiller and heat pump units and the electric compressor, can need not consider power system of power generation efficiency and efficiency of power transmission and distribution, thus has a higher coefficient of performance, is a kind of both can gas for energy and has a high performance coefficient of the refrigeration unit. Gas engine driven by gas engine driven air conditioning refrigeration compressor, and recycling of the engine water jacket tail gas waste heat used for absorption chillers or to produce hot water, steam, etc. [1]. Gas engine driven air conditioning and electric steam compression type air conditioner compared also has the following characteristics: 1) the recycled engine exhaust heat increase heat pump's output, but also the recovery of exhaust heat driven absorption refrigerating machine for making cold water; 2) driving to engine speed control, to achieve power adjustment, can keep the partial load efficiency; Occasions, 3) in the atmosphere as heat source of engine exhaust heat basic is not affected by the atmosphere, even in winter, heat output also changed little; 4) the defrosting process engine exhaust heat heating are available, and the output temperature of hot water.
2.2 直燃型吸收式空调机组
2.2 direct absorption type air conditioning unit
直燃吸收式空调机组以天然气、液化石油气、燃油为能源,在高压发生器内燃烧,释放热量,以高温烟气作为加热源,利用吸收式制冷循环的基本原理,制取冷热水,供夏季制冷、冬季采暖用。它结合了吸收式冷水机组与锅炉的优点,具有一机多用的功能。直燃型机组有单冷机组和冷温水机组两种形式:单冷机组只具有制冷功能,在天气炎热时为空调系统提供冷冻水;冷温水机组则具有制冷和采暖的双重功能,既可以提供冷冻水,还可以提供热源以及热水。按照采暖循环的不同方式,冷温水机组又可以分为如下几种类型:1)制冷、采暖专用机:它只能交替地以制冷/采暖方式进行运转,而不能同时具备两种功能;2)同时制冷与采暖型:它在工作时可以同时完成制冷与采暖循环; 3)同时制冷、采暖与供应生活热水型:它的优点是设备利用率高,可以节省机房的面积。
Direct combustion absorption air conditioning unit in natural gas, liquefied petroleum gas, fuel for energy, combustion within the high voltage generator, heat, high temperature flue gas as the heating source, using the basic principle of absorption refrigeration cycle, for making hot and cold water, for summer cooling and winter heating. It combines the advantages of the absorption chiller and boiler, have the function of the multi-usage. Direct units have used by units and different two kinds of forms: single cooler unit with functions of cooling, only in hot weather to provide chilled water for air conditioning system; Different has the dual function of cooling and heating, can provide chilled water, can also provide heat sources and hot water. According to the different means of heating cycle, and different can be divided into the following several types: 1) the refrigeration, heating machine: it can only be alternately operating on the basis of refrigeration/heating, and can't have two functions at the same time; 2) type refrigeration and heating at the same time, it can be done at the same time in work cycle refrigeration and heating; 3) cooling supply, heating and living hot water operated at the same time, it has the advantage of high utilization rate of equipment, can save the area of the room.
2.3 冷热电三联产系统
2.3 cold hot electricity cogeneration system
冷热电三联产系统是一种对燃气进行梯级利用的系统,可以有效的提高一次能源利用率。为了有效利用燃气,不仅要提高耗能设备效率,尽量减少排放热损失,而且要使燃气产生的能量由高温到低温实行多阶段多次利用,也就是按能量品位的高低,安排好功、热和物料热力学能的各种能量之间的合理配合,实现不同形式、不同品位能量的梯级利用,以获得整个系统能量综合利用最佳效果。
Cold and hot electricity cogeneration system is a system of cascade utilization of gas, can effectively improve the utilization rate of energy at a time. In order to effectively use of gas, not only to improve the efficiency of energy consumption equipment, heat loss, decrease as far as possible emissions and to generate energy from high temperature to low temperature gas for multi-stage repeatedly used, namely according to the energy grade of the high and low, arranged work, heat and material thermodynamics can cooperate between various energy reasonable, implement different forms, different grade energy cascade utilization, in order to obtain the best effect of comprehensive utilization of energy of the system.
冷热电三联产系统是由一种一次能源连续产生两种以上的二次能源的系统,燃气燃烧把化学能转化为热能,高品位的热能用来发电(燃料电池冷热电三联产系统直接把天然气的化学能转化为电能),低品位的热能用于供热或者为吸收式、吸附式制冷系统提供驱动热源,从而实现对燃气化学能的多级多次利用。
Cold hot electricity cogeneration system is composed of a primary energy continuously produce two or more of the two energy system, fuel gas combustion to convert chemical energy into heat energy, high grade heat energy used to power generation, fuel cell cold hot electricity cogeneration systems directly convert the chemical energy of gas for electricity), low grade heat energy used for heating or for absorption and adsorption refrigeration system driving heat source, so as to realize multi-stage repeatedly used for gas chemical energy.
根据采用的原动机不同,冷热电联产系统分为两类:
Depending on the prime mover, cold hot electricity co-generation system is divided into two categories:
1)以燃气机为原动机的系统
1) gas machine as the prime mover system
燃气机与柴油机类似,同属内燃机,为往复运动机械,再将往复运动转变为回转运动, 驱动发电机组。发电效率为(20~35)%,热电综合利用效率为80%。排热回收形态主要为(400~600)℃的排气与(85~90)℃的热水,可用于采暖、供热水与制冷。发电量规模一般为(15~1000)kW的中小型容量,日本已有容量(15~300)kW机组型的产品[1]。
Gas machine similar to diesel, belong to the internal combustion engine, for reciprocation machinery, then reciprocating motion into rotary motion, drive the generator. Power generation efficiency is (20 ~ 35) %, comprehensive utilization of thermoelectric efficiency of 80%. Main exhaust heat recovery form for exhaust (400 ~ 600 ℃) and (85 ~ 90 ℃ of hot water, can be used for water heating, heating and refrigeration. Output size is commonly (15 ~ 1000 kW) of small and medium capacity, Japan's existing capacity type (15 ~ 300 kW units products [1].
2)以燃气轮机为原动机的系统
2) gas turbine as the prime mover system
可直接传递回转能带动发电机组,发电效率为(20~40)%,热电综合利用效率为80%.不用冷却水,排热回收形态主要是排气,排气温度(400~550)℃,排气经废热锅炉产生蒸汽或热水,用于采暖、供热水与制冷,也可将排气直接用于吸收式制冷机组制冷。发电规模为(1000~3000)kW的大型容量。但随着微型燃气轮机的发展,小容量的发电机组得到发展。日本已生产以城市煤气为能源的微气体发电机组,最小容量为290kW[1]。
Can directly turn to drive the generator set, power efficiency (20 ~ 40) %, comprehensive utilization of thermoelectric efficiency was 80%. No cooling water, mainly is the exhaust heat recovery form, exhaust temperature (400 ~ 550 ℃), exhaust gas after waste heat boiler to produce steam or hot water, and used for heating water, heating and refrigeration, and exhaust can be directly used for absorption refrigeration refrigeration unit. For wind farm scale, large capacity (1000 ~ 3000 kW). But with the development of the miniature gas turbine, small capacity of the generating set was developed. Japan has been in the production of city gas as the energy micro gas generating set, the minimum capacity of 290 kw [1].
2.4 天然气除湿空调系统
2.4 gas desiccant air conditioning system
普通的空调器的除湿功能只有在被冷却的房间温度低于露点时,才具有一定的除湿能力,但也是有限的,其调节能力较差,因此需要专门具有除湿功能的空调系统[2]。目前,以天然气作为驱动能源的除湿空调系统主要有如下两种形式:
Ordinary dehumidification function of air conditioner only when in the cooling room temperature below the dew point, only has a certain dehumidification capacity, but it is also limited, its adjustment ability is poorer, so need special dehumidification function of air conditioning system [2]. At present, the main energy with natural gas as a driving desiccant air conditioning system has the following two forms:
1)除湿蒸发冷却系统
1) the desiccant evaporation cooling system
该系统采用溶液作为除湿剂,在除湿器中对新风进行除湿,吸收水分成为稀溶液,必须在再生器中被再生热源加热,除去水分提高浓度才能恢复其除湿功效。以太阳能、余热或其它低温热源会有很多不方便之处,影响其推广使用,而使用天然气加热是一个比较理想的办法,可以说天然气除湿蒸发冷却系统是新型的节电、节能、经济的空调技术,其理论COP值可以达到1左右。
Solution as liquid desiccant, this system is used for air dehumidification in the dehumidifier, absorb water dilute solution, must be renewable heat source heating in the regenerator, remove moisture increase the effectiveness of concentration to restore its moisture. To solar energy, waste heat or other low-temperature heat source, there will be many not convenient place, affect their use, and use natural gas heating is an ideal way to say that gas desiccant evaporative cooling system is a new type of energy-saving air conditioning technology, energy saving, economy, its theoretical COP value can reach 1 or so.
2)燃气用于转轮再生的干燥空调方式
2) fuel gas used in the wheel regenerative dryer air conditioning mode
在空调机组中加入转轮除湿机,室外新风先进入转轮除湿机进行除湿处理,除湿后的干空气再进入空调机进行空调处理,然后进入空调室完成制冷、采暖过程。转轮除湿机由吸湿转轮、传动机构、外壳、风机及再生用加热器等组成。用来吸收室外新风中水分的吸湿剂一般为硅胶或分子筛。当吸湿剂达到含湿量的极限时会失去吸湿能力,为重复使用需进行再生处理。再生处理是用(180~240)℃的热空气加热吸湿剂,使其所含水份蒸发。而热空气就是通过在再生加热器中利用天然气燃烧后的排热与空气进行热交换获得的。这种干燥空调方式的优点有:充分利用天然气燃烧后的排热,起到节能的作用;对空气分别进行湿度和温度的处理,能承担较大的冷负荷和湿负荷,且避免了为满足湿度要求制冷机在低蒸发温度下运转, 效率降低的弊端,有较好的经济性。
Add wheel dehumidifier in air conditioning units, fresh air into the first wheel dehumidifier dehumidification processing, after the desiccant dry air to enter air conditioning air conditioning, and then enter the air conditioning room to complete refrigeration, heating process. Wheel dehumidifier by hygroscopic wheel, transmission mechanism, shell, fan and regeneration with heater, etc. Used to absorb the moisture from the outdoor air for silica gel or molecular sieve moisture absorption agent. When hygroscopic agent when they reached the limit of the moisture content loss of moisture absorption ability, regeneration for reuse to processing. Regeneration treatment is used (180 ~ 240 ℃ hot air heating hygroscopic agent, so that the water evaporation. And the hot air is through the use of natural gas combustion in regenerative heater heat removal and air after heat exchange. This way of dry air has the advantages of: make full use of natural gas after combustion heat removal, have the effect of energy saving; Handling of air humidity and temperature respectively, can bear larger cooling load and moisture load, and avoid to meet the requirements of humidity machine running under low evaporation temperature, low efficiency, has better economy.
3.燃气空调的经济性和其带来的社会效益
3. The economy of gas-fired air conditioning and its social benefits
许多学者和国内的一些企业针对以天然气作为驱动能源的空调器的经济性作了相关研究,一致认为燃气空调器比电空调器更具竞争力。文献[3] 的研究表明,目前国内天然气价格与等热值的电力价格之比为约为3.8∶1,吸收式燃气空调器供热费用低于电空调,以天然气为燃料的吸收式燃气空调器的制冷循环与电空调器相比很有竞争力。文献[4]表明吸收式燃气空调不仅具有用电少、环境污染轻等优点,而且其建设投资和运行费用(未包括折旧费和人工费等)均低于常规集中空调。文献[5]的研究显示,从一次能源的角度看,燃气空调的一次能耗不低于电力空调方案,且节能性较好。文献[6]认为在目前的能源价格等条件下,天然气热泵的年单位面积总成本低于电动冷热水机组、燃气锅炉和冷水机组。文献[7]的研究表明,如果燃气空调采用楼宇冷热电联产技术,可大幅度提高能源利用率,其能源综合利用率可达到80%~90%,与大型热电联产比较,楼宇冷热电联产可以减少输配电系统和供热管网的投资,无论从减少投资成本和减轻污染来讲都是十分有利的。
Many scholars and some domestic companies for as driver energy efficiency of air conditioner using natural gas as the related research, agreed that the gas air conditioner air conditioner more competitive than electricity. Literature [3] the study showed that the current domestic natural gas prices and calorific value of the ratio of the price of electricity, such as to about 3.8:1, absorption gas air conditioner heating costs less than electricity air conditioning, gas air conditioner using natural gas as fuel of absorption refrigeration cycle compared with the electric air conditioner is very competitive. Literature [4] indicate that absorption of gas air-conditioning not only has the advantages of less electricity and light pollution of the environment, and its construction investment and operation cost (not including depreciation cost and artificial cost, etc.) are lower than conventional central air conditioning. [5], according to research from an energy perspective, gas air conditioning energy consumption of a not under power air conditioning scheme, and good energy-saving sex. Literature [6] think under the condition of the current energy price, annual total cost per unit area is lower than the electric gas heat pump hot and cold water unit and gas boiler and chiller. Literature [7] research shows that if gas air conditioning USES the building cold hot electricity co-generation technology, can greatly improve energy efficiency, its energy integrated utilization rate can reach 80% ~ 90%, compared with large cogeneration, building heating and electricity co-generation power transmission and distribution system and the heating pipe network investment can be reduced, no matter from reduce investment costs and reduce pollution is very favorable.
此外,目前我国各种能源的价格并不十分合理,尤其是天然气的价格,与国际惯例并不一致。在北京,1m3天然气1.6元多,相当于4kWh电的费用,在国外1m3气大约相当于2kWh多电的费用,因为1m3天然气可以发3kWh电[8]。随着我国能源结构的调整及经济的发展,我国各种能源的价格将趋于合理化,城市天然气的价格相对于电价将会有所降低,这将使得燃气空调的运行费用将会进一步下降。还有一点就是针对我国夏季是用电高峰、用气低谷,冬季为用电低谷、用气高峰的能源消费现状,已有部分地区实行了峰谷电价,可以预见今后在全国主要城市必然要推行峰谷电价,而随着天然气的广泛使用,也必将会实行峰谷气价,而燃气空调的使用时间正赶上峰值电价和谷值气价,必将大大节省运行费用。以目前日本燃气空调用户来说,由于国家实行了峰值电价和谷值气价,鼓励夏季更多地使用天然气,其运行费用就比电力空调低一倍以上[9]。
In addition, the price of all kinds of energy in China is not very reasonable, especially the price of natural gas, are not consistent with international practice. In Beijing, more than 1 m3 natural gas to 1.6 yuan, equivalent to 4 KWH electricity costs, abroad more than 1 m3 gas equivalent to about 2 KWH electricity costs, because 1 m3 natural gas can send 3 KWH electricity [8]. With China's energy structure adjustment and economic development, all kinds of energy price in China will tend to rationalize, city natural gas prices relative to the price will be reduced, this will make the operating cost of gas air conditioning will decrease further. There is summer is a peak in China, gas breakdown, winter for electricity trough, the gas peak energy consumption present situation, the parts have been implemented peak valley electricity, can foresee the future in the major cities in China is bound to promote peak valley price, but with the wide use of natural gas, will also implement the peak valley price gas, and gas air conditioning use time is to catch up with peak electricity price and value, will certainly greatly saves the operation cost. At the current gas air conditioning users in Japan, because the state practices the system of electricity and the peak value gas price, encourage more use of natural gas in summer, the operating cost is lower than the electric air conditioning a times above [9].
另外,发展燃气空调还能为国家带来很大的社会效益,提高天然气管网的利用率,降低相对维护成本。目前的天然气输送管网的利用率很低。以陕北到北京的天然气输送管道为例,由于季节供气不平衡,管线供气能力有30个亿,实际用气只有10多个亿,管网利用率只有30%左右,冬夏差非常大,冬季高峰的平均用气量是夏季最低月份的平均用气量的5倍[2],季节不平衡非常严重,最直接的后果是经济成本加大。虽然建设地下储气库可以解决用气不平衡问题,但成本依旧很高。因此,发展燃气空调,提高管网利用率的同时也降低季节用气的不平衡性,有“一举两得”的功效。
In addition, the development of gas-fired air conditioning still can bring great social benefits for the country, improve the utilization rate of natural gas pipeline network and reduce the maintenance costs relatively. The gas pipe network utilization is very low. In northern shaanxi to Beijing natural gas pipeline as an example, due to seasonal supply imbalance, pipeline gas supply capacity is $30, actual gas only more than 10 billions, network utilization rate is only 30%, winter and summer difference is very big, the winter peak in summer minimum average is the average gas gas five times [2], seasonal imbalance is very serious, the most direct consequence is more economic cost. Although the construction of underground gas storage can solve the problem of unbalanced gas, but the cost is still high. Therefore, development of gas air-conditioning, improve the utilization ratio of network also reduce seasonal imbalance of gas at the same time, have the effect of "kill two birds with one stone".
目前,西部大开发是我国的一项重大经济发展政策,西气东输又是西部大开发的一个重要组成部分,也是我国的一项重要能源调整政策。合理利用天然气,关系到西气东输政策的成败,而燃气空调则是天然气资源的一种较好的利用方式。从美国加州2001年夏季、2002年夏季发生了几次电力危机和今夏我国众多省份拉闸限电来看,连日高温导致发电厂超负荷运行,其中大量使用电空调器是导致电力危机的一个重要原因[2],这也说明发展燃气空调,使之与电空调器构成合适的使用比例,从而减少电空调器在夏季对电网的冲击,可以避免类似的能源危机在我国发生。
At present, the development of the western region is a major economic development policy in China, the west to east gas pipeline is an important part of the western development, is also an important energy adjustment policies of our country. Rational utilization of natural gas, and relates to the success or failure of the policy of west-east gas, and gas air conditioning is a way of better use of natural gas resources. California in the summer of 2001, in the summer of 2002 from the United States happened a few times electric power crisis and electricity in many provinces this summer, days of high temperature in power plants run overload, the extensive use of electric air conditioner is an important cause of the electricity crisis [2], it also suggests that development of gas air-conditioning, electric air conditioner with constitute the use of appropriate proportion, thus reducing the electric air conditioner impact to power grid in the summer, can avoid a similar energy crisis in our country.