Biological matter pyrolysis gasifying detarring catalyst and preparing method
A, technical field: The invention relates to a catalyst and method for preparing the same, in particular to a biomass pyrolysis gasification detarring catalyst and method for preparing the same. B, technical background China's annual production of various straw about 10 million tons, and in agriculture and forestry products of the industrial enterprise biomass as raw material also generate several hundred million tons of processing residues. Biomass resources are a renewable clean energy, can realize CO2 zero discharge, thereby greatly reducing the greenhouse effect and environmental pollution. In order to high-tech development and utilization of biomass energy, replacing petroleum, coal and other mineral energy, is to solve the problems of energy and environmental issues one of the important ways. From the current view of the progress of the study on, biomass pyrolysis gasification technology has the advantages of high efficiency, the adaptability of the raw material is strong, the apparatus is simple, the advantages of low investment, at this stage in the rural areas of our country is good for a certain period of time in the future and the technical, economic level, and not subject to geographical, climatic constraints. In many biomass utilization technique, biomass pyrolysis gasification the most promising, through this kind of process, can produce valuable gas for domestic and industrial use. In biomass pyrolysis gasification process will inevitably contain a certain amount of tar. When the in order to produce the primary purpose of the fuel gas, tar and gas not only lead to the presence of reduced thermal efficiency, at low temperature also will condense to liquid, and thereby water and dust clogging and corrosion equipment, serious at the time when the normal operation of the equipment. Commonly used water elution tar technical need to consume valuable water resources and can easily cause serious secondary pollution, it is difficult to clean tar in the flue gas. Biomass gasification gas in the tar to block the the problem is serious, the straw gasification in rural areas has been completed on the majority of the gas cannot operate normally, existing small domestic biomass gasification furnace is also widespread blockage problem of tar, and constitute a potential safety hazard. In response to the problems caused by biomass gasification of tar, tar at home and abroad by academics resolved catalytic cracking process. Catalytic cracking catalyst method is through the tar cracking under the high temperature H2, CH4, at the same time reduce CO2 content, the proportion of combustible components in the gas. Ni-Al2 O3, the tar cracking load nanometer MgO with glomeromycota catalytic role and better effect, and catalytic cracking temperature is greatly reduced (in the 350-500 [...]), but the high cost of the catalyst. Ordinary dolomite as the catalyst, the catalytic activity is low, catalytic decoking oil efficiency is low. Chinese Patent public number CN1686606A, name is a biomass gasification catalyst and its production method. Discloses "a biomass gasification catalyst and production method thereof". The catalyst is made up of "attapulgite clay, bauxite, iron oxide, a magnesium oxide calcium oxide and anthracite coal". The above-mentioned catalyst in the tar current 75% or more, the gasification rate of 15%, the fuel gas heat value of 20%. The junction in jingsu and Anhui regions are rich attapulgite clay resources. Attapulgite clay ore-type is divided into four: attapulgite clay (attapulgite content of greater than 70%), ascanite attapulgite clay (attapulgite content 20-50%, ascanite content is greater than 50%), opal attapulgite clay (comprising a plurality of opal), dolomite attapulgite clay (dolomite content is greater than 20%). The attapulgite clay ore the CPC have a large number of dolomite attapulgite clay, and with other types of attapulgite clay interbed outputs. When the exploitation of attapulgite clay, dolomite attapulgite clay is piled up for a long time as the proposed. The dolomite attapulgite clay has not been very good use, not only increases the attapulgite clay mining cost, and because a large number of stacking cause a serious ecological damage to the environment. Typical dolomite attapulgite clay ore chemical ingredient is: SiO2, 33.14% ; CaO, 15.9% ; MgO, 15.7% ; Fe2 O3, 2.48% ; Al2 O3, 3.69% ; TiO2, 0.39% ; overproof, 28.14% For the applicant and high-resolution transmission electron microscope, scanning electron microscope to dolomite attapulgite clay study found, dolomite attapulgite clay in the grain size of dolomite 200 nm left and right, surface a few nanometers of growth or corrosion step, internal has rich nano-corrosion hole. This is the first time that the applicant is very rare nature of the nano-structure is characterized in (Figure 1, 2). Wherein the attapulgite diameter 40 nm, length 300-800 nanometer. Dolomite attapulgite clay mineral which has a unique, the performance of the micro-structure and unique natural nanometer material. Three, the content of the invention The invention aims to remove the biomass pyrolysis gasification of tar, the technical problem to be solved is tar cracking catalyst used. The said DeTar catalyst is dolomite content is 20-70%, attapulgite content is 20-80% of dolomite attapulgite clay through grinding, forming and for 500-900 the condtions [...] 2-4 hours of activation is columnar or ring-shaped or granular catalyst, specific surface area is 25-125m2/g, pore volume of 0.3-0.4 ml/g. The preparation method of the catalyst, using dolomite attapulgite clay as raw materials, the dolomite content is 20-70%, attapulgite content is 20-80%, including crushing, shaping and activation, is characterized in that the activation that is, forming after the 500-900 [...] condtions 2-4 hours, preferably 600-750 the condtions [...] 2-3 hours. Dolomite attapulgite clay after high temperature calcination, attapulgite nano crystal morphology and adsorption activity keeps unchanged, dolomite decomposition produces a nano-MgO particles about 20 nanometer, in ceramic dielectic and load surface, to constitute the nano lhc (see Figure 4). This complex has very high specific surface area and of the tar adsorption and catalytic cracking activity. Dolomite attapulgite clay in the dolomite thermal activation of an MgO particles of calcined dolomite than MgO particle is small, and the artificial synthetic specialized load of similar particle size of MgO, has very high and the adsorption capacity of the catalytic activity. Straw gasification furnace through the test indicates that the catalytic cracking of tar, tar removal rate reaches 90% or more. The catalyst raw material is cheap, easy to obtain, simple preparation process, tar removal rate is high, is easy to be popularized. Four, Figure description Figure 1 the raw material of catalyst is dolomite attapulgite sticks the depot emission scanning electron microscope Image. Display attapulgite (fibrous crystal) and dolomite (granular particles) interactive inlays lives , development gap, display relatively high voidage, dolomite crystal grain diameter approximately 200-300nm, it is found that the nature of the small maximum grain size of the dolomite, has higher activated. Figure 2 the catalyst raw materials dolomite attapulgite sticks the depot emission scanning electron microscope Image. Display dolomite attapulgite clay in the hollow of the dolomite crystal contains abundant, corrosion such as steps in the micro-structure of nanometer size. Figure 3 the catalyst raw materials dolomite attapulgite clay high-resolution transmission electron microscope Image, display clay in the dolomite topography, display with nano-particle size and mineral is of nanometer such as nano-empty. Figure 4 is high-resolution transmission electron microscope picture of the invention preparing catalyst like, display catalyst activating generating in the dolomite-crystal MgO (20 nano granular particles) loaded on the surface of ceramic dielectic, to constitute the nano composite, the complex has very high specific surface area and of the tar adsorption and catalytic cracking activity. Five, specific embodiment (A) preparation of catalyst In the areas of junction Jiangsu dolomite attapulgite clay ore as raw materials for preparing a catalyst for example, wherein the dolomite content is 60%, attapulgite is in a content of 35%, mineral silica and feldspar impurity content of from about 5%, non-limiting embodiments are described below: 1. The dolomite attapulgite clay crushing, sieving to obtain 0.5-6 mm of the granular material, the 700 the calcining [...] 2 hours, to obtain granular detarring catalyst. 2. The dolomite attapulgite clay crushed to particle size ≤ 0.1 mm powder. In the powder is added into the shucker, spray by adding a proper amount of water, dolomite attapulgite clay rolling spherulization, got particle size 1-6mm particle, then in an oven the 105 [...] drying. The prepared granule 650 the calcining [...] 3 hours, to obtain granular detarring catalyst. 3. The dolomite attapulgite clay crushed to particle size ≤ 0.1 mm powder. The powder and binder the CMC and water after mixing is diameter 1-6mm, long 8-10mm of the cylindrical or annular, first placed in an oven to dehydrating and drying, then the 750 when [...] calcined 2 hours, to obtain the columnar or ring detarring catalyst. (B) removing tar test Preparation of the catalyst filling the catalytic reactor DeTar, coagulation of the gasification furnace with the straw to the object to be catalytic experiment catalytic cracking, catalytic reaction temperature of the 600 when [...] , tar removal rate reaches 90% or more. The invention relates to a catalyst of taking off biomass Thermal Gasification tar,Dolomite concavo convex stone clay get the granular or columnar or ring catalyst through crushing,molding and activating, the special surface is 25-1252/g, pore volume is 0.3-0.4ml/g. the described activation after molding calcine 2 to 4 hours under 500-900deg.C. The catalyst tar removal rate reaches more than 90%. 1, a biomass pyrolysis gasifying detarring catalyst, characterized in that the catalyst is dolomite content is 20-70%, attapulgite content is 20-80% self-marble attapulgite clay through grinding, forming and for 500-900 the condtions [...] 2-4 hours activation get the granular or columnar or ring-shaped catalyst, specific surface area is 25-125m2/g, pore volume of 0.3-0.4 ml/g. 2, the catalyst preparation method according to Claim 1, the method using dolomite attapulgite clay as raw materials, the dolomite content is 20-70%, attapulgite content is 20-80%, the method comprises grinding, forming and activation, characterized in that the activation is formed after the 500-900 [...] condtions 2-4 hours. 3, preparation method according to Claim 2, characterized in that the activation is formed after the 600-750 [...] condtions 2-3 hours.